Drilling, construction, geophysical data, and lithologic log for borehole USGS 151

In 2020, the U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy (DOE) for Naval Reactors Laboratory Field Office or Naval Reactors Facility (NRF), drilled and constructed borehole USGS 151 (433846112540701) for stratigraphic framework analyses at the Idaho National Laboratory (INL) near the NRF, located in southeastern Idaho. Borehole USGS 151 was continuously cored from approximately 48 to 1,070 feet below land surface (BLS) and rotary drilled from approximately 1,070 to 1,720 feet BLS. Core drilling was discontinued after 1,070 feet BLS and changed over to straight rotary drilling due to funding constraints and deadlines. The USGS collected select geophysical data, daily drilling notes, and prepared detailed core descriptions for core collected to 1,070 ft BLS, which are included as part of this data release. The USGS Research Drilling Program (RDP) performed the core drilling operations and well construction between June 4, 2020 to September 21, 2020; additionally, the USGS RDP collected geophysical data, single caliper log, that was collected on August 15, 2020. The USGS INL Project Office collected multiple geophysical logs on September 15, 2020.

Select geophysical data include natural gamma, caliper, neutron, and gamma-gamma density logs which were examined synergistically with available core material to identify contacts between basalt flows and location and thickness of sediment layers. Additionally, a gyroscopic deviation survey was performed and analyzed to reflect the projected well bore path. Geophysical data were collected using Century™ multi-parameter logging probes and select logs are displayed in well log figures. Geophysical data shown in figure displays include the natural gamma and neutron probe (9055C), caliper probe (9065A), gamma-gamma density probe (0024C), and gyroscopic deviation probe (9095C). With the exception of the caliper log, all geophysical data were collected through drill pipe after reaching total depth. Geophysical log data not represented in figure displays can be obtained by downloading attached LAS files.

Drill core was taken to the USGS Lithologic Core Storage Library for storage and permanent archive located at Central Facilities Area on the INL. Drill core was photographed and described using standardized methods (Johnson and others, 2005). These standardized methods make use of commercially available software that include using a procedure developed by the USGS INL Project Office. The standardized method maximizes description and minimizes interpretation.