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Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

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At least 1,351 records · Page 75Linked to original sources
USGS2010

Seamounts and ferromanganese crusts within and near the U.S. EEZ off California - Data for RV Farnella cruise F7-87-SC

The purpose of this report is to present and briefly describe ship-board and laboratory data for a U.S. Geological Survey (USGS) research cruise aboard the RV Farnella that took place December 3-21, 1987 (cruise F7-87-SC). The purpose of the cruise was to survey seamounts and ferromanganese crusts within and near the U.S. Exclusive Economic Zone (EEZ) off California. Eight seamounts were studied - Rodriguez, San Marcos, Adam, Hoss, Little Joe, Ben, Flint, and Jasper. A geophysical survey of Jasper Seamount took place, but that seamount was not sampled; whereas Adam and Hoss Seamounts were sampled, but not surveyed with geophysics lines.

California↗
USGS2013

Chuckwalla Valley multiple-well monitoring site, Chuckwalla Valley, Riverside County

The U.S. Geological Survey (USGS), in cooperation with the Bureau of Land Management, is evaluating the geohydrology and water availability of the Chuckwalla Valley, California. As part of this evaluation, the USGS installed the Chuckwalla Valley multiple-well monitoring site (CWV1) in the southeastern portion of the Chuckwalla Basin. Data collected at this site provide information about the geology, hydrology, geophysics, and geochemistry of the local aquifer system, thus enhancing the understanding of the geohydrologic framework of the Chuckwalla Valley. This report presents construction information for the CWV1 multiple-well monitoring site and initial geohydrologic data collected from the site.

California↗
USGS2020

Multiple-well monitoring site adjacent to the North and South Belridge Oil Fields, Kern County, California

The U.S. Geological Survey (USGS), in cooperation with the California State Water Resources Control Board, is evaluating several questions about oil and gas development and groundwater resources in California, including (1) the location of groundwater resources; (2) the proximity of oil and gas operations to groundwater and the geologic materials between them; (3) evidence (or no evidence) of fluids from oil and gas sources in groundwater; and (4) the pathways or processes responsible when fluids from oil and gas sources are present in groundwater (U.S. Geological Survey, 2017). As part of this evaluation, the USGS installed a multiple-well monitoring site in the southern San Joaquin Valley groundwater basin adjacent to the North and South Belridge oil fields, about 7 miles southwest of Lost Hills, California. Data collected at the Belridge multiple-well monitoring site (BWSD) provide information about the geology, hydrology, geophysical properties, and geochemistry of the aquifer system, thus enhancing understanding of relations between adjacent groundwater and the North and South Belridge oil fields in an area where there are few groundwater data. This report presents construction information for the BWSD and initial hydrogeologic data collected from the site. A similar site installed to the east of the Lost Hills oil field, 11.5 miles to the north of the BWSD site, was described by Everett and others (2020a).

California↗
USGS2017

Hydrology of the Claiborne aquifer and interconnection with the Upper Floridan aquifer in southwest Georgia

The U.S. Geological Survey conducted a study, in cooperation with the Georgia Environmental Protection Division, to define the hydrologic properties of the Claiborne aquifer and evaluate its connection with the Upper Floridan aquifer in southwest Georgia. The effort involved collecting and compiling hydrologic data from the aquifer in subarea 4 of southwestern Georgia. Data collected for this study include borehole geophysical logs in 7 wells, and two 72-hour aquifer tests to determine aquifer properties. The top of the Claiborne aquifer extends from an altitude of about 200 feet above the North American Vertical Datum of 1988 (NAVD 88) in Terrell County to 402 feet below NAVD 88 in Decatur County, Georgia. The base of the aquifer extends from an altitude of about 60 feet above NAVD 88 in eastern Sumter County to about 750 feet below NAVD 88 in Decatur County. Aquifer thickness ranges from about 70 feet in eastern Early County to 400 feet in Decatur County. The transmissivity of the Claiborne aquifer, determined from two 72-hour aquifer tests, was estimated to be 1,500 and 700 feet squared per day in Mitchell and Early Counties, respectively. The storage coefficient was estimated to be 0.0006 and 0.0004 for the same sites, respectively. Aquifer test data from Mitchell County indicate a small amount of leakage occurred during the test. Groundwater-flow models suggest that the source of the leakage was the underlying Clayton aquifer, which produced about 2.5 feet of drawdown in response to pumping in the Claiborne aquifer. The vertical hydraulic conductivity of the confining unit between the Claiborne and Clayton aquifers was simulated to be about 0.02 foot per day. Results from the 72-hour aquifer tests run for this study indicated no interconnection between the Claiborne and overlying Upper Floridan aquifers at the two test sites. Additional data are needed to monitor the effects that increased withdrawals from the Claiborne aquifer may have on future water resources.

Georgia↗
USGS2014

The need for a nation‐wide program of observation‐wells

During the severe droughts of recent years almost the only water‐supplies available throughout large areas of the United States have been those obtained from underground sources. Consequently, a great interest has developed in the ground‐water resources of the country and there has been much concern lest the declining water‐levels in wells and the diminished flow of springs may be warnings of the ultimate exhaustion of our ground‐water supplies. As is well known, the United States Geological Survey has for half a century conducted investigations of the ground‐water of the country and numerous investigations have been made by State geological surveys and other agencies. However, the time is now ripe for a coordinated, continuing program to obtain systematic records of water‐levels in observation ‐ wells and correlative records of natural discharge and artificial withdrawals of ground‐water.

Eos, Transactions, American Geophysical Union↗
USGS2014

The nickel deposits of Yakobi Island, southeastern Alaska

Some of the large, low‐grade nickel‐copper deposits of Bohemia Basin, Yakobi Island, south‐eastern Alaska, which previously had been mapped and studied by the United States Geological Survey, were explored during parts of 1941 and 1942 by the United States Bureau of Mines. The Gealogical Survey interpreted the geologic features of the deposits as revealed by the work of the Bureau of Mines. The explorations were made largely by diamond‐drilling. The three deposits most extensively tested are arranged around a small valley.

Alaska↗
USGS2014

Report of Committee on Glaciers, 1942–43

The personnel of the Committee at present is as follows: Harry Fielding Reid, Professor Emeritus of Geology, Johns Hopkins University, 608 Cathedral Street, Baltimore, Maryland William H. Hobbs, Professor Emeritus of Geology, University of Michigan, Ann Arbor, Michigan Colonel Lawrence Martin, Chief, Division of Maps, Library of Congress, Washington, D.C. James E. Church, Professor of Meteorology and President, International Commission of Snow and Glaciers, Agricultural Experiment Station, University of Nevada, Reno, Nevada First Lieutenant William Osgood Field, Jr., home address, 18 West Twelfth Street, New York City Oliver Kehrlein, Chairman, Committee on Glacier Studies, Sierra Club, 1050 Mills Tower, San Francisco, California Kenneth N. Phillips, Associate Hydraulic Engineer, Water Resources Branch, Geological Survey, Chairman, Research Committee of the Masamas, 606 Post‐Office Building, Portland, Oregon William S. Cooper, Professor of Botany, University of Minnesota, Minneapolis, Minnesota Lieutenant Colonel Gerald FitzGerald, Army Air Corps, Washington, D.C. Laurence M. Gould, Professor of Geology, Carleton College, Northfield, Minnesota Arthur Johnson, Hydraulic Engineer, Conservation Branch, Geological Survey, 1105 Washington Building, Tacoma, Washington François E. Matthes (Chairman), Senior Geologist, Section of Glacial Geology, Geological Survey, Washington, D.C. The Committee is fortunate in having its membership reinforced by the addition of ARTHUR JOHNSON, who for several years has had charge of the repetitive plane‐table surveys of the lower Nisqually Glacier, on Mount Rainier—a project which the Geological Survey is carrying on in cooperation with the city of Tacoma, Washington. To him the Committee is indebted for data concerning the losses in volume of ice which the Nisqually Glacier is sustaining from year to year.

Eos, Transactions, American Geophysical Union↗
USGS2014

Water‐level fluctuations caused by Montana earthquake

The major earthquake of August 17, 1959, near the Montana‐Wyoming border had marked effects on water levels and artesian pressures in wells throughout the United States. Preliminary reports from field offices of the U. S. Geological Survey in 21 states show that water‐level fluctuations were automatically recorded in 136 observation wells. These wells for which records are available, and the maximum double amplitude of the fluctuations, are listed in Table 1.

Eos, Transactions, American Geophysical Union↗
USGS1997

On the origin of diverse aftershock mechanisms following the 1989 Loma Prieta earthquake

We test the hypothesis that the origin at the diverse suite of aftershock mechanisms Following the 1989 M 7.1 Loma Prieta, California, earthquake is related to the post-main-shock static stress field We use a 3-D boundary-element algorithm to calculate static stresses combined with a Coulomb failure criterion to calculate conjugate failure planes at aftershock locations. The post-main-shock static stress field is taken as the of a sum of a pre-existing stress field and changes in stress due to the heterogeneous slip across the Loma Prieta rupture plane. The background stress field is assumed to be either a simple shear parallel to the regional trend of the San Andreas fault or approximately fault-normal compression A suite of synthetic aftershock mechanisms from the conjugate failure planes is generated and quantitatively compared (allowing for uncertainties in both mechanism parameters and earthquake locations) to well-constrained mechanisms reported in the US Geological Survey Northern California Seismic Network catalogue. We also compare calculated rakes with those observed by resolving the calculated stress tensor onto observed focal mechanism nodal planes, assuming either plane to be a likely rupture plane.

Geophysical Journal International↗
USGS2014

Hydrostratigraphic interpretation of test-hole and borehole geophysical data, Kimball, Cheyenne, and Deuel Counties, Nebraska, 2011-12

Recently (2004) adopted legislation in Nebraska requires a sustainable balance between long-term supplies and uses of surface-water and groundwater and requires Natural Resources Districts to understand the effect of groundwater use on surface-water systems when developing a groundwater-management plan. The South Platte Natural Resources District (SPNRD) is located in the southern Nebraska Panhandle and overlies the nationally important High Plains aquifer. Declines in water levels have been documented, and more stringent regulations have been enacted to ensure the supply of ground-water will be sufficient to meet the needs of future generations. Because an improved understanding of the hydrogeologic characteristics of this aquifer system is needed to ensure sustainability of groundwater withdrawals, the U.S. Geological Survey, in cooperation with the SPNRD, Conservation and Survey Division of the University of Nebraska-Lincoln, and the Nebraska Environmental Trust, began a hydrogeologic study of the SPNRD to describe the lithology and thickness of the High Plains aquifer. This report documents these characteristics at 29 new test holes, 28 of which were drilled to the base of the High Plains aquifer. Herein the High Plains aquifer is considered to include all hydrologically connected units of Tertiary and Quaternary age. The depth to the base of aquifer was interpreted to range from 37 to 610 feet in 28 of the 29 test holes. At some locations, particularly northern Kimball County, the base-of-aquifer surface was difficult to interpret from drill cutting samples and borehole geophysical logs. The depth to the base of aquifer determined for test holes drilled for this report was compared with the base-of-aquifer surface interpreted by previous researchers. In general, there were greater differences between the base-of-aquifer elevation reported herein and those in previous studies for areas north of Lodgepole Creek compared to areas south of Lodgepole Creek. The largest difference was at test hole 5-SP-11, where an Ogallala-filled paleovalley prevously had been interpreted based on relatively sparse test-hole data west of 5-SP-11. The base of aquifer near test hole 5-SP-11 reported herein is approximately 230 ft higher in elevation than previously interpreted. Among other test holes that are likely to have been drilled in Ogallala-filled paleovalleys, the greatest difference in the interpreted base of aquifer was for test hole 7-CC-11, northeast of Potter, Nebraska, where the base of aquifer is 180 feet deeper than previously interpreted. Interpretation of test-hole and borehole geophysical data for 29 additional test holes will improve resource managers’ understanding of the hydrogeologic characteristics, including aquifer thickness. Aquifer thickness, which is related to total water in storage, is not well quantified in the north and south tablelands. The additional hydrostratigraphic interpretations provided in this report will improve the hydrogeologic framework used in current (2014) and future groundwater models, which are the basis for many water-management decisions.

Nebraska↗
USGS1995

K1-95-HW: Cruise report 1995 - Preliminary results, phase III: Sediment chemistry and biological sampling survey

Mamala Bay, off the south shore of the island of Oahu, has been used as a repository of dredged material primarily from Pearl and Honolulu Harbors for over a century. The U.S. Geological Survey, U.S. Army Corps of Engineers, and the U.S. Environmental Protection Agency are conducting an integrated study on the distribution and character of dredged materials as well as the effects of dredged material on the marine environment. A three phase study is providing information to evaluate the effects on seafloor substrate and the benthic fauna. The studies include geophysical profiling and imaging, bottom photography, sampling, chemical and physical analyses of sediment, and evaluations of the benthic population, population density, and adverse impacts to the benthic fauna. Phase 1, conducted in 1993, inventoried the seafloor via remote sensing. Sidescan sonar and subbottom profilers characterized the seafloor in and around the disposal sites, and the resulting products reveal the character and extent of the dredged material. These data were used to plan Phase 2 in 1994, a sampling program that employed subbottom profilers, video and still photography, and seafloor sampling to ground truth the sonar mosaic and identify the seafloor substrates responsible for the various acoustic signatures on the sonar images and subbottom profiles. Box coring provided the samples necessary to distinguish dredged material from native sediment, and for the chemical analyses used to determine contaminant concentrations. Phase 3 studies conducted in June of 1995 consisted of box core sampling for chemical and biological analyses. Specific studies include: infaunal taxonomy and population density, bioassay/bioaccumulation, sediment chemistry, and post-disposal resuspension and transport. The 1995 survey, conducted June 14 through 17, resulted in the collection of 39 box cores from 20 different stations. Multiple box cores were composited at 7 different locations occupied in 1994, to provide the material required for the 7 bioassay and bioaccumulation analyses currently underway (Figure 1). Seventeen of the 20 stations occupied provided the biological samples for the benthic infaunal identification and population density study conducted by Dr. Julie Brock of the University of Hawaii, and the sediment chemistry analyses conducted (and completed) by Quanterra Environmental Laboratories (Figure 1). Seven of the 20 stations occupied in 1995 were occupied in 1994, and provide the data for direct comparison of sediment chemistry at the same sites from two consecutive years. The sum total of the data collected from all three phases of the monitoring program will provide the U.S. Army Corps of Engineers and the U.S. Environmental Protection Agency with the information required to make informed decisions as to the management of the South Oahu disposal site in Mamala Bay.

Hawai'i↗
USGS1978

The Aleutian Basin, Bering Sea a frontier area for hydrocarbon exploration

The Aleutian Basin is the deep water (>3000 m) basin that lies north of the Aleutian Islands adjacent to the Bering Sea continental shelf. The basin, about the size of the state of Texas, is underlain by a 2-9 km-thick flat-lying sequence of mostly Cenozoic sediment and rock that includes diatomaceous silty clay interbedded with turbidities in the upper 1 km. Before 1974, geologic and geophysical investigations in the Aleutian Basin were directed at determining its geologic history; more recently, investigations have also been aimed at assessing the basin's hydrocarbon potential. The four major requirements for hydrocarbon accumulation may be present, namely, structural and stratigraphic traps, source rocks, reservoir beds, and an adequate thermal and sedimentation history. Energy resource investigations by the US Geological Survey indicate that: (1) numerous structural features (gentle folds, diapirs, basement ridges) are present in the central and eastern parts of the basin, (2) acoustic features (VAMP's _ Velocity AMPlitude features) that may be due to trapped gases within the sedimentary section are common (over 350 identified) in the central basin, (3) concentrations of organic gases, primarily methane, in the upper 1-3 m beneath the seafloor are very small, they increase with depth, and they are highest in areas near VAMP's, and (4) both the thermal gradient and the sediment thickness are sufficiently great to allow hydrocarbon maturation at depth, if source rocks are present. Adverse conditions in the Aleutian Basin such as excessive water depths and severe weather pose difficult technical problems for the recovery of hydrocarbons that may be present. The data nevertheless suggest the basin is a promising site for hydrocarbon accumulations and therefore warrants further exploration.

Conference Paper↗
USGS2018

Revisiting the Apollo photogrammetric mapping system

The integrated photogrammetric mapping system flown on the last three Apollo lunar missions (15, 16, and 17) in 1971 and 1972 incorporated a Metric (mapping) Camera, a high-resolution Panoramic Camera, and a star camera and laser altimeter to provide support data. The U.S. Geological Survey’s Astrogeology Science Center, the Intelligent Robotics Group of the NASA Ames Research Center, and Arizona State University are working together in an ongoing collaboration to achieve the most complete cartographic development of Apollo mapping system data into versatile digital map products. These will enable a variety of scientific/engineering uses of the data including mission planning, geologic mapping, geophysical process modelling, slope dependent correction of spectral data, and change detection. After a brief discussion of the origins of the mapping system, we describe the Metric and Panoramic cameras, processing of the associated image and support data, work to photogrammetrically control the Metric Camera images, and future plans.

Conference Paper↗
USGS2000

Standardizing the nomenclature of Martian impact crater ejecta morphologies

The Mars Crater Morphology Consortium recommends the use of a standardized nomenclature system when discussing Martian impact crater ejecta morphologies. The system utilizes nongenetic descriptors to identify the various ejecta morphologies seen on Mars. This system is designed to facilitate communication and collaboration between researchers. Crater morphology databases will be archived through the U.S. Geological Survey in Flagstaff, where a comprehensive catalog of Martian crater morphologic information will be maintained.

Journal of Geophysical Research E: Planets↗
USGS2020

Alkalic-type epithermal gold deposit model

This report summarizes the primary characteristics of alkalic-type epithermal gold (Au) deposits and provides an updated descriptive model. These deposits, primarily of Mesozoic to Neogene age, are among the largest epithermal gold deposits in the world. Considered a subset of low-sulfidation epithermal deposits, they are spatially and genetically linked to small stocks or clusters of intrusions containing high alkali-element contents. Deposits occur as disseminations, breccia-fillings, and veins and may be spatially and genetically related to skarns and low-grade porphyry copper (Cu) or molybdenum (Mo) systems. Gold commonly occurs as native gold, precious metal tellurides, and as sub-micron gold in arsenian pyrite. Quartz, carbonate, fluorite, adularia, and vanadian muscovite/roscoelite are the most common gangue minerals. Alkalic-type gold deposits form in a variety of geological settings including continent-arc collision zones and back-arc or post-subduction rifts that are invariably characterized by a transition from convergent to extensional or transpressive tectonics. The geochemical compositions of alkaline igneous rocks spatially linked with these deposits span the alkaline-subalkaline transition. Their alkali enrichment may be masked by potassic alteration, but the unaltered or least altered rocks (1) have chondrite normalized patterns that are commonly light rare earth element (LREE) enriched, (2) are heavy rare earth element (HREE) depleted, and (3) have high large ion lithophile contents and variable enrichment of high-field strength elements. Radiogenic isotopes suggest a mantle derivation for the alkalic magmas but allow crustal contamination. Oxygen and hydrogen isotope compositions show that the fluids responsible for deposit formation are dominantly magmatic, although meteoric or other external fluids (seawater, evolved groundwater) also contributed to the ore-forming fluids responsible for these deposits. Carbon and sulfur isotope compositions in vein-hosted carbonates and sulfide gangue minerals, respectively, coincide with magmatic values, although a sedimentary source of carbon and sulfur is evident in several deposits. Deep-seated structures are critical for the upwelling of hydrous alkalic magmas and for focusing magmatic-hydrothermal fluids to the site of precious metal deposition. The source of gold, silver (Ag), tellurium (Te), vanadium (V), and fluorine (F) was probably the alkalic igneous rocks themselves, and the coexistence of native gold, gold tellurides, and roscoelite in several deposits is primarily a function of similar physicochemical conditions during deposition (for example, overlapping pH and oxygen fugacity ( f O2). Potential environmental impacts related to the mining and processing of alkalic-type epithermal gold deposits include acid mine drainage with high levels of metals, especially zinc (Zn), copper, lead (Pb), and arsenic. However, because alkalic-type gold deposits typically contain carbonates, which contribute calcium and magnesium ions that increase water hardness, aquatic life may be afforded some protection. Impacts vary widely as a function of host rocks, climate, topography, and mining methods. Geologic mapping to (1) highlight the distribution of potassic alteration; (2) define fault density and orientation of structures; (3) determine the distribution of alkaline rocks and hydrothermal breccias; and (4) identify uniquely colored gangue minerals, such as fluorite and roscoelite, will be critical to exploration and future discoveries. Geophysical techniques that identify potassium (K) anomalies (for example, radiometric and spectroscopic surveys), as well as magnetic, resistivity, aeromagnetic, and gravity surveys, may help locate zones of high-permeability that control advecting hydrothermal fluids. Geochemical surveys that include analyses for Au, Ag, barium, Te, K, F, V, Mo, and mercury, which are key elements in these deposits, should be undertaken along with the measurement of other pathfinder elements such as arsenic, bismuth, Cu, iron, nickel, Pb, antimony, selenium, and Zn.

Scientific Investigations Report↗
USGS1952

Geophysical observations in parts of the Grants District, McKinley County, New Mexico

Geophysical observations near Haystack Mesa in the Grants district, McKinley County, New Mexico, had the dual objective of investigating the unusual occurrence of negative aeromagnetic anomalies in close association with airborne radioactivity anomalies, and of investigating other geophysical methods which might assist directly or indirectly in the search for uranium ores in the Grants district. Ground magnetometer tests indicate the apparent correlation shown in the airborne data is fortuitous. Ground magnetometer and self-potential surveys on an experimental basis may be justified to test the applicability of these methods in future exploration. Aeroagnetic surveys would aid field geologic studies in locating concealed Tertiary intrusives, which may have affected ore localization. Continuation of the airborne radiometric survey of the Todilto limestone outcrop is recommended to search for promising areas that might contain additional deposits.

New Mexico↗
USGS2007

Matching magnetic trends and patterns across the Tintina fault, Alaska and Canada--evidence for offset of about 490 kilometers: Chapter C in Recent U.S. Geological Survey studies in the Tintina Gold Province, Alaska, United States, and Yukon, Canada--results of a 5-year project

Magnetic anomaly patterns on opposite sides of the mapped Tintina fault in eastern Alaska and western Canada show an apparent offset of about 490 kilometers (km), probably of Eocene age. This estimate is compared with previous geologically based estimates of 400 to 430 km and paleomagnetically based estimates of more than 1,100 km. The apparent geophysical alignments have geologic implications that deserve further study.

Alaska;Yukon↗
USGS2014

Welded rhyolitic tuffs in southeastern Idaho

Rocks of rhyolitic type in eastern Idaho and adjacent parts of Wyoming were observed by the Teton Division of the Hayden Surveys under Orestes St. John (Report of the geological field work of the Teton Division, U.S. Geol. and Geog. Surv. Terr., 11th Ann. Rep., pp. 498–504, 1879), who described them as trachytes. He noted their relations to different types of underlying sedimentary rocks and their tendency to conform with the preexisting topography, but considered them all as flows. ©1935. American Geophysical Union. All Rights Reserved.

Idaho↗