KGS Home Geology Home Reports

Kansas Geological Survey, Open-file Report 96-35
Prev page--Results


Summary and Conclusions

The stratigraphy of loess deposits which have been investigated on Fort Riley exhibits the same sequence of loess units and intercalated buried soils as is found elsewhere in the region, but adds detail unique to the reservation. Composite stratigraphy of the late-Quaternary loess deposits preserved on the reservation consists of the basal Sangamon soil of the Last Interglacial (Illinoian age; c. 120-110 ka), Gilman Canyon Formation (a pedogenically-altered, middle Wisconsinan loess; c. >40-20 ka), Peoria loess (late-Wisconsin; c. 20-10 ka), Brady soil (Pleistocene/Holocene transition; c. 11-10 ka), Bignell loess (Holocene; c. 9-? ka), and modern surface soil.

The record of climatic change during the late Quaternary has been retained in the loess deposits of the central Great Plains, and such a record is extractable using some relatively new approaches. The loess sequences at Fort Riley represent a nearly continuous time series of climatically-forced environmental change for the late Quaternary. Application of two analytical techniques, magnetics and SIRA, is providing proxy data sets that represent a time series of climatically regulated pedogenesis/weathering and botanical composition (Johnson, 1996b). This investigation, however, presents the results of an expanded study of the opal phytolith record contained within sites from various landscape setting on the reservation (cf. Johnson et al., 1994).

Study localities included two upland sites, Sumner Hill and Bala Cemetery; a valley-wall site, Pump House Canyon; and a valley-bottom site, Manhattan Airport. Sumner Hill, a bluff top site on the north side of the Kansas River valley, has the thickest loess accumulation of all sites examined (c. 13m), extending from the Sangamon soil to the surface soil, whereas Bala Cemetery site, in the extreme northwestern part of the reservation, consists of less than 3m of loess above the limestone bedrock. Pump House Canyon site has a relatively thick accumulation of loess, probably in excess (Gilman Canyon and Peoria loesses) of 5m. Sediments at the Manhattan Airport are alluvial, not eolian, and exhibit the alluvial phase of two or more of he soils found in the upland record (Brady and Sangamon and/or Gilman Canyon).

Quality of the opal phytolith record varied appreciably among the sites. Sumner Hill produced only a marginal record for the upper 3 m, i.e., the latest Pleistocene and all of the Holocene. After some abrupt and brief fluctuations in grass composition at the end of the Pleistocene, the xeric warm-season grasses expanded as the Holocene climate and its grassland biome evolved. At the Bala Cemetery site, the Holocene record appears to be absent, with the phytolith assemblages indicating the amelioration of climate at the closure of the Pleistocene, i.e., the mesic, cool-season grasses were gradually yielding their dominance to the more xeric warm-season grasses. The quality of record at this upland site is good. The Pump House Canyon site provided the poorest phytolith record of all sites investigated thus far; phytolith preservation and concentration were good only in the upper 30-40 cm. The limited data indicate a mixed grass environment for the last 2-3,000 years on this strath. The Manhattan Airport site, a high terrace consisting of late-Pleistocene to late-Holocene alluvium, provided a good phytolith record for the upper 2m and offers an interesting mix of regional and local environmental signals. The mesic cool-season grasses slowly yield to the more xeric warm-season grasses as the Pleistocene comes to an end, but the relatively high percentage of C3 grasses may be exaggerated in the record due to the microclimate of the alluvial bottom (high soil moisture and arboreal shading).

The composite of these data portrays climatic change at the end of the Pleistocene and much of the Holocene: C3 grasses, such as the bromes, fescues and bluegrasses, gave up their dominance and the C4 grasses took the advantage, particularly the more xeric chloridoid types, such as the gramas, buffalo grass, and muhly grasses. These data provided no clear indication of major, long-term events during the Holocene, in particular the Altithermal. Notable events, both long- and short-term, are very likely part of the climatic history for the region and the reservation, but the quality of the Holocene phytolith record for the upland loess deposits is limited to the marginal record obtained at Sumner Hill. As a result, possible correlation with the magnetic record is limited.

Despite the limitations of the phytolith data obtained to date, more is known about the late-Quaternary climatic history of Fort Riley, particularly as it relates to landscape evolution and to changing environments and resources of the aboriginal peoples occupying the reservation landscape since the late Pleistocene. Grassland composition and associated gathering potential and game changed, and trees came and went from the landscape. Also, the upland environment was different from the strath and from the alluvial bottoms, and rates and magnitude of change varied among the different landscape elements.

Recommendations

Based on the results of this and past studies at Fort Riley (Johnson et al., 1994; Johnson, 1996b), it is recommended that further opal phytolith analysis be conducted in order to realize the potential of the upland paleoenvironmental record and to generate a geoarchaeological model of sufficient temporal and spatial resolution to provide the basis for development and/or testing of the computer-based geoarchaeological model under development by R. Bras and colleagues at MIT. Specific recommendations include:

  1. Selection and analysis of one or more upland sites containing expanded Holocene records in order to improve on the quality of record obtained from the Holocene phytolith record of the Sumner Hill site. After potential sites are identified, a spot check analysis of phytolith isolate quality would be made to locate sites with good records. The Bala Cemetery site indicates that quality phytolith records exist in the upland late..;.Pleistocene (Peoria) loess deposits, but such a quality record needs to be found in Holocene-age (Bignell) loess.
  2. Samples should be collected and analyzed from within and adjacent to archaeological sites located on both the uplands and stream terraces. Phytolith analysis has shown itself to be an outstanding techniques for reconstructing paleoenvironments and cultural resources use from archaeologically enriched stratigraphy.

Opal phytolith analysis is a relatively new technique and the University of Kansas Palynology Laboratory is one of the few places in the world where it is being done. Application of the technique to the loess deposits of Fort Riley has, therefore, been a learning experience upon which one can build.

Since phytolith analysis was referenced in recommendations included in the review draft of the magnetic and isotope analyses on the reservation (Johnson, 1996b), those recommendations are restated:

  1. In that the latest Pleistocene and entire Holocene are of primary interest in development of a cultural resources and landscape evolution model, further emphasis should be placed on this portion of the upland stratigraphic record. The environmental transition at the late-Pleistocene/Holocene boundary needs to be better characterized, as does the detail of the Holocene (e.g., the Altithermal, soil-forming periods). Specifically, high-resolution (e.g., 2 cm contiguous) sampling should be undertaken on two or more new sites with expanded Holocene sequences and on cores from the existing sites of Sumner Hill and Pump House Canyon for the purpose of SIRA of carbon. Further, these sites should be sampled at close interval (c. 25 cm) for 14C dating; subdividing the samples in order to individually date the total humates and humic acid and humin fractions would be helpful in deciphering the chronostratigraphy (Martin and Johnson, 1995; Johnson and Valastro, 1994). Magnetic analyses (susceptibility and frequency dependence) should also be conducted at the new sites selected.
  2. The analysis of trace element content has been used in a number of applications related to the reconstruction of late-Quaternary environmental conditions (e.g., research by Muhs et al., 1990, 1995; Reheis, 1990; and Diekmeyer, 1994). Trace elements (e.g., cerium, strontium, yttrium, zirconium) contained with in the loess and intercalated soils provide a "fingerprint" of the sediment and provide information regarding paleowind direction and loess source region. Data obtainable include not only presence or absence, but also the concentration of individual trace elements. Recent research by Johnson and Muhs (unpub. data; Johnson et al., 1993b) has documented the difference in source regions for loess deposits of eastern Colorado versus those of southern Nebraska and Kansas. For Fort Riley, two levels or orders of information can probably be derived from the loess sequences. First, trace element analysis can indicate the stratigraphic level (and time, with sufficient 14C control) at which the winds shifted from the north-northwest to the south-southwest, i.e., determine whether the trace element signature is that of the Platte River sediments or of the Kansas River sediments. The second order variations in the data will document the more subtle changes within the trace element time series. These variations will indicate small order changes in wind intensity and direction at a given location, as well as define the distance-decay function along a sampled transect. The stronger the winds, the higher the concentration of the trace elements, since they are not only rare but also represent the heavy mineralogic fraction. Short-term changes in direction will also show up in the signature: Trace element analyses should be conducted on two or more of the sites referred to in the first recommendation, with sampling being conducted at close interval (c. 2cm). Previous research (Johnson et al., 1993b, Diekmeyer, 1994, Muhs and Johnson, 1996) has indicated that a suite of eleven trace elements contains the optimal amount of information for examining Pleistocene and Holocene loess of the central Great Plains. Facilities for preparation of samples for analysis exist within this investigator's laboratory, and those for analysis exist both in the Department of Geology, University of Kansas, and at the U.S. Geological Survey, Denver, Colorado (D.R. Muhs' laboratory).
  3. Extensive archaeological surveys currently being conducted on the reservation are yielding new upland prehistoric sites, one or more of which have been found to contain evidence for Clovis (latest Pleistocene/earliest Holocene) occupation. Selected archaeological sites should be analyzed to articulate the specific paleoenvironmental record. As a corollary to the first recommendation, these sites, depending on their location relative to the nonarchaeological sites, should receive high-resolution magnetic, isotope, opal phytolith and perhaps trace-element analyses.
  4. Results of D.L. Johnson's survey of the upland loess mantle (D.L. Johnson, 1996) should be used as base line data in developing a detailed map of surface materials in order to provide the precision of information needed to articulate a detailed sequence of landscape evolution on Fort Riley. A combination of shallow coring and ground-penetrating radar surveys can be employed to provide the information for input into a GIS in order to create a detailed map of surficial geology and the spatial variation in thickness of the various map units. Shallow coring can be conducted using the trailer-mounted Giddings soils probes operated by the Department of Geography, University of Kansas. Ground-penetrating radar, conducted by dragging a skid-mounted radar system behind an all-terrain vehicle, and personnel are available through both the Department of Geology, University of Kansas and the Kansas Geological Survey.

Research conducted to date by this investigator (Johnson et al., 1994; Johnson, 1996b; this report) and by D.L. Johnson (D.L. Johnson, 1992, 1994, 1996) has defined the late-Quaternary lithostratigraphy of the reservation and documented the first-order trends in the chrono-, magneto-, and biostratigraphy (SIRA, opal phytoliths). Now that the potential for reconstruction of the late-Quaternary environmental record has been realized and broadly defined, high-resolution study needs to be undertaken at selected existing and new sites in order to extract the interpretable detail.

References Cited

Aguirre, E. and Pasini, G., 1985, The Pliocene-Pleistocene boundary: Episodes, v. 8, p. 116-120.

Alden, W.C., and Leighton, M.M., 1917, The Iowan drift, a review of the evidence of the Iowan stage of glaciation: Iowa Geological Survey, v. 26, p. 49-212.

An, Z., Kukla, G., Porter, S., 1991, Magnetic susceptibility evidence of monsoon variation on the loess plateau of central China during the last 130,000 years: Quaternary Research, v. 36, p. 29-36.

An, Z., Porter, W., Zhou, Y., Lu, D.J., Donahue, M.J., Heads, M.J., and Zheng H., 1993, Episodes of strengthened summer monsoon climate of Younger Dryas age on the Loess Plateau of Central China: Quaternary Research, v. 39, p. 45-54.

Andrews, J. T., 1987, The Late Wisconsin glaciation and deglaciation of the Laurentide Ice Sheet; in, North America and adjacent oceans during the last deglaciation, W. F. Ruddiman and H. E. Wright, Jr., eds.: Geological Society of America, The Geology of North America, v. K-3, p. 13-37.

Antevs, E., 1955, Geologic-climatic dating in the West: American Antiquity, v. 20, p. 317-335.

Arbogast, A.F., 1995, Paleoenvironments and desertification on the Great Bend Sand Prairie in Kansas: Unpublished Ph.D. dissertation, University of Kansas, 385 p.

Bard, E., Arnold, M., Fairbanks, R. G., and Hamelin, B., 1993, 230Th-234U and 14C ages obtained by mass spectrometry on corals: Radiocarbon, v. 35, p. 191-199.

Barry, R.G., 1983, Climatic environment of the Great Plains, past and present; in, Man and the changing environments in the Great Plains, W.W. Caldwell, C.B. Schultz, and T.M. Stout, eds.: Nebraska Academy of Sciences Transactions, v. 11, p. 45-55.

Bartlein, P.J., Webb, III, T., and Fleri, E., 1984, Holocene climatic change in the northwestern Midwest: pollen derived estimates: Quaternary Research, v. 22, p. 361-374.

Bayne, C.K., Davis, S.N., Howe, W.B., and O'Connor, H.G., 1971, Regional Pleistocene stratigraphy: Kansas Geological Survey, Special Distribution Publication 53, p. 4-8.

Bayne, C.K., and O'Connor, H.G., 1968, Quaternary System; in, The Stratigraphic Succession in Kansas, D.E. Zeller, ed.: Kansas Geological Survey, Bulletin 189, p. 59-67. [available online]

Benedict, J.B., and Olson, B.L., 1978, The Mount Albion Complex: a study of prehistoric man and the Altithermal: Research Report of the Center for Mountain Archaeology, v. 1, 213 p.

Bettis, E.A., III (ed.), 1990, Holocene Alluvial Stratigraphy and Selected Aspects of the Quaternary History of Western Iowa, Midwestern Friends of the Pleistocene: University of Iowa Quaternary Studies Group Contribution No. 36, 197 p.

Bozarth, S.R., 1984a, Phytolith analysis (Appendix IV); in, The Coody Creek Site, a Late Caddo Village in Eastern Oklahoma, P.M. Brockington, Jr., ed.: U.S. Army Corps of Engineers, p. 114-115

Bozarth, S.R., 1984b, Cultigen phytolith analysis at 23DX3: Unpublished report, Department of Anthropology, Wichita State University and Nebraska State Historical Society.

Bozarth, S.R., 1984c, Pollen and opal phytolith analysis, the Jetmore Mammoth Site, 14H01; in, Kansas Preservation Plan for the Conservation of Archaeological Resources, K.L. Brown and A.H. Simmons, eds.: Unpublished report, Office of Archaeological Research, Museum of Anthropology, University of Kansas, p. 4-56 to 4-67.

Bozarth, S.R., 1985, Distinctive Phytoliths from Various Dicot Species: Phytolitharien Newsletter, v. 3(3), p.7-8.

Bozarth, S.R., 1986, Phytoliths; in, Along the Pawnee Trail, Cultural Resources at Wilson Lake, D. Blakeslee and H. Garcia, eds.: U.S. Army Corps of Engineers, p. 86-101.

Bozarth, S.R., 1987a, Diagnostic Opal Phytoliths from Rinds of Selected Cucurbita Species: American Antiquity, v. 52, p. 607-615.

Bozarth, S.R., 1987b, Opal phytolith analysis of daub samples from Hatcher site; in, Archaeological Investigations of the Clinton Reservoir Area in Northeastern Kansas--National Register Evaluation of 27 Prehistoric Sites, B. Logan, ed.: U.S. Army Corps of Engineers, p. 237-244.

Bozarth, S.R., 1987c, Opal Phytolith Analysis of Edible Fruits and Nuts Native to the Central Plains: Phytolitharien Newsletter, v.4(3), p. 9-10.

Bozarth, S.R., 1987d, Phytolith analysis for cultigen identification: sites 25HN36, 25HN37, and 25HN40; in, Prehistory and Historic Cultural Resources of Selected Sites at Harlan County Lake, Harlan County, Nebraska, M. Adair and K.L. Brown, eds.: U.S. Army Corps of Engineers, p. 469-471.

Bozarth, S.R., 1988, Preliminary Opal Phytolith Analysis of Modern Analogs from Parklands, Mixed Forest, and Selected Conifer Stands in Prince Albert National Park, Saskatchewan: Current Research in the Pleistocene, v. 5, p. 45-46.

Bozarth, S.R., 1989, Opal phytoliths; in, Final Summary Report, 1986, Archaeological Investigations at 14MN328, a Great Bend Aspect Site along U.S. Highway 56, Marion County, Kansas, W.B. Lees, J.D. Reynolds, T.J. Martin, M. Adair, and S.R. Bozarth, eds.: Kansas State Historical Society, p. 85-90.

Bozarth, S.R., 1990a, Opal phytolith analysis for cultigen identification: the Quixote and Reichart sites; in, Archaeological Investigations in the Perry Lake Area, Northeastern Kansas--National Register Evaluation of 17 Sites, B. Logan, ed.: U.S. Army Corps of Engineers, p. 239-242.

Bozarth, S.R., 1990b, Results of preliminary biosilicate analysis of 14LT351 (Appendix II); in, the Archaeology of the Stigenwalt Site, R. Thies, ed.: Kansas State Historical Society Contract Archaeological Series 7, p. 146-156.

Bozarth, S.R., 1990c, diagnostic opal phytoliths from pods and selected varieties of common beans (Phaseolus vulgaris): American Antiquity, v. 55, p. 98-104.

Bozarth, S.R., 1991a, Extracting Pollen and Phytoliths from Archaeological Sediment: The Roosevelt Rural Sites Study--Laboratory Manual: Statistical Research, Tucson, AZ, submitted to U.S. Department of Interior, Bureau of Reclamation, Arizona Projects Office, p. VII-6- VII-7.

Bozarth, S.R., 1991b, Paleoenvironmental Reconstruction of the La Sena Site (25FT177) Based on Opal Phytolith Analysis: Unpublished report, Nebraska State Historical Society, 17 p.

Bozarth, S.R., 1992a, Classification of Opal Phytoliths Formed in Selected Dicotyledons Native to the Great Plains; in, Phytolith Systematics--Emerging Issues, G. Rapp, Jr. and S. Mulholland, eds.: Plenum Press, p.193-214.

Bozarth, S.R., 1992b, Paleoenvironmental Reconstruction of the Sargent Site--a Fossil Biosilicate Analysis: Unpublished report, Department of Geology, University of Kansas, 22 p.

Bozarth, S.R., 1993a, Maize (Zea mays) cob phytoliths from a central Kansas Great Bend Aspect archaeological site: Plains Anthropologist, v. 38, p. 279-286.

Bozarth, S.R., 1993b, Phytolith analysis of bison teeth calculus and impacta from sites in Kansas and Oklahoma; in, Investigation of Seasonality, Herd Structure, Taphonomy, and Paleoecology at Folsom bison kill sites on the Great Plains: 10,500 B.P., J. Hofman, ed.: Unpublished manuscript, Department of Anthropology, University of Kansas, 8 p.

Bozarth, S.R., 1993c, Biosilicate Assemblages of Boreal Forests and Aspen Parklands; in, Current Research in Phytolith Analysis: Applications in Archaeology and Paleoecology, D. Pearsall and D.P. Piperno, eds.: Museum of Applied Science Center for Archaeology Series, v. 10, University of Pennsylvania, p. 202-207.

Bozarth, S.R., 1995, Analysis of fossil biosilicates from the valley fill; in, Stratigraphy and Paleoenvironments of Late Quaternary Valley Fills on the Southern High Plains, V.T. Holliday, ed.: Geological Society of America, Memoir 186, p. 161-171.

Bradbury, J.P., 1980, Late Quaternary vegetation history of the central Great Plains and its relationship to eolian processes in the Nebraska Sand Hill: U.S. Geological Survey, Professional Paper 1120-C, 8 p. [available online]

Broecker, W. S., Andre, M., Wolfli, W., Oeschger, H., Bonani, G., Kennett, J., and Peteet., D., 1988, The chronology of the last deglaciation: Implications for the cause of the Younger Dryas event: Paleoceanography, v. 3, p. 1-19.

Brown, D.A., 1984, Prospects and Limits of a Phytolith Key for Grasses in the Central United States: Journal of Archaeological Science, v. 11, p. 345-368.

Brydon, J.E., Dore, W.G., and Clark, J.S., 1963, Silicified Plant Asterosclereids Preserved in Soil: Soil Science Society of America Proceedings, v. 27, p. 476-477.

Bushue, L.J., Fehrenbacher, J.B., and Ray, B.W., 1974, Exhumed paleosols and associated modern till soils in western Illinois: Soil Science Society of America Proceedings, v. 34, p. 665-669.

Caspall, F.C., 1970, The spatial and temporal variations in loess deposition in northeastern Kansas: Unpublished Ph.D. dissertation, University of Kansas, 294 p.

Caspall, F.C., 1972, A note on the origin of the Brady paleosol in northeastern Kansas: Association of American Geographers Proceedings, v. 4, p. 19-24.

COHMAP members, 1988, Climatic changes of the last 18,000 years: observations and model simulations: Science, v. 241, p. 1043-1052.

Condra, G.E., Reed, E.C., and Gordon, E.D., 1947, Correlation of the Pleistocene deposits of Nebraska: Nebraska Geological Survey, Bulletin 15, 71 p.

Condra, G.E., and Reed, E.C., 1950, Correlation of the Pleistocene deposits of Nebraska (Revised): Nebraska Geological Survey, Bulletin 15A, 74 p.

Cornwell, K.J., 1987, Geomorphology and soils [Chap. 4]; in, Prehistoric and historic cultural resources of selected sites at Harlan County Lake, Harlan County, Nebraska, M.J. Adair and K.L. Brown, eds.: U.S. Army Corps of Engineers, p. 29-46.

Curry, B. B., and Follmer, L. R., 1992, The last interglacial-glacial transition in Illinois: 123-25 ka; in, The Last Interglacial-Glacial Transition in North America, P. U. Clark and P. D. Lea, eds.: Geological Society of America, Special Paper 270, p. 71-88.

Daniels, R.B., Handy, R.L., and Simonson, G.H., 1960, Dark colored bands in the thick loess in western Iowa: Journal of Geology, v. 67, p.450-458.

Dansgaard, W., Clausen, H. B., Gundestrup, N., Johnsen, S. J.,and Rygner, C., 1985, Dating and climatic interpretation of two deep Greenland ice cores: American Geophysical Union Geophysical Monograph, v. 33, p. 71-76.

Deevey, E.S., and Flint, R.F., 1957, Postglacial Hypsithermal Interval: Science, v. 125, p. 182-184.

Deines, P., 1980, The isotopic composition of reduced organic carbon, in Handbook of Environmental Isotope Geochemistry, v. 1: The Terrestrial Environment: Elsevier, p. 329-406.

Diekmeyer, E.C., 1994, Characterizations and paleoclimatic inferences from the post-Illinoian stratigraphic sequences at two central Great Plains sites: Unpublished M.A. thesis, University of Kansas, 84 p.

Diester-Haass, L., Schrader, H.J., and Thiede, J., 1973, Sedimentological and paleoclimatological investigation of two pelagic-ooze cores off Cape Barbas, northwest Africa: Meteor Forschung-Ergebnisse, v. 16, p. 19-66.

Dort, W., Jr., 1996, Unpublished 14C age and δ13C data from the Sargent site, southwestern Nebraska: University of Kansas.

Dreeszen, V.H., 1970, The stratigraphic framework of Pleistocene glacial and periglacial deposits in the Central Plains; in, Pleistocene and Recent Environments of the Central Great Plains, W. Dort, Jr., and J.K. Jones, Jr., eds.: University Press of Kansas, p. 9-22.

Fairbridge, R.W., 1983, The Pleistocene-Holocene boundary: Quaternary Science Reviews, v. 1, p. 215-244.

Feng, Z-D, 1991, Temporal and spatial variations in the loess depositional environment of central Kansas during the past 400,000 years: Unpublished Ph.D. dissertation, University of Kansas, 250 p.

Feng, Z-D, Johnson, W.C., Sprowl, D.R., and Lu, Y-C., 1994, Loess accumulation and soil formation in central Kansas, United States, during the past 400,000 years: Earth Surface Processes and Landforms, v. 19, p. 55-67.

Follmer, L.R., 1978, The Sangamon soil in its type area: a review; in, Quaternary Soils, W.C. Mahaney, ed.: Geo Abstracts Limited, p. 125-165.

Follmer, L.R., 1979, A historical review of the Sangamon soil; in, Wisconsinan, Sangamonian, and Illinoian stratigraphy in central Illinois: Illinois State Geological Survey, Guidebook 13, p. 79-91.

Follmer, L.R., 1982, The geomorphology of the Sangamon surface: it spatial and temporal attributes; in, Space and time in geomorphology, C.E. Thorn, ed.: Allen and Unwin, p. 117-146.

Follmer, L.R., 1983, Sangamon and Wisconsinan Pedogenesis in the Midwestern United States; in, Late-Quaternary Environments of the United States, Volume 1. The Late Pleistocene, S.C. Porter, ed.: University of Minnesota Press, p. 138-144.

Forman, S.L., 1990a, Chronologic evidence for multiple episodes of loess deposition during the Wisconsinan and Illinoian in the mid-continent, U.S.A. (abst.): Geological Society of America, Abstracts with Programs, v. 22, n. 7, p. A86.

Forman, S.L., 1990b, Thermolumenescence and radiocarbon chronology of loess deposition at the Loveland paratype, Iowa; in, Holocene Alluvial Stratigraphy and Selected aspects of Quaternary History of Western Iowa, E.A. Bettis, III, ed.: University of Iowa Quaternary Studies Group Contribution, No. 36, p. 165-172.

Forman, S.L., Bettis, E.A., Kemmis, T.L., and Miller, B.B., 1992, Chronological evidence for multiple periods of loess deposition during the late Pleistocene in Missouri and Mississippi River valleys, United States--implications for the activity of the Laurentide Ice Sheet: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 93, p. 71-83.

Fredlund, G.G., 1991, A comparison of Pleistocene and Holocene vegetation in the central Great Plains of North America: palynological evidence from Cheyenne Bottoms, Kansas: Unpublished Ph.D. dissertation, University of Kansas, 303 p.

Fredlund, G.G., 1993, Paleoenvironmental interpretations of stable carbon, hydrogen, and oxygen isotopes from opal phytoliths, Eustis Ash Pit, Nebraska: MASCA Research Papers in Science and Archeology, v. 10, p. 37-46.

Fredlund, G.G., 1995, Late Quaternary pollen record from Cheyenne Bottoms, Kansas: Quaternary Research, v. 43, p. 67-79.

Fredlund, G.G., and Jaumann, P.J., 1987, Late Quaternary palynological and paleobotanical records from the central Great Plains; in, Quaternary Environments of Kansas, W.C. Johnson, ed.: Kansas Geological Survey, Guidebook Series 5, p. 167-178. [available online]

Fredlund, G.G., Johnson, W.C., and Dort, W., Jr., 1985, A preliminary analysis of opal phytoliths from the Eustis ash pit, Frontier County, Nebraska: Nebraska Academy of Sciences, Institute for Tertiary-Quaternary Studies TER-QUA Symposium Series, v. 1, p. 147-162.

Frye, J.C., and Fent, O.S., 1947, The late Pleistocene loesses of central Kansas: Kansas Geological Survey Bulletin 70, part 3, p. 29-52. [available online]

Frye, J.C., and Leonard, A.B., 1949, Pleistocene stratigraphic sequence in northeastern Kansas: American Journal of Science, v. 247, p. 883-899.

Frye, J.C., and Leonard, A.B., 1951, Stratigraphy of late Pleistocene loesses of Kansas: Journal of Geology, v. 59, no. 4, p. 387-305.

Frye, J.C., and Leonard, A.B., 1952, Pleistocene geology of Kansas: Kansas Geological Survey, Bulletin 99, 230 p. [available online]

Frye, J.C., and Leonard, A.B., 1965, Quaternary of the southern Great Plains; in, The Quaternary of the United States-a review volume for VII Congress of the International Association for Quaternary Research, H.E. Wright, Jr. and D.G. Frey, eds.: Princeton University Press, p. 203-216.

Frye, J.C., and Willman, H.B., 1973, Wisconsinan climatic history. interpreted from Lake Michigan lobe deposits and soils; in, The Wisconsinan Stage, R.F. Black, R.P. Goldthwait, and H.B. Willman, eds.: Geological Society of America, Memoir 136, p. 135-152.

Frye, J.C., Leonard, A.B., Willman, H.B., Glass, H.D., and Follmer, L.R., 1974, The late Woodfordian Jules soil and associated molluscan faunas: Illinois State Geological Survey Circular 486, 11 p.

Frye, J.C., Willman, H.B., and Glass, H.D., 1968, Correlation of Midwestern loesses with the glacial succession; in, Loess and Related Eolian Deposits of the World, C.B. Schultz and J.C. Frye, eds.: Proceedings 7th Congress, International Association of Quaternary Research, University of Nebraska Press, p. 3-21.

Geis, J.W., 1973, Biogenic Silica in Selected Species of Deciduous Angiosperms: Soil Science, v. 116, p. 113-130.

Gould, F.W., and Shaw, R.B., 1968, Grass Systematics: Texas A and M University Press, 397 p.

Graham, R. W., 1987, Late Quaternary mammalian faunas and paleoenvironments of the southwestern plains of the United States; in, Late Quaternary Biogeography and Environments of the Great Plains and Prairies, R. W. Graham, H. A. Semken, Jr., and M.A. Graham, eds.: Illinois State Museum, p.24-86.

Grimm, E., 1992, Tiliagraph (software): Illinois State Museum.

Grilger, J., 1973, Studies on the late Quaternary vegetation history of northeastern Kansas: Geological Society of America, Bulletin, v. 84, p. 237-250.

Haas, H., Holliday, V., and Stuckenrath, R., 1986, Dating of Holocene stratigraphy with soluble and insoluble organic fractions at the Lubbock Lake archaeological site, Texas: an ideal case study: Radiocarbon, v., 28(2A), p. 473-485.

Hall, R.D., 1973, Sedimentation and alteration of loess in southwestern Indiana: Unpublished Ph.D. dissertation, Indiana University, 103 p.

Harrison, S.P., Kutzbach, J.E., Prentice, I.C., Behling, P.J., and Stykes, M.T., 1995, The response of Northern Hemisphere extratropical climate and vegetation to orbitally induced changes in insolation during the Last Interglacial: Quaternary Research, v. 43, p.174-184.

Heller, F., Liu X., Liu, T., Xu, T., 1991, Magnetic susceptibility of loess in China: Earth and Planetary Science Letters, v. 103, p. 301-310.

Heller, F., Shen, C. Beer, J., Liu, X., Liu, T., Bronger, A, Suter, M., Bonani, G., 1993, Quantitative estimates of pedogenic ferromagnetic mineral formation in Chinese loess and palaeoclimatic implications: Earth and Planetary Science Letters, v. 114, p. 385-390.

Hibbard, C.W., Frye, J.C., and Leonard, A.B., 1944, Reconnaissance of Pleistocene deposits in north-central Kansas: Kansas Geological Survey, Bulletin 52, part 1, p. 1-28. [available online]

Holliday, V.T., 1985, New data on the stratigraphy and pedology of the Clovis and Plainview sites, southern High Plains: Quaternary Research, v. 52, p. 388-402.

Holliday, V.T., 1989, Middle Holocene drought on the Southern High Plains: Quaternary Research, v. 31, p. 74-82.

Holliday, V.T., Johnson, E., Haas, H., and Stuckenrath, R., 1983, Radiocarbon ages from the Lubbock Lake site, 1950-1980: Framework for cultural and ecological change on the Southern High Plains: Plains Anthropologist, v. 28, p. 165-182.

Hopkins, D.M., 1975, Time-stratigraphic nomenclature for the Holocene Epoch: Geology, v. 3, p. 10.

Humphrey, J.D., and Ferring, C.R., 1994, Stable isotopic evidence for latest Pleistocene and Holocene climatic change in North-central Texas: Quaternary Research, v. 41, p. 200-213.

Johnson, D.L., 1992, Geomorphological survey and Geoarchaeological overview of Fort Riley, Riley and Geary Counties, Kansas: Unpublished report to U.S. Army Construction Engineering Laboratory, Champaign, Illinois.

Johnson, D.L., 1994, Geoarchaeological research on Fort Riley, Kansas: a dynamic paleoenvironmental model of late Quaternary landscape evolution: Unpublished report to U.S. Army Construction Engineering Research Laboratory, Champaign, Illinois.

Johnson, D.L., 1996, Geomorphological, pedological and geoarchaeological study of Fort Riley, Kansas: Unpublished report to U.S. Army Construction Engineering Research Laboratory, Champaign, Illinois.

Johnson, E., 1987, Paleoenvironmental overview; in, Lubbock Lake: Late Quaternary Studies on the Southern High Plains, E. Johnson, ed.: Texas A&M University Press, p. 90-99.

Johnson, W.C., 1989, Stratigraphy and late-Quaternary landscape evolution; in, Archaeological investigations at the North Cove site, Harlan County Lake, Harlan County, Nebraska, M.J. Adair, ed.: University of Kansas Office of Archaeological Research, p. 22-52.

Johnson, W.C., 1991, Buried soil surfaces beneath the Great Bend Prairie of central Kansas and archaeological implications: Current Research in the Pleistocene, v. 8, p. 108-110.

Johnson, W.C., 1993a (ed.), Second International Paleopedology Symposium Field Excursion: Kansas Geological Survey Open-file Report 93-30.

Johnson, W.C., 1993b, Surficial geology and stratigraphy of Phillips County, Kansas, with emphasis on the Quaternary Period: Kansas Geological Survey Technical Series 1. [available online]

Johnson, W.C., 1996a, Archaeological geology and geomorphology; in, The DB Site--Data Recovery Plan for a Stratified Prehistoric Upland Occupation, Fort Leavenworth, Kansas, B. Logan, ed.: University of Kansas Museum of Anthropology Project Report Series 96, p. 15-22.

Johnson, W.C., 1996b, Magnetic and stable isotope (13C) parameters as indicators of late-Quaternary environments on Fort Riley, Kansas: Kansas Geological Survey, Open-file Report 96-34.

Johnson, W.C., Bozarth, S., and Diekmeyer, E., 1994, Paleoenvironmental reconstruction via opal phytolith and carbon isotope analyses of late-Wisconsinan loess: geoarchaeological investigations on Fort Riley, Riley and Geary Counties, Kansas: Kansas Geological Survey, Open-file Report 94-38.

Johnson, W.C., and Logan, B., 1990, Geoarchaeology of the Kansas River Basin, central Great Plains; in, Archaeological Geology of North America, N.P. Lasca and J. Donahue, eds.: Geological Society of America, Decade of North American Geology Centennial Special Volume 4, p. 267-299.

Johnson, W.C., and Martin, C.W., 1987, Holocene alluvial-stratigraphic studies from Kansas and adjoining states of the east-central Plains; in, Quaternary environments of Kansas, W.C. Johnson, ed.: Kansas Geological Survey, Guidebook Series 5, p. 109-122. [available online]

Johnson, W.C., May, D.W., Diekmeyer, E., Farr, M.R., and Park, K., 1993a, Stop 12 Eustis Ash Pit; in, Second International Paleopedology Symposium Field Excursion, W.C. Johnson, ed.: Kansas Geological Survey, Open-File Report 93-30, p. 12/1-12/13

Johnson, W.C., May, D.W., and Mandel, R.D., 1996, A data base of alluvial radiocarbon ages from the central Great Plains (Kansas and Nebraska): Current Research in the Pleistocene, v. 13, p. 79-80.

Johnson, W.C., Park, K., Diekmeyer, E., and Muhs, D.R., 1993b, Chronology, stratigraphy, and depositional environment of the late Wisconsin (Peoria) Loess of Kansas and Nebraska: Geological Society of America, Abstracts with Programs, v. 25, p. 59.

Johnson, W.C., and Muhs, D.R., 1996, A revised chronology of loess exposed at the Barton County sanitary landfill, Kansas, based on recent thermoluminescence and radiocarbon ages: Unpublished manuscript.

Johnson, W.C., and Valastro, S., 1994, Laboratory preparation of soil and sediment samples for radiocarbon dating of humates (total, humic acid, and humin fractions): Kansas Geological Survey, Open-file Report 94-50.

Kapp, R.O., 1965, Illinoian and Sangamon vegetation in southwestern Kansas and adjacent Oklahoma: Contributions from the Museum of Paleontology, University of Michigan, v. 19, p. 167-255.

Kapp, R.O., 1970, Pollen analysis of pre-Wisconsinan sediments; in, Pleistocene and Recent environments of the central Great Plains, W. Dort, Jr., and J.K. Jones, eds.: University of Kansas Press, p. 143-155.

Klein, R.L., and Geis, J.W., 1978, Biogenic Silica in the Pinaceae: Soil Science, v. 126, p. 145-155.

Kleiss, H.J. and Fehrenbacher, J.G., 1973, Loess distribution as revealed by mineral variations: Soil Science Society of America Proceedings, v. 37, p. 291-95.

Krishnamurthy, R.V., DeNiro, M.J., and Pant, R.K., 1982, Isotope evidence for Pleistocene climatic changes in Kashmir, India: Nature, v. 298, p. 640-641.

Kuchler, A W., 1972, The oscillation of the mixed prairies in Kansas: Erdkunde, v. 26, p. 120-129.

Kuchler, A W., 1974, A New Vegetation Map of Kansas: Ecology, v. 55, p. 586-604.

Kukla, G.J., 1977, Pleistocene land-sea correlations, I, Europe. Earth-Science Review, v. 13, p. 307-374.

Kukla, G.J., 1987, Loess stratigraphy in central China: Quaternary Science Reviews, v. 6, p. 191-219.

Kurmann, M.H., 1981, An opal-phytolith and palynomorph study of extant and fossil soils in Kansas: Unpublished M.S. thesis, Kansas State University, 81 p.

Kurmann, M.H., 1985, An opal-phytolith and palynomorph study of extant and fossil soils in Kansas (U.S.A): Palaeogeography, Palaeoclimatology, and Palaeoecology, v. 49, p. 217-235.

Kutzbach, J.E., 1981, Monsoon climate of the early Holocene: climatic experiment with the Earth's orbital parameters for 9,000 years ago: Science, v. 214, p. 61.

Kutzbach, J.E., 1985, Modeling of paleoclimates: Advances in Geophysics, v. 28A, p. 159-196.

Kutzbach, J.E., 1987, Model simulations of the climatic patterns during the deglaciation of North America; in, North America and adjacent oceans during the last deglaciation, W. F. Ruddiman and H. E. Wright, Jr., eds.: Geological Society of America, The Geology of North America, v. K-3, p. 425-446.

Leonard, A.B., 1951, Stratigraphic zonation of the Peoria Loess in Kansas: Journal of Geology, v. 59, p. 323-332.

Leonard, A.B., 1952, Illinoian and Wisconsinan molluscan faunas m Kansas: Kansas University Paleontological Contributions, Mollusca (Article 4), 38 p. [available online]

Leonard, A.R., 1952, Geology and ground-water resources of the North Fork Solomon River in Mitchell, Osborne, Smith, and Phillips Counties, Kansas: Kansas Geological Survey, Bulletin 98, 150 p.

Leverett, F., 1899, The Illinois Glacial Lobe: U.S. Geological Survey Monograph 38.

Libby, W.F., 1955, Radiocarbon dating: The University of Chicago Press, 175 p.

Lu, H., Wu, N., Nie, G., and Wang, Y., 1991, Phytolith in loess and its bearing on paleovegetation; in, Loess, Environment and Global Change, T. Liu,, ed.: Science Press, Beijing, p.112-123.

Lutenegger, A. J., 1985, Desert loess in the Midcontinent, U.S.A. (abst.): First International Conference on Geomorphology, Manchester, Abstracts of Papers, p. 378.

Maat, P., and Johnson, W.C., 1996, Thermoluminescence and new 14C age estimates for late Quaternary loesses in Southwestern Nebraska: Geomorphology, v. 17, p. 115-128.

Mandel, R.D., 1995, Geomorphic controls of the Archaic Record in the Central Plains of the United States; in, Bettis, E.A., III, ed., Archaeological Geology of the Archaic Period in North America: Geological Society of America, Special Paper 297, p. 37-66.

Martin, C.W., 1990, Late Quaternary Landform Evolution in the Republican River Basin, Nebraska: Unpublished Ph.D. dissertation, University of Kansas, 289 p.

Martin, C.W., and Johnson, W.C., 1995, Variation in radiocarbon ages of soil organic matter fractions from late Quaternary buried soils: Quaternary Research, v. 43, p. 232-237.

Martinson, D.G., Pisias, N.G., Hays, J.D., Imbrie, J., Moore, T.C., Jr., and Shackleton, N.J., 1987, Age dating and the orbital theory of the Ice Ages--development of a high-resolution 0 to 300,000 year chronology: Quaternary Research, v. 27, p.1-29.

May, D.W., personal communication, Department of Geography, University of Northern Iowa, Cedar Falls.

May, D.W., 1989, Age and distribution of the Todd Valley Formation in the lower South Loup River valley (abstract): Proceeding of the Nebraska Academy of Sciences, p. 53.

May, D.W., 1991, The stratigraphic context offractured mammoth bones at the La Sena site (25FT177), Harry Strunk Lake (Medicine Creek Reservoir), Nebraska: Unpublished report to Department of Anthropology, University of Nebraska, Lincoln, Nebraska, 25 p.

May, D.W., and Holen, S.R., 1993, Radiocarbon ages of soils and charcoal in late-Wisconsinan loess in south-central Nebraska: Quaternary Research, v. 39, p. 55-58.

May, D.W., and Souders, V.L., 1988, Radiocarbon ages for the Gilman Canyon Formation in Dawson County, Nebraska, (abs.): Nebraska Academy of Sciences, Proceedings, p. 47-48.

McCraw, D.J., and Autin, W.J., 1989, Lower Mississippi Valley loesses--Field Guide, 1989 Mississippi Valley Loess Tour: INQUA Commission on Loess and the North American Loess Working Group.

McKay, E.D., 1979a, Stratigraphy of Wisconsinan and older loesses in southwestern Illinois in Geology of western Illinois: Illinois State Geological Survey, Guidebook 14, p. 37-67.

McKay, E.D., 1979b, Stratigraphy of Wisconsinan and older loesses in southwestern Illinois in Geology of Western Illinois: Illinois State Geological Survey, Guidebook 14, p. 37-67.

Mix, A.C., 1987, The oxygen-isotope record of glaciation; in, North America and adjacent oceans during the last deglaciation, W. F. Ruddiman and H. E. Wright, Jr., eds.: Geological Society of America, The Geology of North America, v. K3, p. 111-135.

Mörner, N.-A., 1976, The Pleistocene-Holocene boundary: a proposed boundary-stratotype in Gothenburg, Sweden: Boreas, v. 5, p. 193-275.

Morrison, R.B., 1965, Principles of Quaternary soil stratigraphy; in, Quaternary soils, R.B. Morrison and H.E. Wright, Jr., eds.: INQUA VII Congress Proceedings, v. 9, p. 1-69.

Morrison, R.B., 1987, Long-term perspective: changing rates and types of Quaternary surficial processes: erosion-deposition-stability cycles; in, Geomorphic systems of North America, W.L. Graf, ed.: Geological Society of America, Decade of North American Geology Centennial Special Volume 2, p. 167-176.

Muhs, D.R., Bettis, E.A., III, Johnson, W.C., Rutledge, E.W., Maat, P.B., and Stafford, T.W., 1996, Pedologic evidence for the climate of the Last Interglacial Period in the Midcontinent of the United States (abst.): Geological Society of America, Abstracts with Programs, v. 28, no. 7, p. A251.

Muhs, D.R., Bush, C.A., Cowherd, S.D., and Mahan, S., 1995, Geomorphic and geochemical evidence for the source of sand in the Algodones dunes, Colorado Desert, southeastern California; in, Desert Aeolian Processes, V.P. Tchakerian, ed.: Chapman and Hall, London, 326 p..

Muhs, D.R., Bush, C.A., Stewart, K.C., and Crittenden, R.C., 1990, Geochemical evidence of Saharan dust parent material for soils developed on Quaternary limestones of Caribbean and western Atlantic islands: Quaternary Research, v. 33, p. 157-177.

Muhs, D.R., and Johnson, W.C., 1996, Trace-element ratios as an indication of weathering in the Sangamon soil at the Eustis ash pit, southwestern Nebraska: Unpublished manuscript.

Mulholland, S.C., and Rapp, G., Jr., 1992, A Morphological Classification of Grass Silica-Bodies; in, Phytolith Systematics, G. Rapp, Jr., and S.C. Mulholland, eds.: Plenum Press, p. 65-89.

Norgren, J., 1973, Distribution, Form and Significance of Plant Opal in Oregon Soils: Unpublished Ph.D. dissertation, Department of Soil Science, Oregon State University, 176 p.

North American Commission on Stratigraphic Nomenclature, 1983, North American Stratigraphic Code: American Association of Petroleum Geologists Bulletin, v. 67, p. 841-875.

Osborn, G., Clapperton, C., Davis, P.T., Reasoner, M., Rodbell, D.T., Seltzer, G.O., and Zielinski, G., 1995, Potential glacial evidence for the Younger Dryas event in the Cordillera of North and South America: Quaternary Science Reviews, v. 14, p. 823-832.

Oviatt, C.G., Karlstrom, E.T., and Ransom, M.D., 1988, Pleistocene loess, buried soils, and thermoluminescence dates in an exposure near Milford Lake, Geary County, Kansas (abst.): Geological Society of America, Abstracts with Programs, v. 20, p. 125-126.

Paterson, W.S.B., and Hammer, C.U., 1987, Ice core and other glaciological data; in, North America and adjacent oceans during the last deglaciation, W. F. Ruddiman and H. E. Wright, Jr., eds.: Geological Society of America, The Geology of North American, v. K-3, p. 91-109.

Pease, D.S., 1967, Opal Phytoliths as Indicators of Paleosols: Unpublished M.S. thesis, New Mexico State University, 81 p.

Peteet, D., Rind, D., and Kukla, G., 1992, Wisconsinan ice-sheet initiation: Milankovitch forcing, paleoclimatic data and global climate modeling; in, The Last Interglacial-Glacial Transition in North America, P. U. Clark and P. D. Lea, eds.: Geological Society of America, Special Paper 270, p. 53-69.

Pierce, H.G., 1987, the gastropods, with notes on other invertebrates; in, Lubbock Lake: Late Quaternary Studies on the Southern High Plains, E. Johnson, ed.: Texas A&M University Press, p. 41-48.

Piperno, D.R., 1988, Phytolith Analysis--An Archaeological and Geological Perspective: Academic Press, 280 p.

Pohl, R.W., 1968, How to Know the Grasses--The Pictured Key Nature Series: Wm. C. Brown Company Publishers, 200 p.

Reed, E.C., and Dreeszen, V.H., 1965, Revision of the classification of the Pleistocene deposits of Nebraska: Nebraska Geological Survey, Bulletin 23, 65 p.

Reheis, M.C., 1990, Influence of climate and eolian dust on the major-element chemistry and clay mineralogy of soils in the northern Bighorn Basin, U.S.A.: Catena, v. 17, p. 219-248.

Richmond, G.M., and Fullerton, D.S., 1986a, Introduction to Quaternary glaciations in the United States of America; in, V. Sibrava, D.Q. Bowen, and G.M. Richmond, eds., Quaternary Glaciations in the Northern Hemisphere: Quaternary Science Reviews, v. 5, 3-10 p.

Richmond, G.M., and Fullerton, D.S., 1986b, Summation of Quaternary glaciations in the United States of America; in, V. Sibrava, D.Q. Bowen, and G.M. Richmond, eds., Quaternary Glaciations in the Northern Hemisphere: Quaternary Science Reviews, v. 5, p. 183-196.

Rovner, I., 1971, Potential of Opal Phytoliths for Use in Paleoecological Reconstruction: Quaternary Research, v. 1, p. 343-359.

Rovner, I., 1975, Plant Opal Phytolith Analysis in Midwestern Archaeology: Michigan Academician, v. 8, p. 129-137.

Ruddiman, W.F., 1987, Synthesis; the ocean/ice sheet record; in, North America and adjacent oceans during the last deglaciation, W. F. Ruddiman and H. E. Wright, Jr., eds.: Geological Society of America, The Geology of North America, v. K-3, p. 463-478.

Ruhe, R.V., 1956, Geomorphic surfaces and the nature of soils: Soil Science, v. 82, p. 441-455.

Ruhe, R.V., 1969, Quaternary landscapes in Iowa: Iowa State University Press, 255 p.

Ruhe, R.V., 1976, Stratigraphy of midcontinental loess, U.S.A.; in, Quaternary Stratigraphy of North America, W.C. Mahaney, ed.: Dowden, Hutchinson, and Ross, Stroudsburg, PA, p. 197-211.

Ruhe, R.V., 1983, Depositional environment of late Wisconsin loess in the Midcontinental United States; in, Late-Quaternary Environments of the United States, Volume 1. The Late Pleistocene, S.C. Porter, ed.: University of Minnesota Press, p. 130-137.

Ruhe, R.V., Hall, R.D., and Canepa, A.P., 1974, Sangamon paleosols of southwestern Indiana, USA: Geoderma, v. 12, p. 191-200.

Ruhe, R.V., Miller, G.A., and Vreeken, W.J., 1971, Paleosols, loess sedimentation, and soil stratigraphy; in, Paleopedology--origin, nature, and dating of paleosols, D.H. Yaalon, ed.: Hebrew University Press, p. 41-60.

Ruhe, R.V., and Olson. C.G., 1980, Clay-mineral indicators of glacial and nonglacial sources of Wisconsinan loesses in southern Indiana, U.S.A: Geoderma, v. 24, p. 283-97.

Schaetzl, C.B., 1986, The Sangamon paleosol in Brown County, Kansas: Kansas Academy of Science Transactions, v. 89, p. 152-161.

Schultz, C.D., Lueninghoener, G.C., and Frankforter, W.D., 1951, A graphic resume of the Pleistocene of Nebraska (with notes on the fossil mammalian remains): University of Nebraska State Museum Bulletin, v. 3(6), p. 1-41.

Schultz, C.D., and Martin, L.C., 1970, Quaternary mammalian sequence in the central Great Plains; in, Pleistocene and Recent Environments of the Central Great Plains, W. Dort, Jr., and J.K. Jones, Jr., eds.: University of Kansas Press, p. 341-353.

Schultz, C.D., and Stout, T.M., 1945, Pleistocene loess deposits of Nebraska: American Journal of Science, v. 243, p. 231-244.

Schultz, C.D., and Stout, T.M., 1948, Pleistocene mammals and terraces in the Great Plains: Geological Society of America, Bulletin, v. 59, p. 553-591.

Schultz, C.D., and Tanner, L.G., 1957, Medial Pleistocene fossil vertebrate localities in Nebraska: University of Nebraska State Museum Bulletin, v. 4, p. 59-81.

Semken, H.A., 1983, Holocene mammalian biogeography and climatic change in the eastern and central United States; in, Wright, H.E. Jr., ed., Late Quaternary environments of the United States, Volume 2, The Holocene: University of Minnesota Press, p. 182-207.

Simonson, R.W., 1941. Studies of buried soils formed from till in Iowa: Soil Science Society of America Proceedings, v. 6, p. 373-381.

Souders, V.L., and Kuzila, M.S., 1990, A report on the geology and radiocarbon ages of four superimposed horizons at a site in the Republican River Valley, Franklin County, Nebraska (abst.): Nebraska Academy of Sciences Proceedings, p. 65.

Taylor, R,E., 1987, Radiocarbon Dating--An Archaeological Perspective: Academic Press, 212 p.

Thorpe, J., Johnson, W.M., and Reed, E.C., 1951, Some post-Pliocene buried soils of central United States: Journal of Soil Science, v. 2, p. 1-22.

Tien, P.L., 1968, Differentiation of Pleistocene deposits in northeastern Kansas by clay minerals: Clay and Clay Mineralogy, v. 16, p. 99-107.

Tomanek, G.W., and Hulett, G.H., 1970, Effects of historical droughts on grassland vegetation in the central Great Plains; in, Pleistocene and Recent Environments of the Central Great Plains, W. Dort, Jr., and J.K. Jones, Jr., eds.: University of Kansas Press, p. 203-211.

Twiss, P.C., 1980, Opal phytoliths as indicators of C3 and C4 grasses: Geological Society of America, Abstracts with Programs, v. 12, p. 7.

Twiss, P.C., 1983, Dust deposition and opal phytoliths in the Great Plains; in, Man and the Changing Environments in the Great Plains, W.H. Caldwell et al., eds.: Nebraska Academy of Sciences Transactions, v. 11, p. 73-82.

Twiss, P.C., 1987, Grass-Opal Phytoliths as Climatic Indicators of the Great Plains Pleistocene; in, Quaternary Environments of Kansas, W.C. Johnson, ed.: Kansas Geological Guide Book Series 5, p. 179-188.

Twiss, P.C., Suess, E., and Smith, R.M., 1969, Morphological classification of grass phytoliths: Soil Science Society of America Proceedings, v. 33, p. 105-115.

Van Zant, K.L., 1979, Late glacial and postglacial pollen and plant macrofossils from Lake West Okoboji, northwestern Iowa: Quaternary Research, v. 12, p. 358-380.

Watson, R.A., and Wright, H.E., Jr., 1980, The end of the Pleistocene: a general critique of chronostratigraphic classification: Boreas, v. 9, p. 153-163.

Watts, W.A., and Wright, H.E., Jr., 1966, Late-Wisconsin pollen and seed analysis from the Nebraska Sand Hills: Ecology, v. 47, p. 202-210.

Webb, T., III, Cushing, E.J., and Wright, H.E., Jr., 1983, Holocene changes in the vegetation of the Midwest; in, Late Quaternary Environments of the United States, v. 2, The Holocene H.E. Wright, Jr., ed.: University of Minnesota Press, p. 142-165.

Welch, J.E., and Hale, J.M., 1987, Pleistocene loess in Kansas; Status, present problems, and future considerations; in, Quaternary Environments of Kansas, W.C. Johnson, ed.: Kansas Geological Survey, Guidebook Series 5, p. 67-84. [available online]

Wells, P.V., and Stewart, J.D., 1987, Cordilleran-boreal taiga and fauna on the central Great Plains of North America, 14,000-18,000 years ago: The American Midland Naturalist, v. 118, p. 94-106.

Wilding, L.P., and Drees, L.R., 1971, Biogenic Opal in Ohio Soils: Soil Science of America Proceedings, v. 35, p. 1004-1010.

Wilding, L.P., and Drees, L.R., 1973, Scanning Electron Microscopy of Opaque Opaline Forms Isolated from Forest Soils in Ohio: Soil Science Society of America Proceedings, v. 37, p. 647-650.

Wilding, L.P., and Drees, L.R., 1974, Contributions of Forest Opal and Associated Crystalline Phases of Fine Clay Fractions of Soils: Clays and Clay Minerals, v. 22, p.295-306.

Wilding, L.P., Smeck, N.E., and Drees, L.R., 1977, Silica in Soils: Quartz, Cristobalite, Tridymite, and Opal; in, Minerals in Soils Environment, J.B., Dixon and S.B. Weed, eds.: Soil Science Society of America, p. 471-552.

Wilding, L.P., Smeck, N.E., and Drees, L.R., 1979, Dissolution and Stability of Biogenic Opal: Soil Science Society of America Journal, v. 43, p. 800-802.

Willman, H.B. and Frye, J.C., 1970, Pleistocene stratigraphy of Illinois: Illinois State Geological Survey Bulletin 94, 204 p.

Wright, H.E., Jr., 1970, Vegetational history of the Central Plains; in, Pleistocene and Recent Environments of the Central Great Plains, W. Dort, Jr., and J.K. Jones, Jr., eds.: University of Kansas Press, p. 157-172.

Zhou, W., An, Z., and Mead, M.J., 1994, Stratigraphic division of Holocene loess in China: Radiocarbon, v. 36, p. 37-45.


Results

Kansas Geological Survey, Geology
Placed online Aug. 10, 2012
Comments to webadmin@kgs.ku.edu
The URL for this page is http://www.kgs.ku.edu/Publications/OFR/1996/OFR96_35/page3.html