In situ bulk density estimates from borehole gravity data in limestones of the Madison Group, test well No. 2, Custer County, Montana
Explore the source record for details and available documents.
Geology topics
Publications and source records attributed to Bruce A. Kososki.
Explore the source record for details and available documents.
In 1975 the U.S. Geological Survey, in cooperation with the Old West Regional Commission, prepared a plan of study (U.S. Geological Survey, 1975) for evaluating the water-supply potential of limestone of the Madison Group and associated rocks. To obtain better subsurface hydrologic and geologic information it was recognized that Madison Group test wells would have to be drilled. This report tabulates the results of in situ bulk density and porosity determinations from borehole gravity data obtained in the first of these wells, test well no. 1.
In August of 1976, borehole gravity surveys were conducted by the U.S. Geological Survey at the Nevada Test Site in the Ue10j, Ue7ns, and Ue5n test wells. The work was done in cooperation with the Lawrence Livermore Laboratory. The U.S. Geological Survey-LaCoste and Romberg borehole gravity meter was used in the logging program (McCulloh and others, 1967a; McCulloh and others, 1967b). The primary objective of this work was to obtain data for the determination of in situ formation densities utilizing an instrument not significantly affected by casing, borehole rugosity, or other near-borehole conditions. A secondary objective was to obtain duplicate data, by reoccupying subsurface stations, so that the precision and repeatability of borehole gravity data could be studied.
Since 1972 the U.S. Geological Survey has been conducting a series of field evaluation studies in southeastern New Mexico for the Waste Management Division of the Department of Energy (formerly U.S. Energy Research and Development Administration). On the basis of these studies, a tentative site for a nuclear waste repository/disposal facility has been selected near the center of the Los Medafios area in Eddy and Lea Counties, New Mexico (Fig. 1). The proposed host rock for the emplacement of nuclear waste at the potential repository site consists of the bedded evaporite deposits of the Salado Formation. Numerous test holes have been drilled in the Los Medafios area to determine geologic conditions and to obtain geophysical data and rock samples for additional site-evaluation studies. This report tabulates borehole gravity data acquired in one of these test holes, ERDA No. 9, and summarizes the geology of the consolidated rock formations in which gravity observations were made.
During field studies conducted in October 1977 and March 1978, borehole gravity surveys were completed by the U.S. Geological Survey at the Nevada Test Site in test well Ue19z, exploratory drill hole PH-1, and water well 5a. The U.S. Geological Survey-LaCoste and Romberg-1/ borehole gravity meter (McCulloh and others, 1967a; McCulloh and others, 1967b) was used in the logging program. The primary objective of this work was to obtain data for the determination of accurate in situ formation densities utilizing an instrument not significantly affected by casing, borehole rugosity, or other near-borehole conditions. This report provides a brief summary of the geology of the rock formations penetrated by drill holes Ue 19z, PH-1, and water well 5a, and tabulates the subsurface gravity data obtained in these, wells. Reduced sections of the gamma-ray logs run in PM-1 and 5a are also included.