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Carol A Finn

Research Geophysicist

Geology, Geophysics, and Geochemistry Science Center

Office Phone: 303-236-1345
Fax: 303-236-1425
ORCID: 0000-0002-6178-0405

Supervisor: Paul A Bedrosian
Hydrothermally altered rocks, particularly if water saturated, can weaken stratovolcanoes, thereby increasing the potential for catastrophic sector collapses that can lead to far-traveled, destructive debris flows, which are the largest volcanic hazards for Mount Adams and Mount Baker. Evaluating the hazards associated with such alteration is difficult because much of the alteration is obscured by ice and its depth extent is unknown. Intense hydrothermal alteration significantly reduces the resistivity and magnetization of volcanic rock and therefore hydrothermally altered rocks are identified with helicopter electromagnetic and magnetic measurements at Mount Baker and Mount Adams. High resolution magnetic and electromagnetic...
Note: There is an updated version of this data release, available here: A helicopter-borne electromagnetic/magnetic survey was flown over the Stillwater area, southwest Montana from May 5 to May 16, 2000. The survey was conducted over the Stillwater Igneous Complex, a Precambrian layered mafic-ultramafic intrusion which is characterized by igneous layering. Electromagnetic data were acquired using DIGHEM helicopter-borne electromagnetic system. Magnetic data were collected with optically pumped Cesium Vapor Geometrics G822 magnetometer. Sensor elevation above ground was measured with Honeywell/Sperry AA220 radar. The nominal elevation of the sensor was 60 meters. Survey coverage...
Gravity data were collected during three separate campaigns during July of 2013, August and September of 2014, and September and October of 2020 at 168 sites on and around the Stillwater layered mafic complex in southern Montana. Measurements were taken with Lacoste & Romberg G-64, G-550, and G-161 gravimeters and reduced to obtain the complete Bouguer anomaly, with reference ties to absolute base stations at U.S. Post Offices in Spokane, Washington (2014), Billings (2013-2014) and Livingston (2020), Montana. This data release includes principal facts for 168 new gravity stations and shapefiles with field locations.
Airborne electromagnetic (AEM) and magnetic survey data were collected during November and December 2016 along 4,212 line-kilometers over Yellowstone National Park, Wyoming. The survey was conducted as part of a study of the subsurface geologic structure and geothermal and groundwater resources of Yellowstone National Park. The survey was designed to image the subsurface plumbing of Yellowstone's myriad thermal features by constraining the geometry of the major hydrostratigraphic contacts and mapping regional-scale geologic structures. Data were acquired by SkyTEM ApS with the SkyTEM 312M time-domain helicopter-borne electromagnetic system together with a Geometrics G822A cesium vapor magnetometer. The survey was...
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: GGGSC, Geology, Geophysics, and Geochemistry Science Center, Geophysics, Grand Canyon of the Yellowstone River, Hot Spring Basin Group, All tags...
Airborne electromagnetic (AEM) and magnetic survey data were collected during June 2012 along 556 line-kilometers over Iliamna Volcano, Alaska. These data were collected in support of alteration and volcano flank instability mapping as part of the U.S. Geological Survey (USGS) Volcano Hazards Program. Data were acquired by SkyTEM Survey ApS SkyTEM304 system with the Soloy Helicopters Eurocopter Astar 350 B3 and Bell 407 dual-moment, time-domain helicopter-borne electromagnetic system together with a Geometrics G822A cesium vapor magnetometer with Kroum KMAG4 counter. The survey was flown at a nominal flight height of 30 meters (m) above terrain along block-style lines with a nominal spacing of 250 m. The survey...
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