Boreholes in Oasis Valley were geophysically logged to define the lithology, stratigraphy, and geohydrologic characteristics of the rock units penetrated during drilling. Geophysical logs were run in an open-hole filled with drilling fluid if the hole was mud-rotary drilled or water if the hole was partly or totally drilled with an air hammer. The boreholes were allowed to equilibrate for at least 3 hours after drilling completion before logging started; deep boreholes (greater than 200 ft) were allowed to set for at least 12 hours. The types of geophysical logs collected and their applications are listed in table 3. A typical suite of logs for each borehole consisted of a caliper log, natural-gamma log, conductivity log, resistivity log, resistance log, and spontaneous-potential log. Additionally, some of the boreholes have the following logs: short- and long-normal resistivity, lateral resistivity, acoustic velocity, fluid temperature, fluid resistivity, fluid specific conductance, acoustic televiewer, and heat-pulse flowmeter. A borehole video log was run in well ER-OV-06a. The set of logs obtained from each borehole is presented in figures 6-16 in the supplementary data section. Logs of spontaneous potential in wells ER-OV-02, -03a, -06a, and -06a2 recorded interference from a poorly grounded generator and, therefore, are not shown.
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