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Wisconsinan, Sangamonian, and Illinoian Stratigraphy in Central Illinois

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Wisconsinan, Sangamonian, and Illinoian Stratigraphy in Central Illinois MIDWEST FRIENDS OF THE PLEISTOCENE 26th FIELD CONFERENCE May 4-6, 1979 Wisconsinan, Sangamonian, and Illinoian stratigraphy in central Illinois LEADERS: Leon R. Follmer E. Donald McKay Jerry A. Lineback David L. Gross CONTRIBUTIONS BY: Jerry A. Lineback Leon R. Follmer H. B. Willman E. Donald McKay James E. King Frances B. King Norton G. Miller Sponsored by: Illinois State Geological Survey, Urbana, Illinois, and Department of Geology, University of Illinois at Urbana-Champaign ILLINOIS STATE GEOLOGICAL SURVEY GUIDEBOOK 13 LOCATIONS OF GEOLOGIC SECTIONS AND FIELD TRIP ROUTE Wisconsinan, Sangamonian, and Illinoian stratigraphy in central Illinois contents Dedication ;|; Acknowledgments 1 INTRODUCTION 1 REGIONAL STRATIGRAPHY 5 Pre-lllinoian drift 5 Illinoian drift 5 Wisconsinan drift 6 LABORATORY DATA AND TECHNIQUES 7 DESCRIPTIONS OF SECTIONS 7 Farm Creek Section 19 Gardena Section 24 Farmdale Park Section 29 Glendale School Section 31 GraybaR Section 35 Tindall School Section 39 Lewistown Section 43 Arenzville Section 49 Fairground Section 54 Athens South Quarry Section 60 Athens North Quarry Section 65 Jubilee College Section 69 THE STATUS OF THE ILLINOIAN GLACIAL STAGE Jerry A. Lineback 79 A HISTORICAL REVIEW OF THE SANGAMON SOIL Leon R. Follmer 92 COMMENTS ON THE SANGAMON SOIL H. B. Willman 95 WISCONSINAN LOESS STRATIGRAPHY OF ILLINOIS E. Donald McKay 109 POLLEN ANALYSIS OF SOME FARMDALIAN AND WOODFORDIAN DEPOSITS, CENTRAL ILLINOIS James E. King 114 PLANT MACROFOSSILS FROM THE ATHENS NORTH QUARRY Frances B. King 116 PALEOECOLOGICAL COMMENTS ON FOSSIL MOSSES IN A BURIED ORGANIC BED NEAR PEORIA, TAZEWELL COUNTY, ILLINOIS Norton G. Miller 117 APPENDIXES 117 Appendix 1 Grain sizes, carbonate minerals, and clay mineralogy 126 Appendix 2 Pipette analysis data 129 Appendix 3 Explanation of the pedologic features and concepts used in the discussion of soils 135 REFERENCES Midwest Friends of the Pleistocene Field Conference, 26th, 1979. Wisconsinan, Sangamonian, and lllinoian stratigraphy in central Illinois : Midwest Friends of the Pleistocene 26th Field Conference, May 4-6, 1979 / contributions by Jerry A. Lineback . .. et al.; sponsored by Illinois State Geological Survey, Urbana, Illinois, and Department of Geology, Univer- sity of Illinois at Urbana-Champaign. - Urbana : The Survey, 1979. - 140p. : ill. ; 28cm. - (Guidebook Illinois. State Geo- logical Survey ; 1 3) Bibliography: p. 135-139. 1. Geology, Stratigraphic-Quaternary-Guide-books. 2. Geology- Illinois-Guide-books. I. Lineback, Jerry A. II. Illinois. State Geo- logical Survey. III. Illinois. University at Urbana-Champaign. Dept. of Geology. IV. Title. V. Series: Illinois. State Geological Survey. Guidebook ; 13. Dedicated to Harold Bowen Willman in recognition of outstanding contributions to knowledge of Pleistocene geology, and in appreciation for more than a half century of service to the geological profession and for loyalty as a Friend. Midwest Friends of the Pleistocene May 5, 1979 ACKNOWLEDGMENTS A considerable amount of knowledge of the Pleistocene geology of Illinois has been achieved through the work of H. B. Willman, J. C. Frye, H. D. Glass, and many others on the staff of the Illinois State Geological Survey. Although significant milestones of understanding of the Pleistocene have been accomplished in their work, they have encouraged the leaders of this conference to pursue further studies to develop a greater understanding of the glacial history of Illinois. During the preparation for this conference, the tour leaders received cooperation and assistance from many landowners and organizations. We want to extend our appreciation to James Hildebrand, Superintendent of Farmdale Park, Tazewell County; Dillard Royer; Lewistown City Council; Warren Stock; Charles Dunseth; Loren Hopwood; Daniel Roadruck and Walter Ginn, Western Materials Company, Medusa Aggregates; Jack Brown, Superintendent of Indian Point Quarry, Material Service Corpo- ration; and the Illinois State Museum. The tour leaders greatly appreciate the support from the Department of Geology, University of Illinois, for cosponsoring the conference and for assistance from the staff and graduate students. Many staff members at the Illinois State Geological Survey assisted in the conference. Clay minerals were analyzed by H. D. Glass. Grain size analyses were made by Rebecca Bianchini and Holly Radis. Radiocarbon age determinations were made by Jack Liu. Inez Kettles assisted in the carbonate mineral analyses. Assisting in conducting the field conference were R. C. Berg, C. S. Hunt, M. M. Killey, J. T. Wickham, S. S. Wickham, P. C. Reed, J. M. Masters, T. M. Johnson, D. E. Lindorff, H. J. H. Harris, P. V. Heinrich, G. M. Fleeger, and W. H. Johnson. Interpretations were discussed with H. B. Willman, H. D. Glass, J. P. Kempton, J. T. Wickham, and W. H. Johnson, who made many valuable comments. Editing, drafting, and design work was done by Joyce Tikalsky and Nancy Stark. Dorothy Huffman prepared the registration materials and Debra Kaufman typed the manuscript. INTRODUCTION The purpose of this field conference is (1) to reexamine the classic Farm Creek Section, which has been studied by geologists for nearly 90 years and has been used by many workers as a type or reference section for several rock-, time-, and soi 1 -stratigraphic classifications of the Quaternary, (2) to ex- amine details of the development of the Sangamon Soil under varying environ- mental conditions in its type region, (3) to consider some details of strati- graphic and compositional variations in the Wisconsinan loesses and their re- lation to Wisconsinan glaciation in Illinois, and (4) to outline some new ideas on the stratigraphy and duration of the Illinoian Stage in Illinois. The papers and interpretations of geologic sections in this guidebook repre- sent a report on the status and development of these continuing investiga- tions. The Peoria-Springfield, Illinois, region has been trodden by many well- known Quaternary geologists during the last century. Worthen, Leverett, Leighton, MacClintock, Horberg, Willman, and Frye, to name but a few, used sections in the region to develop concepts of Quaternary stratigraphy, yet much remains to be done. Recently developed ideas on basic classification of the Quaternary, on correlation of climatic changes with the marine record, on soil development in the geologic past, and on interpretation of proglacial loess deposits are based on studi es in this classical region and will be ex- amined during the field conference. The papers included in the guidebook contribute to an understanding of the geology of the Peoria-Springfield region. Descriptions, discussions, and analytical data from several major geologic sections in the region, some of which will be visited during the field conference, are also presented. The remainder of the guidebook is intended as a reference to guide the reader in visiting sections that are still available. No road log is provided in the guidebook. REGIONAL STRATIGRAPHY Sheets of drift from the Illinoian and Wisconsinan Stages cover the Peoria- Springfield region (fig. 1). Older drift is found in places below the Illi- noian. Statewide distribution of Quaternary deposits in Illinois has been mapped recently (Lineback, in press), and statewide stratigraphic nomenclature of the Quaternary (modified from Willman and Frye, 1970) is summarized on the inside back cover. INTRODUCTION/1 10 0 10 20 30 40 Miles 1 I I I I I I t— I— I— I— I I — I 10 0 10 20 30 40 50 Kilometers l-l l-l I I I HH M I I ^ Time-, 1 rock-, and soi -stratigraphic units used in the Peoria-Springf ield region are summarized in figure 2. Nomenclature and time-stratigraphic rela- tionships shown by figure 2 include recent tentative modifications that are discussed in the papers in this volume. Two major preglacial valleys, the Ancient Mississippi and the Teays- Mahomet, meet in Mason County between Peoria and Springfield. These valleys have been filled by repeated glacial advances during the Quaternary. Drift 2/REGIONAL STRATIGRAPHY Figure 1. Quaternary deposits of the Peoria- WISCONSINAN AND HOLOCENE Springfield region, Illinois. (Simplified from Lineback, in press. sm Surface mines—areas where Quaternary deposits and bedrock are mixed because of surface mining activity. c Cahokia Alluvium— deposits in floodplains and channels of modern rivers and streams; mostly poorly sorted sand, silt, or clay; in many places overlies well-sorted glacial outwash of the Henry Formation. pv Peyton Colluvium—narrow deposits of largely unsorted debris accumulating on and at the base of steep slopes by creep and slope wash. pi Parkland Sand— wind-blown sand, well-sorted medium- grained sand in dunes and thick sheets between dunes. gl Grayslake Peat— peat, muck, and marl; dominantly organic deposits in lake basins on floodplains. WISCONSINAN e Equality Formation— largely slack-water lakes in major valleys and tributaries. Occurs mostly as terrace rem- anents of fine-grained materials. h Henry Formation—sand and gravel, generally well sorted, glacial outwash in outwash plains, valley trains, terrace remanents of valley trains, and ice-contact deposits. pr Peoria Loess and Roxana Silt combined—wind-blown silt more than 6 meters (20 ft) thick on uplands; local lenses of fine-grained sand. Wedron Formation— mainly glacial till with some lenses and beds of sand, gravel, and silt. ws Snider Till Member— mostly gray silty clay till. wb Batestown (east) and Maiden (north) Till Members- wm gray silty till; oxidizes to olive brown.
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