DMS Products: EMC-SRPY-MT Regional 3-D electrical conductivity model of Snake River Plain / Yellowstone, USA based on magnetotelluric data

Summary

A 3-D regional electrical conductivity model of the crust and upper mantle beneath the Yellowstone/Snake River Plain volcanic province (Idaho and Wyoming, United States) based on magnetotelluric data, Kelbert, Egbert, and deGroot-Hedlin (2012) .

Description

Name SRPY-MT
Title Regional 3-D electrical conductivity model of Snake River Plain / Yellowstone, USA based on magnetotelluric data
Type 3-D Regional Electrical Conductivity Model
Sub Type Long-period Magnetotelluric
Units Siemens/meter
Year 2012
 
Short Description   Kelbert, Egbert, and deGroot-Hedlin (2012) : This study uses high-quality electromagnetic data obtained through the EarthScope USArray project to obtain detailed three-dimensional images of electrical resistivity / conductivity in the crust and upper mantle beneath the Yellowstone/Snake River Plain volcanic province (Idaho and Wyoming, United States).
The lowest resistivities in the area can only plausibly be explained by partial melt and/or fluids, providing valuable new information about the distribution of these phases deep within the Earth beneath the volcanic system. Unexpectedly, in light of the mantle plume models often used to explain Yellowstone volcanism, the electromagnetic data imply that there is no interconnected melt in the lower crust and uppermost mantle directly beneath the modern Yellowstone caldera. Instead, low resistivities consistent with 1-3% melt in the uppermost mantle (depths of 40-80 km) extend at least 200 km southwest of Yellowstone. Shallower areas of reduced resistivity extend upward into the mid-crust around the edges of the seemingly impermeable Snake River Plain province, including beneath Yellowstone.
We suggest that the elevated temperatures beneath the active volcanic center have resulted in greater permeability, allowing magma to ascend to shallower depths and pool in the crust. Little melt is entering the system from below at present, perhaps due to intermittency of supply.
Authors:  
A. Kelbert
College of Earth, Ocean and Atmospheric Sciences
Oregon State University
Corvallis, Oregon 97331, USA
G. D. Egbert
College of Earth, Ocean and Atmospheric Sciences
Oregon State University
Corvallis, Oregon 97331, USA
C. deGroot-Hedlin
Scripps Institution of Oceanography
University of California
San Diego, La Jolla, California 92037, USA
 
Previous Model N/A
Reference Model N/A
Prior Model 200 Ohm*m halfspace
Inversion Software Modular System for Electromagnetic Inversion, Egbert and Kelbert (2012)
Model Download SRPY-MT.nc (metadata ) is the netCDF binary for the above regional 3-D electrical conductivity model .
Model Homepage N/A
Depth Coverage 10 – 250 km, most reliable to ~100 km depth
Areal Coverage atitude: 41.0° to 46.5°, longitude: -119.0° to -107.0°
 
Data Set Description Frequency domain long-period (10 to 1e4 secs) magnetotelluric (MT) data from 91 EarthScope MT sites, covering much of Idaho and Wyoming, southern Montana, eastern Oregon and northern Nevada, together with 32 sites from an earlier MT survey collected by C. deGroot-Hedlin in two denser profiles along and across the eastern SRP.

The isosurface of 40 Ohm*m and below resistivities

Figure shows 3-D views of the magmatic system beneath the Snake River Plain/Yellowstone volcanic province, as inferred from magnetotelluric data. The isosurface of 40 Ohm*m and below resistivities; data locations are plotted on top. Yellowstone is indicated with an open circle. Note the conductive pathway to the Yellowstone caldera from beneath the eastern Snake River Plain.

Three cross-sections that show log10 conductivities in the same area

Figure shows 3-D views of the magmatic system beneath the Snake River Plain/Yellowstone volcanic province, as inferred from magnetotelluric data. Three cross-sections that show log10 conductivities (S/m) in the same area.

Citation

  • Kelbert A., Egbert G.D., deGroot-Hedlin C. 2012. “Crust and upper mantle electrical conductivity beneath the Yellowstone Hotspot Track” Geology, v. 40, p. 447-450, doi:10.1130/G32655.1.
  • Trabant, C., A. R. Hutko, M. Bahavar, R. Karstens, T. Ahern and R. Aster (2012), Data products at the IRIS DMC: stepping-stones for research and other application, Seismological Research Letters, 83(6), 846:854. doi: 10.1785/0220 120032 .

References

  • Egbert G.D. and A. Kelbert. 2012. “Computational recipes for electromagnetic inverse problems.” Geophysical Journal International, 189:251-267, DOI: 10.1111/j.1365-246X.2011.05347.x.

Credits

  • A. Kelbert, G.D. Egbert, and C. deGroot-Hedlin

DOI

There is no DOI currently assigned for this product.

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