Kansas Geological Survey, Technical Series 23, originally published in 2011
An Acrobat PDF file containing the complete report is available (3.4 MB).
The major and trace element content of 123 lamproites and associated sedimentary rock samples from six cores of the Silver City Dome and two cores from the Rose Dome in southeastern Kansas were analyzed. The lamproites are ultrapotassic (weight percent K2O/Na2O = 2.0 to 22.1), alkalic (molecular [K2O + Na2O]/Al2O3 = 1.01 to 3.04), and are enriched in mantle-incompatible elements (e.g., light REE, Ta, Hf, Ba, Rb, Sr, Th). The low Al2O3 content of these samples is consistent with lamproites formed in stable continental settings such as those from West Kimberley, Australia, and Smoky Butte, Montana. Also the lack of a significant negative Ta and Nb anomaly in mantle-normalized plots precludes the source rocks having been involved in subduction.
The samples from the Silver City cores are composed of mostly serpentinized olivine and mica with lesser amounts of K-richterite, diopside, rutile, apatite, perovskite, and spinel in a serpentinized groundmass. The Rose Dome cores contain mostly serpentinized olivine and mica with minor diopside, spinel, perovskite (more abundant than at Rose Dome), xenotime, and feldspar. Most mica compositions follow the trend of decreasing FeO and Al2O3 similar to trends of the Guess Core and the Wolgidite trend at West Kimberly. Micas enriched in Ba and Ti (BaO = 16.6-19.3 weight percent; TiO2 = 26.0- 27.8 weight percent) rim some micas of more normal composition. These very high Ba and Ti-rich micas have not been found in other lamproites or other types of alkalic rocks.
The average composition of the shallow cores at the Silver City Dome are similar to one another (except for Na2O, Li, and Cs), although the average composition of the shallow cores are different than the previously studied deeper Guess and Ecco Ranch cores in this area. The average composition of the two Eagle cores at Rose Dome are similar to one another, but they are higher in Fe2O3 (total), MgO, CaO, P2O5, Th, Co, Ni, Cr, U, Y, REE, Cu, and Cs concentrations than the shallow cores from the Silver City Dome.
Metasomatized mantle (lherzolite-harzburgite) containing varied amounts of veins containing clinopyroxene, K-Ti amphibole, phlogopite, apatite, and K-Ba-Zr-Nb titanates could have melted in varied amounts to form the lamproites. The lower SiO2 and Al2O3 and higher MgO lamproites at Rose Dome likely result from melting at a higher temperature of more lherzolite-harzburgite and less vein material than the more SiO2-rich and MgO-poor lamproites at Silver City.
Also the concentration of most elements varies vertically in the cores, and the variation in the elemental concentration can be related to mineral gravity settling, flow differentiation, or volatile transport processes within the sills. For example, at the Silver City Dome, concentrations of olivine and phlogopite can be related to the samples with the lowest SiO2 and highest MgO, Mg#, Ni, and Co content. The portions of the cores with the highest concentrations of K2O, Al2O3, and Sc may be correlated to samples with the highest phlogopite. Also Ba often decreases in amount upward in many cores at the Silver City Dome and is enriched in overlying hornfels compared to the unaltered overlying shale. Ba movement in H2O-rich fluids into the overlying hornfels can explain this observation. Curiously, overlying limestones are not enriched in Ba, so at least locally the limestones may be impervious to the fluids.
The major elements and trace elements were analyzed by X-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry (ICP-MS) at the SRS Company in Toronto, Canada. One to 15 grams of each sample (pre-dried at 105°C for about 8 hours) were dissolved in aqua regia in a 80°C-90°C water bath and were diluted as needed for ICP-MS analyses. The diluted samples were analyzed on either an Elan 6100 or PQ3 mass spectrometer. An in-house reference standard was analyzed every 48th sample, and duplicates were analyzed every 12th sample. Results of the U.S. Geological Survey standard basalt, BIR-1, are given in table 1 along with average values from other sources (Govindaraju, 1994).
Table 1--A comparison of X-ray fluorescence values and ICP-MS values of BIR-1 with one another and with those of others.
X-ray Fluorescence |
ICP-MS | USGS Certified Values1 Mean (St. Dev.) |
Geostandards Newsletter2 |
ICP-MS3 | |
---|---|---|---|---|---|
SiO2 | 47.7 | 47.96 (0.19) | 47.77 | ||
TiO2 | 0.99 | 0.96 | 0.96 (0.01) | 0.96 | |
Al2O3 | 15.3 | 15.5 | 15.5 (0.15) | 15.35 | |
Fe2O3(total) | 11.5 | 11.0 | 11.3 (0.12) | 11.26 | |
MnO | 0.17 | 0.17 | 0.175 (.003) | 0.17 | |
MgO | 9.81 | 9.41 | 9.70 (0.079) | 9.68 | |
CaO | 12.9 | 12.9 | 13.3 (0.12) | 13.2 | |
Na2O | 1.77 | 1.82 (0.05) | 1.74 | ||
K2O | 0.024 | 0.030 (0.003) | 0.027 | ||
P2O5 | 0.02 | 0.01 | 0.021 (0.001) | ||
LOI | 0.01 | ||||
Rb | 0.3 | 0.25 | 0.32 | ||
Ba | 12 | 7 | 7 | 9.7 | |
Sr | 136 | 105 | 110 (2) | 108 | 94.2 |
Th | 0.05 | 0.03 | 0.04 | ||
Hf | <1 | 0.6 (0.08) | 0.6 | 0.61 | |
Zr | 20 | 15 | 18 (1) | 15.5 | 13.8 |
Ta | <0.5 | 0.04 | |||
Co | 55.9 | 52 (2) | 51.4 | 54.2 | |
Sc | 39 | 44 (1) | 44 | 41 | |
Ni | 168 | 170 (6) | 166 | 174 | |
Cr | 374 | 370 (8) | 382 | 399 | |
U | <0.05 | 0.01 | <0.03 | ||
Y | 13 | 16.1 | 16 (1) | 16 | 14.4 |
Nb | <2 | 3 | 0.6 | 2.11 | |
La | 0.66 | 0.63 (0.07) | 0.62 | 0.61 | |
Ce | 2.0 | 1.9 (0.4) | 1.95 | 1.85 | |
Pr | 0.41 | 0.37 | 0.36 | ||
Nd | 2.6 | 2.5 (0.7) | 2.5 | 2.21 | |
Sm | 1.1 | 1.1 | 1.1 | 1.06 | |
Eu | 0.54 | 0.55 (0.05) | 0.54 | 0.49 | |
Gd | 1.9 | 1.8 (0.4) | 1.85 | 1.63 | |
Tb | 0.36 | 0.36 | 0.33 | ||
Dy | 2.6 | 4 (1) | 2.5 | 2.33 | |
Ho | 0.6 | 0.57 | 0.52 | ||
Er | 1.79 | 1.7 | 1.54 | ||
Tm | 0.26 | 0.26 | 0.22 | ||
Yb | 1.7 | 1.7 (0.1) | 1.65 | 1.52 | |
Lu | 0.25 | 0.26 | 0.26 | 0.23 | |
Cu | 126 | 125 (4) | 126 | 126 | |
Li | <10 | 3.6 (0.2) | 3.4 | 3.3 | |
Zn | 65 | 70 (9) | 71 | 80.6 | |
Cs | <.1 | 0.005 | 0.04 | ||
Ga | 14 | 16 | 16 | 15.2 | |
Ge | 2 | 1.5 | |||
Pb | <5 | 3 | 3 | 3.08 | |
V | 294 | 310 (11) | 313 | ||
1--USGS certified values are the March 1998 values by David B. Smith, USGS website--http://minerals.cr.usgs.gov/geo_chem_stand/icelandic.html. Numbers without a standard deviation are information values. 2--Govindaraju, K., 1994 3--Garbe-Schonberg, 1994 |
The pre-dried samples were also analyzed using XRF. Two grams of each sample were heated in an oxygen-purged furnace at 950°C for 1 hour. The samples were mixed with 7.7 grams of a 50/50 mix of lithium tetraborate and lithium metaborate and fused in an automatic fluxer. The melt was poured into a platinum mold to form a 40-mm glass disk. Loss on ignition (LOI) was obtained from the weight loss on heating at 950°C as described above. The glass disks were analyzed on an automated Siemens SRS-3000 X-ray fluorescence spectrometer that was calibrated using 41 different rocks. Duplicates of samples were analyzed every 20th sample, and a house control sample was analyzed every 55th sample. Results of the BIR-1 using XRF are also given in table 1. Results of the SRS analyses on BIR-1 generally agreed with the averages of other analysts.
Also a number of samples were rechecked using ICP-MS at the University of Kansas using similar techniques as those of the SRS. Most results agreed well between labs and by different techniques, so the results on the same sample were averaged.
The geology of the lamproites and associated sedimentary rocks is described in Berendsen (2011). The location of the cores used in this study are shown in fig. 1 and also given in Berendsen (2011).
The mineralogy of the lamproites at the surface at the Silver City Dome are porphyritic with megacrysts of mostly serpentinized olivine and mica with lesser diopside, chrome spinel, and richterite (Franks et al., 1971; Cullers et al., 1985; Coopersmith and Mitchell 1989). The groundmass is mostly serpentine.
Figure 1--Location study area and of cores used in this study (Silver City dome to right and Rose dome to lower left).
The deeper Guess Core (305-312 m [1,000-1,023 ft] depth) and Ecco Ranch Core (237.5-247.5 m [779-812 ft] depth) at Silver City Dome are fine to coarse grained with usually little groundmass (Cullers et al., 1996). The main minerals in the Guess Core are mica and sanidine with lesser richterite, diopside, Ca-Si zeolite, apatite, shcherbakovite, wadeite, and perovskite. The main minerals in the Ecco Ranch Core are mica, sanidine, and richterite with lesser diopside, Ca-Si zeolite, and sphene. This sill is enriched in sanidine and depleted in mica and richterite in the mid to lower portions of the sill relative to the upper portion of the sill.
The mineralogy of the shallow cores (92, 97, and 98 series) at the Silver City Dome is similar to that of the previously studied surface samples. Thus, the cores are composed of mostly serpentinized olivine and mica with lesser amounts of K-richterite, diopside, rutile, apatite, perovskite, and spinel in a serpentinized groundmass. Coarser crystals of especially serpentinized olivine, and to a lesser extent, mica, richterite, and diopside, are concentrated toward the center to lower center portions of the cores.
In contrast, cores at the Rose Dome contain somewhat different mineralogy compared to those at the Silver City Dome. For example, Eagle 4, like the shallow Silver City Dome cores, contains mostly serpentinized olivine and mica with minor diopside, spinel, and perovskite. The amount of perovskite, however, is often much more abundant in the Rose Dome cores (up to 5%) than the Silver City Dome cores (less than 1%). In addition, the Silver City Dome cores also may contain minor xenotime and feldspar.
A few of the mineral compositions of representative samples of the lamproites also have been analyzed. The clinopyroxenes from the shallow Silver City cores are diopside with fairly low concentrations of Al2O3, FeO, Na2O, and TiO2 (table 2). The clinopyroxene compositions are similar to those of the deeper cores at the Silver City Dome and to those of West Kimberly (fig. 2).
Table 2--Mineral compositions of the lamproites.
Mica | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
92-11 89'2" |
|
SiO2 | 41.457 | 40.737 | 41.242 | 28.381 | 29.151 | 29.796 | 30.14 | 29.638 | 40.894 | 40.64 |
TiO2 | 4.994 | 4.98 | 5.051 | 25.97 | 27.846 | 27.214 | 27.7 | 27.728 | 5.494 | 5.14 |
Al2O3 | 2.946 | 4.933 | 1.559 | 0.047 | 0.184 | 0.049 | 0.112 | 0.049 | 7.786 | 8.203 |
FeO | 11.996 | 10.274 | 13.308 | 2.558 | 3.078 | 2.954 | 2.853 | 2.198 | 7.543 | 7.246 |
MgO | 22.157 | 22.142 | 22.126 | 3.916 | 2.62 | 2.382 | 2.333 | 3.243 | 22.299 | 22.548 |
CaO | 0 | 0.015 | 0.023 | 1.878 | 2.055 | 2.011 | 1.754 | 1.885 | 0 | 0.001 |
K2O | 9.877 | 10.225 | 9.712 | 5.542 | 5.725 | 5.559 | 5.648 | 5.916 | 10.534 | 10.585 |
BaO | 0.656 | 0.695 | 0.269 | 19.316 | 16.569 | 17.202 | 17.367 | 17.583 | 0.115 | 0.616 |
Na2O | 0.073 | 0.056 | 0.297 | 6.311 | 6.169 | 7.054 | 6.974 | 6.888 | 0.051 | 0.068 |
Cr2O3 | 0.079 | 0.106 | 0.023 | 0 | 0.168 | 0.25 | ||||
MnO | 0 | 0.05 | 0.074 | 0.343 | 0.8665 | 0.715 | 0.0781 | 0.517 | 0.005 | 0.033 |
H2O | 3.964 | 3.988 | 3.916 | 3.364 | 3.436 | 3.449 | 3.481 | 3.477 | 4.159 | 4.162 |
Total | 98.199 | 98.201 | 97.599 | 97.625 | 97.698 | 98.384 | 99.142 | 99.123 | 99.047 | 99.491 |
Mica, continued | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 413'4" |
Eagle 4 413'4" |
Eagle 4 413'4" |
Eagle 4 413'4" |
||
SiO2 | 40.86 | 40.12 | 44.37 | 41.22 | 40.41 | 40.597 | 41.81 | 40.32 | 37.9 | |
TiO2 | 1.7 | 2.03 | 0.93 | 1.47 | 1.73 | 0.364 | 0.06 | 2.97 | 2.05 | |
Al2O3 | 5.5 | 5.77 | 7.22 | 5.05 | 5.78 | 5.38 | 3.006 | 1.71 | 0.6 | |
FeO | 10.93 | 11.24 | 8.9 | 12.49(Fe2O3) | 12.68(Fe2O3) | 16.99 | 21.4 | 14.05 | 24.12 | |
MgO | 24.61 | 23.84 | 22.07 | 24.81 | 24.33 | 21.11 | 18.69 | 23.39 | 16.72 | |
CaO | 0.06 | 0.03 | 0.45 | 0.01 | 0 | 0.054 | 0.12 | 0 | 0.02 | |
K2O | 10.65 | 10.47 | 7.74 | 10.68 | 10.47 | 10.01 | 9.94 | 9.93 | 9.42 | |
BaO | 0.02 | 0.06 | 0.63 | 0.32 | 0.36 | 0.006 | 0.01 | 0.56 | 0.07 | |
Na2O | 0.02 | 0.05 | 0.1 | 0.04 | 0.02 | 0.24 | 0.71 | 0.1 | 0.2 | |
Cr2O3 | 0.13 | 0.17 | 0 | 0.1 | 0.15 | 0.1 | 0 | 0.02 | 0.07 | |
MnO | 0.07 | 0.04 | 0.16 | 0.07 | 0.03 | 0.34 | 0.31 | 0.1 | 0.54 | |
H2O | 4 | 3.96 | 4.07 | 4.14 | 4.12 | 3.93 | 3.88 | 3.86 | 3.59 | |
Total | 98.52 | 97.79 | 96.64 | 100.4 | 100.07 | 99.13 | 99.95 | 97 | 95.32 |
Serpentine | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
|
SiO2 | 47.224 | 40.915 | 43.044 | 38.249 | 48.668 | 46.712 | 49.845 | 39.597 | 42.087 | 44.92 |
TiO2 | 0.249 | 0.084 | 0.049 | 0.025 | 0.012 | 0.196 | 0 | 0 | 0.01 | 0.29 |
Al2O3 | 2.06 | 0.196 | 1.058 | 0.001 | 2.004 | 1.997 | 0.437 | 0.002 | 0 | 3.77 |
FeO | 8.689 | 6.062 | 5.042 | 6.942 | 9.01 | 7.511 | 11.11 | 5.906 | 2.36 | 5.44 |
MgO | 29.549 | 38.118 | 37.3 | 38.961 | 27.793 | 30.819 | 26.935 | 39.73 | 41.787 | 31.37 |
CaO | 0.288 | 0.179 | 0.115 | 0.042 | 0.446 | 0.53 | 0.44 | 0.048 | 0.015 | 0.51 |
K2O | 0.135 | 0.016 | 0.022 | 0.007 | 0.078 | 0.123 | 0.167 | 0 | 0.014 | 0.3 |
NiO | 0.346 | 0.34 | 0.228 | 0.315 | 0.112 | 0.391 | 0.326 | 0.231 | 0.479 | |
Na2O | 0.094 | 0.046 | 0.014 | 0.009 | 0.074 | 0.105 | 0.053 | 0.007 | 0.023 | 0.01 |
Cr2O3 | 0.063 | 0.039 | 0.065 | 0.052 | 0.005 | 0.091 | 0.018 | 0 | 0 | |
MnO | 0.188 | 0.057 | 0.142 | 0.154 | 0.15 | 0.177 | 0.252 | 0.061 | 0.026 | 0.15 |
H2O | 12.917 | 12.406 | 12.712 | 12.073 | 12.909 | 12.918 | 12.939 | 12.307 | 12.757 | 12.78 |
Total | 101.801 | 98.458 | 99.79 | 96.83 | 101.261 | 101.571 | 102.53 | 97.89 | 99.558 | 99.53 |
Serpentine, continued | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-11 89'2" |
92-11 89'2" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
|||
SiO2 | 39.19 | 45.65 | 44.18 | 48.64 | 40.97 | 41.76 | 40.53 | 45.99 | ||
TiO2 | 0.69 | 0.46 | 0.07 | 0.02 | 0.01 | 0.03 | 0.16 | 0.98 | ||
Al2O3 | 7 | 5.82 | 0.75 | 0 | 0 | 0 | 3.94 | 6.52 | ||
FeO | 10.87 | 8.4 | 6.46 | 7.88 | 4.8 | 1.46 | 6.17 | 8.07 | ||
MgO | 26.39 | 23.99 | 32.73 | 30.42 | 38.49 | 42.12 | 33.47 | 23.3 | ||
CaO | 0.12 | 0.2 | 0.39 | 0.43 | 0.18 | 0.01 | 0.08 | 0.52 | ||
K2O | 3.78 | 2.98 | 0.05 | 0.18 | 0.07 | 0.01 | 0.72 | 6.3 | ||
NiO | ||||||||||
Na2O | 0.03 | 0.08 | 0.01 | 0.18 | 0.06 | 0.02 | 0.01 | 0.13 | ||
Cr2O3 | ||||||||||
MnO | 0.07 | 0.24 | 0.21 | 0.15 | 0.05 | 0.01 | 0.15 | 0.24 | ||
H2O | 12.24 | 12.63 | 12.39 | 12.86 | 12.31 | 12.65 | 12.34 | 12.97 | ||
Total | 100.38 | 100.46 | 97.25 | 100.76 | 96.94 | 98.05 | 97.53 | 105.02 |
Olivine | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
||||||||
SiO2 | 41.43 | 41.42 | 44.37 | |||||||
MgO | 50.94 | 51.51 | 32.43 | |||||||
CaO | 0.04 | 0.05 | 0.33 | |||||||
MnO | 0.11 | 0.15 | 0.17 | |||||||
FeO | 8.45 | 8.43 | 6.59 | |||||||
Total | 100.97 | 101.56 | 83.88 |
Rutile | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
||||||||
SiO2 | 1.295 | 1.328 | 2.31 | |||||||
TiO2 | 68.077 | 69.886 | 65.84 | |||||||
Al2O3 | 0.064 | 0.031 | 0.06 | |||||||
FeO | 7.058 | 6.113 | 7.04 | |||||||
MgO | 0.075 | 0.039 | 0.48 | |||||||
CaO | 0.066 | 0.084 | 0.31 | |||||||
MnO | 0.086 | 0 | 0.07 | |||||||
Nb2O3 | 0.42 | 0.434 | 0.31 | |||||||
NiO | ||||||||||
Cr2O3 | 0 | |||||||||
ZnO | ||||||||||
Total | 77.141 | 77.915 | 76.43 |
Spinel | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
92-11 89'2" |
|||||||
SiO2 | 0.088 | 0.025 | ||||||||
TiO2 | 3.013 | 2.556 | 3.585 | 2.387 | ||||||
Al2O3 | 3.735 | 3.158 | 5.16 | 2.696 | ||||||
FeO | 15.095 | 14.843 | 15.138 | 18.749 | ||||||
Fe2O3 | 7.369 | 6.648 | 9.478 | 7.632 | ||||||
MgO | 10.87 | 10.835 | 11.037 | 7.497 | ||||||
CaO | 0 | 0 | ||||||||
MnO | 0.496 | 0.53 | 0.533 | 1.348 | ||||||
Cr2O3 | 58.272 | 59.758 | 54.664 | 57.272 | ||||||
V2O3 | 0.156 | 0.139 | ||||||||
NiO | ||||||||||
ZnO | ||||||||||
Total | 99.096 | 98.493 | 99.596 | 97.582 |
Spinel | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Eagle 4 426'6" |
Eagle 4 426'6" |
Eagle 4 426'6" |
||||||||
SiO2 | ||||||||||
TiO2 | 2.61 | 2.42 | 2.55 | |||||||
Al2O3 | 3.26 | 3.2 | 3.59 | |||||||
FeO | 16.87 | 16.02 | 15.3 | |||||||
Fe2O3 | 9.36 | 9.29 | 9.36 | |||||||
MgO | 9.39 | 10.03 | 10.53 | |||||||
CaO | ||||||||||
MnO | 0.92 | 0.95 | 0.8 | |||||||
Cr2O3 | 56.82 | 57.84 | 57.11 | |||||||
V2O3 | ||||||||||
NiO | ||||||||||
ZnO | ||||||||||
Total | 99.23 | 99.75 | 99.24 |
Feldspar | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Eagle 4 413'4" |
Eagle 4 413'4" |
|||||||||
SiO2 | 64.79 | 64.67 | ||||||||
Al2O3 | 19.91 | 19.84 | ||||||||
CaO | 0.02 | 0.03 | ||||||||
FeO | 0.19 | 0.11 | ||||||||
BaO | 0.06 | 0.11 | ||||||||
Na2O | 0.05 | 0.08 | ||||||||
K2O | 16.07 | 15.86 | ||||||||
Total | 101.1 | 100.71 |
Pyroxene | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
92-11 89'2" |
||||||
SiO2 | 53.722 | 53.628 | 53.455 | 53.42 | 52.496 | |||||
TiO2 | 1.301 | 1.283 | 1.566 | 1.44 | 1.834 | |||||
Al2O3 | 0.061 | 0.02 | 0.048 | 0.024 | 0.147 | |||||
FeO | 2.492 | 2.444 | 2.212 | 2.426 | 2.042 | |||||
Fe2O3 | 0 | 0.585 | ||||||||
MgO | 16.427 | 16.392 | 16.551 | 16.56 | 16.133 | |||||
CaO | 24.384 | 24.346 | 24.731 | 24.3 | 24.533 | |||||
MnO | 0.104 | 0.04 | 0.029 | 0.035 | 0.046 | |||||
Na2O | 0.545 | 0.554 | 0.45 | 0.419 | 0.441 | |||||
K2O | 0 | 0.032 | ||||||||
Cr2O3 | 0.496 | 0.458 | 0.385 | 0.33 | 0.359 | |||||
Total | 99.559 | 99.185 | 99.449 | 98.96 | 98.649 |
Pyroxene | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-11 89'2" |
92-11 89'2" |
|||||||||
SiO2 | 53.251 | 53.443 | ||||||||
TiO2 | 2.099 | 1.937 | ||||||||
Al2O3 | 0.126 | 0.091 | ||||||||
FeO | 2.567 | 2.032 | ||||||||
Fe2O3 | 0 | 0.208 | ||||||||
MgO | 16.346 | 16.739 | ||||||||
CaO | 24.527 | 24.814 | ||||||||
MnO | 0.07 | 0.108 | ||||||||
Na2O | 0.361 | 0.404 | ||||||||
K2O | 0.013 | 0.001 | ||||||||
Cr2O3 | 0.345 | 0.224 | ||||||||
Total | 99.705 | 100 |
Amphibole | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
92-11 89'2" |
92-11 89'2" |
||||
SiO2 | 40.573 | 52.745 | 53.885 | 55.422 | 49.637 | 50.331 | 49.968 | |||
TiO2 | 5.051 | 4.547 | 4.503 | 3.224 | 8.306 | 7.096 | 7.248 | |||
Al2O3 | 2.36 | 0.028 | 0.017 | 0.036 | 0.012 | 0.043 | 0.023 | |||
FeO | 12.789 | 4.661 | 4.493 | 3.397 | 4.943 | 4.492 | 4.65 | |||
MgO | 22.047 | 20.168 | 20.395 | 20.844 | 19.741 | 19.749 | 19.605 | |||
CaO | 0 | 6.095 | 6.007 | 6.187 | 5.838 | 5.919 | 5.995 | |||
MnO | 0.044 | 0.287 | 0.322 | 0.182 | 0.192 | 0.22 | 0.204 | |||
Na2O | 0.082 | 3.785 | 3.911 | 3.654 | 3.57 | 3.607 | 3.678 | |||
K2O | 10.136 | 5.31 | 5.254 | 5.226 | 5.329 | 5.475 | 5.483 | |||
Cr2O3 | 0.086 | 0 | 0 | 0.025 | 0.039 | 0.039 | 0 | |||
NiO | 0.119 | 0 | 0 | 0.018 | ||||||
H2O | 1.868 | 2.088 | 2.12 | 2.13 | 2.069 | 2.062 | 2.055 | |||
Total | 95.155 | 99.713 | 100.907 | 100.345 | 99.677 | 99.034 | 98.908 |
Amphibole | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-11 89'2" |
92-11 89'2" |
92-11 89'2" |
||||||||
SiO2 | 51.015 | 55.8 | 51.698 | |||||||
TiO2 | 6.886 | 2.901 | 6.326 | |||||||
Al2O3 | 0.025 | 0.164 | 0.031 | |||||||
FeO | 4.201 | 2.624 | 4.288 | |||||||
MgO | 20.031 | 21.908 | 19.845 | |||||||
CaO | 6.168 | 6.086 | 6.193 | |||||||
MnO | 0.216 | 0.068 | 0.114 | |||||||
Na2O | 3.634 | 3.909 | 3.613 | |||||||
K2O | 5.509 | 5.523 | 5.316 | |||||||
Cr2O3 | 0 | 0.037 | 0 | |||||||
NiO | ||||||||||
H2O | 2.081 | 2.152 | 2.083 | |||||||
Total | 99.765 | 101.171 | 99.505 |
Apatite | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-5 86'1" |
92-5 86'1" |
92-5 86'1" |
92-11 89'2" |
92-11 89'2" |
||||||
P2O5 | 36.824 | 40.677 | 40.502 | 41.315 | 27.69 | |||||
SiO2 | 0.674 | 0.862 | 0.876 | 0.727 | 14.83 | |||||
Y2O3 | 0.007 | 0.006 | 0.038 | 0.012 | ||||||
SO3 | ||||||||||
MgO | 0.068 | 0.045 | 0.058 | 0.078 | 5.977 | |||||
CaO | 47.749 | 52.504 | 52.78 | 52.962 | 36.193 | |||||
MnO | 0 | 0 | 0 | 0 | 0.087 | |||||
FeO | 0.388 | 0.076 | 0.092 | 0.067 | 1.483 | |||||
SrO | 5.696 | 2.491 | 2.309 | 2.344 | 4.97 | |||||
La2O3 | 0.089 | 0.499 | 0.498 | |||||||
Ce2O3 | 0.276 | 0.803 | 0.738 | 1.001 | 0.242 | |||||
Na2O | 1.075 | 0.013 | 0 | 1.772 | 1.683 | |||||
H2O | 1.617 | 1.753 | 1.756 | |||||||
Cl | 0.026 | 0.025 | 0 | |||||||
Nd2O3 | 0 | 0.555 | 0.268 | |||||||
Total | 94.432 | 100.32 | 99.898 | 100.305 | 93.166 |
Cyrkelite (Ba(Zr).Ti)Si3O9 | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-11 89'2" |
92-11 89'2" |
|||||||||
SiO2 | 38.756 | 38.67 | ||||||||
CaO | 0.005 | 0.77 | ||||||||
TiO2 | 0.468 | 1.86 | ||||||||
ZrO2 | 25.527 | 23.79 | ||||||||
HfO2 | 0.385 | 0.48 | ||||||||
BaO | 32.865 | 33.08 | ||||||||
Total | 98.006 | 98.65 |
Perovskite | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
92-11 89'2" |
92-11 89'2" |
92-11 89'2" |
92-11 89'2" |
|||||||
SiO2 | 0.01 | 0 | 1.05 | 0.03 | ||||||
TiO2 | 51.94 | 52.18 | 51.76 | 54.71 | ||||||
Al2O3 | ||||||||||
FeO | 1.2 | 1.01 | 1.08 | 0.75 | ||||||
MgO | 0.01 | 0.02 | 0.22 | 0.02 | ||||||
CaO | 32.91 | 33.48 | 35.36 | 36.39 | ||||||
Na2O | 0.46 | 0.43 | 0.57 | 0.37 | ||||||
Cr2O3 | 1.56 | 1.55 | 0.91 | 0.98 | ||||||
Nb2O3 | 0.39 | 0.43 | 0.53 | 0.37 | ||||||
ZrO2 | 0.07 | 0.1 | 0.06 | 0 | ||||||
SrO | 1.67 | 1.74 | 2.06 | 1.76 | ||||||
Ta2O5 | 0.05 | 0.02 | 0.01 | |||||||
La2O3 | 2.06 | 1.77 | 1 | 1 | ||||||
Ce2O3 | 4.92 | 4.28 | 2.09 | 2.24 | ||||||
Total | 97.23 | 97 | 96.69 | 98.64 |
Figure 2--The cationic Al and Ti compositions of clinopyroxenes from cores 92-5 and 92-11 of the Silver City Dome are compared to those of West Kimberly, Smoky Butte, Leucite Hills, Prairie Creek (Arkansas), and southeastern Spain (Mitchell and Bergman 1991).
The composition of the amphiboles of the shallow Silver City Dome cores are similar to those of the Guess core of the Silver City Dome, Smoky Butte, and West Kimberly although several samples fall outside these boundaries (fig. 3). Also the Ti concentrations are similar to those of West Kimberley (fig. 4). These amphiboles do not have the low Ti concentrations of those in the Guess and Silver City cores.
Figure 3--The composition of Na2O (weight percent) and FeO (weight percent) of 92-5 and 92-11 are compared to other lamproites (Mitchell and Bergman 1991).
Figure 4--The cationic Ti and Na/K ratios of amphiboles from cores 92-5 and 92-11 are compared to other lamproites (Mitchell and Bergman 1991).
Most of the micas from the Silver City Dome and Eagle 4 cores follow trends of decreasing FeO and Al2O3 similar to trends of the Guess Core and the Wolgidite trend at West Kimberly (fig. 5). The Ba and Ti-enriched micas rimming micas of more normal composition of core 92-5 contain very low Al2O3 and FeO contents (fig. 5, table 2). Such high Ba and Ti-rich micas have not been found in other lamproites or other types of alkalic rocks (Mitchell and Bergman, 1991). The mica TiO2 vs. the Al2O3 contents in the 92 and Eagle 4 cores follow the trend of decreasing Al2O3 at fairly constant TiO2 similar to the Guess Core (fig. 6). These trends appear to be unique for Kansas lamproites.
Figure 5--The Al2O3 and FeO compositions (weight percent) of micas from cores 92-5 and 92-11 (Silver City Dome) and Eagle 4 (Rose Dome) are compared to other lamproites (Mitchell and Bergman, 1991).
Figure 6--The Al2O3 and TiO2 composition (weight percent) of micas from cores 92-5, 92-11, and Eagle 4 are compared to other lamproites (Mitchell and Bergman, 1991).
The values of the elemental concentrations in the lamproites and associated sedimentary rocks are given in table 3. The averages and standard deviations of values of each core are given in table 4 (Cullers et al., 1985; Cullers et al., 1996); the averages and standard deviations of values at the Rose Dome and the Silver City Dome are given with similar values for other lamproites in table 5 (Jaques et al., 1984; Jaques et al., 1989; Toscani and Slavioli-Mariani, 2000; Chalapathi Rao et al., 2004).
Table 3--The composition of lamproites and associated sedimentary rocks of Woodson County.
92-5 Core-Silver City Dome | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Limestones | Lamproites | ||||||||||
Depth (feet; inches) | 63'7" | 65'1" | 65'3" | 66'1" | 70'5" | 71'7" | 74'8" | 78'2" | 81'6" | 85'6" | 86'1" |
Depth (meters) | 19.38 | 19.84 | 19.89 | 20.14 | 21.46 | 21.82 | 22.76 | 23.83 | 24.84 | 26.06 | 26.24 |
SiO2 | 19.09 | 5.69 | 48.56 | 47.51 | 48.46 | 47.76 | 44.64 | 45.45 | 44.66 | 44.51 | 46.44 |
TiO2 | 0.05 | 0.07 | 3.52 | 3.4 | 2.89 | 2.78 | 3.49 | 3.28 | 2.86 | 3.21 | 3.25 |
Al2O3 | 0.51 | 1.11 | 5.92 | 6.48 | 7.07 | 7.08 | 5.51 | 4.86 | 5.33 | 4.95 | 5.59 |
Fe2O3(total) | 2.58 | 5.14 | 7.46 | 7.96 | 7.02 | 6.78 | 8.40 | 8.58 | 7.95 | 8.21 | 8.29 |
MnO | 0.18 | 0.16 | 0.16 | 0.12 | 0.09 | 0.10 | 0.14 | 0.13 | 0.13 | 0.12 | 0.11 |
MgO | 2.21 | 3.95 | 15.09 | 17.09 | 16.49 | 16.84 | 19.2 | 22.21 | 22.35 | 22.58 | 21.91 |
CaO | 41.92 | 45.27 | 3.88 | 3.76 | 4.51 | 4.75 | 4.7 | 4.35 | 3.27 | 3.57 | 3.31 |
Na2O | 2.68 | 0.12 | 2.48 | 1.94 | 1.78 | 1.59 | 1.37 | 1.80 | 1.71 | 1.92 | 1.82 |
K2O | 0.34 | 0.10 | 6.83 | 6.84 | 7.56 | 6.91 | 5.42 | 3.68 | 4.34 | 3.8 | 3.93 |
P2O5 | 11.97 | 0.05 | 0.08 | 0.06 | 0.09 | 0.07 | 1.15 | 0.91 | 0.82 | 0.81 | 0.51 |
LOI | 17.75 | 37.85 | 4.20 | 3.60 | 3.70 | 4.46 | 4.45 | 4.25 | 5.85 | 4.55 | 4.00 |
Total | 99.45 | 99.64 | 99.32 | 99.07 | 99.90 | 99.37 | 99.00 | 99.93 | 99.99 | 99.03 | 99.82 |
Rb | 13 | 6.7 | 137 | 133 | 154 | 151 | 156 | 115 | 150 | 116 | 101 |
Ba | 887 | 268 | 10322 | 1952 | 1539 | 1348 | 2240 | 2450 | 5229 | 5804 | 4759 |
Sr | 861 | 1030 | 1050 | 1160 | 867 | 1180 | 3025 | 1810 | 1975 | 2210 | 1880 |
Th | 0.59 | 0.78 | 13.3 | 13.5 | 8.7 | 9.7 | 29.5 | 14.9 | 12.3 | 13.8 | 13.5 |
Hf | 0.26 | 0.31 | 22.6 | 22.3 | 22.4 | 21.3 | 21.1 | 19.7 | 18.8 | 19.5 | 19.9 |
Zr | 13.9 | 13.3 | 912 | 890 | 910 | 906 | 1106 | 841 | 739 | 801 | 804 |
Ta | 0.04 | 0.08 | 4.6 | 4.5 | 3.7 | 3.4 | 4.4 | 4.2 | 3.7 | 3.8 | 4.0 |
Co | 2.9 | 5.0 | 42.2 | 44.4 | 46.1 | 42.8 | 49.2 | 52.2 | 59.2 | 58.1 | 53.5 |
Sc | 4.1 | 3.4 | 15.7 | 14.9 | 52.6 | 13.3 | 14.5 | 13.5 | 11.4 | 14.0 | 14 |
Ni | 19 | 25.8 | 524 | 581 | 640 | 578 | 714 | 754 | 875 | 845 | 743 |
Cr | 889 | 958 | 889 | 958 | 899 | 1160 | 1170 | 1070 | 1070 | ||
U | 2.06 | 3.91 | 2.82 | 2.62 | 2.38 | 1.72 | 3.5 | 4.19 | 2.83 | 2.94 | 2.8 |
Y | 5.2 | 5.0 | 17.5 | 16.4 | 13.5 | 13.4 | 13.6 | 19.4 | 14.1 | 16.0 | 15.3 |
Nb | 0.95 | 1.1 | 94 | 95 | 66 | 52 | 90 | 93 | 74 | 83 | 79 |
La | 3.0 | 2.9 | 170 | 177 | 146 | 132 | 219 | 221 | 202 | 208 | 198 |
Ce | 6.5 | 6.0 | 313 | 347 | 318 | 264 | 448 | 452 | 375 | 402 | 388 |
Pr | 0.77 | 0.8 | 33.5 | 39.0 | 37.8 | 30.5 | 49.1 | 51.2 | 40.5 | 43.0 | 42.5 |
Nd | 3.1 | 3.2 | 109 | 127 | 128 | 102 | 158 | 171 | 137 | 149 | 142 |
Sm | 0.68 | 0.77 | 16.2 | 15.2 | 13.8 | 12.0 | 15.1 | 20 | 14.4 | 16.0 | 15.8 |
Eu | 0.57 | 0.27 | 8.09 | 4.05 | 3.48 | 3.10 | 3.17 | 4.87 | 2.90 | 3.18 | 3.05 |
Gd | 0.71 | 0.77 | 9.95 | 9.23 | 8.26 | 7.49 | 9.54 | 12.3 | 9.79 | 10.3 | 9.94 |
Tb | 0.11 | 0.11 | 1.27 | 1.21 | 1.07 | 1.21 | 1.17 | 1.47 | 1.22 | 1.25 | 1.26 |
Dy | 0.59 | 0.68 | 4.34 | 3.95 | 3.30 | 3.42 | 3.35 | 4.58 | 3.43 | 3.86 | 3.71 |
Ho | 0.13 | 0.12 | 0.70 | 0.64 | 0.54 | 0.52 | 0.56 | 0.8 | 0.55 | 0.66 | 0.58 |
Er | 0.29 | 0.34 | 1.69 | 1.47 | 1.26 | 1.25 | 1.24 | 1.68 | 1.33 | 1.49 | 1.48 |
Tm | 0.18 | 0.18 | 0.19 | 0.19 | |||||||
Yb | 0.28 | 0.25 | 1.30 | 1.18 | 0.91 | 0.83 | 1.30 | 1.28 | 1.10 | 1.30 | 1.20 |
Lu | 0.040 | 0.030 | 0.20 | 0.18 | 0.14 | 0.13 | 0.17 | 0.2 | 0.16 | 0.16 | 0.16 |
Cu | 6.7 | 10.7 | 58.5 | 63.3 | 52.4 | 36.6 | 58.7 | 56.5 | 44.8 | 47.4 | 50 |
Li | 46 | 30 | 32 | 35 | |||||||
Zn | 6.6 | 20.2 | 70.4 | 80 | 59 | 62.7 | 92 | 87.5 | 70 | 71.9 | 80 |
Cs | 0.20 | 0.11 | 0.25 | 0.28 | 0.37 | 0.45 | 0.29 | 0.24 | 0.50 | 0.30 | 0.22 |
Ga | 4.5 | 7.1 | 15.4 | 17.4 | 16.6 | 15.9 | 17.5 | 18.0 | 14.0 | 14.4 | 15.5 |
Ge | 2 | 1 | 1 | 1 | |||||||
Pb | 6.1 | 3.7 | 41.0 | 41.7 | 27.0 | 8.3 | 42.2 | 44.4 | 40.6 | 42.4 | 37.3 |
V | 342 | 32.3 | 197 | 112 | 77.7 | 56.8 | 79 | 49.2 | 42.8 | 45 | 38.6 |
K2O/Na2O | 0.13 | 0.83 | 2.75 | 3.53 | 4.25 | 4.35 | 3.96 | 2.04 | 2.54 | 1.98 | 2.16 |
(K2O+Na2O)/Al2O3 | 9.37 | 0.28 | 1.94 | 1.64 | 1.57 | 1.43 | 1.47 | 1.43 | 1.41 | 1.47 | 1.30 |
Mg# | 0.485 | 0.458 | 0.690 | 0.703 | 0.721 | 0.732 | 0.715 | 0.740 | 0.756 | 0.752 | 0.744 |
92-5 Core-Sliver City Dome | |||||||
---|---|---|---|---|---|---|---|
Lamproites | Limestone | Altered carbonate shale |
|||||
Depth (feet; inches) | 91'5" | 92'4" | 96'1" | 99'8" | 103'6" | 107'1" | 109'4" |
Depth (meters) | 27.86 | 28.14 | 29.29 | 30.38 | 31.55 | 32.64 | 33.32 |
SiO2 | 44.86 | 44.97 | 44.4 | 45.64 | 46.58 | 11.18 | 40.21 |
TiO2 | 3.17 | 2.96 | 3.55 | 3.4 | 3.34 | 0.03 | 0.76 |
Al2O3 | 5.22 | 5.11 | 5.98 | 5.82 | 5.68 | 0.33 | 13.89 |
Fe2O3(total) | 7.67 | 7.75 | 7.07 | 7.72 | 7.22 | 4.64 | 5.07 |
MnO | 0.11 | 0.11 | 0.13 | 0.10 | 0.14 | 0.24 | 0.09 |
MgO | 20.94 | 22.79 | 12.84 | 18.88 | 18.38 | 3.99 | 7.62 |
CaO | 3.58 | 3.2 | 9.44 | 4.21 | 3.33 | 42.1 | 13.29 |
Na2O | 1.66 | 1.61 | 2.44 | 1.83 | 1.66 | 0.77 | 1.34 |
K2O | 4.54 | 4.27 | 5.11 | 5.52 | 5.19 | 0.06 | 5.27 |
P2O5 | 0.71 | 0.45 | 2.78 | 1.31 | 1.11 | 0.13 | 0.1 |
LOI | 5.55 | 5.00 | 4.93 | 4.11 | 5.5 | 35.85 | 12.25 |
Total | 99.05 | 99.07 | 99.09 | 99.02 | 99.28 | 99.42 | 100.03 |
Rb | 112 | 128 | 69 | 97 | 118 | 3 | 189 |
Ba | 8220 | 6890 | 1558 | 3400 | 9732 | 112 | 539 |
Sr | 2170 | 1560 | 2600 | 1400 | 1760 | 881 | 819 |
Th | 12.7 | 10.2 | 17.1 | 11.7 | 10.3 | 0.38 | 7.7 |
Hf | 18.9 | 17.4 | 22.3 | 21.9 | 20.2 | 0.16 | 2.68 |
Zr | 742 | 687 | 899 | 880 | 803 | 5.4 | 112 |
Ta | 3.6 | 3.2 | 3.9 | 4.1 | 3.6 | 0.04 | 1.06 |
Co | 55.6 | 58.5 | 39.2 | 44.6 | 50.6 | 2.4 | 14.7 |
Sc | 14.6 | 13.3 | 14.5 | 14.3 | 13.3 | 2.43 | 12.8 |
Ni | 794 | 925 | 344 | 620 | 838 | 15 | 48.7 |
Cr | 1020 | 1160 | 772 | 1094 | 895 | 6 | 111 |
U | 2.7 | 2.57 | 5.2 | 2.65 | 2.45 | 1.68 | 3.12 |
Y | 14.9 | 12.5 | 25.4 | 23.4 | 17.8 | 4.0 | 14.2 |
Nb | 76 | 62 | 82 | 84 | 76 | 0.64 | 17.6 |
La | 197 | 147 | 196 | 176 | 167 | 2.6 | 28.8 |
Ce | 381 | 299 | 423 | 335 | 291 | 5.3 | 46.3 |
Pr | 42.2 | 34.4 | 52.3 | 36.6 | 30.9 | 0.6 | 5.3 |
Nd | 144 | 121 | 203 | 119 | 106 | 2.4 | 19.8 |
Sm | 15.2 | 14.1 | 29.8 | 17.1 | 12.4 | 0.49 | 3.7 |
Eu | 2.88 | 2.67 | 6.80 | 5.29 | 2.04 | 0.16 | 0.85 |
Gd | 10.1 | 9.23 | 18.0 | 11.3 | 8.38 | 0.53 | 3.0 |
Tb | 1.24 | 1.05 | 2.06 | 1.45 | 1.17 | 0.079 | 0.44 |
Dy | 3.61 | 3.09 | 6.12 | 5.33 | 4.21 | 0.49 | 2.23 |
Ho | 0.60 | 0.52 | 1.04 | 0.89 | 0.68 | 0.11 | 0.39 |
Er | 1.41 | 1.13 | 2.17 | 2.08 | 1.71 | 0.29 | 1.25 |
Tm | 0.18 | 0.14 | 0.27 | 0.19 | |||
Yb | 1.20 | 1.00 | 1.60 | 1.40 | 1.15 | 0.27 | 1.25 |
Lu | 0.13 | 0.13 | 0.21 | 0.19 | 0.15 | 0.05 | 0.19 |
Cu | 49.2 | 44.2 | 54.9 | 64.8 | 25 | 2.3 | 15.0 |
Li | 40 | 37 | 95 | 61 | |||
Zn | 71.4 | 74.4 | 64 | 76.1 | 61 | 5.2 | 65.9 |
Cs | 0.19 | 0.25 | 0.16 | 0.17 | 0.27 | 0.083 | 9.5 |
Ga | 17.2 | 14.8 | 15.7 | 15.3 | 15.8 | 1.33 | 18.3 |
Ge | 1 | 1 | 1 | 2 | |||
Pb | 36.0 | 31.8 | 58.2 | 38.7 | 35.6 | 2.0 | 5.8 |
V | 94 | 68 | 129 | 146 | 131 | 18.1 | 113 |
K2O/Na2O | 2.73 | 2.65 | 2.09 | 3.02 | 3.13 | 0.08 | 3.93 |
(K2O+Na2O)/Al2O3 | 1.46 | 1.42 | 1.60 | 1.54 | 1.47 | 4.04 | 0.57 |
Mg# | 0.750 | 0.764 | 0.666 | 0.729 | 0.737 | 0.486 | 0.623 |
92-11 Core-Silver City Dome | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Limestones | Lamproites | |||||||||
Depth (feet; inches) | 58'3" | 60'5" | 61'3" | 62'0" | 65'4" | 69'11" | 74'2" | 78'4" | 79'10" | 84'7" |
Depth (meters) | 17.68 | 18.42 | 18.67 | 18.90 | 19.91 | 21.31 | 22.61 | 23.88 | 24.33 | 25.78 |
SiO2 | 1.6 | 1.74 | 5.88 | 49.7 | 45.95 | 44.84 | 44.96 | 42.88 | 41.88 | 41.75 |
TiO2 | 0.04 | 0.03 | 0.08 | 4.24 | 3.38 | 3.66 | 3.59 | 2.42 | 2.48 | 2.16 |
Al2O3 | 0.28 | 0.38 | 0.56 | 8.24 | 6.04 | 5.63 | 7.96 | 4.00 | 3.66 | 3.64 |
Fe2O3(total) | 2.26 | 0.41 | 0.59 | 7.9 | 8.09 | 8.38 | 7.79 | 7.93 | 8.12 | 8.03 |
MnO | 0.07 | 0.03 | 0.05 | 0.10 | 0.13 | 0.13 | 0.10 | 0.14 | 0.12 | 0.13 |
MgO | 3.01 | 1.28 | 1.04 | 12.45 | 18.87 | 19.61 | 15.97 | 26.21 | 27.95 | 29.04 |
CaO | 50.93 | 53.44 | 51.21 | 3.83 | 3.93 | 3.78 | 4.04 | 3.09 | 2.84 | 2.50 |
Na2O | 0.02 | 0.03 | 0.58 | 1.15 | 1.88 | 1.76 | 0.85 | 1.09 | 0.85 | 0.67 |
K2O | 0.03 | 0.05 | 0.14 | 8.40 | 5.75 | 5.37 | 8.59 | 3.82 | 2.97 | 2.70 |
P2O5 | 0.03 | 0.04 | 0.6 | 0.03 | 0.44 | 0.28 | 1.14 | 0.98 | 0.77 | 0.66 |
LOI | 40.95 | 42.7 | 38.75 | 3.15 | 4.13 | 5.15 | 3.95 | 6.15 | 7.09 | 7.6 |
Total | 99.34 | 100.26 | 99.66 | 99.41 | 99.01 | 99.41 | 99.32 | 99.36 | 99.27 | 99.39 |
Rb | 0.6 | 5.6 | 14.2 | 137 | 133 | 127 | 246 | 169 | 136 | 133 |
Ba | 45 | 29 | 91 | 1447 | 2190 | 6590 | 2369 | 4289 | 3357 | 3147 |
Sr | 1120 | 1250 | 1680 | 718 | 2030 | 1615 | 1430 | 2260 | 2050 | 2000 |
Th | 0.23 | 0.21 | 0.44 | 8.2 | 15.1 | 16.1 | 12.3 | 11.2 | 11.0 | 9.6 |
Hf | 0.11 | 0.15 | 0.22 | 26.8 | 21.9 | 23.4 | 26.6 | 14.8 | 13.8 | 12.5 |
Zr | 8.2 | 5.5 | 5.9 | 1067 | 873 | 896 | 1073 | 598 | 560 | 548 |
Ta | 0.03 | 0.03 | 0.06 | 5.0 | 4.3 | 4.5 | 6.0 | 3.3 | 3.1 | 2.7 |
Co | 2.5 | 1.8 | 2.1 | 41.2 | 49.3 | 54.2 | 39.5 | 65.9 | 67.2 | 72.6 |
Sc | 2.3 | 2.7 | 3.1 | 16.4 | 14.3 | 14.6 | 19.7 | 10.4 | 10.6 | 10.1 |
Ni | 21.3 | 15.4 | 15.6 | 331 | 687 | 680 | 405 | 1071 | 1114 | 1278 |
Cr | 5.4 | 4.0 | 6.7 | 788 | 1026 | 995 | 821 | 1140 | 1020 | 1150 |
U | 2.85 | 0.88 | 1.5 | 2.38 | 2.84 | 3.3 | 2.37 | 2.09 | 2.4 | 2.0 |
Y | 1.1 | 1.4 | 1.9 | 12.5 | 17.2 | 18.5 | 19.7 | 13.1 | 13.3 | 11.4 |
Nb | 0.4 | 0.4 | 0.9 | 99 | 93 | 96 | 100 | 69 | 70 | 60 |
La | 0.89 | 0.94 | 2.03 | 209 | 177 | 229 | 191 | 172 | 157 | 141 |
Ce | 1.88 | 1.93 | 4.23 | 388 | 360 | 451 | 399 | 327 | 304 | 275 |
Pr | 0.22 | 0.24 | 0.52 | 39.9 | 41.3 | 47.8 | 45.7 | 35.0 | 32.7 | 29.9 |
Nd | 0.94 | 0.93 | 1.99 | 124 | 137 | 161 | 149 | 118 | 110 | 99.5 |
Sm | 0.17 | 0.20 | 0.35 | 11.3 | 16.0 | 17.9 | 16.5 | 13.1 | 12.3 | 11.3 |
Eu | 0.05 | 0.05 | 0.09 | 2.16 | 4.18 | 3.44 | 4.43 | 2.64 | 2.44 | 2.20 |
Gd | 0.18 | 0.19 | 0.34 | 7.43 | 9.56 | 11.5 | 10.5 | 8.58 | 8.06 | 7.08 |
Tb | 0.03 | 0.03 | 0.05 | 0.93 | 1.25 | 1.46 | 1.40 | 1.01 | 1.03 | 0.89 |
Dy | 0.15 | 0.17 | 0.26 | 2.35 | 4.16 | 4.50 | 4.73 | 2.90 | 3.26 | 2.73 |
Ho | 0.03 | 0.04 | 0.05 | 0.44 | 0.66 | 0.76 | 0.82 | 0.50 | 0.51 | 0.44 |
Er | 0.06 | 0.13 | 0.14 | 1.24 | 1.59 | 1.84 | 1.86 | 1.13 | 1.21 | 1.11 |
Tm | 0.19 | 0.23 | 0.14 | 0.16 | 0.15 | |||||
Yb | 0.07 | 0.13 | 0.13 | 1.29 | 1.27 | 1.50 | 1.55 | 0.99 | 1.10 | 0.90 |
Lu | 0.01 | 0.02 | 0.02 | 0.16 | 0.18 | 0.19 | 0.23 | 0.11 | 0.13 | 0.13 |
Cu | 3.2 | 0.01 | 0.01 | 75.3 | 60.6 | 55.9 | 80.8 | 41.2 | 43.1 | 37.7 |
Li | 22 | 18 | 42 | 46 | 40 | |||||
Zn | 6.3 | 1.0 | 4.1 | 81 | 79.7 | 75.6 | 87.3 | 62.2 | 68.3 | 77.7 |
Cs | 0.02 | 0.11 | 0.22 | 0.21 | 0.32 | 0.29 | 0.69 | 1.26 | 1.1 | 1.07 |
Ga | 3.0 | 1.0 | 0.72 | 17.7 | 16.1 | 17 | 18.9 | 9.9 | 10.6 | 9.6 |
Ge | 2 | 1 | 1 | 1 | 1 | |||||
Pb | 2.0 | 0.57 | 2.5 | 29.8 | 41.9 | 51.8 | 7.4 | 24.3 | 34.6 | 27.2 |
V | 20.4 | 21.9 | 31.6 | 168 | 136 | 96 | 25.1 | 32.3 | 29.7 | 30.4 |
K2O/Na2O | 1.50 | 1.67 | 0.24 | 7.30 | 3.06 | 3.05 | 10.11 | 3.50 | 3.49 | 4.03 |
(K2O+Na2O)/Al2O3 | 0.23 | 0.27 | 1.97 | 1.33 | 1.54 | 1.55 | 1.34 | 1.48 | 1.26 | 1.11 |
Mg# | 0.594 | 0.774 | 0.660 | 0.634 | 0.720 | 0.720 | 0.693 | 0.784 | 0.791 | 0.799 |
92-11 Core-Silver City Dome | |||||||
---|---|---|---|---|---|---|---|
Lamproites | |||||||
Depth (feet; inches) | 89'2" | 91'10" | 96'2" | 102'1" | 105'5" | 108'9" | 114'6" |
Depth (meters) | 27.18 | 27.99 | 29.31 | 31.12 | 32.13 | 33.15 | 34.90 |
SiO2 | 42.66 | 43.41 | 43.57 | 43.25 | 44.19 | 44.82 | 45.06 |
TiO2 | 2.00 | 2.3 | 2.56 | 2.45 | 2.51 | 2.86 | 3.49 |
Al2O3 | 3.84 | 4.86 | 4.63 | 4.68 | 4.58 | 5.19 | 5.62 |
Fe2O3(total) | 7.93 | 7.72 | 7.6 | 7.49 | 7.58 | 7.56 | 8.04 |
MnO | 0.12 | 0.11 | 0.10 | 0.13 | 0.12 | 0.12 | 0.12 |
MgO | 28.43 | 26.07 | 25.9 | 26.14 | 25.88 | 22.74 | 19.19 |
CaO | 2.76 | 2.29 | 3.30 | 2.93 | 2.48 | 2.97 | 4.75 |
Na2O | 0.87 | 1.21 | 1.32 | 1.21 | 1.39 | 1.18 | 2.01 |
K2O | 3.09 | 4.98 | 4.00 | 3.47 | 3.69 | 4.95 | 4.70 |
P2O5 | 0.79 | 0.50 | 0.81 | 0.61 | 0.30 | 0.64 | 0.97 |
LOI | 7.00 | 5.30 | 5.25 | 6.25 | 6.22 | 5.62 | 5.12 |
Total | 99.94 | 99.37 | 99.63 | 99.25 | 99.57 | 99.55 | 99.42 |
Rb | 132 | 193 | 126 | 151 | 143 | 163 | 100 |
Ba | 2130 | 4752 | 2396 | 4412 | 4465 | 6810 | 1732 |
Sr | 2330 | 1430 | 3460 | 2020 | 1800 | 2140 | 1730 |
Th | 7.0 | 9.8 | 8.7 | 9.9 | 9.7 | 11.6 | 14.4 |
Hf | 12.7 | 14.9 | 17 | 14.1 | 14.2 | 17.8 | 24.1 |
Zr | 569 | 582 | 707 | 577 | 577 | 702 | 1000 |
Ta | 2.6 | 2.8 | 3.0 | 2.9 | 2.6 | 3.1 | 4.3 |
Co | 64.8 | 66 | 60.2 | 63.2 | 64.6 | 56.6 | 52.4 |
Sc | 10.6 | 10.4 | 12.3 | 10.7 | 10.5 | 12.5 | 15.6 |
Ni | 1222 | 1040 | 1070 | 1145 | 1133 | 903 | 736 |
Cr | 1640 | 961 | 1230 | 977 | 1050 | 916 | 1026 |
U | 1.19 | 1.41 | 1.48 | 2.25 | 2.17 | 2.54 | 2.94 |
Y | 9.6 | 12.1 | 10.6 | 11.5 | 11.2 | 13.5 | 17.4 |
Nb | 51 | 56 | 55 | 59 | 59 | 67 | 90 |
La | 123 | 144 | 150 | 156 | 156 | 177 | 187 |
Ce | 244 | 285 | 290 | 291 | 307 | 340 | 381 |
Pr | 27.2 | 32.4 | 32.3 | 31.9 | 33.6 | 37.0 | 43.8 |
Nd | 89 | 111 | 106 | 106 | 115 | 127 | 144 |
Sm | 10.4 | 12.4 | 11.9 | 11.9 | 12.5 | 14.3 | 16.3 |
Eu | 2.98 | 2.24 | 3.52 | 2.33 | 2.37 | 2.78 | 3.95 |
Gd | 5.81 | 7.82 | 7.02 | 7.64 | 7.89 | 9.29 | 9.72 |
Tb | 0.78 | 0.98 | 0.89 | 0.93 | 0.93 | 1.14 | 1.29 |
Dy | 2.18 | 3.05 | 2.59 | 2.71 | 2.59 | 3.37 | 4.14 |
Ho | 0.33 | 0.49 | 0.40 | 0.44 | 0.42 | 0.54 | 0.66 |
Er | 0.83 | 1.09 | 0.93 | 1.02 | 0.94 | 1.31 | 1.59 |
Tm | 0.13 | 0.13 | 0.14 | 0.17 | |||
Yb | 0.66 | 0.90 | 0.76 | 0.90 | 0.90 | 1.10 | 1.25 |
Lu | 0.09 | 0.11 | 0.12 | 0.12 | 0.11 | 0.16 | 0.17 |
Cu | 48.3 | 28 | 48.5 | 40.0 | 38.2 | 45.4 | 61.7 |
Li | 35 | 34 | 29 | 28 | |||
Zn | 66.4 | 62.6 | 63.9 | 58.3 | 76.9 | 64.9 | 77.9 |
Cs | 0.76 | 0.98 | 0.86 | 0.86 | 0.72 | 0.57 | 0.25 |
Ga | 10.8 | 13.0 | 12.7 | 11.4 | 12.9 | 14.3 | 17.8 |
Ge | 1 | 1 | 1 | 1 | |||
Pb | 18.0 | 20.1 | 14.7 | 28.7 | 28.7 | 34.7 | 50.1 |
V | 30.2 | 46.3 | 30.8 | 41.4 | 46.1 | 64.6 | 128 |
K2O/Na2O | 3.55 | 4.12 | 3.03 | 2.87 | 2.65 | 4.19 | 2.34 |
(K2O+Na2O)/Al2O3 | 1.24 | 1.52 | 1.40 | 1.23 | 1.37 | 1.41 | 1.49 |
Mg# | 0.798 | 0.788 | 0.789 | 0.793 | 0.790 | 0.768 | 0.724 |
92-10 Core-Silver City Dome | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Limestones | Lamproites | |||||||||
Depth (feet; inches) | 28'3" | 29'8" | 30'6" | 32'10" | 37'5" | 40'6" | 45'3" | 48'6" | 51'4" | 55'0" |
Depth (meters) | 8.61 | 9.04 | 9.30 | 10.01 | 11.40 | 12.34 | 13.79 | 14.78 | 15.65 | 16.76 |
SiO2 | 1.83 | 1.95 | 45.65 | 48.22 | 42.49 | 44.64 | 44.62 | 43.22 | 44.39 | 43.03 |
TiO2 | 0.03 | 0.06 | 3.94 | 3.74 | 3.58 | 4.36 | 3.14 | 3.03 | 3.00 | 2.34 |
Al2O3 | 0.39 | 0.53 | 5.37 | 6.12 | 7.3 | 6.98 | 6.39 | 5.68 | 5.37 | 3.91 |
Fe2O3(total) | 0.41 | 0.44 | 8.40 | 8.48 | 8.39 | 9.07 | 7.91 | 7.95 | 7.90 | 8.16 |
MnO | 0.04 | 0.03 | 0.10 | 0.08 | 0.08 | 0.09 | 0.11 | 0.10 | 0.12 | 0.19 |
MgO | 0.49 | 0.72 | 14.59 | 16.25 | 17.83 | 15.86 | 19.74 | 22.00 | 21.55 | 26.91 |
CaO | 54.32 | 53.67 | 6.59 | 4.12 | 4.87 | 4.89 | 4.15 | 3.93 | 3.72 | 2.95 |
Na2O | 0.02 | 0.03 | 0.70 | 0.66 | 0.72 | 0.75 | 0.87 | 0.93 | 0.82 | 0.58 |
K2O | 0.06 | 0.06 | 4.55 | 5.49 | 6.42 | 5.90 | 5.29 | 4.81 | 5.07 | 3.37 |
P2O5 | 0.05 | 0.08 | 2.03 | 2.07 | 2.06 | 2.24 | 2.29 | 1.99 | 1.72 | 1.28 |
LOI | 42.25 | 42.2 | 6.80 | 4.46 | 4.95 | 4.34 | 4.13 | 4.95 | 4.89 | 6.45 |
Total | 100.04 | 100.00 | 99.14 | 100.12 | 99.03 | 99.53 | 99.09 | 99.12 | 99.19 | 99.65 |
Rb | 4 | 3.0 | 102 | 132 | 156 | 130 | 123 | 124 | 147 | 133 |
Ba | 311 | 1041 | 2434 | 2610 | 1790 | 2310 | 2535 | 3050 | 4270 | 2890 |
Sr | 1200 | 1290 | 1740 | 1690 | 1570 | 1830 | 2010 | 2250 | 2150 | 1900 |
Th | 0.35 | 0.39 | 16.0 | 14.8 | 15.3 | 20.2 | 16.9 | 11.7 | 12.3 | 11.1 |
Hf | 0.13 | 0.21 | 18.8 | 20.4 | 20.4 | 24.1 | 18.9 | 18.2 | 18.4 | 14.3 |
Zr | 4.4 | 9.0 | 74 | 781 | 826 | 1096 | 803 | 737 | 704 | 580 |
Ta | 0.03 | 0.06 | 5.6 | 4.6 | 3.8 | 5.5 | 4.4 | 4.0 | 3.8 | 3.2 |
Co | 1.7 | 2.1 | 38.7 | 43.8 | 49.1 | 50.1 | 53.2 | 47.9 | 54.1 | 72.0 |
Sc | 2.5 | 2.6 | 14.4 | 13.6 | 15.2 | 19.2 | 13.7 | 14.8 | 13.3 | 10.8 |
Ni | 14.9 | 13.7 | 433 | 515 | 539 | 409 | 691 | 714 | 770 | 1243 |
Cr | 684 | 1230 | 1090 | 930 | 1290 | 1300 | 1180 | 833 | ||
U | 1.19 | 1.2 | 2.34 | 2.25 | 3.3 | 4.9 | 3.4 | 3.25 | 2.8 | 2.3 |
Y | 3.2 | 2.4 | 15.0 | 15.9 | 17.1 | 22.4 | 20.6 | 16.4 | 14.6 | 13.4 |
Nb | 0.45 | 0.9 | 117 | 88 | 89 | 127 | 90 | 70 | 86 | 70 |
La | 2.0 | 2.1 | 220 | 227 | 200 | 261 | 227 | 164 | 180 | 160 |
Ce | 3.7 | 3.3 | 427 | 452 | 379 | 476 | 438 | 324 | 341 | 306 |
Pr | 0.51 | 0.41 | 47.8 | 51.6 | 41.1 | 51.9 | 47.5 | 36.4 | 37.7 | 33.1 |
Nd | 1.9 | 1.5 | 153 | 169 | 138 | 175 | 163 | 120 | 129 | 112 |
Sm | 0.37 | 0.31 | 17.0 | 18.8 | 14.1 | 20.0 | 18.2 | 13.6 | 14.5 | 12.2 |
Eu | 0.20 | 0.42 | 4.52 | 4.33 | 3.04 | 4.34 | 3.96 | 4.05 | 2.99 | 2.60 |
Gd | 0.39 | 0.30 | 10.3 | 11.3 | 9.62 | 13.1 | 12.0 | 8.32 | 9.67 | 8.01 |
Tb | 0.065 | 0.050 | 1.33 | 1.44 | 1.24 | 1.60 | 1.46 | 1.10 | 1.20 | 1.00 |
Dy | 0.36 | 0.29 | 3.93 | 4.13 | 3.65 | 5.19 | 4.85 | 3.53 | 3.63 | 3.06 |
Ho | 0.076 | 0.059 | 0.61 | 0.64 | 0.63 | 0.84 | 0.81 | 0.62 | 0.59 | 0.50 |
Er | 0.22 | 0.18 | 1.37 | 1.42 | 1.59 | 1.99 | 1.91 | 1.56 | 1.34 | 1.22 |
Tm | 0.21 | 0.26 | 0.23 | 0.16 | 0.15 | |||||
Yb | 0.18 | 0.18 | 1.07 | 1.08 | 1.50 | 1.8 | 1.40 | 1.33 | 1.00 | 1.00 |
Lu | 0.03 | 0.03 | 0.15 | 0.16 | 0.17 | 0.23 | 0.21 | 0.19 | 0.11 | 0.11 |
Cu | 0.13 | 5.1 | 82.7 | 69.6 | 54.0 | 83.0 | 53.0 | 44.5 | 49.3 | 40.2 |
Li | 30 | 21 | 24 | 41 | 71 | |||||
Zn | 9.1 | 13 | 85.8 | 83.8 | 71.3 | 95 | 70 | 71 | 71.3 | 70 |
Cs | 0.02 | 0.02 | 0.21 | 0.25 | 0.25 | 0.38 | 0.39 | 0.35 | 0.46 | 0.65 |
Ga | 0.44 | 2.2 | 16.1 | 18.6 | 16.3 | 18.7 | 15.0 | 16.5 | 13.7 | 10.4 |
Ge | 1 | 1 | 1 | 1 | 1 | |||||
Pb | 1.6 | 2.6 | 24.6 | 37.0 | 46.9 | 60.3 | 46.4 | 26.4 | 36.6 | 32.0 |
V | 14 | 13.4 | 131 | 64 | 140 | 177 | 146 | 235 | 72 | 58 |
K2O/Na2O | 3.00 | 2.00 | 6.50 | 8.32 | 8.92 | 7.87 | 6.08 | 5.17 | 6.18 | 5.81 |
(K2O+Na2O)/Al2O3 | 0.25 | 0.22 | 1.13 | 1.15 | 1.11 | 1.09 | 1.12 | 1.19 | 1.27 | 1.18 |
Mg# | 0.568 | 0.643 | 0.656 | 0.678 | 0.700 | 0.658 | 0.733 | 0.753 | 0.750 | 0.784 |
92-10 Core-Silver City Dome | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Lamproites | Limestones | ||||||||||
Depth (feet; inches) | 57'2" | 60'3" | 64'7" | 67'2" | 70'8" | 71'11" | 72'4" | 74'6" | |||
Depth (meters) | 17.42 | 18.36 | 19.69 | 20.47 | 21.54 | 21.92 | 22.05 | 22.71 | |||
SiO2 | 42.21 | 42.43 | 42.51 | 42.94 | 43.23 | 41.75 | 1.37 | 1.5 | |||
TiO2 | 2.32 | 2.34 | 2.25 | 2.30 | 2.66 | 3.20 | 0.02 | 0.02 | |||
Al2O3 | 4.43 | 3.91 | 3.86 | 3.87 | 5.02 | 5.65 | 0.23 | 0.08 | |||
Fe2O3(total) | 7.84 | 7.96 | 7.99 | 7.86 | 7.76 | 6.43 | 0.36 | 0.64 | |||
MnO | 0.14 | 0.15 | 0.15 | 0.14 | 0.12 | 0.08 | 0.03 | 0.04 | |||
MgO | 27.43 | 27.9 | 28.09 | 27.64 | 26.11 | 24.43 | 1.04 | 1.2 | |||
CaO | 2.94 | 2.62 | 2.44 | 2.38 | 2.76 | 5.56 | 53.61 | 53.19 | |||
Na2O | 0.61 | 0.51 | 0.55 | 0.64 | 0.9 | 1.33 | 0.03 | 0.03 | |||
K2O | 3.63 | 3.39 | 3.23 | 3.57 | 3.85 | 2.16 | 0.03 | 0.03 | |||
P2O5 | 1.17 | 0.99 | 0.97 | 0.85 | 0.92 | 2.31 | 0.05 | 0.03 | |||
LOI | 6.30 | 6.95 | 6.90 | 6.50 | 5.70 | 5.85 | 42.7 | 42.65 | |||
Total | 99.53 | 99.69 | 99.42 | 99.18 | 99.39 | 99.12 | 99.59 | 99.53 | |||
Rb | 132 | 118 | 119 | 108 | 118 | 44 | 3.1 | 3.1 | |||
Ba | 3190 | 3520 | 2810 | 3074 | 1525 | 756 | 31 | 51 | |||
Sr | 1940 | 1850 | 1990 | 1840 | 2110 | 2950 | 1210 | 1170 | |||
Th | 9.9 | 9.9 | 9.2 | 9.1 | 10.6 | 9.2 | 0.26 | 0.11 | |||
Hf | 13.6 | 13.9 | 14.1 | 13.8 | 16.7 | 19.6 | 0.08 | 0.08 | |||
Zr | 554 | 567 | 590 | 559 | 670 | 830 | 1.9 | 5.2 | |||
Ta | 2.9 | 2.9 | 2.6 | 2.7 | 3.1 | 3.5 | 0.03 | 0.02 | |||
Co | 66.2 | 75.2 | 72.3 | 72.7 | 53.0 | 24.2 | 1.9 | 2.6 | |||
Sc | 10.2 | 10.5 | 9.8 | 10.0 | 11.3 | 14.0 | 2.4 | 2.2 | |||
Ni | 1086 | 1350 | 1313 | 1317 | 890 | 171 | 16.9 | 24.5 | |||
Cr | 1190 | 1180 | 994 | 898 | 1300 | 547 | 5.3 | 4.1 | |||
U | 2.0 | 2.1 | 2.0 | 1.9 | 2.14 | 2.14 | 1.45 | 1.01 | |||
Y | 11.2 | 12.4 | 11.7 | 11.8 | 14.2 | 16.0 | 1.5 | 0.9 | |||
Nb | 59 | 62 | 59 | 56 | 70 | 78 | 0.32 | 0.29 | |||
La | 147 | 154 | 151 | 141 | 149 | 229 | 1.2 | 0.84 | |||
Ce | 284 | 296 | 294 | 271 | 303 | 519 | 2.2 | 1.6 | |||
Pr | 31.1 | 32.7 | 31.3 | 29.6 | 34.7 | 62.6 | 0.3 | 0.2 | |||
Nd | 104 | 110 | 106 | 98.1 | 114 | 198 | 1.1 | 0.71 | |||
Sm | 11.4 | 12.0 | 11.5 | 10.8 | 13.0 | 20.0 | 0.22 | 0.11 | |||
Eu | 2.36 | 2.46 | 2.31 | 2.21 | 3.35 | 4.43 | 0.05 | 0.05 | |||
Gd | 7.43 | 7.68 | 7.48 | 7.21 | 7.86 | 12.1 | 0.21 | 0.10 | |||
Tb | 0.91 | 0.94 | 0.94 | 0.90 | 1.03 | 1.57 | 0.03 | 0.01 | |||
Dy | 2.75 | 2.82 | 2.84 | 2.80 | 3.20 | 4.15 | 0.19 | 0.09 | |||
Ho | 0.42 | 0.48 | 0.46 | 0.44 | 0.53 | 0.64 | 0.04 | 0.02 | |||
Er | 1.03 | 1.15 | 1.13 | 1.09 | 1.23 | 1.41 | 0.12 | 0.05 | |||
Tm | 0.13 | 0.15 | 0.14 | 0.15 | |||||||
Yb | 0.90 | 0.90 | 1.00 | 0.89 | 0.98 | 1.08 | 0.09 | 0.05 | |||
Lu | 0.09 | 0.13 | 0.13 | 0.13 | 0.14 | 0.15 | 0.01 | 0.01 | |||
Cu | 44.8 | 38.1 | 39.4 | 40.7 | 45.5 | 59.4 | 1.1 | 4.4 | |||
Li | 57 | 71 | 66 | 66 | |||||||
Zn | 58 | 66 | 62.4 | 61.6 | 67.8 | 55.5 | 9.8 | 11.5 | |||
Cs | 0.49 | 0.47 | 0.43 | 0.39 | 0.55 | 0.14 | 0.04 | 0.07 | |||
Ga | 12.1 | 11.5 | 10.3 | 11.5 | 12.6 | 15.6 | 0.67 | 3.4 | |||
Ge | 1 | 1 | 1 | 1 | |||||||
Pb | 26.0 | 23.8 | 29.3 | 25.2 | 31.4 | 5.3 | 0.89 | 0.55 | |||
V | 43 | 42.7 | 41.4 | 71.7 | 46.5 | 139 | 11.3 | 12.3 | |||
K2O/Na2O | 5.95 | 6.65 | 5.87 | 5.58 | 4.28 | 1.62 | 1.00 | 1.00 | |||
(K2O+Na2O)/Al2O3 | 1.11 | 1.15 | 1.14 | 1.27 | 1.13 | 0.80 | 0.36 | 1.02 | |||
Mg# | 0.794 | 0.794 | 0.795 | 0.795 | 0.787 | 0.807 | 0.761 | 0.673 |
97-10 Core-Silver City Dome | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Lamproites | |||||||||||
Depth (feet; inches) | 38'0" | 41'10" | 50'9" | 53'8" | 58'7" | 61'1" | 65'2" | 70'2" | 72'7" | 79'11" | 83'9" |
Depth (meters) | 11.58 | 12.75 | 15.47 | 16.36 | 17.86 | 18.62 | 19.86 | 21.39 | 22.12 | 24.36 | 25.53 |
SiO2 | 45.22 | 46.53 | 46.25 | 47.29 | 46.1 | 48.95 | 43.83 | 44.59 | 44.90 | 43.87 | 44.04 |
TiO2 | 3.70 | 3.84 | 3.85 | 3.70 | 3.59 | 2.97 | 3.53 | 2.84 | 2.56 | 2.85 | 2.73 |
Al2O3 | 6.62 | 6.89 | 10.10 | 7.09 | 8.89 | 11.21 | 5.09 | 5.33 | 4.43 | 5.11 | 4.97 |
Fe2O3(total) | 7.90 | 7.74 | 6.58 | 8.08 | 6.95 | 6.31 | 8.21 | 7.76 | 7.82 | 7.81 | 7.87 |
MnO | 0.11 | 0.12 | 0.09 | 0.11 | 0.12 | 0.07 | 0.15 | 0.12 | 0.15 | 0.11 | 0.11 |
MgO | 14.32 | 14.95 | 7.12 | 14.92 | 7.86 | 6.86 | 20.81 | 22.77 | 23.55 | 24.16 | 24.69 |
CaO | 5.82 | 3.81 | 6.26 | 4.18 | 6.05 | 5.48 | 3.73 | 3.10 | 2.63 | 3.37 | 2.89 |
Na2O | 1.65 | 1.28 | 0.94 | 1.55 | 0.85 | 0.84 | 1.52 | 1.43 | 1.28 | 1.61 | 1.53 |
K2O | 7.54 | 8.45 | 10.90 | 8.08 | 9.19 | 10.55 | 6.26 | 5.49 | 5.05 | 4.24 | 4.40 |
P2O5 | 2.04 | 0.96 | 3.27 | 0.19 | 1.78 | 2.93 | 0.45 | 0.41 | 0.52 | 0.50 | 0.39 |
LOI | 3.60 | 3.20 | 2.85 | 2.81 | 3.81 | 1.74 | 4.29 | 4.63 | 5.95 | 5.06 | 5.05 |
Total | 99.06 | 99.01 | 99.35 | 99.14 | 99.07 | 99.19 | 99.04 | 99.29 | 99.57 | 99.58 | 99.38 |
Rb | 121 | 136 | 154 | 162 | <2 | 132 | 210 | 198 | 240 | 132 | 156 |
Ba | 2650 | 9200 | 6530 | 9300 | 4810 | 8440 | 8800 | 5200 | 5510 | 4470 | 4330 |
Sr | 2040 | 1820 | 3500 | 895 | 28302 | 2860 | 1620 | 2000 | 1790 | 3270 | 1900 |
Th | 14.7 | 12 | 25.6 | 6.3 | 13.8 | 10.1 | 11.6 | 10 | |||
Hf | 19 | 22 | 19 | 15 | 19 | 17 | 18 | 16 | |||
Zr | 782 | 866 | 772 | 561 | 746 | 625 | 618 | 576 | |||
Ta | 8 | 4.4 | 4.6 | 3 | 3.9 | 3.2 | 4.8 | 3.3 | |||
Co | 26.8 | 46.9 | 42 | 45.6 | 85.5 | 58.5 | 75.5 | 59.3 | |||
Sc | 15 | 16 | 15 | 16 | 14 | 12 | 11 | 12 | |||
Ni | 64 | 515 | 129 | 73 | 749 | 884 | 1185 | 932 | |||
Cr | 95 | 739 | 258 | 177 | 1260 | 1240 | 1440 | 1240 | |||
U | 2.22 | 3.41 | 2.6 | 1.68 | 3.43 | 2.26 | 2.9 | 2.34 | |||
Y | 22 | 19 | 18.2 | 23 | 28 | 16.9 | 21 | 16 | 13.8 | 14.5 | 17 |
Nb | 116 | 96 | 93 | 67 | 106 | 73 | 62 | 74 | |||
La | 444 | 202 | 297 | 178 | 186 | 158 | 154 | 140 | |||
Ce | 1080 | 392 | 688 | 346 | 359 | 310 | 275 | 269 | |||
Pr | 95.1 | 45.4 | 60.9 | 40.9 | 39.6 | 34.6 | 30.3 | 29.7 | |||
Nd | 301 | 159 | 197 | 142 | 132 | 112 | 114 | 97.6 | |||
Sm | 28.6 | 19 | 20.9 | 15.7 | 15.6 | 13.4 | 11.6 | 10.6 | |||
Eu | 6.98 | 6.17 | 5.4 | 5.06 | 5.38 | 3.90 | 3.24 | ||||
Gd | 20.6 | 14.9 | 15 | 11.8 | 12.2 | 10.1 | 8.67 | 7.85 | |||
Tb | 2.24 | 1.7 | 1.67 | 1.27 | 1.41 | 1.13 | 1.14 | 0.96 | |||
Dy | 4.5 | 5.08 | 4.1 | 3.49 | 4.06 | 3.29 | 3.25 | 3.06 | |||
Ho | 0.66 | 0.85 | 0.69 | 0.60 | 0.64 | 0.55 | 0.57 | 0.52 | |||
Er | 1.47 | 2.04 | 1.66 | 1.58 | 1.66 | 1.33 | 1.55 | 1.3 | |||
Tm | 0.17 | 0.25 | 0.22 | 0.20 | 0.20 | 0.15 | 0.18 | 0.16 | |||
Yb | 1.3 | 1.6 | 1.66 | 1.3 | 1.5 | 1.1 | 1.2 | 1.1 | |||
Lu | 0.18 | 0.22 | 0.19 | 0.18 | 0.19 | 0.16 | 0.23 | 0.15 | |||
Cu | 57 | 52 | 42 | 36 | 51 | 38 | 44 | 32 | |||
Li | 11 | 31 | 12 | 12 | 35 | 38 | 37 | 34 | |||
Zn | 71 | 79 | 60 | 45 | 64 | 58 | 71 | 65 | |||
Cs | 0.2 | 0.3 | 0.2 | 0.3 | 0.5 | 0.6 | 0.8 | 0.6 | |||
Ga | 20 | 17 | 18 | 16 | 15 | 13 | 10 | 11 | |||
Ge | 2 | 2 | 2 | 1 | 2 | 1 | 1 | 1 | |||
Pb | 36 | 56 | 68 | 11 | 53 | 34 | 48 | 44 | |||
V | 65 | 103 | 111 | 52 | 35 | 43 | 59 | 32 | |||
K2O/Na2O | 4.57 | 6.60 | 11.60 | 5.21 | 10.81 | 12.56 | 4.12 | 3.84 | 3.95 | 2.63 | 2.88 |
(K2O+Na2O)/Al2O3 | 1.64 | 1.63 | 1.32 | 1.59 | 1.28 | 1.14 | 1.82 | 1.56 | 1.71 | 1.42 | 1.46 |
Mg# | 0.666 | 0.680 | 0.543 | 0.670 | 0.554 | 0.545 | 0.736 | 0.763 | 0.768 | 0.773 | 0.775 |
97-10 Core-Silver City Dome | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Lamproites | |||||||||||
Depth (feet; inches) | 89'7" | 93'3" | 98'7" | 102'10" | 108'10" | 110'10" | |||||
Depth (meters) | 27.31 | 28.42 | 30.05 | 31.34 | 33.17 | 33.78 | |||||
SiO2 | 44.00 | 44.33 | 43.56 | 46.10 | 43.88 | 47.35 | |||||
TiO2 | 2.79 | 2.79 | 3.02 | 3.11 | 3.33 | 3.4 | |||||
Al2O3 | 5.25 | 5.28 | 5.32 | 6.00 | 5.43 | 5.38 | |||||
Fe2O3(total) | 7.98 | 7.93 | 7.92 | 7.70 | 7.82 | 7.89 | |||||
MnO | 0.12 | 0.12 | 0.12 | 0.10 | 0.12 | 0.12 | |||||
MgO | 24.01 | 23.85 | 22.61 | 19.22 | 20.02 | 19.14 | |||||
CaO | 2.84 | 3.02 | 3.25 | 3.22 | 4.39 | 4.48 | |||||
Na2O | 1.61 | 1.63 | 1.61 | 1.70 | 1.66 | 1.48 | |||||
K2O | 4.65 | 4.68 | 5.41 | 5.84 | 5.68 | 5.47 | |||||
P2O5 | 0.34 | 0.36 | 0.52 | 0.28 | 1.37 | 1.01 | |||||
LOI | 4.87 | 4.92 | 4.83 | 5.15 | 4.22 | 4.02 | |||||
Total | 99.16 | 99.65 | 99.17 | 99.40 | 99.33 | 100.44 | |||||
Rb | 168 | 168 | 173 | 122 | 104 | 103 | |||||
Ba | 4300 | 4650 | 6480 | 7150 | 7300 | 2950 | |||||
Sr | 1820 | 1880 | 2300 | 2660 | 5000 | 3110 | |||||
Th | 11.6 | 13.5 | |||||||||
Hf | 18 | 21 | |||||||||
Zr | 687 | 731 | |||||||||
Ta | 4.3 | 5.8 | |||||||||
Co | 62.6 | 60.6 | |||||||||
Sc | 12 | 14 | |||||||||
Ni | 941 | 846 | |||||||||
Cr | 1220 | 1310 | |||||||||
U | 2.72 | 2.14 | |||||||||
Y | 18 | 15 | 16.5 | 13.8 | 19 | 15 | |||||
Nb | 84 | 54 | |||||||||
La | 190 | 224 | |||||||||
Ce | 356 | 402 | |||||||||
Pr | 39.1 | 42.9 | |||||||||
Nd | 130 | 138 | |||||||||
Sm | 14.6 | 15.4 | |||||||||
Eu | 4.49 | ||||||||||
Gd | 10.8 | 11.0 | |||||||||
Tb | 1.27 | 1.30 | |||||||||
Dy | 3.43 | 3.19 | |||||||||
Ho | 0.56 | 0.54 | |||||||||
Er | 1.36 | 1.49 | |||||||||
Tm | 0.18 | 0.18 | |||||||||
Yb | 1.1 | 1.1 | |||||||||
Lu | 0.17 | 0.14 | |||||||||
Cu | 41 | 43 | |||||||||
Li | 30 | 21 | |||||||||
Zn | 69 | 68 | |||||||||
Cs | 0.6 | 0.3 | |||||||||
Ga | 14 | 14 | |||||||||
Ge | 2 | 4 | |||||||||
Pb | 46 | 43 | |||||||||
V | 36 | 62 | |||||||||
K2O/Na2O | 2.89 | 2.87 | 3.36 | 3.44 | 3.42 | 3.70 | |||||
(K2O+Na2O)/Al2O3 | 1.46 | 1.47 | 1.60 | 1.52 | 1.64 | 1.55 | |||||
Mg# | 0.768 | 0.768 | 0.758 | 0.733 | 0.738 | 0.727 |
97-11 Core-Silver City Dome | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Mudstone | Lamproites | |||||||||
Depth (feet; inches) | 74'4" | 75'3" | 80'1" | 87'8" | 88'8" | 98'5" | 98'8" | 100'10" | 106'4" | 112' |
Depth (meters) | 22.7 | 22.9 | 24.4 | 26.7 | 27.0 | 30.0 | 30.1 | 30.7 | 32.4 | 34.1 |
SiO2 | 49.94 | 46.1 | 44.96 | 45.7 | 43.22 | 43.08 | 45.0 | 43.4 | 42.8 | 43.75 |
TiO2 | 0.77 | 3.58 | 4.15 | 3.13 | 3.88 | 3.37 | 2.22 | 2.60 | 3.01 | 2.88 |
Al2O3 | 20.34 | 7.07 | 5.87 | 9.67 | 4.67 | 5.12 | 7.42 | 4.67 | 4.65 | 5.05 |
Fe2O3(total) | 3.86 | 7.92 | 8.68 | 6.75 | 8.99 | 8.12 | 6.49 | 7.84 | 7.81 | 7.78 |
MnO | 0.03 | 0.11 | 0.12 | 0.05 | 0.13 | 0.17 | 0.09 | 0.12 | 0.12 | 0.12 |
MgO | 2.74 | 15.72 | 17.78 | 9.35 | 20.54 | 21.35 | 16.64 | 22.02 | 23.05 | 23.81 |
CaO | 2.72 | 4.58 | 4.48 | 7.58 | 5.77 | 4.24 | 5.14 | 3.69 | 3.72 | 3.25 |
Na2O | 0.41 | 1.67 | 1.57 | 0.49 | 1.64 | 1.60 | 0.55 | 1.41 | 1.51 | 1.66 |
K2O | 11.67 | 7.23 | 7.08 | 10.83 | 4.91 | 5.87 | 9.82 | 5.35 | 5.25 | 4.86 |
P2O5 | 0.45 | 1.43 | 0.75 | 0.03 | 1.46 | 0.88 | 1.03 | 1.16 | 0.75 | 0.49 |
LOI | 3.5 | 3.45 | 3.28 | 5.3 | 3.57 | 4.26 | 3.40 | 6.45 | 5.32 | 4.75 |
Total | 98.53 | 99.24 | 99.08 | 99.33 | 99.31 | 99.13 | 98.37 | 99.54 | 98.79 | 99.22 |
Rb | 201 | 100 | 140 | 160 | 140 | 230 | 253 | 225 | 205 | 184 |
Ba | 15481 | 1390 | 1510 | 3060 | 1720 | 7550 | 3560 | 5120 | 5370 | 5470 |
Sr | 3120 | 1880 | 1660 | 906 | 2860 | 1920 | 1450 | 2190 | 1680 | 1800 |
Th | 13.1 | 17.1 | 15.9 | 14.3 | 12.1 | 10.5 | ||||
Hf | 22 | 58 | 22 | 19 | 19 | 16 | ||||
Zr | 878 | 2310 | 893 | 731 | 640 | 589 | ||||
Ta | 3.9 | 8.5 | 4.9 | 4.6 | 3.6 | 3.7 | ||||
Co | 63.5 | 39.3 | 53.1 | 88.2 | 68.5 | 62.9 | ||||
Sc | 15 | 20 | 15 | 14 | 12 | 12 | ||||
Ni | 514 | 98 | 703 | 762 | 971 | 948 | ||||
Cr | 1020 | 257 | 1040 | 1380 | 1185 | 1300 | ||||
U | 1.85 | 2.61 | 3.12 | 3.28 | 2.62 | 2.35 | ||||
Y | 36 | 18.9 | 20 | 2 | 22 | 21 | 18 | 12.9 | 17 | 14.6 |
Nb | 77 | 155 | 104 | 106 | 57 | 80 | ||||
La | 219 | 26.9 | 260 | 247 | 186 | 147 | ||||
Ce | 424 | 54.9 | 487 | 472 | 347 | 278 | ||||
Pr | 46.8 | 6.16 | 55.2 | 52.4 | 39.1 | 30.9 | ||||
Nd | 155 | 20.9 | 183 | 174 | 133 | 102 | ||||
Sm | 17.7 | 2.2 | 19.8 | 19.3 | 14.8 | 11.6 | ||||
Eu | 4.07 | 1.04 | 4.57 | 5.78 | 3.81 | |||||
Gd | 13.2 | 1.61 | 14.9 | 14.7 | 10.2 | 8.9 | ||||
Tb | 1.52 | 0.20 | 1.67 | 1.61 | 1.25 | 1.09 | ||||
Dy | 4.36 | 0.68 | 4.56 | 4.38 | 3.06 | 3.14 | ||||
Ho | 0.73 | 0.17 | 0.74 | 0.73 | 0.50 | 0.52 | ||||
Er | 1.64 | 0.66 | 1.81 | 1.74 | 1.37 | 1.28 | ||||
Tm | 0.21 | 0.12 | 0.24 | 0.24 | 0.16 | 0.16 | ||||
Yb | 1.3 | 1.1 | 1.5 | 1.5 | 0.90 | 1.1 | ||||
Lu | 0.19 | 0.13 | 0.19 | 0.21 | 0.18 | 0.15 | ||||
Cu | 48 | 5 | 72 | 42 | 55 | 37 | ||||
Li | 135 | 13 | 132 | 62 | 56 | 59 | ||||
Zn | 60 | 44 | 87 | 86 | 67 | 53 | ||||
Cs | 0.3 | 0.4 | 0.2 | 0.5 | 0.6 | 0.5 | ||||
Ga | 17 | 12 | 20 | 15 | 14 | 12 | ||||
Ge | 2 | 2 | 2 | 2 | 2 | 1 | ||||
Pb | 69 | 5 | 57 | 51 | 22 | 39 | ||||
V | 123 | 16 | 43 | 18 | 17 | 25 | ||||
K2O/Na2O | 28.46 | 4.33 | 4.51 | 22.10 | 2.99 | 3.67 | 17.85 | 3.79 | 3.48 | 2.93 |
(K2O+Na2O)/Al2O3 | 0.65 | 1.50 | 1.75 | 1.30 | 1.72 | 1.76 | 1.55 | 1.74 | 1.76 | 1.58 |
Mg# | 0.438 | 0.686 | 0.693 | 0.604 | 0.715 | 0.743 | 0.738 | 0.755 | 0.765 | 0.771 |
97-11 Core-Silver City Dome (continued) | ||||||||
---|---|---|---|---|---|---|---|---|
Lamproites | ||||||||
Depth (feet;inches) | 121'7" | 127'3" | 131'10" | 136'2" | 141'2" | 145'4" | 146'5" | 148'5" |
Depth(meters) | 37.1 | 38.8 | 40.2 | 41.5 | 43.0 | 44.3 | 44.6 | 45.2 |
SiO2 | 44.38 | 45.46 | 44.8 | 44.13 | 45.69 | 44.1 | 44.63 | 43.94 |
TiO2 | 2.76 | 3.15 | 3.28 | 3.41 | 2.84 | 3.01 | 3.62 | 3.35 |
Al2O3 | 5.30 | 6.04 | 5.75 | 5.02 | 6.90 | 5.85 | 6.64 | 6.58 |
Fe2O3(total) | 7.88 | 7.69 | 7.70 | 7.81 | 7.07 | 7.21 | 8.01 | 7.80 |
MnO | 0.12 | 0.12 | 0.12 | 0.12 | 0.11 | 0.11 | 0.10 | 0.14 |
MgO | 22.81 | 20.53 | 20.47 | 20.43 | 16.95 | 17.31 | 18.02 | 16.37 |
CaO | 3.18 | 3.30 | 3.44 | 4.14 | 3.06 | 5.17 | 4.08 | 6.04 |
Na2O | 1.59 | 1.56 | 1.71 | 2.02 | 1.28 | 1.61 | 1.60 | 1.42 |
K2O | 5.46 | 6.02 | 5.99 | 5.17 | 7.80 | 7.04 | 7.14 | 7.56 |
P2O5 | 0.46 | 0.33 | 0.38 | 0.80 | 1.41 | 2.45 | 1.39 | 1.12 |
LOI | 4.49 | 3.63 | 4.02 | 4.64 | 4.72 | 5.55 | 3.32 | 4.79 |
Total | 99.21 | 98.93 | 98.89 | 99.05 | 99.19 | 100.03 | 99.07 | 99.32 |
Rb | 196 | 153 | 134 | 129 | 133 | 150 | 135 | 130 |
Ba | 5060 | 7670 | 7870 | 9970 | 9720 | 2010 | 1870 | 915 |
Sr | 1820 | 2060 | 3010 | 2060 | 2350 | 3360 | 2620 | 899 |
Th | 9.6 | 11.6 | 12.8 | 20.7 | 15.5 | 10.6 | ||
Hf | 17 | 18 | 19 | 1 | 21 | 21 | ||
Zr | 652 | 711 | 720 | 150 | 871 | 788 | ||
Ta | 3.1 | 4.8 | 4.3 | 8.2 | 4.4 | 5.5 | ||
Co | 75.3 | 217 | 54.6 | 56.9 | 71.1 | 47.8 | ||
Sc | 12 | 13 | 13 | 13 | 15 | 15 | ||
Ni | 934 | 787 | 765 | 784 | 620 | 565 | ||
Cr | 1070 | 1020 | 1160 | 1160 | 1010 | 969 | ||
U | 2.35 | 2.43 | 2.78 | 2.76 | 3.01 | 2.98 | ||
Y | 16 | 16 | 18.4 | 18 | 15 | 15.7 | 18.9 | 13 |
Nb | 70 | 82 | 91 | 65 | 95 | 98 | ||
La | 184 | 201 | 204 | 256 | 247 | 162 | ||
Ce | 357 | 384 | 394 | 495 | 461 | 313 | ||
Pr | 39.3 | 42.9 | 43.5 | 52.2 | 49.6 | 33.4 | ||
Nd | 130 | 140 | 142 | 175 | 160 | 109 | ||
Sm | 14.3 | 15.2 | 15.6 | 18.2 | 16.8 | 12.1 | ||
Eu | 4.11 | 4.81 | 5.13 | 4.24 | 4.02 | 2.81 | ||
Gd | 10.9 | 11.4 | 12.2 | 12.6 | 13.7 | 9.25 | ||
Tb | 1.16 | 1.26 | 1.34 | 1.49 | 1.54 | 1.06 | ||
Dy | 3.24 | 3.46 | 3.72 | 3.64 | 3.86 | 2.67 | ||
Ho | 0.49 | 0.58 | 0.60 | 0.60 | 0.62 | 0.45 | ||
Er | 1.22 | 1.39 | 1.51 | 1.57 | 1.53 | 1.23 | ||
Tm | 0.15 | 0.16 | 0.18 | 0.18 | 0.20 | 0.19 | ||
Yb | 1.1 | 1.2 | 1.3 | 1.0 | 1.4 | 1.3 | ||
Lu | 0.14 | 0.15 | 0.17 | 0.29 | 0.19 | 0.20 | ||
Cu | 41 | 44 | 43 | 74 | 70 | 55 | ||
Li | 51 | 42 | 42 | 54 | 85 | 68 | ||
Zn | 56 | 61 | 59 | 67 | 70 | 64 | ||
Cs | 0.5 | 0.3 | 0.3 | 0.4 | 0.3 | 0.4 | ||
Ga | 12 | 13 | 13 | 15 | 17 | 15 | ||
Ge | 1 | 1 | 2 | 1 | 2 | 2 | ||
Pb | 38 | 41 | 47 | 49 | 52 | 70 | ||
V | 21 | 29 | 34 | 193 | 183 | 1140 | ||
K2O/Na2O | 3.43 | 3.86 | 3.50 | 2.56 | 6.09 | 4.37 | 4.46 | 5.32 |
(K2O+Na2O)/Al2O3 | 1.61 | 1.50 | 1.62 | 1.78 | 1.53 | 1.76 | 1.56 | 1.60 |
Mg# | 0.761 | 0.746 | 0.745 | 0.742 | 0.725 | 0.725 | 0.712 | 0.698 |
97-11 Core-Silver City Dome (continued) | 98-2 Core-Silver City Dome | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Apatite? | Limestones | Lamproites | |||||||||
Depth (feet; inches) | 148'11" | 153'3" | 155'6" | 33'8" | 43'7" | 46'1" | 51'2" | 60'9" | 64'4" | 69'4" | 79'2" |
Depth (meters) | 10.26 | 13.28 | 14.05 | 15.06 | 18.52 | 19.61 | 21.13 | 24.13 | |||
SiO2 | 4.12 | 6.71 | 12.63 | 44.95 | 43.99 | 45.23 | 44.42 | 37.03 | 44.71 | 44.3 | 42.74 |
TiO2 | 0.05 | 0.06 | 0.07 | 3.87 | 3.30 | 3.49 | 3.58 | 4.34 | 3.54 | 3.01 | 2.84 |
Al2O3 | 0.31 | 0.2 | 2.3 | 6.86 | 5.91 | 5.85 | 5.75 | 5.39 | 5.60 | 4.77 | 5.19 |
Fe2O3(total) | 1.82 | 4.13 | 5.67 | 7.78 | 7.65 | 7.92 | 7.80 | 8.44 | 8.26 | 7.95 | 7.72 |
MnO | 0.1 | 0.2 | 0.21 | 0.11 | 0.12 | 0.12 | 0.12 | 0.13 | 0.12 | 0.12 | 0.12 |
MgO | 1.52 | 3.58 | 4.8 | 13.86 | 17.98 | 19.53 | 18.74 | 13.52 | 20.59 | 22.33 | 23.07 |
CaO | 47.61 | 45.03 | 39.05 | 5.47 | 3.83 | 2.48 | 3.26 | 12.95 | 3.94 | 3.75 | 3.51 |
Na2O | 0.95 | 0.37 | 0.52 | 0.85 | 0.68 | 0.65 | 0.97 | 0.50 | 0.54 | 0.51 | 0.74 |
K2O | 0.46 | 0.22 | 1.9 | 8.51 | 7.33 | 6.53 | 6.67 | 6.17 | 5.64 | 4.68 | 4.87 |
P2O5 | 35.4 | 0.07 | 0.02 | 1.38 | 2.03 | 0.91 | 1.16 | 2.42 | 0.39 | 0.7 | 0.61 |
LOI | 3.5 | 37.75 | 32.7 | 4.65 | 4.95 | 5.39 | 5.41 | 7.69 | 4.57 | 6.48 | 5.16 |
Total | 96.27 | 98.49 | 99.99 | 99.01 | 99.02 | 99.64 | 99.23 | 99.23 | 99.00 | 99.53 | 97.45 |
Rb | <2 | <2 | 96 | 127 | 165 | 150 | 139 | 130 | 152 | 196 | 194 |
Ba | 1340 | 258 | 287 | 4240 | 8420 | 11540 | 9570 | 1720 | 7780 | 6945 | 5230 |
Sr | 2340 | 1210 | 758 | 2080 | 2620 | 2150 | 2360 | 3880 | 1970 | 2400 | 2500 |
Th | 31 | 14.1 | 13.8 | 15.4 | 10.9 | ||||||
Hf | 25 | 20 | 19 | 22 | 15 | ||||||
Zr | 964 | 814 | 767 | 593 | |||||||
Ta | 4.9 | 4.3 | 4.7 | 0.8 | 3.1 | ||||||
Co | 42.1 | 52.1 | 54.8 | 53.7 | 76.1 | ||||||
Sc | 16 | 14 | 14 | 12 | 11 | ||||||
Ni | 418 | 684 | 748 | 939 | 895 | ||||||
Cr | 897 | 1010 | 958 | 684 | 835 | 1130 | 1300 | ||||
U | 2.49 | 3.3 | 3.61 | 1.2 | 2.7 | ||||||
Y | 13 | <2 | <2 | 13 | 19 | 19.5 | 19 | 25 | 19.5 | 19 | 15.1 |
Nb | 100 | 94 | 107 | 75 | |||||||
La | 187 | 198 | 188 | 176 | 145 | ||||||
Ce | 369 | 380 | 366 | 353 | 277 | ||||||
Pr | 40.1 | 42.4 | 41.2 | 39.8 | 30.3 | ||||||
Nd | 128 | 140 | 137 | 134 | 100 | ||||||
Sm | 13.5 | 15.4 | 16.7 | 14.9 | 10.9 | ||||||
Eu | 3.89 | 5.7 | 5.47 | 4.2 | 3.56 | ||||||
Gd | 10.5 | 12.4 | 12.6 | 10.5 | 8.78 | ||||||
Tb | 1.12 | 1.39 | 1.45 | 1.33 | 1.04 | ||||||
Dy | 2.57 | 3.64 | 4.04 | 3.74 | 2.88 | ||||||
Ho | 0.41 | 0.63 | 0.66 | 0.66 | 0.5 | ||||||
Er | 1.07 | 1.52 | 1.6 | 1.73 | 1.23 | ||||||
Tm | 0.17 | 0.19 | 0.21 | 0.15 | |||||||
Yb | 1.2 | 1.3 | 1.4 | 1.3 | 1.2 | ||||||
Lu | 0.16 | 0.19 | 0.19 | 0.16 | 0.15 | ||||||
Cu | 55 | 41 | 48 | 37 | |||||||
Li | 62 | 45 | 32 | 18 | |||||||
Zn | 69 | 68 | 72 | 54 | |||||||
Cs | 0.2 | 0.4 | 0.3 | 0.8 | |||||||
Ga | 17 | 15 | 15 | 12 | |||||||
Ge | 1 | 1 | 2 | 1 | |||||||
Pb | 51 | 34 | 53 | 43 | |||||||
V | 98 | 82 | 31 | 28 | |||||||
K2O/Na2O | 10.01 | 10.78 | 10.05 | 6.88 | 12.34 | 10.44 | 9.18 | 6.58 | |||
(K2O+Na2O)/Al2O3 | 1.55 | 1.53 | 1.39 | 1.53 | 1.39 | 1.25 | 1.24 | 1.25 | |||
Mg# | 0.662 | 0.721 | 0.731 | 0.725 | 0.638 | 0.733 | 0.755 | 0.767 |
98-2 Core-Silver City Dome (continued) | Eagle 4-22-Rose Dome | |||||||
---|---|---|---|---|---|---|---|---|
Lamproites | Lamproites | Limestone | ||||||
Depth (feet; inches) | 89'4" | 100'7" | 43'10" | 45'8" | 47'4" | 47'9" | 396'4" | 408'8" |
Depth (meters) | 27.23 | 30.66 | 13.36 | 13.92 | 14.43 | 14.55 | 120.77 | 124.56 |
SiO2 | 45.5 | 43.94 | 37.85 | 38.2 | 36.97 | 38.14 | 19.77 | 2.17 |
TiO2 | 2.63 | 3.23 | 2.35 | 2.81 | 2.62 | 2.61 | 0.11 | 0.02 |
Al2O3 | 4.92 | 6.05 | 3.39 | 3.69 | 3.25 | 3.24 | 2.19 | 0.01 |
Fe2O3(total) | 7.58 | 7.65 | 7.76 | 9.32 | 10.05 | 10.15 | 0.81 | 0.39 |
MnO | 0.12 | 0.12 | 0.20 | 0.09 | 0.12 | 0.105 | 0.02 | 0.02 |
MgO | 22.32 | 18.69 | 20.58 | 23.8 | 22.31 | 22.28 | 1.08 | 0.72 |
CaO | 2.79 | 3.79 | 9.51 | 6.49 | 8.01 | 7.30 | 41.46 | 52.86 |
Na2O | 0.83 | 1.43 | 0.35 | 0.37 | 0.33 | 0.33 | 0.08 | 0.04 |
K2O | 5.24 | 6.21 | 3.48 | 2.42 | 2.56 | 2.53 | 0.5 | 0.02 |
P2O5 | 0.32 | 1.44 | 2.10 | 2.09 | 1.84 | 1.86 | 0.13 | 0.22 |
LOI | 7.33 | 4.57 | 11.11 | 9.35 | 10.5 | 9.95 | 32.95 | 42.15 |
Total | 100.25 | 97.99 | 99.21 | 99.11 | 99.20 | 99.19 | 99.24 | 98.83 |
Rb | 207 | 130 | 112.5 | 81 | 93 | 94 | <2 | <2 |
Ba | 4990 | 5430 | 2715 | 2200 | 3560 | 4030 | 66 | 20 |
Sr | 1700 | 2260 | 1975 | 1950 | 2030 | 2035 | 1110 | 1730 |
Th | 12.1 | 13.1 | 21.3 | 21.8 | ||||
Hf | 18 | 18 | 4 | 11 | ||||
Zr | 620 | 726 | 423 | 732 | <2 | 14 | ||
Ta | 0.9 | 3.7 | 8.2 | 6.2 | ||||
Co | 56.8 | 82.6 | 48.4 | 68.9 | ||||
Sc | 12 | 13 | 15.0 | 16 | ||||
Ni | 1040 | 703 | 884 | 1320 | ||||
Cr | 1195 | 955 | 1180 | 1230 | 1160 | 1130 | ||
U | 2.42 | 3.03 | 3.17 | 4.27 | ||||
Y | 16 | 13 | 19.6 | 24 | 24 | 22.3 | <2 | <2 |
Nb | 37 | 89 | 72 | 82 | <2 | <2 | ||
La | 155 | 155 | 219 | 245 | ||||
Ce | 311 | 305 | 437 | 487 | ||||
Pr | 34.6 | 33.4 | 48.7 | 53.7 | ||||
Nd | 114 | 109 | 164 | 186 | ||||
Sm | 12.5 | 11.6 | 18.9 | 21.6 | ||||
Eu | 3.5 | 3.84 | 4.48 | 5.41 | ||||
Gd | 8.86 | 9.04 | 13.2 | 15.6 | ||||
Tb | 1.09 | 1.05 | 1.62 | 1.87 | ||||
Dy | 2.87 | 2.62 | 4.38 | 5.11 | ||||
Ho | 0.5 | 0.40 | 0.71 | 0.83 | ||||
Er | 1.37 | 1.08 | 1.89 | 2.03 | ||||
Tm | 0.16 | 0.16 | 0.20 | 0.23 | ||||
Yb | 1 | 1.1 | 1.2 | 1.4 | ||||
Lu | 0.17 | 0.16 | 0.18 | 0.18 | ||||
Cu | 39 | 48 | 83 | 82 | ||||
Li | 17 | 25 | 33 | 24 | ||||
Zn | 61 | 56 | 56 | 75 | ||||
Cs | 0.6 | 0.3 | 0.5 | 0.7 | ||||
Ga | 12 | 13 | 10 | 10 | ||||
Ge | 2 | 2 | 2 | 2 | ||||
Pb | 38 | 55 | 38 | 44 | ||||
V | 41 | 146 | 40 | 8 | ||||
K2O/Na2O | 6.31 | 4.34 | 9.94 | 6.54 | 7.76 | 7.67 | ||
(K2O+Na2O)/Al2O3 | 1.43 | 1.50 | 1.28 | 0.87 | 1.02 | 1.01 | ||
Mg# | 0.764 | 0.729 | 0.745 | 0.737 | 0.709 | 0.707 |
Eagle 4-22-Rose Dome (continued) | ||||||||
---|---|---|---|---|---|---|---|---|
Lamproites | ||||||||
Depth (feet; inches) | 411'11" | 416'11" | 418'11" | 419'6" | 422" | 423'5" | 426'5" | 429'10" |
Depth (meters) | 125.55 | 127.08 | 127.69 | 127.86 | 128.63 | 129.06 | 129.97 | 131.01 |
SiO2 | 36.73 | 42.58 | 41.45 | 37.54 | 41.13 | 41.76 | 40.1 | 38.46 |
TiO2 | 7.06 | 2.42 | 3.37 | 4.14 | 2.73 | 2.29 | 2.06 | 1.62 |
Al2O3 | 5.15 | 4.32 | 5.09 | 5.14 | 4.98 | 4.38 | 3.75 | 2.61 |
Fe2O3(total) | 11.69 | 8.97 | 8.68 | 9.83 | 8.73 | 8.33 | 8.03 | 8.04 |
MnO | 0.14 | 0.16 | 0.18 | 0.135 | 0.16 | 0.15 | 0.13 | 0.14 |
MgO | 12.71 | 22.91 | 20.39 | 20.90 | 23.45 | 25.71 | 26.95 | 30.55 |
CaO | 11.63 | 5.19 | 7.62 | 7.95 | 4.54 | 3.89 | 3.78 | 3.05 |
Na2O | 1.38 | 1.39 | 1.42 | 1.40 | 1.16 | 0.74 | 0.5 | 0.19 |
K2O | 5.63 | 3.58 | 4.18 | 4.17 | 4.20 | 4.33 | 4.1 | 3.59 |
P2O5 | 3.63 | 1.23 | 1.40 | 3.03 | 1.84 | 1.58 | 1.35 | 1.35 |
LOI | 3.25 | 5.86 | 4.34 | 4.47 | 5.92 | 6.7 | 7.85 | 8.60 |
Total | 99.90 | 99.13 | 99.24 | 99.76 | 99.17 | 100.26 | 99.04 | 99.16 |
Rb | 172.5 | 149 | 148 | 137 | 198 | 223 | 211 | 177 |
Ba | 5080 | 2585 | 8080 | 6660 | 1040 | 1300 | 1560 | 6975 |
Sr | 2845 | 1960 | 1825 | 2630 | 2340 | 2180 | 2250 | 1730 |
Th | 42 | 23.1 | 29.7 | 31.1 | 16 | |||
Hf | 1 | 18 | 22 | 12 | 12 | |||
Zr | 817 | 644 | 1050 | 605 | 449 | |||
Ta | 31.6 | 1.9 | 7.6 | 2.2 | 0.5 | |||
Co | 40.7 | 61.7 | 48.8 | 63 | 73.1 | |||
Sc | 37 | 15 | 27 | 14 | 12 | |||
Ni | 128 | 1110 | 477 | 1030 | 1470 | |||
Cr | 781.5 | 1205 | 1005 | 1030 | 1585 | 1370 | 1500 | 1020 |
U | 11.7 | 5.4 | 6.53 | 4.86 | 3.58 | |||
Y | 38.1 | 25.7 | 29.6 | 37 | 22.1 | 23 | 22 | 16.8 |
Nb | 291 | 85 | 121 | 88 | 41 | |||
La | 469 | 240 | 333 | 335 | 176 | |||
Ce | 872 | 481 | 625 | 710 | 350 | |||
Pr | 96.6 | 52.6 | 68.1 | 77.3 | 39.7 | |||
Nd | 335 | 175 | 235 | 258 | 135 | |||
Sm | 41.6 | 20.1 | 27.8 | 27 | 15.1 | |||
Eu | 4.96 | 6.03 | ||||||
Gd | 29.5 | 14.8 | 20.2 | 18.3 | 10.2 | |||
Tb | 3.63 | 1.92 | 2.45 | 2.19 | 1.28 | |||
Dy | 10.4 | 5.52 | 7.05 | 5.06 | 3.51 | |||
Ho | 1.65 | 0.92 | 1.15 | 0.80 | 0.54 | |||
Er | 4.21 | 2.44 | 2.99 | 1.99 | 1.52 | |||
Tm | 0.45 | 0.31 | 0.34 | 0.22 | 0.16 | |||
Yb | 2.7 | 1.8 | 2.0 | 1.3 | 1.0 | |||
Lu | 0.42 | 0.25 | 0.32 | 0.17 | 0.15 | |||
Cu | 179 | 79 | 168 | 80 | 60 | |||
Li | 22 | 10 | 28 | 15 | 8 | |||
Zn | 121 | 73 | 53 | 69 | 69 | |||
Cs | 1.1 | 1.0 | 0.7 | 1.1 | 1.5 | |||
Ga | 17 | 16 | 9 | 15 | 7 | |||
Ge | 2 | 1 | 2 | 1 | 2 | |||
Pb | 46 | 32 | 26 | 45 | 49 | |||
V | 21 | 21 | 7 | 19 | 26 | |||
K2O/Na2O | 4.08 | 2.58 | 2.94 | 2.98 | 3.62 | 5.85 | 8.20 | 18.89 |
(K2O+Na2O)/Al2O3 | 1.62 | 1.43 | 1.35 | 1.33 | 1.30 | 1.35 | 1.40 | 1.61 |
Mg# | 0.545 | 0.737 | 0.721 | 0.700 | 0.747 | 0.772 | 0.787 | 0.807 |
Eagle 4-22-Rose Dome (continued) | |||||||||
---|---|---|---|---|---|---|---|---|---|
Lamproites | |||||||||
Depth (feet; inches) | 431'8" | 433'11" | 438'4" | 441'9" | 442'10" | 443'6" | 446' | 448'9" | 450'10" |
Depth (meters) | 131.57 | 132.26 | 133.60 | 134.65 | 134.98 | 135.18 | 135.94 | 136.78 | 137.41 |
SiO2 | 38 | 38.53 | 38.46 | 37.47 | 39.59 | 38.34 | 39.15 | 39.4 | 41.08 |
TiO2 | 1.88 | 2.02 | 2.09 | 2.12 | 1.35 | 3.61 | 2.81 | 2.02 | 1.90 |
Al2O3 | 3.06 | 2.75 | 3.06 | 3.11 | 1.73 | 3.78 | 3.24 | 2.64 | 2.81 |
Fe2O3(total) | 7.99 | 8.23 | 8.28 | 8.35 | 8.57 | 8.88 | 9.06 | 8.36 | 8.32 |
MnO | 0.13 | 0.14 | 0.14 | 0.16 | 0.14 | 0.15 | 0.14 | 0.14 | 0.14 |
MgO | 29.48 | 29.43 | 29.48 | 27.57 | 31.25 | 25.01 | 25.11 | 29.05 | 27.78 |
CaO | 3.11 | 3.41 | 3.05 | 4.22 | 2.64 | 5.19 | 4.47 | 3.1 | 2.93 |
Na2O | 0.23 | 0.28 | 0.23 | 0.24 | 0.31 | 0.79 | 0.64 | 0.36 | 0.50 |
K2O | 4.03 | 4.03 | 4.07 | 4.32 | 2.91 | 4.38 | 4.35 | 4.05 | 4.80 |
P2O5 | 1.48 | 1.59 | 1.22 | 1.35 | 0.96 | 1.77 | 1.83 | 1.11 | 0.07 |
LOI | 8.85 | 7.85 | 8.89 | 9.54 | 9.90 | 6.92 | 7.88 | 8.8 | 8.70 |
Total | 99.00 | 99.25 | 99.65 | 99.06 | 99.71 | 99.32 | 99.07 | 99.35 | 99.24 |
Rb | 186 | 180 | 196 | 205 | 136 | 167 | 202 | 176 | 199 |
Ba | 5150 | 6910 | 5150 | 3580 | 1575 | 1680 | 1720 | 1320 | 1190 |
Sr | 1550 | 1870 | 1630 | 1850 | 1590 | 2640 | 2185 | 1430 | 859 |
Th | 20.9 | 9.6 | 23.8 | 15.7 | |||||
Hf | 17 | 11 | 10 | 12 | |||||
Zr | 573 | 434 | 767 | 477 | |||||
Ta | 0.5 | 0.5 | 0.5 | 0.5 | |||||
Co | 64.7 | 77.8 | 62.7 | 69 | |||||
Sc | 13 | 11 | 17 | 12 | |||||
Ni | 1210 | 1710 | 1130 | 1320 | |||||
Cr | 1300 | 1160 | 1370 | 1440 | 538 | 1440 | 1035 | 750 | 993 |
U | 3.51 | 2.98 | 5.57 | 3.36 | |||||
Y | 20 | 21 | 21 | 17.8 | 15.6 | 30 | 25.5 | 21 | 17.8 |
Nb | 56 | 37 | 90 | 51 | |||||
La | 224 | 118 | 274 | 190 | |||||
Ce | 464 | 216 | 558 | 352 | |||||
Pr | 53.0 | 24.3 | 61.4 | 39.1 | |||||
Nd | 179 | 83 | 210 | 131 | |||||
Sm | 19.9 | 9.9 | 24.5 | 14.7 | |||||
Eu | 4.79 | 2.42 | 5.86 | 3.42 | |||||
Gd | 13.3 | 7.31 | 16.7 | 10.5 | |||||
Tb | 1.64 | 0.92 | 2.08 | 1.32 | |||||
Dy | 4.32 | 2.74 | 5.68 | 3.64 | |||||
Ho | 0.68 | 0.46 | 0.91 | 0.58 | |||||
Er | 1.69 | 1.24 | 2.42 | 1.51 | |||||
Tm | 0.19 | 0.13 | 0.25 | 0.17 | |||||
Yb | 1.2 | 0.9 | 1.5 | 1.0 | |||||
Lu | 0.17 | 0.11 | 0.22 | 0.13 | |||||
Cu | 64 | 52 | 86 | 61 | |||||
Li | 9 | 13 | 9 | 49 | |||||
Zn | 62 | 91 | 74 | 68 | |||||
Cs | 1.1 | 1.1 | 1.2 | 0.9 | |||||
Ga | 9 | 6 | 10 | 8 | |||||
Ge | 2 | 2 | 2 | 2 | |||||
Pb | 37 | 36 | 53 | 33 | |||||
V | 42 | 75 | 32 | 26 | |||||
K2O/Na2O | 17.52 | 14.39 | 17.70 | 18.00 | 9.39 | 5.54 | 6.80 | 11.25 | 9.59 |
(K2O+Na2O)/Al2O3 | 1.55 | 1.75 | 1.56 | 1.63 | 2.12 | 1.60 | 1.78 | 1.88 | 2.14 |
Mg# | 0.802 | 0.797 | 0.797 | 0.784 | 0.800 | 0.756 | 0.753 | 0.793 | 0.786 |
Eagle 4-22-Rose Dome (continued) | Eagle 5-Rose Dome | ||||||||
---|---|---|---|---|---|---|---|---|---|
Limestone | Mudstone | Lamproites | |||||||
Depth (feet; inches) | 452'2" | 452'5" | 456'5" | 460'9" | 364'6" | 383'4" | 390'2" | 398'1" | 406'3" |
Depth (meters) | 137.82 | 137.90 | 139.11 | 140.43 | 110.10 | 116.84 | 118.92 | 121.34 | 123.83 |
SiO2 | 2.94 | 1.1 | 55.46 | 55.88 | 37.0 | 41.3 | 39.83 | 37.82 | 37.95 |
TiO2 | 0.02 | 0.03 | 0.76 | 0.74 | 4.08 | 3.36 | 2.47 | 2.26 | 2.14 |
Al2O3 | 0.03 | 0.07 | 15.54 | 15.15 | 3.7 | 5.49 | 5.26 | 4.3 | 3.6 |
Fe2O3(total) | 0.17 | 0.26 | 4.93 | 5.46 | 11.16 | 8.38 | 8.18 | 8.32 | 8.56 |
MnO | 0.04 | 0.01 | 0.05 | 0.04 | 0.19 | 0.15 | 0.14 | 0.14 | 0.14 |
MgO | 1.2 | 0.58 | 2.89 | 2.63 | 17.6 | 21.83 | 25.63 | 28.28 | 29.3 |
CaO | 45.95 | 54.32 | 3.97 | 4.6 | 8.09 | 4.28 | 3.45 | 3.23 | 3.84 |
Na2O | 0.16 | 0.01 | 0.46 | 0.39 | 0.47 | 1.08 | 0.79 | 0.51 | 0.37 |
K2O | 0.01 | 0.01 | 10.17 | 7.11 | 8.12 | 6.48 | 5.88 | 4.81 | 3.79 |
P2O5 | 6.99 | 0.13 | 0.22 | 0.12 | 4.49 | 1.89 | 1.27 | 1.63 | 1.7 |
LOI | 34.3 | 42.85 | 5.5 | 7.95 | 3.38 | 4.39 | 5.79 | 7.25 | 8.25 |
Total | 92.60 | 99.57 | 100.12 | 100.15 | 99.13 | 99.28 | 99.22 | 99.03 | 100.03 |
Rb | <2 | <2 | 174 | 169 | 202 | 208 | 206 | 177 | 150 |
Ba | 2850 | 126 | 1290 | 494 | 3810 | 2920 | 2830 | 2120 | 1130 |
Sr | 4000 | 1590 | 248 | 243 | 3610 | 2760 | 2510 | 2090 | 2240 |
Th | 14.4 | 39.2 | 25.3 | 22.7 | 19 | ||||
Hf | 8 | 18 | 12 | 14 | 13 | ||||
Zr | 12 | 135 | 133 | 558 | 663 | 499 | 496 | 503 | |
Ta | 8.7 | 10.2 | 7.8 | 7.2 | 5.9 | ||||
Co | 65.7 | 59.1 | 73.6 | 78.3 | 80.1 | ||||
Sc | 18 | 17 | 12 | 13 | 13 | ||||
Ni | 501 | 641 | 974.5 | 1120 | 1215 | ||||
Cr | 1140 | 979 | 1190 | 1500 | 1330 | ||||
U | 4.96 | 4.63 | 3.86 | 2.75 | 3.52 | ||||
Y | 60 | <2 | 50 | 37 | 35.7 | 27.5 | 16.5 | 11.0 | 17.8 |
Nb | <2 | 9 | 11 | 183.5 | 134 | 91.5 | 86.5 | 86.5 | |
La | 251 | 462 | 331 | 296 | 241 | ||||
Ce | 446 | 847 | 752 | 606 | 483 | ||||
Pr | 47.9 | 99.6 | 73.6 | 67.9 | 54.7 | ||||
Nd | 163 | 342 | 248 | 228 | 187 | ||||
Sm | 21.1 | 37.9 | 25.4 | 22.1 | 20.2 | ||||
Eu | 5.97 | 8.61 | 5.70 | 4.87 | 4.65 | ||||
Gd | 16.3 | 23.9 | 15.9 | 13.5 | 13.3 | ||||
Tb | 2.04 | 2.77 | 1.83 | 1.51 | 1.56 | ||||
Dy | 7.19 | 7.38 | 4.33 | 3.07 | 4.44 | ||||
Ho | 1.225 | 1.125 | 0.655 | 0.475 | 0.68 | ||||
Er | 3.14 | 2.48 | 1.41 | 1.11 | 1.51 | ||||
Tm | 0.42 | 0.29 | 0.20 | 0.14 | 0.20 | ||||
Yb | 2.4 | 1.9 | 1.3 | 1.1 | 1.2 | ||||
Lu | 0.345 | 0.245 | 0.17 | 0.15 | 0.155 | ||||
Cu | 80 | 76 | 49 | 54 | 51 | ||||
Li | 16 | 23 | 37 | 18 | 11 | ||||
Zn | 90 | 73 | 64 | 50 | 60 | ||||
Cs | 1.0 | 1.0 | 1.5 | 1.3 | 1.3 | ||||
Ga | 14 | 17 | 13 | 11 | 10 | ||||
Ge | 2 | 2 | 1 | 2 | 1 | ||||
Pb | 25 | 49 | 37 | 40 | 36 | ||||
V | 42 | 23 | 43 | 90 | 27 | ||||
K2O/Na2O | 0.06 | 17.28 | 6.00 | 7.44 | 9.43 | 10.24 | |||
(K2O+Na2O)/Al2O3 | 9.13 | 2.58 | 1.60 | 1.46 | 1.41 | 1.31 | |||
Mg# | 0.886 | 0.634 | 0.741 | 0.775 | 0.789 | 0.790 |
Eagle 5-Rose Dome | ||||
---|---|---|---|---|
Lamproites | Limestone | |||
Depth (feet; inches) | 421'6" | 427'7" | 428'3" | 429'6" |
Depth (meters) | 128.47 | 130.33 | 130.53 | 130.91 |
SiO2 | 41.6 | 40.83 | 11.22 | 3.3 |
TiO2 | 1.85 | 2.09 | 0.18 | 0.01 |
Al2O3 | 2.95 | 2.96 | 0.95 | 0.09 |
Fe2O3(total) | 8.68 | 8.09 | 0.34 | 0.1 |
MnO | 0.15 | 0.13 | 0.03 | 0.02 |
MgO | 28.71 | 26.41 | 4.65 | 0.54 |
CaO | 2.12 | 3.39 | 44.53 | 53.66 |
Na2O | 1 | 1.13 | 1.65 | 0.04 |
K2O | 3.62 | 4.18 | 0.16 | 0.06 |
P2O5 | 0.62 | 1.87 | 30.51 | 0.1 |
LOI | 8.00 | 7.00 | 4.44 | 41.25 |
Total | 99.91 | 99.06 | 99.35 | 99.42 |
Rb | 120 | 149 | <2 | <2 |
Ba | 4900 | 6520 | 2060 | 83 |
Sr | 1150 | 2170 | 3920 | 2030 |
Th | 12.3 | 14.3 | 2.1 | 0.1 |
Hf | 12 | 13 | <1 | <1 |
Zr | 438 | 522 | 13.7 | 6.9 |
Ta | 4.4 | 4.9 | <0.5 | <0.5 |
Co | 85.5 | 79.4 | 1 | 0.8 |
Sc | 13 | 14 | <5 | <5 |
Ni | 1375 | 1160 | 15 | 16.5 |
Cr | 636 | 960 | 14 | <10 |
U | 3.32 | 3.37 | 6.35 | 1.06 |
Y | 10.6 | 13.9 | 10.4 | 1.9 |
Nb | 83 | 81.5 | 5.5 | 2 |
La | 160 | 199 | 84 | 1.4 |
Ce | 321 | 384 | 156 | 1.9 |
Pr | 35.5 | 42.6 | 16.7 | 0.3 |
Nd | 123 | 145 | 55.4 | 1 |
Sm | 13.6 | 16 | 6.3 | 0.2 |
Eu | 3.85 | 4.58 | 1.79 | 0.11 |
Gd | 8.555 | 10.6 | 4.69 | 0.23 |
Tb | 1.02 | 1.23 | 0.59 | 0.04 |
Dy | 2.64 | 3.36 | 2.06 | 0.21 |
Ho | 0.41 | 0.535 | 0.34 | <0.05 |
Er | 0.95 | 1.33 | 0.72 | 0.12 |
Tm | 0.12 | 0.16 | 0.08 | <0.05 |
Yb | 1.1 | 1.2 | 0.4 | <0.1 |
Lu | 0.145 | 0.15 | 0.06 | <0.05 |
Cu | 49 | 59 | 25 | <5 |
Li | <10 | 10 | <10 | <10 |
Zn | 44 | 54 | 18 | 6 |
Cs | 0.7 | 1.0 | <0.1 | <0.1 |
Ga | 8 | 9 | 2 | <1 |
Ge | 2 | 2 | <1 | <1 |
Pb | 34 | 33 | 12 | <5 |
V | 132 | 277 | 141 | 14 |
K2O/Na2O | 3.62 | 3.70 | 0.10 | |
(K2O+Na2O)/Al2O3 | 1.89 | 2.16 | 3.04 | |
Mg# | 0.784 | 0.782 | 0.938 |
Table 4--The means and standard deviations of lamproite samples in southeastern Kansas.
Silver City Dome | ||||||||
---|---|---|---|---|---|---|---|---|
Depth (meters) | 92-5 (14 samples) 19.9 to 31.5 |
92-11 (14 samples) 17.75 to 34.9 |
92-10 (14 samples) 8.61 to 24.9 |
97-10 (17 samples) 11.6 to 33.8 |
||||
Mean | StDev | Mean | StDev | Mean | StDev | Mean | StDev | |
SiO2 | 45.93 | 1.52 | 44.21 | 2.02 | 43.67 | 1.72 | 45.34 | 1.57 |
TiO2 | 3.20 | 0.26 | 2.86 | 0.68 | 3.01 | 0.69 | 3.21 | 0.43 |
Al2O3 | 5.73 | 0.72 | 5.18 | 1.44 | 5.28 | 1.17 | 6.38 | 1.94 |
Fe2O3(total) | 7.73 | 0.55 | 7.87 | 0.26 | 8.01 | 0.58 | 7.66 | 0.53 |
MnO | 0.12 | 0.02 | 0.12 | 0.01 | 0.12 | 0.03 | 0.12 | 0.02 |
MgO | 19.02 | 3.20 | 23.18 | 5.12 | 22.60 | 4.99 | 18.29 | 6.22 |
CaO | 4.29 | 1.58 | 3.25 | 0.72 | 3.85 | 1.28 | 4.03 | 1.20 |
Na2O | 1.83 | 0.30 | 1.25 | 0.40 | 0.76 | 0.21 | 1.42 | 0.29 |
K2O | 5.25 | 1.31 | 4.75 | 1.84 | 4.34 | 1.21 | 6.58 | 2.14 |
P2O5 | 0.75 | 0.74 | 0.64 | 0.31 | 1.64 | 0.57 | 1.02 | 0.95 |
LOI | 4.89 | 1.55 | 5.57 | 1.27 | 5.66 | 1.02 | 4.18 | 1.07 |
Total | 99.30 | 0.44 | 99.42 | 0.21 | 99.37 | 0.31 | 99.34 | 0.34 |
Rb | 125 | 25 | 149 | 36 | 120 | 26 | 155 | 38 |
Ba | 4675 | 3126 | 3578 | 1709 | 2626 | 871 | 6004 | 2108 |
Sr | 1761 | 639 | 1930 | 609 | 1987 | 332 | 3927 | 6352 |
Th | 13.7 | 5.1 | 11.0 | 2.7 | 12.6 | 3.5 | 12.9 | 5.1 |
Hf | 20.7 | 1.6 | 18.2 | 5.3 | 17.5 | 3.2 | 18.4 | 2.1 |
Zr | 855 | 102 | 738 | 201 | 669 | 228 | 696 | 100 |
Ta | 3.9 | 0.4 | 3.6 | 1.1 | 3.8 | 1.0 | 4.5 | 1.5 |
Co | 49.4 | 6.7 | 58.4 | 10.0 | 55.2 | 14.9 | 56.3 | 16.9 |
Sc | 16.7 | 10.4 | 12.8 | 2.9 | 12.9 | 2.7 | 13.7 | 1.8 |
Ni | 687 | 155 | 915 | 300 | 817 | 389 | 632 | 410 |
Cr | 1008 | 125 | 1053 | 207 | 1046 | 239 | 898 | 530 |
U | 3.0 | 0.9 | 2.2 | 0.6 | 2.6 | 0.8 | 2.6 | 0.6 |
Y | 16.8 | 3.9 | 13.7 | 3.2 | 15.2 | 3.3 | 18.0 | 3.8 |
Nb | 79.5 | 12.7 | 73.1 | 18.3 | 80.1 | 21.4 | 82.5 | 20.0 |
La | 183 | 28 | 169 | 28 | 186 | 40 | 217 | 91 |
Ce | 358 | 62 | 332 | 58 | 365 | 82 | 448 | 252 |
Pr | 40.2 | 7.2 | 36.5 | 6.3 | 40.7 | 10.0 | 45.9 | 19.4 |
Nd | 136 | 28 | 121 | 20 | 135 | 31 | 152 | 59 |
Sm | 16.2 | 4.4 | 13.4 | 2.3 | 14.8 | 3.3 | 16.5 | 5.2 |
Eu | 4.32 | 1.80 | 2.98 | 0.79 | 3.35 | 0.89 | 5.08 | 1.20 |
Gd | 10.24 | 2.56 | 8.42 | 1.53 | 9.43 | 2.02 | 12.29 | 3.73 |
Tb | 1.29 | 0.25 | 1.07 | 0.21 | 1.19 | 0.25 | 1.41 | 0.37 |
Dy | 4.03 | 0.85 | 3.23 | 0.83 | 3.61 | 0.77 | 3.75 | 0.66 |
Ho | 0.67 | 0.15 | 0.53 | 0.14 | 0.59 | 0.13 | 0.62 | 0.10 |
Er | 1.53 | 0.31 | 1.26 | 0.33 | 1.39 | 0.29 | 1.54 | 0.22 |
Tm | 0.19 | 0.04 | 0.16 | 0.03 | 0.18 | 0.05 | 0.19 | 0.03 |
Yb | 1.20 | 0.20 | 1.08 | 0.27 | 1.14 | 0.27 | 1.30 | 0.22 |
Lu | 0.17 | 0.03 | 0.14 | 0.04 | 0.15 | 0.04 | 0.18 | 0.03 |
Cu | 51.7 | 8.2 | 50.3 | 14.9 | 53.2 | 15.3 | 43.6 | 7.7 |
Li | 45.0 | 22.7 | 32.7 | 9.3 | 49.7 | 20.7 | 26.1 | 11.0 |
Zn | 74 | 9 | 72 | 9 | 71 | 11 | 65 | 9 |
Cs | 0.28 | 0.10 | 0.71 | 0.34 | 0.39 | 0.14 | 0.44 | 0.21 |
Ga | 16.0 | 1.2 | 13.8 | 3.2 | 14.2 | 2.9 | 14.8 | 3.1 |
Ge | 1.1 | 0.4 | 1.1 | 0.3 | 1.0 | 0.0 | 1.8 | 0.9 |
Pb | 37 | 11 | 29 | 13 | 32 | 13 | 44 | 15 |
V | 90 | 46 | 65 | 47 | 101 | 61 | 60 | 28 |
K2O/Na2O | 2.92 | 0.81 | 4.09 | 2.10 | 6.06 | 1.78 | 5.20 | 3.24 |
(K2O+Na2O)/Al2O3 | 1.51 | 0.15 | 1.38 | 0.13 | 1.13 | 0.11 | 1.52 | 0.17 |
Mg# | 0.73 | 0.03 | 0.76 | 0.05 | 0.75 | 0.05 | 0.70 | 0.08 |
Silver City Dome | ||||||||
---|---|---|---|---|---|---|---|---|
Depth (meters) | 97-11 (14 samples) 22.7 to 45.2 |
98-2 (10 samples) 10.3 to 30.7 |
Surface at Silver City-2 (6 samples) |
Guess-1 (12 samples) 305.4 to 312.05 |
||||
Mean | StDev | Mean | StDev | Mean | StDev | Mean | StDev | |
SiO2 | 44.42 | 0.99 | 43.68 | 2.46 | 44.03 | 3.22 | 44.33 | 3.23 |
TiO2 | 3.19 | 0.48 | 3.38 | 0.50 | 2.40 | 0.43 | 4.41 | 1.66 |
Al2O3 | 6.02 | 1.29 | 5.63 | 0.61 | 4.18 | 0.25 | 6.46 | 0.96 |
Fe2O3(total) | 7.74 | 0.61 | 7.88 | 0.28 | 7.67 | 0.45 | 8.53 | 0.80 |
MnO | 0.12 | 0.02 | 0.12 | 0.00 | 0.09 | 0.01 | 0.13 | 0.01 |
MgO | 19.01 | 3.57 | 19.06 | 3.32 | 20.95 | 2.93 | 13.00 | 3.39 |
CaO | 4.40 | 1.22 | 4.58 | 3.05 | 2.98 | 0.84 | 4.67 | 1.10 |
Na2O | 1.46 | 0.39 | 0.77 | 0.28 | 0.50 | 0.26 | 2.20 | 0.57 |
K2O | 6.67 | 1.69 | 6.19 | 1.17 | 7.19 | 1.41 | 8.99 | 0.92 |
P2O5 | 0.96 | 0.58 | 1.14 | 0.69 | ||||
LOI | 4.41 | 0.91 | 5.62 | 1.15 | 9.62 | 1.53 | 5.46 | 1.59 |
Total | 99.16 | 0.35 | 99.04 | 0.80 | 100.27 | 0.66 | 99.59 | 0.70 |
Rb | 165 | 43 | 159 | 30 | 202 | 25 | 279 | 44 |
Ba | 4696 | 3009 | 6587 | 2853 | 6595 | 2133 | 11229 | 6206 |
Sr | 2031 | 669 | 2392 | 588 | 3558 | 1012 | ||
Th | 13.7 | 3.2 | 15.8 | 6.9 | 13.5 | 2.0 | 28.2 | 15.6 |
Hf | 21.1 | 12.9 | 19.6 | 3.2 | 15.6 | 2.7 | 44.7 | 53.0 |
Zr | 828 | 507 | 747 | 136 | 1103 | 39 | ||
Ta | 5.0 | 1.7 | 3.2 | 1.7 | 4.4 | 0.8 | ||
Co | 74.9 | 46.6 | 59.7 | 14.3 | 61.9 | 6.4 | 46.1 | 8.3 |
Sc | 14.1 | 2.2 | 13.1 | 1.7 | 12.3 | 1.4 | 25.2 | 20.4 |
Ni | 704 | 240 | 775 | 205 | ||||
Cr | 1048 | 278 | 996 | 189 | 1585 | 551 | 751 | 302 |
U | 2.7 | 0.4 | 2.7 | 0.8 | ||||
Y | 16.3 | 4.5 | 17.8 | 3.6 | 34.0 | 8.5 | ||
Nb | 90.0 | 25.6 | 83.7 | 25.3 | 131.5 | 13.4 | ||
La | 195 | 65 | 172 | 20 | 164.7 | 26.1 | 341 | 155 |
Ce | 372 | 122 | 337 | 39 | 305.8 | 56.2 | 616.4 | 277.4 |
Pr | 41.0 | 13.3 | 37.4 | 4.6 | ||||
Nd | 135 | 44 | 123 | 15 | ||||
Sm | 14.8 | 4.7 | 13.6 | 2.1 | 13.8 | 3.0 | 24.5 | 13.8 |
Eu | 4.04 | 1.25 | 4.31 | 0.90 | 2.97 | 0.39 | 5.22 | 3.13 |
Gd | 11.13 | 3.58 | 10.38 | 1.62 | ||||
Tb | 1.27 | 0.39 | 1.21 | 0.17 | 0.88 | 0.45 | ||
Dy | 3.40 | 1.03 | 3.19 | 0.60 | ||||
Ho | 0.56 | 0.16 | 0.54 | 0.11 | ||||
Er | 1.41 | 0.30 | 1.37 | 0.26 | ||||
Tm | 0.18 | 0.04 | 0.17 | 0.02 | ||||
Yb | 1.23 | 0.19 | 1.21 | 0.13 | 0.76 | 0.04 | 1.28 | 0.46 |
Lu | 0.18 | 0.04 | 0.17 | 0.02 | 0.15 | 0.02 | 0.26 | 0.07 |
Cu | 48.8 | 18.9 | 44.7 | 6.8 | ||||
Li | 66.6 | 35.6 | 33.2 | 17.5 | ||||
Zn | 65 | 12 | 63 | 7 | ||||
Cs | 0.39 | 0.12 | 0.43 | 0.23 | ||||
Ga | 14.6 | 2.5 | 14.0 | 2.0 | ||||
Ge | 1.7 | 0.5 | 1.5 | 0.5 | ||||
Pb | 45 | 18 | 46 | 9 | ||||
V | 154 | 317 | 71 | 47 | ||||
K2O/Na2O | 5.84 | 5.44 | 8.69 | 2.51 | 15.75 | 3.62 | 4.39 | 1.41 |
(K2O+Na2O)/Al2O3 | 1.62 | 0.13 | 1.41 | 0.12 | 1.75 | 0.61 | 1.91 | 0.41 |
Mg# | 0.72 | 0.04 | 0.72 | 0.04 | 0.75 | 0.03 | 0.62 | 0.07 |
Depth (meters) | Silver City Dome | Rose Dome | ||||
---|---|---|---|---|---|---|
Ecco Ranch-1 (9 samples) 237.5 to 247.25 |
Eagle 4-22 (21 samples) 13.36 to 137.4 |
Eagle 5 (8 samples) 110.1 to 130.9 |
||||
Mean | StDev | Mean | StDev | Mean | StDev | |
SiO2 | 49.33 | 2.31 | 39.09 | 1.67 | 39.25 | 1.85 |
TiO2 | 3.09 | 0.30 | 2.66 | 1.21 | 2.55 | 0.77 |
Al2O3 | 7.78 | 1.95 | 3.58 | 0.95 | 3.98 | 0.96 |
Fe2O3(total) | 7.15 | 1.17 | 8.84 | 0.94 | 8.73 | 1.00 |
MnO | 0.10 | 0.01 | 0.14 | 0.02 | 0.15 | 0.02 |
MgO | 13.42 | 4.69 | 25.08 | 4.45 | 25.86 | 4.17 |
CaO | 5.00 | 1.24 | 5.29 | 2.51 | 4.02 | 1.76 |
Na2O | 1.83 | 0.44 | 0.63 | 0.45 | 0.71 | 0.33 |
K2O | 8.48 | 1.56 | 3.89 | 0.78 | 5.13 | 1.58 |
P2O5 | 1.65 | 0.72 | 1.90 | 1.13 | ||
LOI | 3.40 | 0.88 | 7.87 | 2.13 | 6.47 | 1.78 |
Total | 100.25 | 1.20 | 99.33 | 0.33 | 99.35 | 0.39 |
Rb | 174 | 28 | 164 | 42 | 173 | 32 |
Ba | 4484 | 5325 | 3527 | 2247 | 3165 | 1867 |
Sr | 2251 | 498 | 1969 | 449 | 2329 | 696 |
Th | 11.3 | 5.0 | 23.2 | 8.7 | 20.8 | 8.7 |
Hf | 17.7 | 4.5 | 11.8 | 5.9 | 13.0 | 2.8 |
Zr | 634 | 195 | 519 | 67 | ||
Ta | 5.5 | 9.2 | 6.9 | 2.0 | ||
Co | 46.6 | 15.6 | 61.7 | 11.4 | 74.9 | 8.6 |
Sc | 14.3 | 1.8 | 17.2 | 7.9 | 14.1 | 2.2 |
Ni | 1072 | 447 | 1018 | 300 | ||
Cr | 968 | 299 | 1153 | 262 | 1126 | 266 |
U | 5.0 | 2.5 | 3.7 | 0.7 | ||
Y | 23.5 | 6.0 | 18.8 | 8.6 | ||
Nb | 92.2 | 70.4 | 104.1 | 36.4 | ||
La | 182.8 | 44.5 | 257 | 95 | 273 | 93 |
Ce | 333.0 | 88.8 | 505 | 182 | 542 | 181 |
Pr | 55.9 | 19.8 | 59.7 | 20.4 | ||
Nd | 190 | 69 | 203 | 69 | ||
Sm | 14.6 | 4.7 | 21.9 | 8.5 | 22.2 | 7.3 |
Eu | 2.92 | 0.92 | 4.67 | 1.23 | 5.37 | 1.47 |
Gd | 15.42 | 5.98 | 14.50 | 4.57 | ||
Tb | 0.64 | 0.19 | 1.90 | 0.72 | 1.70 | 0.54 |
Dy | 5.22 | 2.09 | 4.60 | 1.78 | ||
Ho | 0.84 | 0.33 | 0.72 | 0.30 | ||
Er | 2.18 | 0.84 | 1.68 | 0.74 | ||
Tm | 0.24 | 0.09 | 0.21 | 0.10 | ||
Yb | 1.15 | 0.15 | 1.45 | 0.53 | 1.43 | 0.47 |
Lu | 0.19 | 0.03 | 0.21 | 0.09 | 0.19 | 0.07 |
Cu | 90.4 | 42.7 | 58.1 | 12.5 | ||
Li | 20.0 | 12.9 | 18.1 | 9.5 | ||
Zn | 74 | 19 | 61 | 15 | ||
Cs | 0.99 | 0.28 | 1.09 | 0.24 | ||
Ga | 10.6 | 3.7 | 11.3 | 2.9 | ||
Ge | 1.8 | 0.4 | 1.8 | 0.5 | ||
Pb | 40 | 8 | 36 | 7 | ||
V | 29 | 19 | 83 | 87 | ||
K2O/Na2O | 5.08 | 2.32 | 9.11 | 5.32 | 8.78 | 12.47 |
(K2O+Na2O)/Al2O3 | 1.78 | 0.43 | 1.50 | 0.33 | 1.72 | 9.48 |
Mg# | 0.66 | 0.07 | 0.75 | 0.06 | 0.76 | 14.59 |
Table 5--Averages of lamproites compared to other lamproites.
Woodson County, Kansas | non-orogenic lamproites | |||||||
---|---|---|---|---|---|---|---|---|
All shallow Silver City-89 samples |
Average of deeper Silver City-21 samples |
Average of all Rose Dome-29 samples |
Argylle olivine lamproites-19 samples |
|||||
Mean | StDev | Mean | StDev | Mean | StDev | Mean | StDev | |
SiO2 | 44.58 | 1.95 | 46.48 | 3.78 | 39.13 | 1.69 | 40.04 | 13.87 |
TiO2 | 3.09 | 0.55 | 3.85 | 1.41 | 2.63 | 1.09 | 3.01 | 0.48 |
Al2O3 | 5.64 | 1.37 | 7.03 | 1.57 | 3.69 | 0.95 | 4.78 | 0.81 |
Fe2O3(total) | 7.79 | 0.50 | 7.94 | 1.18 | 8.81 | 0.94 | 8.40 | 0.86 |
MnO | 0.12 | 0.02 | 0.12 | 0.02 | 0.14 | 0.02 | 0.13 | 0.06 |
MgO | 20.20 | 4.78 | 13.18 | 3.89 | 25.30 | 4.31 | 21.00 | 2.25 |
CaO | 3.98 | 1.54 | 4.81 | 1.14 | 4.94 | 2.37 | 5.00 | 1.90 |
Na2O | 1.23 | 0.51 | 2.04 | 0.54 | 0.65 | 0.41 | 0.15 | 0.05 |
K2O | 5.78 | 1.85 | 8.77 | 1.23 | 4.23 | 1.17 | 3.51 | 1.46 |
P2O5 | 1.02 | 0.73 | 1.72 | 0.84 | 1.05 | 0.24 | ||
LOI | 5.23 | 1.67 | 4.58 | 1.67 | 7.48 | 2.10 | ||
Total | 99.35 | 0.49 | 99.87 | 0.98 | 99.34 | 0.34 | 99.72 | 0.23 |
Rb | 149 | 39 | 234 | 65 | 166 | 39 | 248 | 98 |
Ba | 4779 | 2673 | 8339 | 6650 | 3427 | 2122 | 1098 | 714 |
Sr | 2380 | 2911 | 2998 | 1049 | 2068 | 540 | 835 | 332 |
Th | 13.1 | 4.2 | 20.9 | 14.7 | 22.2 | 8.5 | 18.0 | 4.8 |
Hf | 18.9 | 6.0 | 33.2 | 41.7 | 12.3 | 4.8 | 22.3 | 5.1 |
Zr | 757 | 260 | 1141 | 72 | 586 | 162 | 746 | 156 |
Ta | 4 | 1 | 6 | 7 | 12 | 2 | ||
Co | 58.9 | 22.1 | 46.3 | 11.6 | 67.3 | 12.0 | 67.9 | 13.5 |
Sc | 13.8 | 5.0 | 20.5 | 16.2 | 15.9 | 6.2 | 16.1 | 2.1 |
Ni | 764 | 305 | 501 | 272 | 1049 | 383 | 968 | 159 |
Cr | 1056 | 334 | 844 | 313 | 1146 | 258 | 1136 | 145 |
U | 2.6 | 0.7 | 4.5 | 2.0 | 2.2 | 0.3 | ||
Y | 16.3 | 3.9 | 32.3 | 6.7 | 22.2 | 7.0 | 18.0 | 2.5 |
Nb | 80.8 | 20.3 | 115.0 | 30.1 | 97.2 | 57.5 | 200.1 | 27.3 |
La | 185 | 50 | 273 | 143 | 264 | 92 | 122 | 20 |
Ce | 363 | 117 | 495 | 257 | 520 | 178 | 256 | 43 |
Pr | 40.2 | 11.0 | 57.5 | 19.6 | ||||
Nd | 133.9 | 35.7 | 195.7 | 67.3 | 91.9 | 14.9 | ||
Sm | 14.9 | 3.9 | 20.2 | 11.8 | 22.0 | 7.8 | 13.3 | 2.4 |
Eu | 3.7 | 1.3 | 4.2 | 2.7 | 5.0 | 1.4 | 3.1 | 0.6 |
Gd | 10.18 | 2.82 | 15.03 | 5.31 | 7.52 | 1.44 | ||
Tb | 1.23 | 0.30 | 0.77 | 0.38 | 1.82 | 0.64 | 1.03 | 0.18 |
Dy | 3.56 | 0.85 | 4.96 | 1.94 | ||||
Ho | 0.59 | 0.14 | 0.79 | 0.32 | 0.78 | 0.15 | ||
Er | 1.42 | 0.30 | 1.97 | 0.82 | ||||
Tm | 0.18 | 0.04 | 0.23 | 0.09 | ||||
Yb | 1.15 | 0.25 | 1.22 | 0.36 | 1.44 | 0.49 | 1.26 | 0.17 |
Lu | 0.16 | 0.04 | 0.23 | 0.07 | 0.20 | 0.08 | 0.15 | 0.02 |
Cu | 49 | 14 | 77 | 37 | 37 | 15 | ||
Li | 44 | 26 | 19 | 11 | ||||
Zn | 69 | 10 | 68 | 18 | 102 | 47 | ||
Cs | 0.44 | 0.24 | 1.03 | 0.26 | 9.80 | 5.67 | ||
Ga | 14.6 | 2.6 | 10.9 | 3.3 | 7.9 | 2.3 | ||
Ge | 1.41 | 0.60 | 1.79 | 0.42 | ||||
Pb | 38 | 15 | 38 | 8 | 81 | 132 | ||
V | 92 | 137 | 51 | 62 | 85 | 26 | ||
K2O/Na2O | 6.00 | 4.33 | 4.69 | 1.84 | 9.02 | 5.06 | 24.41 | 12.11 |
(K2O+Na2O)/Al2O3 | 1.46 | 0.26 | 1.85 | 0.41 | 1.56 | 0.37 | 0.85 | 0.32 |
Mg# | 0.73 | 0.05 | 0.63 | 0.07 | 0.75 | 0.06 | 0.73 | 0.03 |
non-orogenic lamproites | orogenic lamproites | |||||||
---|---|---|---|---|---|---|---|---|
West Kimberley olivine lamproites-26 samples |
Cuddapah lamproites-37 samples |
El Tale lamproites, Spain-43 samples |
Spanish lamproites-5 15 samples |
|||||
Mean | StDev | Mean | StDev | Mean | StDev | Mean | StDev | |
SiO2 | 44.58 | 1.11 | 45.87 | 2.24 | 59.37 | 0.46 | 54.13 | 4.78 |
TiO2 | 3.09 | 1.20 | 3.64 | 0.79 | 1.46 | 0.00 | 1.44 | 0.12 |
Al2O3 | 5.64 | 0.56 | 5.45 | 1.80 | 12.46 | 0.09 | 10.15 | 1.63 |
Fe2O3(total) | 7.79 | 0.66 | 10.13 | 1.90 | 4.97 | 0.20 | 5.79 | 0.96 |
MnO | 0.12 | 0.01 | 0.12 | 0.05 | 0.04 | 0.01 | 0.08 | 0.03 |
MgO | 20.20 | 2.94 | 14.11 | 0.51 | 5.67 | 0.28 | 9.95 | 4.15 |
CaO | 3.98 | 0.65 | 8.18 | 1.59 | 2.58 | 0.14 | 5.07 | 2.80 |
Na2O | 1.23 | 0.10 | 0.20 | 0.22 | 1.51 | 0.18 | 1.61 | 0.84 |
K2O | 5.78 | 0.55 | 2.90 | 1.37 | 8.53 | 0.18 | 6.34 | 2.55 |
P2O5 | 1.02 | 0.35 | 1.06 | 0.33 | 1.20 | 0.02 | 0.79 | 0.29 |
LOI | 5.23 | 7.45 | 4.02 | 1.70 | 0.21 | |||
Total | 99.35 | 0.91 | 99.11 | 0.50 | 99.47 | 0.05 | 100.40 | 0.61 |
Rb | 149 | 119 | 135 | 124 | 838 | 12 | ||
Ba | 4779 | 4815 | 1095 | 447 | 1589 | 3 | 2058 | 702 |
Sr | 2380 | 111 | 749 | 157 | 521 | 67 | 896 | 547 |
Th | 13.1 | 12.8 | 16.4 | 5.2 | 113.0 | 1.0 | ||
Hf | 18.9 | 12.8 | 1.7 | 20.0 | 0.8 | |||
Zr | 757 | 237 | 482 | 77 | 765 | 20 | 571 | 358 |
Ta | 4 | 7.3 | 1.8 | 2 | 1 | |||
Co | 58.9 | 10.1 | 25.7 | 0.6 | 31.2 | 6.0 | ||
Sc | 13.8 | 5 | 20.3 | 1.4 | 17.1 | 0.9 | 18.1 | 3.4 |
Ni | 764 | 291 | 599 | 188 | 167 | 5 | ||
Cr | 1056 | 412 | 786 | 192 | 629 | 45 | 758 | 156 |
U | 2.6 | 2.8 | 3.8 | 1.1 | 17.8 | 2.7 | ||
Y | 16.3 | 3.9 | 24.7 | 5.7 | 20.0 | 1.0 | ||
Nb | 80.8 | 60.9 | 138.4 | 41.5 | 37.3 | 0.6 | 32.9 | 10.1 |
La | 185 | 97 | 186 | 67 | 72 | 1 | ||
Ce | 363 | 168 | 368 | 128 | 212 | 15 | ||
Pr | 40.2 | 41.6 | 14.7 | |||||
Nd | 133.9 | 147.7 | 50.9 | 128.5 | 17.7 | |||
Sm | 14.9 | 20.61 | 5.90 | 26.0 | 0.5 | |||
Eu | 3.7 | 5.37 | 1.43 | 4.3 | 0.5 | |||
Gd | 10.18 | 18.93 | 5.26 | 14.20 | 0.28 | |||
Tb | 1.23 | 1.59 | 0.31 | 1.85 | 0.05 | |||
Dy | 3.56 | 6.63 | 1.00 | |||||
Ho | 0.59 | 1.03 | 0.14 | |||||
Er | 1.42 | 2.46 | 0.45 | |||||
Tm | 0.18 | 0.29 | 0.03 | 0.42 | 0.01 | |||
Yb | 1.15 | 1.74 | 0.22 | |||||
Lu | 0.16 | 0.21 | 0.03 | 2.19 | 0.06 | |||
Cu | 49 | 17 | 59 | 13 | 37 | 1 | 42 | 9 |
Li | 44 | 2 | 52 | 14 | ||||
Zn | 69 | 10 | 143 | 91 | 74 | 15 | 83 | 11 |
Cs | 0.44 | 12.97 | 18.35 | 13.00 | 2.26 | |||
Ga | 14.6 | 1.3 | 23.7 | 0.6 | ||||
Ge | 1.41 | |||||||
Pb | 38 | 13 | 43 | 45 | 50 | 19 | ||
V | 92 | 47 | 122 | 34 | 114 | 4 | 104 | 13 |
K2O/Na2O | 6.00 | 1.91 | 69.75 | 69.35 | 5.73 | 0.86 | 5.59 | 4.30 |
(K2O+Na2O)/Al2O3 | 1.46 | 0.18 | 0.64 | 0.23 | 0.94 | 0.01 | 0.94 | 0.17 |
Mg# | 0.73 | 0.02 | 0.71 | 0.04 | 0.72 | 0.03 | 0.72 | 0.02 |
1--from Jaques et al., 1989 2--from Jaques et al., 1984 3--from Chalapathi Rao et al., 2004 4--from Toscani and Slvioli-Mariani, 2000 |
The Kansas lamproites, like lamproites elsewhere, are ultrapotassic (weight percent K2O/Na2O = 2.0 to 22.1), alkalic (molecular [K2O +Na2O]/Al2O3 = 1.01 to 3.04), and are enriched in mantle-incompatible elements (light REE, Ta, Hf, Ba, Rb, Sr, Th; tables 3, 4, and 5). Most samples plot in the Group I region of CaO-Al2O3 plots due to their low CaO and Al2O3 content (fig. 7). The composition of these lamproites is thus consistent with the composition of lamproites formed in continental settings as would be expected from their location. The low Al2O3 content (<11.5%) of these samples are also consistent with lamproites forming in stable continental settings (e.g., West Kimberly, Australia; Leucite Hills, Wyoming; Smoky Butte, Montana) (Altherr et al., 2004). Samples with higher and more variable Al2O3 (up to 14.8%) form in active orogenic areas (e.g., Corsica, Spain, Alps) (Altherr et al., 2004).
Figure 7--The composition of CaO in all samples is plotted against Al2O3. Most samples of the Kansas lamproites plot in the Group I field. These lamproites formed in continental settings with mild extension (Foley et al., 1987; Foley, 1994). Samples plotting in Group II are komafugites from continental rift zones. Samples plotting in Group III are ultrapotassic rocks from active orogenic regions.
The averages of the elemental concentrations from Cs (on the left) through Sm (to the right) of the Rose Dome and Silver City Dome are greater than 40 times the primitive mantle values (fig. 8). The normalized primitive mantle values of Ba and Pb are anomalously enriched relative to adjacent elements. The normalized mantle values of Ta and Nb are not as depleted relative to adjacent elements as is observed in some lamproites (Mitchell and Bergman, 1991; Altherr et al., 2004). Depletion of Ta and Nb have been related to subduction processes or to a Ti-rich mineral in the source holding back Ta and Nb (Mitchell and Bergman, 1991). Evidently such processes did not occur for these lamproites to significantly affect Ta and Nb. Negative Ti anomalies, however, are observed in these lamproites so potentially a Ti-rich mineral may have been present in the source to reduce the Ti in the melt. Ba might be anomalously enriched in the metasomatized source for these lamproites. The chondrite-normalized REE plots are enriched in the LREE relative to the HREE as is generally observed in lamproites (table 3). There are no Eu anomalies.
Figure 8--Concentration of the average values of the Silver City and Rose Dome lamproites are normalized to primitive mantle (McDonough et al., 1992).
The average values of most elements in the shallow cores at the Silver City Dome are similar to one another (table 4). The exceptions are Na2O, Li, and Cs. Samples from the deeper Guess and Ecco Ranch cores at the Silver City Dome (Cullers et al., 1996) are higher in SiO2 (not the Guess core), Al2O3 (not the Guess core), TiO2 (not the Ecco Ranch core), total Fe2O3 (not the Ecco Ranch core), K2O, Rb, Th (not the Ecco Ranch core), Hf, Zr, Y, and LREE, and lower in MgO and Mg# than the shallower cores at the Silver City Dome (table 5).
The Eagle cores at the Rose Dome are very similar in average concentrations to one another, but they contain different concentrations of many elements compared to those at the Silver City Dome (table 4). The averages of the Eagle cores are most notably lower in concentration of SiO2, TiO2, Al2O3, Na2O, K2O, Hf, and Li and higher in total Fe2O3, MgO, P2O5, Th, Co, Ni, Cr, U, Y REE, Cu, and Cs than averages of most of the shallower cores at the Silver City Dome (tables 4 and 5).
Some elements tend to vary in a similar way vertically in different shallow cores at the Silver City Dome. For example, CaO, TiO2 (except core 92-5), Al2O3, K2O, and CaO (except core 92-5) tend to be the lowest in the middle of each core and are the highest at the top and bottom of each core (e.g., see examples and exceptions in fig. 9). Also MgO, Mg#, Ni, and Co tend to be the highest toward the middle of each core, and they are the lowest at the top and bottom of each core (e.g., fig. 10). The concentrations of MgO, Mg#, Ni, and Co may be correlated to the amount of olivine and to a lesser extent to phlogopite, and the concentrations of Al2O3, K2O, and Sc may be correlated to the amount of phlogopite (Mitchell, 1985; Mitchell and Bergman, 1991; Cullers et al., 1996). The amount of TiO2 likely depends on the amount of perovskite or possibly shcherbakovite (Mitchell, 1985; Cullers et al., 1996). The TiO2 content tends to correlate with the REE and Nb content in cores 92-11, 92-10, 97-10, and 97-11, suggesting the REE and Nb content also concentrate in perovskite as observed elsewhere (Mitchell and Bergman 1991). There is little correlation between Ba and TiO2, suggesting that shcherbakovite is not a major Ba- and Ti-bearing mineral in these rocks.
Figure 9--The change of TiO2 concentration of the shallow cores of the Silver City Dome with depth.
Figure 10--The change of MgO concentration of the shallow cores of the Silver City Dome with depth.
Other elements do not have the same trend in variability with depth in different cores. For instance, the concentration of SiO2 is the lowest in the middle of cores 92-5, 92-11, and 97-10, and tends to be the highest at the top and bottom of these cores (fig. 11). The lowest SiO2 correlates to the highest amount of olivine (serpentine) and phlogopite (the most abundant minerals with the lowest SiO2 content), and the highest SiO2 content to the most diopside and K-richterite. In contrast, the amount of SiO2 tends to decrease downward in core 92-10, suggesting that the amount of the lower SiO2 minerals, olivine and phlogopite, systematically increase downward relative to the higher SiO2 minerals. Also samples within core 92-10 are highest toward the base in MgO, Mg#, Ni, and Co, also consistent with this observation. Core 98-2 has about the same SiO2 values through the core except for one low value in the middle. The SiO2 in core 97-11 changes rather erratically through the core, but it has higher SiO2 values toward the top. Again lower SiO2 values correlate to the most olivine and phlogopite and the least to the minerals with higher SiO2.
Figure 11--The change in SiO2 concentration of the shallow Silver City Dome samples with depth.
Variation in CaO might likely be correlated with diopside, richterite, or apatite variation in these rocks (Mitchell, 1985). If apatite is a major carrier of Ca, then there should be a correlation of CaO with P2O5. Indeed, CaO and P2O5 are correlated in cores 92-10, 98-2, 97-10, and 97-11 at a P2O5 of greater than about 0.8% (fig. 12), suggesting that apatite is a major carrier of these elements at higher CaO and P2O5 contents. The CaO and P2O5 are less correlated in the other cores. Samples with a poor correlation of CaO and P2O5 likely have more CaO incorporated in richterite or diopside. The Na2O content changes differently with depth in different cores. The Na2O is most likely concentrated in perovskite, shcherbakovite, or K-richterite (Mitchell, 1985; Cullers et al., 1996). The poor correlation of TiO2 and Na2O suggest that perovskite and shcherbakovite do not control most of the Na2O. Instead, this suggests that K-richterite is a major control.
Figure 12--The correlation of CaO and P2O5 in the shallow Silver City Dome (92-5, 92-11, etc.) and the Rose Dome (Eagle cores).
The loss on ignition (LOI) increases upward in cores 92-5, 92-11, 92-10, and 97-10. This suggests that the volatiles or hydrous minerals may have migrated upward to the top of these cores forming more minerals like serpentine, phlogopite, or richterite. The lack of any clear-cut trend in LOI with depth in cores 98-2 and 97-11 suggests that volatile migration may have not been so important.
The concentration of Ba decreases upward in cores 92-5, 92-10, 97-11, and the previous near-surface samples (Cullers et al., 1985). In the original study of one shallow core at the Silver City Dome, the concentration of Ba was also quite high in the overlying metamorphosed shales compared to the unmetamorphosed shales (Cullers et al., 1985). Thus, some of the Ba was believed to have moved out of the sill into the overlying bedrock. This could explain the decreased Ba upward within the sills if it is assumed that the decreased Ba flowed in H2O-rich fluids upward into the overlying bedrock. Bedrock was sampled in this study above the sills in four of the cores. The amount of Ba was not higher in the overlying limestones next to the lamproite compared to those further away in core 92-5, but Ba was higher in cores 92-10 and 92-11 (table 4). The amount of Ba was incredibly high in a hornfels (greater than 15,000 ppm) above lamproite in core 97-11. Perhaps limestones provide a greater barrier to fluid migration and Ba transport than the shales. This conclusion is consistent with the cores 92-5, 92-10, and 97-11, and the previous near-surface samples all containing shale above them in which the Ba was reduced upward into the lamproite. None of the cores with limestone above them contained reduced Ba upward in the sill.
There is a good correlation of the Th and REE concentrations, and to a lesser extent, Th and the REE with Nb and U, suggesting that these elements are concentrated in the same minerals. These elements have been known to concentrate in perovskite (Mitchell and Bergman, 1991). In addition, Th may concentrate in priderite and apatite, REE in the Ca silicates, Nb in priderite, and U in apatite (Mitchell and Bergman, 1991). Moderate correlations of Th, La, Nb, and U with TiO2 (enriched in perovskite and priderite) and P2O5 (enriched in apatite) are consistent with this possibility.
Finally Zr and Hf are well correlated with one another, suggesting that the same mineral controls them. These elements concentrate in the Zr-rich mineral, wadeite, and to a lesser extent, priderite, perovskite, and other Ti silicate minerals (Mitchell and Bergman, 1991).
The elemental changes of the two deeper Eagle cores at Rose Dome do not vary with depth like those of the shallow cores at the Silver City Dome. For instance, TiO2, Al2O3, CaO, K2O (not Eagle 4-22), P2O5, Rb (not Eagle 4-22), Sr, Zr, Y, Nb, REE, Ta, Sc, U, Cu, Zn (not Eagle 4-22), and Ga tend to decrease with increasing depth (see examples, fig. 14). The MgO, Mg#, Co, and Ni concentrations increase with increasing depth (see examples, fig. 14). This suggests that less phlogopite (correlates to K, Rb, Al, Sc, Zn, Cu), perovskite (correlates to Ti, Sr, Nb, REE, Y, Th, U), apatite (correlates to Ca, P, U), ilmenite (correlates to Ti), and wadeite (correlates to Zr and Hf), and more olivine (correlates to Mg, Mg#, Ni, Co) occurs in deeper portions than in shallower portions of these sills.
Figure 13--The change of TiO2 concentration of the shallow cores of the deeper Eagle cores of the Rose Dome with depth.
Figure 14--The change of MgO concentration of the deeper Eagle cores of the Rose Dome with depth.
Also the concentration of SiO2, Na2O, and Ba (more variable in Eagle 4-22) tend to decrease to a minimum in the middle of the deeper Rose Dome cores, and they tend to be higher at the top and bottom of the cores. Again this suggests that the highest sum of olivine and phlogopite occur in the middle of these cores with lesser sums of these minerals occurring at the top and bottom. The highest Na2O again may be due to a concentration of perovskite, shcherbakovite, or K-richterite. The fairly good correlation of TiO2 and Na2O in Eagle 4-22 suggest that perovskite and shcherbakovite may be important controls on these element oxides. The poor correlation of TiO2 with Na2O in Eagle 5 suggests that only K-richterite may be the main control. Also P2O5 correlates with CaO (fig. 12) as at Rose Dome, again suggesting that apatite is a major control for these elements.
There are systematic trends of some element concentrations vs. Mg# (examples in figs. 15 and 16). The concentration of some elements clearly increase with decreasing Mg# (fig. 15; SiO2 [in most cores], TiO2, Al2O3, and K2O with correlation coefficients ranging from 0.7 to 0.75). Note, however, that the SiO2 content of many samples from the Eagle 4 core decrease with decreasing Mg# (fig. 15). Some elements tend to more poorly increase with decreasing Mg# (fig. 15; CaO, P2O5, Sc, Ta, Zr, Hf, Th, and REE with correlation coefficients ranging from 0.28 to 0.65). A few elements tend to decrease with decreasing Mg# (fig. 16; MgO, Ni, LOI, Co, Cr). Other elements have little or no correlation with Mg#.
Figure 15--The change of SiO2, Al2O3, K2O, and P2O5 with Mg# of the deeper Eagle cores of the Rose Dome and the shallow Silver City Dome.
Figure 16--The change of LOI, Ni, Co, and Cr with Mg# of the deeper Eagle cores of the Rose Dome and the shallow Silver City Dome.
The inverse correlation of SiO2, TiO2, Al2O3, and K2O with Mg# should be due to gradual removal of ferromagnesian minerals (olivine and phlogopite with lesser diopside and richterite,) and possibly removal of perovskite and shcherbakovite. The direct correlation of MgO, Ni, Co, and Cr with Mg# should also be due to the removal of ferromagnesian minerals (especially olivine).
Metasomatized mantle near the lower portion of the Precambrian mantle lithosphere has been hypothesized to melt to form lamproites (Foley, 1992; Foley, 1993; Mitchell, 1995; Sato, 1997; Mitchell and Edgar, 2002). The exact depth of melting is uncertain. Olivine lamproites containing diamonds, however, ought to form at depths in excess of 130 to 150 km (Mitchell and Bergman, 1991; Foley, 1993; Edgar and Mitchell, 1997; Sato, 1997). Also the low Al2O3 content and high LREE/HREE ratios of olivine lamproites require garnet to remain in the source as the magma forms (Sato, 1997). The sources are likely to be metasomatized lherzolites to harzbergites that have been enriched in varied amounts of veins containing clinopyroxene, K-Ti amphibole, phlogopite, apatite, and K-Ba-Zr-Nb titanates (Jaques et al., 1986; Bergman, 1987; Mitchell and Bergman, 1991; Foley, 1993). The likely wide variation in the amount of veins versus the lherzolite-harzburgite melting can explain the wide variation in the composition of lamproites (Mitchell, 1995) even in a small area such as those at the Silver City and Rose domes (tables 11 and 12). The lower SiO2 and Al2O3 and higher MgO lamproites at Rose Dome likely result from the higher-temperature melting of a higher proportion of lherzolite-harzburgite and less vein material compared to the more SiO2-rich and MgO-poor lamproites at the Silver City Dome (Foley, 1993; Edgar and Mitchell, 1997; Sato, 1997).
The trace-element contents of the lamproites cannot be quantitatively modeled due to the wide variation in the amount of vein material relative to the harzburgite-lherzolite, to the lack of knowing the concentration of trace elements in the source, and to the lack of appropriate distribution coefficients for lamproite melts relative to minerals. A few comments can tentatively be made about the source of the lamproites from the trace-element data. The high average concentrations of Rb, Ba, Th, U, K, Ta, Nb, and the LREE (fig. 3) suggest that abundant vein material enriched in these elements melted to produce these lamproites (Mitchell and Bergman, 1991). The deeper lamproites at the Silver City Dome tend to have higher average amounts of Rb, Ba, Th, U, K, Ta, Nb, and the LREE than those at the Rose Dome (fig. 8). This suggests that a higher ratio of the vein material to lherzolite-harzburgite melted to form the lamproites at the Silver City Dome than those at Rose Dome consistent with the conclusion based on the SiO2 and MgO contents above. This is not a clear-cut difference as some of the shallower lamproites at the Silver City Dome are lower in some elements (Th, U, Ta, Nb, La) than the lamproites at Rose Dome. There may also be a significant difference in the abundance of these trace elements in the source veins that could explain this difference.
Also these samples contain minimal negative Ta and Nb anomalies in mantle-normalized plots (fig. 8). Negative Ta and Nb anomalies are contained in rocks formed by subduction so lamproites with such negative anomalies have been suggested to have source rocks formed by subduction processes (Gibson et al., 1993; Nelson and Davidson, 1993; Wannamaker et al., 2000). Thus, rocks formed by subduction were not likely a significant source during melting to form the southeastern Kansas lamproites. Finally the lack of negative Eu anomalies in the lamproites in chondrite-normalized plots suggests that no feldspar was present in the source during melting or that any significant amount of feldspar crystallized from the melts during fractional crystallization.
The deeper cores at the Silver City Dome were modeled using a settling-floating model of minerals to produce the chemical variation (Cullers et al., 1996). The Ecco Ranch sill was zoned into zones of lower MgO, Fe2O3, Co, and Cr concentrations and higher K2O and Al2O3 concentrations. This variation was attributed to decreased ferromagnesian (20% richterite, 27% phlogopite, and 5% diopside removed) and increased sanidine (5.9% added) relative to the estimated average-melt composition.
The Guess sill has less mineralogical-chemical variation than the Ecco Ranch sill except for several small zones that were drastically enriched or depleted in some elements. Mineral accumulation-depletion models did not work so well to explain such variations. Likely H2O-rich fluids, for, example, may have concentrated Ba, Th, Hf, or Sc in some of the last portions of the magma to cause enrichment of these elements locally in minerals like perovskite, shcherbakovite, and wadeite. There was no evidence of volatile loss to the surrounding sedimentary rocks in the deeper cores.
The thick, shallow sill at the Silver City Dome contains significant mineralogical and chemical variations (Cullers et al., 1985). A flow-differentiation model in which coarser crystals of olivine, diopside, richterite, and phlogopite were concentrated into the interior of the sill explained the elemental variation in this sill. The only elemental variation that could not be explained by this model was Ba, and to a lesser extent, K2O and Rb. The amount of Ba, and to a lesser extent, K2O and Rb, were high in the overlying hornfels compared to the unaltered shales. Also Ba concentrations decreased significantly upward in the sill. Thus, Ba and some K2O and Rb likely moved upward through the sill into the overlying hornfels.
The six shallow sills at the Silver City Dome in this study have many similar fractionation trends as the previously described shallow sill above. For instance, the high MgO, Mg#, Co, and Ni, and the low SiO2 in the middle compared to the top and bottom of most cores support the flow-differentiation model in which coarser phenocrysts of the ferromagnesian minerals (olivine, richterite, diopside, and phlogopite) concentrate toward the center of the sills.
Differentiation in the deeper sills at Rose Dome is quite different than the shallow sills at the Silver City Dome as many ferromagnesian minerals (olivine, richterite?, diopside?) occur toward the bottom of the sills relative to phlogopite, perovskite, apatite, ilmenite, and wadeite. Also coarser crystals do not appear to concentrate in the center of these sills. Thus, gravity settling and not flow differentiation may again be dominant control on the variation in the deeper sills at Rose Dome.
Altherr, R., Meyer, H. P., Holl, A., Volker, F., Alibert, C., McCulloch, M. T., and Majer, V., 2004, Geochemical and Sr-Nd-Pb isotopic characteristics of Late Cenozoic leucite lamproites from the East European Alpine belt (Macedonia and Yugoslavia): Contributions to Mineralogy and Petrology, v. 147, p. 58-73.
Berendsen, P., 2011, Structural setting and stratigraphy of lamproite occurrences in Woodson and Wilson counties, southeast Kansas, USA: Kansas Geological Survey, Open-file Report 2011-5, 74 p. [available online]
Bergman, S. C., 1987, Lamproites and other potassium-rich igneous rocks--a review of their occurrence, mineralogy, and geochemistry; in, Alkaline Igneous Rocks, J. G. Fitton and B. G. J. Upton, eds: Geological Society of America, Special Publication, v. 30, p. 103-190.
Chalapathi Rao, N. V., Gibson, S. A., Pyle, D. M., and Dickin, A. P., 2004, Petrogenesis of Proterozoic lamproite and kimberlites from the Cuddapah Basin and Dharwar Craton, southern India: Journal of Petrology, v. 45, p. 907-948.
Coopersmith, H. and Mitchell, R., 1989, Geology and exploration of the Rose lamproite, southeast Kansas, USA; in, Kimberlites and Related Rocks--Their Mantle/Crust Setting, Diamonds and Diamond Exploration, A. L. J. J. Ross, J. Ferguson, D. H. Green, S. Y. O'Reilly, R. V. Danchin, and A. J. A. Janse, eds.: Geological Society of Australia, Special Publication, v. 14, p. 1,179-1,191.
Cullers, R. L., Dorais, M. J., Berendsen, P., and Chaudhuri, S., 1996, The mineralogy and petrology of subsurface lamproites, late Cretaceous age, southeastern Kansas, USA: Lithos, v. 38, p. 185-206.
Cullers, R. L., Ramakrishnan, S., Berendsen, P., and Griffin, T., 1985, Geochemistry and petrogenesis of lamproites, Late Cretaceous age, Woodson County, Kansas, U.S.A.: Geochimica et Cosmochimica Acta, v. 49, p. 1,383-1,402.
Edgar, A. D., and Mitchell, R. H., 1997, Ultra high pressure-temperature melting experiments on an SiO2-rich lamproite from Smoky Butte, Montana--Derivation of siliceous lamproite magmas from enriched sources deep in the continental mantle: Journal of Petrology, v. 38, p. 457-477.
Foley, S. F., 1992, Vein-plus-wall-rock melting mechanisms in the lithosphere and the origin of potassic alkaline magmas: Lithos, v. 28, p. 435-453.
Foley, S. F., 1993, An experimental study of olivine lamproites-first results from the diamond stability field: Geochimica et Cosmochimica Acta, v. 57, p. 483-489.
Foley, S. F., 1994, Geochemische und experimentelle Untersuchungen zur Genese der kalireichen Magmatite: Neus Jahrb. Mineral. Abh., v. 167, p. 1-55.
Foley, S. F., Venturelli, G., Green, D. H., and Toscani, I., 1987, The ultrapotassic rocks-characteristics, classification, and constraints for petrogenetic models: Earth Science Review, v. 24, p. 81-134.
Franks, P., Bickford, M., and Wagner, H. C., 1971, Metamorphism of Precambrian granitic xenoliths in a mica peridotite at Rose Dome, Woodson County, Kansas--Part 2, Petrologic and mineralogic studies: Geological Society of America Bulletin, v. 82, p. 2,869-2,890.
Garbe-Schonberg, C.-D., and McMurtry, G. M., 1994, In-situ micro-analysis of platinum and rare earths in ferromanganese crusts by laser ablation-ICP-MS (LAICPMS): Fresenius' Journal of Analytic Chemistry, v. 350, nos. 4-5, p. 264-271.
Gibson, S. A., Thompson, R. N., P. T. Leat, P. T., Morrison, M. A., Hendry, G. L., Dickin, A. P., and Mitchell, J. G., 1993, Ultrapotassic magmas along the flanks of the Oligocene-Miocene Rio Grande Rift, USA--Monitors of the zone of lithospheric mantle extension and thinning beneath a continental rift: Journal of Petrology, v. 34, p. 187-228.
Govindaraju, K., 1994, 1994 compilation of working values and descriptions for 383 geostandards: Geostandards Newsletter, v. 12, p. 63-118.
Jaques, A. L., Lewis, J. D., and Smith, C. B., 1986, The kimberlites and lamproites of Western Australia: Geological Survey of Western Australia, Bulletin, v. 132, 268 p.
Jaques, A. L., Lewis, J. D., Smith, C. B., Gregory, G. P., Ferguson, J., Chappell, B. W., and McCulloch, M. T., 1984, The diamond-bearing ultrapotassic (lamproitic) rocks of the West Kimberley Region, Western Australia; in, Kimberlites I--Kimberlites and Related Rocks, J. Kornprobst, ed.: Amsterdam, Elsevier, v. I, p. 225-254.
Jaques, A. L., Sun, S. S., and Chappell, B. W., 1989, Geochemistry of the Argyle lamproite pipe, Western Australia; in, Kimberlites and Related Rocks--Their Composition, Occurrence, Origin, and Emplacement, A. L. J. J. Ross, J. Ferguson, D. H. Green, S. Y. O'Reilly, R. V. Danchin, and A. J. A. Janse, eds.: Geological Society of Australia, Special Publication, v. 14, p. 170-188.
McDonough, W. F., Sun, S.-S., Ringwood, A. E., Jagoutz, E., and Hofmann, A. W., 1992, Potassium, rubidium, and cesium in the earth and moon and the evolution of the mantle of the earth: Geochimica et Cosmochimica Acta, v. 56, p. 1,001-1,012.
Mitchell, R. H., 1985, A review of the mineralogy of lamproites: Transactions of the Geological Society of South Africa, v. 88, p. 411-437.
Mitchell, R. H., 1995, Melting experiments on a sanidine phlogopite lamproite at 4-7 BPa and their bearing on the source of lamproitic magmas: Journal of Petrology, v. 36, p. 1,445-1,474.
Mitchell, R. H., and Bergman, S. C., 1991, Petrology of lamproites: New York, Plenum Press.
Mitchell, R. H., and Edgar, A. D., 2002, Melting experiments on SiO2-rich lamproites to 6.4 GPa and their bearing on the sources of lamproite magmas: Mineralogy and Petrology, v. 74, p. 115-128.
Nelson, S. T., and Davidson, J. P., 1993, Interactions between mantle-derived magmas and mafic crust, Henry Mountains, Utah: Journal of Geophysical Research, v. 98, p. 1,837-1,852.
Sato, K., 1997, Melting experiments on a synthetic olivine lamproite up to 8 GPa--Implications to its petrogenesis: Journal of Geophysical Research, v. 102, p. 14,751-14,764.
Toscani, L., and Slavioli-Mariani, E., 2000, The lamproite of El Tale (Fortuna, southeast Spain): Chem. Erde, v. 60, p. 96-110.
Wannamaker, P. E., Hulen, J. B., and others, 2000, Early Miocene lamproite from the Colorado Plateau tectonic province, southeastern Utah, USA: Journal of Volcanic and Geothermal Research, v. 96, p. 175-190.
Kansas Geological Survey
Placed on web April 21, 2011.
Comments to webadmin@kgs.ku.edu
The URL for this page is http://www.kgs.ku.edu/Publications/Bulletins/TS23/index.html