12 D3. North American Rifts, Faults, and Tectonic Activity

Monday, 10 March 2025
1:30 PM - 5:30 PM
114

THE REELFOOT RIFT - PAST, PRESENT, AND FUTURE

Paper number: 12-1
Program: Technical Sessions
Time: 1:30 PM – 1:50 PM

Authors

Abstract

The Reelfoot rift extends from southern Arkansas into southwestern Kentucky and is the southern portion of the Reelfoot rift-Rough Creek graben-Rome trough fault system that experienced faulting during three periods between 760 Ma and 530 Ma as the southeastern portion of the United States attempted to rip from North America. The NE-trending Reelfoot rift cut across pre-existing NW-trending faults, which resulted in the formation of sub-basins within the rift that may have affected late Proterozoic and Cambrian deposition. Most, if not all, of these faults have been reactivated through time. End of Paleozoic Appalachian-Ouachita compression resulted in the uplift of the Axial fault system down the middle of the Reelfoot rift and the entire rift was part of a larger late Cretaceous thermal uplift caused by the passage of the United States over the Bermuda hotspot. Erosion of the uplift and subsequent thermal subsidence upon passing of the Reelfoot rift region off the hotspot resulted in the formation of the Mississippi embayment. Cenozoic compression has reactivated Reelfoot rift faults that continues into the Holocene. The great New Madrid earthquakes of 1811-1812 occurred on a small portion of the Reelfoot rift and this fault reactivation appears to be related to major Pleistocene erosion within the Mississippi River valley above three Reelfoot rift faults. The question remains as to the possible repeat of these great earthquakes and or the possibility of renewed activity on the remaining Reelfoot rift faults.

Geological Society of America Abstracts with Programs. Vol. 57, No. 1

doi: 10.1130/abs/2025SC-407247

© Copyright 2025 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.