Schlumberger sounding results near Twin Falls, Idaho, 1987

The U.S. Geological Survey has made 85 Schlumberger soundings near Twin Falls, Idaho since 1982. These soundings were made in support of the Water Resources Division Regional Aquifer-Systems Analysis study.  The soundings were made to estimate the thickness of the basalt, which is the main aquifer in this area.

The surveyed area is mostly in the Snake River Plain and is composed primarily of Quaternary basalt. Interflow zones of cinders and rubble Make for high porosity and high hydraulic conductivity (Whitehead and Lindholm, 1985). Tertiary aged Banbury Basalt of the Idaho Group (Covington, 1976) is exposed in the wall of the Snake River canyon and probably underlies the Quaternary basalt in the study area.

The purpose of this report is to release the observed Schlumberger sounding data. An automatic interpretation of the soundings is also given.