Stratigraphy and chronology of late Wisconsin Laurentide Ice Sheet fluctuations of the East White sublobe, central Indiana (2015)

Item Number: EXT0491
Map Scale: 1:0
Not available for purchase
Format(s) Not Available

Authors: Henry Loope
T Lowell
B Curry
William Monaghan
Marni Karaffa

The stratigraphy and chronology of Laurentide Ice Sheet (LIS) initial advance and fluctuations near its maximum late Wisconsin extent in central Indiana has received little attention in the past 20 years. Wayne’s 1963 work, Pleistocene Formations in Indiana (Indiana Geological Survey Bulletin 25), developed the stratigraphic nomenclature for Quaternary units in Indiana and provided an overview and context for radiocarbon ages associated with glacial sediments. Ansel Gooding (Earlham College) detailed the stratigraphy and chronology in southeastern Indiana and adjacent southwestern Ohio in the 1960s and 1970s. Radiocarbon ages compiled by Ned Bleuer (Indiana Geological Survey) in the 1970s and 1980s in west-central Indiana and mapping of Marion County in the 1990s provide the latest effort. Here, we compile published and unpublished radiocarbon ages (n=81) within Indiana to establish a chronologic framework and to identify spatial and temporal gaps in the existing data set to guide future work. Using this radiocarbon data set, we interpret that the LIS reached ca. 40.5 degrees north latitude (80 km north of Indianapolis) by 26.0 k cal yr BP, based on the youngest maximum ages from cutbank exposures along Wildcat Creek (Carroll County) and boreholes in Tipton and Hamilton Counties north of Indianapolis. The largest concentration of ages occur within 30 km of the late Wisconsin maximum position, and the majority of ages suggest advance to the maximum limit ca. 24–23 k cal yr BP, in agreement with advance to the maximum limit in southwestern Ohio and east-central Illinois. However, two newer sites—Flat Rock and Plainfield—suggest a younger advance (22 k cal yr BP) to the maximum limit, as well as a younger readvance ca. 19.6 k cal yr BP. This potential readvance is not well understood at this time and requires further investigation. One obstacle in the interpretation of this data set is that a majority of the radiocarbon ages are over 30 years old (pre-AMS with large errors) and the accurate location and stratigraphic position of collected organic material is not known at all sites. A reinvestigation of these sites along with additional outcrop and borehole data from central Indiana will help resolve stratigraphic and chronologic questions.



Loope, H. M., Lowell, T. V., Curry, B. B., Monaghan, G. W., and Karaffa, M. D., 2015, Stratigraphy and chronology of late Wisconsin Laurentide Ice Sheet fluctuations of the East White sublobe, central Indiana [abst.]: 49th Annual Meeting of the Geological Society of America, North Central Section, Madison, Wisc., May 19-20, 2015.


You may also like:

Keywords: Laurentide Ice Sheet, glacial geology, glacial history, Pleistocene

This item is no longer available. Please contact the Indiana Geological and Water Survey Publication Sales Office for more information. Many IGWS publications are available through local libraries.


Publication Sales Office
Indiana Geological Survey
611 North Walnut Grove
Bloomington, IN 47405-2208
(812) 855-7636 office phone
(812) 855-2862 office fax
IGSINFO@indiana.edu

Generating Your PDF

Your session for the Indiana Geological and Water Survey will expire in 30 minutes. Please refresh your broswer or click here to restart your session timer.