SCHLUMBERGER SOUNDING RESULTS OVER THE NEWBERRY VOLCANO AREA, OREGON.

Robert J. Bisdorf

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USGS · 70013262

SCHLUMBERGER SOUNDING RESULTS OVER THE NEWBERRY VOLCANO AREA, OREGON.

Robert J. Bisdorf

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Abstract

Schlumberger soundings were made in the Newberry volcano area of Oregon to categorize the electrical properties of possible Cascade geothermal systems. An east-west geoelectric cross section constructed from the interpreted soundings shows a low-resistivity zone in the caldera, that corresponds to the increase in thermal gradient observed in a U. S. Geological Survey test well. Another low resistivity zone about 600 m deep is present just to the west of the caldera boundary. A north-south geoelectric cross section shows the configuration of the western low-resistivity zone. Maps of interpreted resistivity at depths of 750 and 1000 m show that the main low resistivity area west of the caldera has two tongues, one oriented easterly and the other oriented southerly.

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Robert J. Bisdorf. 1985. SCHLUMBERGER SOUNDING RESULTS OVER THE NEWBERRY VOLCANO AREA, OREGON.. https://pubs.usgs.gov/publication/70013262

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