T147 Dynamics of Huge Floods

Tuesday, 12 October 2021
8:00 AM - 12:00 PM
Portland Ballroom 254 (Hybrid Room)

AGE OF LAST GLACIAL MEGAFLOODS IN MOSES COULEE AND GRAND COULEE

Paper number: T147-3
Program: Technical Sessions
Time: 8:20 AM – 8:40 AM

Authors

Abstract

It is unclear how and when Missoula Floods entered Moses Coulee, one of the great canyons of the Channeled Scabland.

Here we present new geochronology that helps to tie Moses Coulee into the regional flood history.

Four ice-rafted boulders in Moses Coulee have exposure ages that are older than flood-transported boulders below Grand Coulee. These ages are consistent with a flood-routing history in which Moses Coulee flooded before Grand Coulee during the last glaciation, a sequence previously inferred from megaflood deposits at the mouth of Moses Coulee.

Geological Society of America Abstracts with Programs. Vol. 53, No. 6

doi: 10.1130/abs/2021AM-370230

© Copyright 2021 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.