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At least 1,459 records · Page 81Linked to original sources
USGS2002

Characterization of soils and rock at an active oil production site: Effects of brine and hydrocarbon contamination

An active oil production site (Osage-Skiatook petroleum environmental research Site B) in Osage County, Oklahoma is under study to determine the impacts on soils and rock of brine and hydrocarbon spills. The goals of the soil and rock characterization are to 1) document and identify the type, degree, and areal extent of brine and hydrocarbon releases, 2) understand controls on the movement and retention of brine and hydrocarbons, and 3) determine the role of solid phases, such as clay and iron-bearing minerals, in natural mitigation. The types and amounts of clay minerals and oxidizers (particularly iron) are important because of the capacity of clay minerals to exchange cations that are dissolved in brines and the capacity of reactive ferric iron species to oxidize hydrocarbons. Characterization of soils and rock includes visual and microscopic description, X-ray diffraction of bulk and clay fraction samples, separation of size fractions, determination of cation exchange capacity, bulk chemical composition, and selective extraction of iron species. Results suggest that much of the brine and hydrocarbon contamination occurs in the shallow subsurface (< 240 cm) where the soil profile varies from dark brown topsoil to reddish orange sand to greenish-gray clay. A layer of iron-stained colluvium that is present in the shallow subsurface consists of pebbles and coarse sand and forms an important conduit for fluid movement. Unusually high percentages (as much as 97 % of total iron) of reduced iron may record the passage of hydrocarbon-rich ground water. Clay minerals are abundant in some samples and are dominated by kaolinite, mixed layer illite-smectite, and smectite. The correlation of grain size and clay mineral content with soil leachate results will be discussed and high percentages of sodium on exchange sites in clay are expected in areas of past spills of produced water.

Oklahoma↗
USGS2016

Low-flow characteristics for streams on the Islands of Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi, State of Hawaiʻi

Statistical models were developed to estimate natural streamflow under low-flow conditions for streams with existing streamflow data at measurement sites on the Islands of Kauaʻi, O ʻ ahu, Moloka ʻ i, Maui, and Hawai ʻ i. Streamflow statistics used to describe the low-flow characteristics are flow-duration discharges that are equaled or exceeded between 50 and 95 percent of the time during the 30-year base period 1984–2013. Record-augmentation techniques were applied to develop statistical models relating concurrent streamflow data at the measurement sites and long-term data from nearby continuous-record streamflow-gaging stations that were in operation during the base period and were selected as index stations. Existing data and subsequent low-flow analyses of the available data help to identify streams in under-represented geographic areas and hydrogeologic settings where additional data collection is suggested. Low-flow duration discharges were estimated for 107 measurement sites (including long-term and short-term continuous-record streamflow-gaging stations, and partial-record stations) and 27 index stations. The adequacy of statistical models was evaluated with correlation coefficients and modified Nash-Sutcliff coefficients of efficiency, and a majority of the low-flow duration-discharge estimates are satisfactory based on these regression statistics. Molokaʻi and Hawaiʻi have the fewest number of measurement sites (that are not located on ephemeral stream reaches) at which flow-duration discharges were estimated, which can be partially explained by the limited number of index stations available on these islands that could be used for record augmentation. At measurement sites on some tributary streams, low-flow duration discharges could not be estimated because no adequate correlations could be developed with the index stations. These measurement sites are located on streams where duration-discharge estimates are available at long-term stations at other locations on the main stream channel to provide at least some definition of low-flow characteristics on that stream. In terms of general natural streamflow data availability, data are scarce in the leeward areas for all five islands as many leeward streams are dry or have minimal flow. Other under-represented areas include central Oʻahu, central Maui, and southeastern Maui.

Hawaiʻi↗
USGS2017

Diet, feeding patterns, and prey selection of subyearling Atlantic salmon (Salmo salar) and subyearling chinook salmon (Oncorhynchus tshawytscha) in a tributary of Lake Ontario

Since juvenile Atlantic salmon ( Salmo salar ) and Chinook salmon ( Oncorhynchus tshawytscha ) occupy a similar habitat in Lake Ontario tributaries, we sought to determine the degree of diet similarity between these species in order to assess the potential for interspecific competition. Atlantic salmon, an historically important but currently extirpated component of the Lake Ontario fish community, are the focus of a bi-national restoration effort. Presently this effort includes the release of hatchery produced juvenile Atlantic salmon in Lake Ontario tributaries. These same tributaries support substantial numbers of naturally reproduced juvenile Pacific salmonids including Chinook salmon. Subyearling Atlantic salmon and subyearling Chinook salmon had significantly different diets during each of the three time periods examined. Atlantic salmon fed slightly more from the benthos than from the drift and consumed mainly chirononmids (47.0%) and ephemeropterans (21.1%). The diet of subyearling Chinook salmon was more closely associated with the drift and consisted mainly of chironomids (60.2%) and terrestrial invertebrates (16.0%). Low diet similarity between subyearling Atlantic salmon and subyearling Chinook salmon likely minimizes competitive interactions for food between these species in Lake Ontario tributaries. However, the availability of small prey such as chironomids which comprise over 50% of the diet of each species, soon after emergence, could constitute a short term resource limitation. To our knowledge this is the first study of interspecific diet associations between these two important salmonid species.

Journal of Applied Ichthyology↗
USGS1983

SUBMICROSCOPIC ( less than 1 mu m) MINERAL CONTENTS OF VITRINITES IN SELECTED BITUMINOUS COAL BEDS.

An important aspect of the petrographic description of coal is the characterization of coal quality, including chemical attributes. For geologic investigations, data on the concentrations, distribution, and modes of occurrence of minor and trace elements provide a basis for reconstructing the probable geochemical environment of the swamp material that was converted into peat, and the geochemical conditions that prevailed during and subsequent to coalification. We have been using electron (EPMA) and proton (PIXE) microprobe analytical methods to obtain data on the chemical characteristics of specific coal constituents in their original associations within coal samples. The present study is aimed at evaluation of the nature of mineral occurrences and heterogeneous elemental concentrations within vitrinites. Vitrinites are usually the most abundant, and therefore most important, maceral group in bituminous coal. 8 refs.

Conference Paper↗
USGS2012

An atlas of Mars sedimentary rocks as seen by HiRISE

Images of distant and unknown places have long stimulated the imaginations of both explorers and scientists. The atlas of photographs collected during the Hayden (1872) expedition to the Yellowstone region was essential to its successful advocacy and selection in 1872 as America’s first national park. Photographer William Henry Jackson of the Hayden expedition captured the public’s imagination and support, returning home with a treasure of images that confirmed the existence of western landmarks previously regarded as glorified myths: the Grand Tetons, Old Faithful, and strange pools of boiling hot mud. Fifty years later, photographer Ansel Adams began his long legacy of providing the public with compilations of iconic images of natural wonders that many only see in prints. Photography in space has provided its own bounty. Who can forget the first image of Earthrise taken by astronaut William Anders in 1968 from Apollo 8; the solemnity of the first photos of the surface of the Moon from the Apollo 11 astronauts; and the startling discovery of the tallest mountain in the solar system (Olympus Mons) on the surface of Mars in images sent from Mariner 9? The images from Mariner 9 also allowed for a game-changing discovery. Earlier, based on very limited Mariner 4 data that covered less than 10% of the planet’s surface, Chapman et al. (1968) speculated that “If substantial aqueous erosion features—such as river valleys— were produced during earlier epochs of Mars, we should not expect any trace of them to be visible.

Book chapter↗
USGS2011

Geophysical logs and water-quality data collected for boreholes Kimama-1A and -1B, and a Kimama water supply well near Kimama, southern Idaho

In September 2010, a research consortium led by scientists from Utah State University began drilling the first of three continuously cored boreholes on the Snake River Plain in southern Idaho. The goals of this effort, the Snake River Scientific Drilling Project, are to study the interaction between the Earth's crust and mantle, to identify potential geothermal energy sources, and to track the evolution of the Yellowstone hotspot on the Snake River Plain. The first borehole, located near Kimama, Idaho, is about 50 miles southwest of the U.S. Department of Energy's Idaho National Laboratory. Because geohydrologic data are scarce for that area of the central Snake River Plain, the Kimama borehole, completed in January 2011, provided a unique opportunity to collect geophysical and water-chemistry data from the eastern Snake River Plain aquifer system, downgradient of the laboratory. Therefore, in conjunction with the Snake River Scientific Drilling Project, scientists from the U.S. Geological Survey's Idaho National Laboratory Project Office conducted geophysical logging and collected water samples at the Kimama site. Wireline geophysical logs were collected for the diverging borehole, Kimama-1A and -1B, from land surface to 976 and 2,498 feet below land surface (BLS), respectively. Water samples were collected from Kimama-1A at depths near 460 and 830 feet BLS, and from the Kimama Water Supply (KWS) well located about 75 feet away. Geophysical log data included a composite of natural gamma, neutron, gamma-gamma dual density, and gyroscopic analysis for boreholes Kimama-1A and -1B. Geophysical logs depicted eight sediment layers (excluding surficial sediment) ranging from 4 to 60 feet in thickness. About 155 individual basalt flows were identified, ranging from less than 3 feet to more than 175 feet in thickness (averaging 15 feet) for borehole Kimama-1B (0 to 2,498 feet BLS). Sediment and basalt contacts were selected based on geophysical traces and were confirmed with visual inspection of core photographs. Temperature logs from the water table surface (about 260 feet BLS) to the bottom of borehole Kimama-1B (2,498 feet BLS) were nearly isothermal, ranging from about 62 to 64 degrees Fahrenheit. Gyroscopic data revealed that borehole Kimama-1B begins to separate from borehole Kimama-1A near a depth of 676 feet BLS. Drillhole azimuth and horizontal deviation at total logged depth for boreholes Kimama-1A and -1B were 172.6 and 188.3 degrees and 25.9 and 82.0 feet, respectively. Water samples were collected and analyzed for common ions; selected trace elements; nutrients; isotopes of hydrogen, oxygen, and carbon; and selected radionuclides. One set of water samples was collected from the KWS well and the two other sample sets were collected from borehole Kimama-1A near 460 and 830 feet BLS. With one exception, data for all three zones sampled near Kimama generally indicated that the water chemistry was similar. The exception was found in the deepest zone in borehole Kimama-1A (830 feet BLS) where concentrations probably were affected by the drilling mud. A comparison of the inorganic, organic, and stable chemistry data between the KWS well and the 460-foot zone in borehole Kimama-1A indicated similar chemistry of the aquifer water, except for some variability with nitrate plus nitrite, orthophosphate, iron, zinc, and carbon-14. Radionuclide concentrations were either less than reporting levels or at background levels for the eastern Snake River Plain aquifer.

Idaho↗
USGS2003

Native plants for effective coastal wetland restoration

Plant communities, along with soils and appropriate water regimes, are essential components of healthy wetland systems. In Louisiana, the loss of wetland habitat continues to be an issue of major concern. Wetland loss is caused by several interacting factors, both natural and human-induced (e.g., erosion and saltwater intrusion from the construction of canals and levees). Recent estimates of annual coastal land loss rates of about 62 km2 (24 mi2 ) over the past decade emphasize the magnitude of this problem. In an attempt to slow the rate of loss and perhaps halt the overall trend, resource managers in Louisiana apply various techniques to restore damaged or degraded habitats to functioning wetland systems. Researchers at the U.S. Geological Survey’s National Wetlands Research Center (NWRC) have cooperated with the Louisiana Department of Natural Resources in studies that address effective restoration strategies for coastal wetlands. The studies have identified differences in growth that naturally exist in native Louisiana wetland plant species and genetic varieties (i.e., clones) within species. Clones of a species have a distinctive genetic identity, and some clones may also have distinctive growth responses under various environmental conditions (i.e., preferences). Indeed, large areas of coastal marsh are typically populated by several clones of a plant species, each growing in a microenvironment suited to its preferences. These studies will provide information that will assist resource managers in selecting plant species and clones of species with known growth characteristics that can be matched to environmental conditions at potential restoration sites. Before the studies began, a collection of several clones from four plant species native to coastal Louisiana was established. The species collected included saltgrass (Distichlis spicata), common reed (Phragmites australis), giant bulrush (Schoenoplectus californicus), and saltmarsh bulrush (Schoenoplectus robustus). Plants connected by roots were collected from public lands across the coastal zone, and then allowed to grow several months and produce new stems and plants from underground stems called “rhizomes.” These procedures maintained the genetic identity of the clones and allowed the plants to adjust to greenhouse conditions before experimental treatments began.

Fact Sheet↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗
USGS1978

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↗