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Geophysical logs and hydrologic data for eight wells in the Coyote Spring Valley area, Clark and Lincoln counties, Nevada

Geophysical logs, drilling operations, pump-test data, and water quality determinations are presented for eight wells in the Coyote Spring Valley area of southeastern Nevada. The wells are in an area where thick units of Paleozoic carbonate rock are overlain by Tertiary semiconsolidated basin-fill deposits and Quaternary alluvial deposits. Data collected by the U.S. Geological Survey were augmented with data from previous investigations; however, complete sets of logs and other data are not available for all eight wells. Geophysical data presented included natural-gamma, neutron, gamma-gamma density, caliper, temperature, acoustic, single-point resistance, long- and short-natural resistivity, and spontaneous-potential logs. Drilling penetration rates, lithologic columns, and well construction are also summarized and presented. Measurements of drawdown and recovery during and after constant-discharge pumping periods are also included. Also presented are results of chemical and physical analyses for major-ion chemistry, trace constituents, stable and radioactive isotopes, temperature, pH, specific conductance, and dissolved oxygen. (USGS)

Open-File Report↗

Drilling, construction, geophysical log data, and lithologic log for boreholes USGS 142 and USGS 142A, Idaho National Laboratory, Idaho

Starting in 2014, the U.S. Geological Survey in cooperation with the U.S. Department of Energy, drilled and constructed boreholes USGS 142 and USGS 142A for stratigraphic framework analyses and long-term groundwater monitoring of the eastern Snake River Plain aquifer at the Idaho National Laboratory in southeast Idaho. Borehole USGS 142 initially was cored to collect rock and sediment core, then re-drilled to complete construction as a screened water-level monitoring well. Borehole USGS 142A was drilled and constructed as a monitoring well after construction problems with borehole USGS 142 prevented access to upper 100 feet (ft) of the aquifer. Boreholes USGS 142 and USGS 142A are separated by about 30 ft and have similar geology and hydrologic characteristics. Groundwater was first measured near 530 feet below land surface (ft BLS) at both borehole locations. Water levels measured through piezometers, separated by almost 1,200 ft, in borehole USGS 142 indicate upward hydraulic gradients at this location. Following construction and data collection, screened water-level access lines were placed in boreholes USGS 142 and USGS 142A to allow for recurring water level measurements. Borehole USGS 142 was cored continuously, starting at the first basalt contact (about 4.9 ft BLS) to a depth of 1,880 ft BLS. Excluding surface sediment, recovery of basalt, rhyolite, and sediment core at borehole USGS 142 was approximately 89 percent or 1,666 ft of total core recovered. Based on visual inspection of core and geophysical data, material examined from 4.9 to 1,880 ft BLS in borehole USGS 142 consists of approximately 45 basalt flows, 16 significant sediment and (or) sedimentary rock layers, and rhyolite welded tuff. Rhyolite was encountered at approximately 1,396 ft BLS. Sediment layers comprise a large percentage of the borehole between 739 and 1,396 ft BLS with grain sizes ranging from clay and silt to cobble size. Sedimentary rock layers had calcite cement. Basalt flows ranged in thickness from about 2 to 100 ft and varied from highly fractured to dense, and ranged from massive to diktytaxitic to scoriaceous, in texture. Geophysical logs were collected on completion of drilling at boreholes USGS 142 and USGS 142A. Geophysical logs were examined with available core material to describe basalt, sediment and sedimentary rock layers, and rhyolite. Natural gamma logs were used to confirm sediment layer thickness and location; neutron logs were used to examine basalt flow units and changes in hydrogen content; gamma-gamma density logs were used to describe general changes in rock properties; and temperature logs were used to understand hydraulic gradients for deeper sections of borehole USGS 142. Gyroscopic deviation was measured to record deviation from true vertical at all depths in boreholes USGS 142 and USGS 142A.

Idaho↗

Surface geophysics and porewater evaluation at the Lower Darby Creek Area Superfund Site, Philadelphia, Pennsylvania, 2013

In cooperation with the U.S. Environmental Protection Agency (EPA), Region 3, the U.S. Geological Survey (USGS) is participating in an ongoing study to aid in the identification of subsurface heterogeneities that may act as preferential pathways for contaminant transport in and around the Lower Darby Creek Area (LDCA) Superfund Site, Philadelphia Pa. Lower Darby Creek, which flows into the Delaware River, borders the western part of the former landfill site. In 2013, the USGS conducted surface geophysics measurements and stream porewater sampling to provide additional data for EPA’s site characterization. This report contains data collected from field measurements of direct current (DC) resistivity, frequency-domain electromagnetic (FDEM) surveys, and stream porewater specific conductance (SC).

Pennsylvania↗

Topographic and Hydrographic GIS Datasets for the Afghanistan Geological Survey and U.S. Geological Survey 2014 Mineral Areas of Interest

Mineral extraction and associated industries play an important role in the Afghan economy, particularly in the “transitional era” of declining foreign aid and withdrawal of foreign troops post 2014. In addition to providing a substantial source of government revenue, other potential benefits of natural resource development include boosted exports, employment opportunities, and strengthened industrialization (Joya, 2012). Continued exploration and investment in these industries has resulted in large economic improvements since 2007, when this series of studies was initiated. At that time, the “Preliminary Non-Fuel Mineral Resource Assessment of Afghanistan” was completed by members of the U.S. Geological Survey and Afghanistan Geological Survey (Peters and others, 2007). The assessment published a series of country-wide datasets, including a digital elevation model (DEM), elevation contours, hydrography, transportation routes, geophysics, and cultural datasets (Peters and others, 2007). It also delineated 20 mineralized areas for further study using a geologic-based methodology. A second data product, “Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan,” was released by Peters and others in 2011. This work highlighted geologic, geohydrologic, and hyperspectral studies that were carried out in specific Areas of Interest (AOIs) to assess the location and characteristics of mineral resources. Also included in the 2011 publication is a collection of appendixes and inventories of Geographic Information System (GIS) datasets for each of the 24 identified AOIs. A third data product was released in 2013 (Casey and Chirico, 2013), publishing datasets for five different AOIs, two subareas, and one AOI extension. Each dataset contains vector shapefiles of the AOI boundary, streams, roads, and contours at 25-, 50-, and 100-meter (m) intervals, as well as raster files of the AOI’s DEM and hillshade. This work represents the fourth installment of the series, and publishes a dataset of eight new AOIs and one subarea within Afghanistan. These areas include Dasht-e-Nawar, Farah, North Ghazni, South Ghazni, Chakhansur, Godzareh East, Godzareh West, and Namaksar-e-Herat AOIs and the Central Bamyan subarea of the South Bamyan AOI (datasets for South Bamyan were published previously in Casey and Chirico, 2013). For each AOI and subarea, this dataset collection consists of the areal extent boundaries, elevation contours at 25-, 50-, and 100-m intervals, and an enhanced DEM. Hydrographic datasets covering the extent of four AOIs and one subarea are also included in the collection. The resulting raster and vector layers are intended for use by government agencies, developmental organizations, and private companies in Afghanistan to support mineral assessments, monitoring, management, and investment.

Open-File Report↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 12

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as a part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 12, Missouri log numbers 12195 and 12339, are given in this report. The drill hole is located in sec. 18, T. 34 N., R. 5 W. in Reynolds County. Data of the whole-rock samples are listed in table 1, and data of the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 3

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 3, Missouri log number 18839, are given in this report. The drill hole is located in sec. 3, T. 34 N., R. 2 W., in Iron County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 5

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 5, Missouri log number 21245, are given in this report. The drill hole is located in sec. 4, T. 30 N., R. 1 E., in Reynolds County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 7

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 7, Missouri log number 20185, are given in this report. The drill hole is located in sec. 33, T. 28 N., R. 1 E., in Reynolds County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 8

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 8, Missouri log number 21589, are given in this report. The drill hole is located in sec. 12, T. 27 N., R. 1 W., in Carter County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 10

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 10, Missouri log number 25824, are given in this report. The drill hole is located in sec. 25, T. 32 N., R. 10 W., in Texas County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 11

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole No. 11, Missouri log number 2246, are given in this report. The drill hole is located in sec. 3, T. 34 N., R. 6 W., in Dent County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 13

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 13, Missouri log numbers 24240, 21956, and 23814 are given in this report. The drill hole is located in sec. 30, T. 31 N., R. 4 W., in Shannon County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill holes no. 14 and 15

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 14, Missouri log numbers 27179 and 21181, and for drill hole no. 15, Missouri log number 26598, are given in this report. Drill hole no. 14 is located in sec. 32, T. 37 N., R. 2 E., in Washington County, and drill hole no. 15 is located in sec. 25, T. 38 N., R. 4 E., in St. Francois County.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 16

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 16, Missouri log numbers 21231 and 23857, are given in this report. The drill hole is located in sec. 1, T. 29 N., R. 6 E., in Wayne County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 17

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 17, Missouri log number 22812, are given in this report. The drill hole is located in sec. 10, T. 27 N., R. 3 E., in Wayne County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill holes no. 18, 19, and 20

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 18, Missouri log numbers 24244 and 20974, drill hole no. 19, Missouri log numbers 20967 and 23863, and for drill hole no. 20, Missouri log number 20154, are given in this report. Drill hole no. 18 is located in sec. 13, T. 33 N., R. 1 W., in Reynolds County, drill hole no. 19 is located in sec. 2, T. 34 N., R. 1 W. in Iron County, and drill hole no. 20 is located in sec. 16, T. 35 N., R. 1 W. in Washington County. Data for the whole-rock samples for drill hole no. 18 are listed in table 1, and data for the insoluble-residue samples for drill hole no. 18 are listed in table 2.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill holes no. 23 and 24

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 23, Missouri log numbers 21239 and 23878, and for drill hole no. 24, Missouri log number 12320, are given in this report. Drill hole no. 23 is located in sec. 8, T. 28 N., R. 6 E., in Wayne County, and drill hole no. 24 is located in sec. 9, T. 35 N., R. 2 W., in Crawford County.

Missouri↗

Spectrographic and chemical analyses of whole-rock and insoluble-residue samples, Rolla 1 degree x 2 degrees quadrangle, Missouri: Drill hole no. 25

Geochemical studies of the Rolla, Mo., 1° x 2° quadrangle were begun in 1977 as part of a joint multidisciplinary study of the quadrangle by the U.S. Geological Survey and the Division of Geology and Land Survey, Missouri Department of Natural Resources. The study is to access the mineral resource potential of the area by integrated geologic, geochemical, and geophysical studies. The geochemical work to date has been directed at the characterization of the sedimentary and igneous rocks in the quadrangle through spectrographic and chemical analyses of whole-rock samples and dilute-hydrochloric-acid insoluble-residue samples of whole rock from widely spaced drill holes. Sixty-two drill holes have been selected for study from the sample library of the Missouri Division of Geology and Land Survey. None of the holes are company-confidential, none intersect economically significant mineralized ground, and only a few are located in known ore-bearing trends. The analytical results for drill hole no. 25, Missouri log number 22394, are given in this report. The drill hole is located in sec. 27, T. 38 N., R. 3 E., in Washington County. Data for the whole-rock samples are listed in table 1, and data for the insoluble-residue samples are listed in table 2. Missouri log number, county, and location allow correlation with the stratigraphic logs on file at the Missouri Division of Geology and Land Survey in Rolla, Mo.

Missouri↗