Mississippian rocks are widely exposed in the Midcontinent and have been studied locally and regionally in great detail. Outcrops in Kansas are confined to a small area of less than two townships in Cherokee County in the extreme southeastern part of the State. Westward, the Mississippian rocks in Kansas are preserved in basinal areas and are the source of much oil and gas. Accelerated exploration for petroleum reserves in Kansas in recent years has vastly increased the information on Mississippian rocks. The new data include cores and improved electrical, radioactivity, acoustical, and mechanical logs.
Early workers, such as Lee (1940), worked mostly with cable tool samples and used hydrochloric acid insoluble residues in establishing equivalence of Mississippian rocks in Kansas with outcrops in Missouri and in the type section in the upper Mississippi River Valley. When acetic acid is used to digest carbonate rocks, phosphatic material is preserved. Collinson, Scott, and Rexroad (1962) used this recovery technique for conodonts in rocks from the type area of the Mississippian. Thompson and Goebel (1963), in a pilot study of conodonts, used acetic acid on cores of dominantly Meramecian carbonates from western Kansas.
It was judged that the definitive lithic features and the distribution of conodont zones in the Meramecian in Kansas were best tested by studies of cores. This investigation was primarily concerned with and based upon information gained from the study of cores. Drilling companies seldom take long cores. It was necessary, therefore, to assemble a collection of cores, in order to provide a complete Meramecian section.
Although abundant in certain parts of the Meramecian rocks, megafossils, because of their larger size and limited occurrence, have not been used extensively in delineating biostratigraphic zones in the subsurface Mississippian rocks in Kansas. Use of conodonts as guide fossils within the type area of the upper Mississippi River Valley demonstrates the practicality of these forms as tools for correlation. Phylogenetic relationships of the conodonts are controversial. These fossils constitute one of the more important groups of microfossils used as guide fossils. Conodonts have special significance because they are found in a wide variety of depositional environments and are, therefore, useful in correlating facies.
Some of the cores used in a preliminary study of conodonts from western Kansas Meramecian rocks (Thompson and Goebel, 1963) were restudied by Thompson (1965) and Goebel (1966, 1968a). Thompson described and appraised the Meramecian conodont fauna of all of Kansas, and Goebel reported on the stratigraphy of western Kansas Mississippian rocks. This paper incorporates the findings of these two investigations of the Meramecian Stage in Kansas.
Special thanks are extended to the late Louise Jordan, Oklahoma Geological Survey, who made Sinclair Research Company cores available to the State Geological Survey of Kansas and the authors, and Mobil Oil Company for their contribution of cores. Other cores on file at the State Geological Survey of Kansas Well Core Library were utilized, also.
Acknowledgment is extended to Brian F. Glenister, Department of Geology, University of Iowa; Charles W. Collinson, Illinois State Geological Survey; and Carl B. Rexroad, Indiana State Geological Survey, for their interest and assistance and to H. Andrew Ireland, Department of Geology, The University of Kansas.
An attempt was made to secure cores of Meramecian rocks from all portions of the State. The material was chosen for its stratigraphic interval and geographic distribution. The locations of materials used in this study are shown in Figure 1.
Figure 1--Index map of Kansas, showing early Pennsylvanian structural features and distribution (letters) of cores studied. Locations are listed in Table 1, distribution of conodonts in the Appendix.
Many cores (Table 1) were available from the Hugoton embayment (wells A-1), so only those that enabled complete coverage of the Meramecian section in that region were chosen, care being taken to secure as complete a geographic distribution over the area of the embayment as possible. Three of the cores were originally studied by Thompson and Goebel (1963) for their conodont content: No. 1-A Mark (C), No. 1 Watchorn (D), and No. 1 Collins (F). Sampling procedures were improved by utilizing half of the core (pilot study consisted of 200-gm samples at 1-foot intervals). A higher conodont yield from these cores was expected and achieved.
Table 1--Registry of cores from Meramecian rocks. Letters refer to cores in Figure I and in the Appendix. (The number of samples processed and identifiable specimens recovered from each well or outcrop are listed in parentheses after their locations.)
|A||No. 1 Cunningham Est., Mobil Oil Co., C SW SE sec. 13, T 34 S, R 37 W, Stevens County, Kansas (19 samples, 172 specimens).|
|B||No. 1 Kells "B," Cities Service Oil Co., C NW NW sec. 5, T 28 S, R 34 W, Haskell County, Kansas (58 samples, 77 specimens).|
|C||No. 1-A Mark, Atlantic Oil Co., SE SE SE sec. 28, T 20 S, R 33 W, Scott County, Kansas (34 samples, 38 specimens).|
|D||No. 1 Watchorn, Alma Oil Co., and Robert B. McNeeley, C SW NE sec. 13, T 15 S, R 33 W, Logan County, Kansas (65 samples, 40 specimens).|
|E||No. 1 Winans, Mobil Oil Co., C SE NW sec. 32, T 20 S, R 27 W, Lane County, Kansas (30 samples, 38 specimens).|
|F||No. 1 Collins, Mid-Continent Petrol. Corp., C NW NW sec. 24, T 20 S, R 26 W, Ness County, Kansas (31 samples, 117 specimens),|
|G||No. 1 Elsasser Heirs, Mobil Oil Co., C Sl~' SW sec. 29, T 18 S, R 22 W, Ness County, Kansas (31 samples, 147 specimens).|
|H||No. 1 Matkin, Mull Drlg. Co., Mobil Oil Co., C NE NW sec. 16, T 27 S, R 21 W, Ford County, Kansas (23 samples, 127 specimens).|
|I||No. 1 Exchange Bank, Sinclair-Prairie Oil Co., C SE SW sec. 27, T 33 S, R 19 W, Comanche County, Kansas (61 samples, 127 specimens).|
|J||No. 1 Colburn "A," Sinclair Oil and Gas Co., NE SW NE sec. 9, T 33 S, R 11 W, Barber County, Kansas (33 samples, 41 specimens).|
|K||No. 1 Helmley, Sinclair Oil and Gas Co., SW SW SE sec. 3, T 35 S, R 10 W, Barber County, Kansas (36 samples, 217 specimens).|
|L||No. 1 Wolfje, Kessler and Their, Inc., C SW SW NE sec. 17, T 33 S, R 6 W, Harper County, Kansas (9 samples, specimens) [Note: well name is actually Woltje].|
|M||No. 1 Dalton "B," Western Petroleum Co., SW NE SE sec. 11, T 24 S, R 12 E, Greenwood County, Kansas (52 samples, 120 specimens).|
|N||No. 6 H. G. Collins, Sinclair Oil and Gas Co., C SE NE sec. 30, T 23 S, R 14 E, Woodson County, Kansas (29 samples, 107 specimens).|
|O||No. 12 W. P. Headley "A," Sinclair Oil and Gas Co., C W2 SE NW NW sec. 32, T 23 S, R 14 E, Woodson County, Kansas (28 samples, 270 specimens).|
|P||Mississippian outcrop, SE NW sec. 1, T 35 S, R 25 E, Cherokee County. Kansas (13 samples, 56 specimens).|
|Q||Mississippian outcrop; NE NE SW sec. 33, T 34 S, R 25 E, Cherokee County, Kansas (10 samples, 21 specimens).|
The central portion of the State presented a more difficult problem in selection of material. No cores were available from the Salina basin. All cores chosen from the Sedgwick basin were from the area containing the "Cowley Formation" of Lee (1940). In this south-central region there is generally no differentiation by lithostratigraphic units between Osagian and Meramecian rocks. Wells J-L are from the Sedgwick basin.
Material available from the Forest City basin of northeastern Kansas was judged not suitable for this investigation. Several cores (M-O) and samples from two outcrops (P and Q) in the Cherokee basin were utilized.
Both cores and outcrops were sampled in an attempt to recover Meramecian conodonts (Table 1), and cores were studied for lithology.
Kansas Geological Survey, Geology
Placed on web June 24, 2010; originally published Dec. 1968.
Comments to email@example.com
The URL for this page is http://www.kgs.ku.edu/Publications/Bulletins/192/02_intro.html