Abstract
We present a new geomorphic model for the intraplate eastern Tennessee seismic zone (ETSZ). Previous studies document that the Upper Tennessee drainage basin is in a transient state of adjustment to ~150 m of base level fall that occurred in the Late Miocene. Using quantitative geomorphology, we demonstrate that base level fall resulted in the erosion of ~3,500 km3 of highly erodibility rock in an ~70 km wide by ~350‐km‐long corridor in the Paleozoic fold‐thrust belt above the ETSZ. Models of modern incision rates show a NE‐SW trending swath of elevated erosion ~30 km southeast of the center of the ETSZ. Stress modeling shows that lithologically focused erosion has affected fault clamping stress on preexisting, favorably oriented faults. We argue that the lithologically controlled transient erosional response to base level fall in the Upper Tennessee basin has given rise to and is sustaining earthquake activity in the ETSZ.
Document Type
Article
Publication Date
9-28-2018
Digital Object Identifier (DOI)
https://doi.org/10.1029/2018GL079157
Related Content
The digital elevation model data and the digital geologic maps used in this study are available through the U.S. Geological Survey at earthexplorer.usgs.gov and ngmdb.usgs.gov, respectively.
Repository Citation
Gallen, Sean F. and Thigpen, J. Ryan, "Lithologic Controls on Focused Erosion and Intraplate Earthquakes in the Eastern Tennessee Seismic Zone" (2018). Earth and Environmental Sciences Faculty Publications. 13.
https://uknowledge.uky.edu/ees_facpub/13
Supporting Information S1
grl58006-sup-0002-2018gl079157-s01.mp4 (1859 kB)
Movie S1
Notes/Citation Information
Published in Geophysical Research Letters, v. 45, issue 18, p. 9569-9578.
©2018. American Geophysical Union. All Rights Reserved.
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