Magnetotelluric and TEM Data from the Umatilla Indian Reservation Geothermal Resources Assessment: Phase 2, 2020

This data set consists of 19 wideband magnetotelluric (MT) and 23 transient electromagnetic (TEM) soundings collected by the U.S. Geological Survey in June 2020 as part of the Umatilla Indian Reservation Geothermal Resources Assessment: Phase 2 project. Each MT station had 4 components, 2 orthogonal magnetic induction coils and 2 horizontal orthogonal electric dipoles. Data were collected for an average of 18 hours on a repeating schedule of alternating sampling rates of 256 samples/second for 5 hours and 50 minutes and 4096 samples/second for 10 minutes. The schedules were set such that each station was recording the same schedule to allow for remote reference processing. Data were processed with a bounded-influence robust remote reference processing scheme (BIRRP v5.2.1, Chave and Thomson, 2004). Data quality were generally poor due to episodic spikes in the electromagnetic fields likely caused by the power grid. TEM data were collected in 100 x 100 m loops or 40 x 40 m loops along 4 profiles in areas of interest for geothermal potential. Files included in this publication include measured electric- and magnetic-field time series for MT data, MT transfer functions, TEM soundings, and 1-D resistivity models from the TEM soundings. The structure of this data release includes a child page for each MT station and a child page for the TEM data.  Shapefiles for the locations are provided on the parent page.