HR: 17:15h
AN: GP12B-06    [PDF]
TI: Deep MT Sounding Across the Yellowstone-Snake River Hotspot Track
AU: * deGroot-Hedlin, C D
EM: chedlin@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, San Diego, CA 92093-0225 United States
AU: Steven, C C
EM: sconstable@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, San Diego, CA 92093-0225 United States
AU: Booker, J R
EM: booker@ess.washington,edu
AF: University of Washington, Dept Earth & Space Sciences, Seattle, WA 98195 United States
AU: Terzi, L
EM: lterzi@igpp.ucsd.edu
AF: University of Milan, 123, Milan, 12345 Italy
AU: Weitemeyer, K
EM: kandrea@igpp.ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, San Diego, CA 92093-0225 United States
AB: The Snake River Plain (SRP) in Idaho marks the path of an active hotspot with a terminus under Yellowstone National Park in Wyoming. The trace of the hotspot is marked by a series of volcanic caldera ranging in age from 16 million years in southeastern Oregon and northern Nevada to several thousand years to the northeast. The motion of the North American plate over this feature has resulted in an apparent northeastward progression of the focus of the volcanism. In previous studies, a narrow, deep, low velocity zone below the SRP has been imaged using teleseismic P-wave residuals. This past summer, we collected magnetotelluric (MT) data along a transect across the SRP to map the conductivity structure of this region. The objective is to detect features associated with the Yellowstone hotspot, and ultimately, to place limits on the temperature and melt fraction of these features. To this end, we collected long period electrical and magnetic data at 19 sites using the NIMS equipment from the EMSOC instrument pool, and broadband field data at 2 sites using SIO's MT equipment. The sites were located along a northwest-southeast line stretching from near Challis to the southeast corner of Idaho, at an average spacing of 20 km. The results of our first summer of fieldwork are presented here.
DE: 0925 Magnetic and electrical methods
DE: 1515 Geomagnetic induction
DE: 3914 Electrical properties
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2003 Fall Meeting