Document Type
Honors Project
Publication Date
2023
Abstract
The Late Cambrian Elk Mound Group consists of three supermature sandstone formations deposited in and on the shores of a shallow, tropical sea: the Mount Simon, Eau Claire, and Wonewoc formations, in ascending order. Workers have used detrital zircon (DZ) U-Pb analysis to constrain the sources of the sand grains and build a regional provenance model. This study considers new samples from the Mount Simon Sandstone in the context of previous DZ studies in Wisconsin and Illinois. The samples reveal a transition from Mesoproterozoic source provinces towards Late Archean source provinces over time, which is understood to represent a shift from sediments derived from the more local Wolf River Batholith and Penokean orogenies to sediments derived from the more distal Superior Province. Such a shift likely reflects rising sea levels, which drowned local provinces and prevented their erosion while leaving more distal provinces high and dry. Along with the DZ data, paleocurrent indicators derived from optical borehole image logs from wells across central Wisconsin add to the regional provenance picture with evidence of currents predominantly flowing toward the west and southwest, giving some indication of the more immediate source and final transport of these sediments.
Level of Honors
summa cum laude
Department
Geosciences
Advisor
Marcia Bjornerud
Recommended Citation
Bojdak-Yates, Itai S., "A Revised Provenance Model for the Elk Mound Group in South-Central Wisconsin Based on Detrital Zircon Analysis" (2023). Lawrence University Honors Projects. 176.
https://lux.lawrence.edu/luhp/176