Landscape evolution in south-central Minnesota and the role of geomorphic history on modern erosional processes

Karen B Gran, Patrick Belmont, Stephanie S. Day, Noah Finnegan, Carrie Jennings, J. Wesley Lauer, Peter R. Wilcock

Research output: Contribution to journalArticlepeer-review

23 Scopus citations

Abstract

The Minnesota River Valley was carved during catastrophic drainage of glacial Lake Agassiz at the end of the late Pleistocene. The ensuing base-level drop on tributaries created knickpoints that excavated deep valleys as they migrated upstream. A sediment budget compiled in one of these tributaries, the Le Sueur River, shows that these deep valleys are now the primary source of sediment to the Minnesota River. To compare modern sediment loads with pre-European settlement erosion rates, we analyzed incision history using fluvial terrace ages to constrain a valley incision model. Results indicate that even thoughthe dominant sediment sources are derived from natural sources (bluffs, ravines, and streambanks), erosion rates have increased substantially, due in part to pervasive changes in watershed hydrology.

Original languageEnglish (US)
Pages (from-to)7-9
Number of pages3
JournalGSA Today
Volume21
Issue number9
DOIs
StatePublished - Sep 1 2011

Fingerprint Dive into the research topics of 'Landscape evolution in south-central Minnesota and the role of geomorphic history on modern erosional processes'. Together they form a unique fingerprint.

Cite this