Geomorphology and Chronology of Sand Stringer Deposition Beyond the Ice Margin: Southeastern Minnesota and Western Wisconsin, USA

Author

Richard J. Mataitis, Minnesota State University, Mankato

Abstract

The purpose of this Master’s thesis is to investigate linear, aeolian deposits termed “sand stringers” located within western Wisconsin and southeastern Minnesota. Previous research has investigated their spatial distribution, and to a minor extent, their composition and absolute age. However, further sedimentological and absolute age data are needed from a greater distribution of sand stringers to understand their formation and depositional chronology. To build on previous research we 1) remotely mapped the spatial distribution and orientation of sand stringers in western Wisconsin and southeastern Minnesota, 2) collected absolute age data using optically stimulated luminescence (OSL) from four stringers in western Wisconsin, 3) collected ground penetrating radar (GPR) data from a single stringer in Eau Claire County, and 4) described soil auger profiles from the Eau Claire County sand stringer (ECC). The remote mapping identified 246 potential stringers, with 91% orientated WNW-ESE. The sand stringer distribution is likely controlled by fetch and proximity to sediment sources, and orientation and previous studies suggest WNW winds formed sand stringers in our study area. OSL ages ranged from ~12.9 ka to ~8.9 ka and indicate deposition roughly corresponding to the Pleistocene-Holocene Transition. GPR surveys revealed sub-parallel and slightly undulating stratigraphy similar to that of sand sheets. Soil augering revealed two distinct units consisting of a lower coarse sand unit interpreted as glacial outwash, a middle unit of fine to medium sand interpreted as aeolian sand, and unknown upper material composed of fine sand and silt.

Advisor

Phillip Larson

Committee Member

Mark Bowen

Committee Member

Garry Running

Date of Degree

2020

Language

english

Document Type

Thesis

Degree

Master of Science (MS)

College

Social and Behavioral Sciences

Recommended Citation

Mataitis, R. J. (2020). Geomorphology and chronology of sand stringer deposition beyond the ice margin: Southeastern Minnesota and western Wisconsin, USA [Master’s thesis, Minnesota State University, Mankato]. Cornerstone: A Collection of Scholarly and Creative Works for Minnesota State University, Mankato. https://cornerstone.lib.mnsu.edu/etds/1056

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.