In-person Lecture: The Upper Mississippi Valley: Proglacial Origins to Modern...

Presenter: Andrew Wickert, Ph.D., Associate Professor, Department of Earth and Environmental Sciences, University of Minnesota

Link to Presenter: https://cse.umn.edu/esci/andrew-wickert

2nd Link to Presenter: https://www.linkedin.com/in/andywickert

Full Lecture Title: The Upper Mississippi Valley: Proglacial Origins to Modern Evolution

Summary: The upper Mississippi River valley formed and integrated when early Pleistocene glaciations dammed north-flowing rivers, causing them to overtop and incise ancient drainage divides to the south. These steeplands evolved in the ca. 1–2 million years that followed, growing a network of tributaries that dissected the surrounding plateaus. When we step forward to the Wisconsin ice-sheet advance, ca. 30,000 years ago, sediments sourced from glacial erosion filled the Mississippi valley, forming high floodplains. During deglaciation, proglacial lakes trapped coarse sediments, and sediment-starved meltwater entrained and incised through these proglacial river deposits, leaving them high above the modern Mississippi. Both Indigenous and Euro-American cities were built on the resultant high terrace surfaces. The arrival of Euro-American agriculture increased erosion 10x beyond background rates, filling valleys with sediments. Looking to the future of climate and land-use change, we hope to use these stories from the upper Mississippi valley to benchmark process-based models and better predict how today's actions shape tomorrow's landscapes.

Biography: Prof. Andrew Wickert conducts field investigations, develops physics-based theory, designs and deploys instrumentation, and builds numerical models to understand and forecast how rivers and landscapes change.

General Info: GSM lectures/seminars with slide show presentations are free and open to the public. They are presented by leading professionals in their fields and are aimed at learners from high school to adult. A question-and-answer session follows each seminar. In-person lectures require no registration; just show up a few minutes early on the evening of the lecture. These lectures are eligible for 1 hour of Continuing Education Unit (CEU) credit.

Except as noted, in-person lectures during the fall 2025 semester are Mondays at 7:00 PM CT on the University of Minnesota campus, Keller Hall, Room 3-230.

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