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At least 127 records · Page 7Linked to original sources
USGS1966

Disequilibrium of the 238U series in basalt

Radioisotope analyses of basalt samples from Hawaii, Japan, and Iwo Jima show that: (1) 234 U and 238 U are virtually in radioactive equilibrium, (2) 230 Th exceeds equilibrium values in all these samples, (3) 210 Pb concentrations range from 10–200% of the equilibrium values and average 30% deficient, and (4) 226 Ra is probably not in equilibrium with 234 U. The source regions of the basalts or magma forming processes are open systems, chemically. The enrichment of some of the uranium-daughter nuclides is insufficient to account for the excess 206 Pb in volcanic rocks. The isotopic composition of lead and specific activity of 210 Pb in sublimates from Showa-shinzan, Japan are also reported.

Hawaii↗
USGS2007

Investigation of magnesium isotope fractionation during basalt differentiation: Implications for a chondritic composition of the terrestrial mantle

To investigate whether magnesium isotopes are fractionated during basalt differentiation, we have performed high-precision Mg isotopic analyses by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) on a set of well-characterized samples from Kilauea Iki lava lake, Hawaii, USA. Samples from the Kilauea Iki lava lake, produced by closed-system crystal-melt fractionation, range from olivine-rich cumulates to highly differentiated basalts with MgO content ranging from 2.37 to 26.87 wt.%. Our results demonstrate that although these basalts have diverse chemical compositions, mineralogies, crystallization temperatures and degrees of differentiation, their Mg isotopic compositions display no measurable variation within the limits of our external precision (average δ 26 Mg = − 0.36 ± 0.10 and δ 25 Mg = − 0.20 ± 0.07; uncertainties are 2SD). This indicates that Mg isotopic fractionation during crystal-melt fractionation at temperatures of ≥ 1055 °C is undetectable at the level of precision of the current investigation. Calculations based on our data suggest that at near-magmatic temperatures the maximum fractionation in the 26 Mg/ 24 Mg ratio between olivine and melt is 0.07‰. Two additional oceanic basalts, two continental basalts (BCR-1 and BCR-2), and two primitive carbonaceous chondrites (Allende and Murchison) analyzed in this study have Mg isotopic compositions similar to the Kilauea Iki lava lake samples. In contrast to a recent report [U. Wiechert, A.N. Halliday, Non-chondritic magnesium and the origins of the inner terrestrial planets, Earth and Planetary Science Letters 256 (2007) 360–371], the results presented here suggest that the Bulk Silicate Earth has a chondritic Mg isotopic composition.

Hawaii↗
USGS2011

Contribution of global groundwater depletion since 1900 to sea-level rise

Removal of water from terrestrial subsurface storage is a natural consequence of groundwater withdrawals, but global depletion is not well characterized. Cumulative groundwater depletion represents a transfer of mass from land to the oceans that contributes to sea-level rise. Depletion is directly calculated using calibrated groundwater models, analytical approaches, or volumetric budget analyses for multiple aquifer systems. Estimated global groundwater depletion during 1900–2008 totals ~4,500 km 3 , equivalent to a sea-level rise of 12.6 mm (>6% of the total). Furthermore, the rate of groundwater depletion has increased markedly since about 1950, with maximum rates occurring during the most recent period (2000–2008), when it averaged ~145 km 3 /yr (equivalent to 0.40 mm/yr of sea-level rise, or 13% of the reported rate of 3.1 mm/yr during this recent period).

Geophysical Research Letters↗
USGS2016

Reply to “Comment on ‘Ground motions from the 2015 Mw 7.8 Gorkha, Nepal, earthquake constrained by a detailed assessment of macroseismic data’ by Stacey S. Martin, Susan E. Hough, and Charleen Hung” by Andrea Tertulliani, Laura Graziani, Corrado Castellano, Alessandra Maramai, and Antonio Rossi

We thank Andrea Tertulliani and his colleagues for their interest in our article on the 2015 Gorkha earthquake (Martin, Hough, et al., 2015), and for their comments pertaining to our study (Tertulliani et al., 2016). Indeed, as they note, a comprehensive assessment of macroseismic effects for an earthquake with far‐reaching effects as that of Gorkha is not only critically important but is also an extremely difficult undertaking. In the absence of a widely known web‐based system, employing a well‐calibrated algorithm with which to collect and systematically assess macroseismic information (e.g., Wald et al., 1999; Coppola et al., 2010; Bossu et al., 2015) in the Indian subcontinent, one is left with two approaches to characterize effects of an event such as the Gorkha earthquake: a comprehensive ground‐based survey such as the one undertaken in India following the 2001 Bhuj earthquake (Pande and Kayal, 2003), or an assessment such as Martin, Hough, et al. (2015) akin to other contemporary studies (e.g., Nuttli, 1973; Sieh, 1978; Meltzner and Wald, 1998; Martin and Szeliga, 2010; Ambraseys and Bilham, 2012; Mahajan et al., 2012; Gupta et al., 2013; Singh et al., 2013; Hough and Martin, 2015; Martin and Hough, 2015; Martin, Bradley, et al., 2015; Ribeiro et al., 2015), based primarily upon media reports and other available documentary accounts.

Seismological Research Letters↗
USGS1955

Records of wells drilled for oil and gas in Montana, June 1, 1951 through December 31, 1953

Data concerning about 1, 800 dry holes and selected producing wells drilled in Montana from June 1, 1951, through December 31, 1953, are contained in this circular, which supplements Circular 172 published in 1952. Also included is a table listing the oil and gas fields of Montana. WELLS DRILLED FOR OIL AND GAS IN MONTANA FROM JUNE 1, 1951, THOROUGH DECEMBER 31, 1953 This circular contains data on dry holes and selected producing wells drilled in Montana from June 1, 1951, through December 31, 1953, and supplements Circular 172 published in 1952 showing records of wells drilled prior to June 1, 1951. Table 1 lists the oil and gas fields of Montana (see map OM 130). The list of wells in table 2 has been compiled from information in Geological Survey files and includes most if not all the unsuccessful wildcat test wells and unsuccessful field extension wells drilled from June 1, 1951 to December 31, 1953. It also includes some older but successful field extension wells that had not been listed in Circular 172. Data are tabulated under location, county, field or geologic structure, operator, lease, and well number, elevation, geologic formation (at the surface and lowest formation reached), production or shows of oil or gas, total depth, and status and date. The wells are tabulated by township, range, quarter, and section in the order of townships north-ranges west, townships north-ranges east, townships south-ranges east, and townships south-ranges west. The names entered under 'Field or geologic structure' are those of the productive area or the geologic structure on or near which the wells have been drilled. Ground elevations have been given for wells for which the records indicated the reference point of the elevation. The surface formation and lowest formation reached in the wells are indicated by symbols which are identified on the accompanying explanation of formation symbols (fig. 1). Not all of the nomenclature is in accord with current Geological Survey usage. In the column 'Production or shows of oil and gas' the symbol GS is used for gas shows, OS for oil shows, GOS for shows of both gas and oil, GP for gas production, and OP for oil production. A number following the symbol for a show or production indicates the depth to the top of the zone in which the gas or oil was found. The letter symbol following the number or the hyphen indicates the geologic formation in which the gas or oil occurs. The status and depth of each well is indicated. The letters A, C, and D preceding the date indicate abandoned, completed, or drilling, respectively, in the specified year. Most if not all producing wells that have been abandoned are shown as completed wells. The date of abandonment is the year in which drilling ceased, except for a few wells in which the abandonment was preceded by one or more years of suspended operations. The diagrammatic representation of the succession of geologic formations in Montana (fig. 1) provides identification of the letter symbols used in the tabulation to indicate geologic formations.

Circular↗
USGS1997

A digital version of the 1970 U.S. Geological Survey topographic map of the San Francisco Bay region, three sheets, 1:125,000

This Open-File report is a digital topographic map database. It contains a digital version of the 1970 U.S. Geological Survey topographic map of the San Francisco Bay Region (3 sheets), at a scale of 1:125,000. These ARC/INFO coverages are in vector format. The vectorization process has distorted characters representing letters and numbers, as well as some road and other symbols, making them difficult to read in some instances. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. The content and character of the database and methods of obtaining it are described herein.

Open-File Report↗
USGS2012

Glaciotectonic deformation associated with the Orient Point-Fishers Island moraine, westernmost Block Island Sound: further evidence of readvance of the Laurentide ice sheet

High-resolution seismic-reflection profiles collected across pro-glacial outwash deposits adjacent to the circa 18 ka b.p. Orient Point–Fishers Island end moraine segment in westernmost Block Island Sound reveal extensive deformation. A rhythmic seismic facies indicates the host outwash deposits are composed of fine-grained glaciolacustrine sediments. The deformation is variably brittle and ductile, but predominantly compressive in nature. Brittle deformation includes reverse faults and thrust faults that strike parallel to the moraine, and thrust sheets that extend from beneath the moraine. Ductile deformation includes folded sediments that overlie undisturbed deposits, showing that they are not drape features. Other seismic evidence for compression along the ice front consists of undisturbed glaciolacustrine strata that dip back toward and underneath the moraine, and angular unconformities on the sea floor where deformed sediments extend above the surrounding undisturbed correlative strata. Together, these ice-marginal glaciotectonic features indicate that the Orient Point–Fishers Island moraine marks a significant readvance of the Laurentide ice sheet, consistent with existing knowledge for neighboring coeval moraines, and not simply a stillstand as previously reported.

New York↗
USGS1974

Hydrologic Unit Map -- 1974, State of Kentucky

This map and accompanying table show Hydrologic Units that are basically hydrographic in nature. The Cataloging Units shown will supplant the Cataloging Units previously used by the U.S. Geological Survey in its Catalog of Information on Water Data (1966-72). The previous U.S. Geological Survey Catalog-Indexing System was by map number and letter, such as 49M.

Kentucky↗
USGS1991

Earth Science Information Center

An ESIC? An Earth Science Information Center. Don't spell it. Say it. ESIC. It rhymes with seasick. You can find information in an information center, of course, and you'll find earth science information in an ESIC. That means information about the land that is the Earth, the land that is below the Earth, and in some instances, the space surrounding the Earth. The U.S. Geological Survey (USGS) operates a network of Earth Science Information Centers that sell earth science products and data. There are more than 75 ESIC's. Some are operated by the USGS, but most are in other State or Federal agencies. Each ESIC responds to requests for information received by telephone, letter, or personal visit. Your personal visit.

Report↗
USGS1992

Structure-contour maps on the top of the Mississippian carbonates and on the top of the upper Cambrian and lower Ordovician Arbuckle Group, Joplin 1° x 2° quadrangle, Kansas and Missouri

This publication is a part of the folio of maps of the Joplin 1° X 2° quadrangle, Kansas and Missouri, which was prepared under the Conterminuous United States Mineral Assessment Program. Other publications in this folio to date include the U.S. Geological Survey Miscellaneous Field Studies Maps MF-2125-A and B (Erickson and others, 1990; Grisafe and Rueff, 1992). Additional maps showing other geologic aspects of the Joplin quadrangle will be published as U.S. Geological Survey maps bearing this same serial number with different letter suffixes (MF-2125-D, -E, and so forth).

Kansas, Missouri↗
USGS2003

Preliminary geologic map of the Elsinore 7.5' quadrangle, Riverside County, California

Open-File Report 03-281 contains a digital geologic map database of the Elsinore 7.5’ quadrangle, Riverside County, California that includes: 1. ARC/INFO (Environmental Systems Research Institute, http://www.esri.com) version 7.2.1 coverages of the various elements of the geologic map. 2. A Postscript file to plot the geologic map on a topographic base, and containing a Correlation of Map Units diagram (CMU), a Description of Map Units (DMU), and an index map. 3. Portable Document Format (.pdf) files of: a. This Readme; includes in Appendix I, data contained in els_met.txt b. The same graphic as plotted in 2 above. Test plots have not produced precise 1:24,000-scale map sheets. Adobe Acrobat page size setting influences map scale. The Correlation of Map Units and Description of Map Units is in the editorial format of USGS Geologic Investigations Series (I-series) maps but has not been edited to comply with I-map standards. Within the geologic map data package, map units are identified by standard geologic map criteria such as formation-name, age, and lithology. Where known, grain size is indicated on the map by a subscripted letter or letters following the unit symbols as follows: lg, large boulders; b, boulder; g, gravel; a, arenaceous; s, silt; c, clay; e.g. Qyfa is a predominantly young alluvial fan deposit that is arenaceous. Multiple letters are used for more specific identification or for mixed units, e.g., Qfysa is a silty sand. In some cases, mixed units are indicated by a compound symbol; e.g., Qyf2sc. Even though this is an Open-File Report and includes the standard USGS Open-File disclaimer, the report closely adheres to the stratigraphic nomenclature of the U.S. Geological Survey. Descriptions of units can be obtained by viewing or plotting the .pdf file (3b above) or plotting the postscript file (2 above).

California↗
USGS1977

January 1977 water levels, and data related to water-level changes since 1950, western Kansas

This report contains basic data on water-level measurements in observation wells in western Kansas. Most of the measurements were made in January 1977; a few were made in December 1976 and in February 1977. The measurements were made in mid-winter when pumping was minimal and water levels had recovered from the effects of pumping during the previous irrigation season. This report also contains basic hydrologic data for 1950-77 that are provided for consideration in relation to the January 1977 water-level measurements. The annual water-level measurements are made by personnel of the Division of Water Resources of the Kansas State Board of Agriculture and of the U.S. Geological Survey. State-agency support for this program is provided through the Kansas Geological Survey. Wells in this report are numbered according to the Bureau of Land Management's system of land subdivision. In this system, the first set of digits of a well number indicates the township; the second set, the range east or west of the sixth prinicipal meridian; and the third set, the section in which the well is situated. The first letter denotes the 160-acre tract, the second, the 40-acre tract, and the third, the 10-acre tract. The letters are designated in a counterclockwise direction beginning in the northeast quarter of the section. Where there is more than one well in a 10-acre tract, consecutive numbers, beginning with "2", are added in the order in which the wells are inventoried.

Kansas↗
USGS1979

January 1979 water levels, and data related to water-level changes, western and south-central Kansas

This report contains hydrologic data on water-level measurements in observation wells in western and south-central Kansas. The measurements were made in mid-winter, mostly in January, when pumping was minimal and water levels had recovered from the effects of pumping during the previous irrigation season. This report also provides basic hydrologic data for relating water-level changes from a "base-reference year" (predevelopment year), a year of abnormally high rainfall and minimum pumpage (1966), and the previous year (1978). The "base-reference year" is designated as 1950 for the northwestern and west-central areas, 1940 for the southwestern area, and 1944 for the south-central area. Water-level data in the south-central area also are compared with data for 1974, which represents the recent period of intensified irrigation-well development. Tables in the report show the depths to water level in 1940, 1944, or 1950 (predevelopment year), 1966, 1974, 1978, and 1979; water-level changes from 1940-79, 1944-79, 1950-79, 1966-79, 1974-79, and 1978-79; and the average annual changes from 1940-79, 1944-79, 1950-79, 1966-79, and 1974-79. Also shown are saturated thicknesses of the deposits in 1940, 1944, or 1950 and in 1979, as well as the percentage change in saturated thickness from 1940-79, 1944-79, or 1950-79. The annual water-level measurements are made by personnel of the Division of Water Resources of the Kansas State Board of Agriculture and of the U.S. Geological Survey. State-agency support for this program is provided through the Kansas Geological Survey. Wells in this report are numbered according to the Bureau of Land Management's system of land subdivision. In this system, the first set of digits of a well number indicates the township; the second set, the range east or west of the sixth principal meridian; and the third set, the section in which the well is situated. The first letter denotes the 160-acre tract within the section; the second, the 40-acre tract; and the third, the 10-acre tract. The letters are designated in a counterclockwise direction beginning in the northeast quadrant. Where there is more than one well in a 10-acre tract, consecutive numbers, beginning with "2", are added in the order in which the data from the wells are collected.

Kansas↗