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Research about California, Nevada

Source-linked reports with geographic coverage including California, Nevada.

At least 325 records · Page 18Linked to original sources
USGS1977

Reconnaissance examination of the biology, chemistry, and physical characteristics of selected streams in California and Nevada

This report contains hydrological data from several California and Nevada streams. Emphasis is placed upon water-quality data, but stream discharge at the time of making the water-quality measurements also is given. The purpose of the report is to provide personnel of the U.S. Bureau of Land Management with baseline hydrological data from the selected streams and one well. The streams, the stream sites selected for sampling, and the parameters measured, were chosen in consultation with U.S. Bureau of Land Management personnel.

California, Nevada↗
USGS1977

Appraisal of the water resources of Death Valley, California-Nevada

The hydrologic system in Death Valley is probably in a steady-state condition--that is, recharge and discharge are equal, and net changes in the quantity of ground water in storage are not occurring. Recharge to ground water in the valley is derived from interbasin underflow and from local precipitation. The two sources may be of the same magnitude. Ground water beneath the valley moves toward the lowest area, a 200-square-mile saltpan, much of which is underlain by rock salt and other saline minerals, probably to depths of hundreds of feet or even more than 1,000 feet. Some water discharges from the saltpan by evaportranspiration. Water beneath the valley floor, excluding the saltpan, typically contains between 3,000 and 5,000 milligrams per liter of dissolved solids. Water from most springs and seeps in the mountains contains a few hundred to several hundred milligrams per liter of dissolved solids. Water from large springs that probably discharge from interbasin flow systems typically contains between 500 and 1,000 milligrams per liter dissolved solids. Present sites of intensive use by man are supplied by springs, with the exception of the Stovepipe Wells Hotel area. Potential sources of supply for this area include (1) Emigrant Spring area, (2) Cottonwood Spring, and (3) northern Mesquite Flat. (Woodard-USGS)

California, Nevada↗
USGS1974

Preliminary results from a search for regional tectonomagnetic effects in California and western Nevada

Physical theory and laboratory experiments both indicate that tectonomagnetic effects in seismically active areas should be detected with highly sensitive drift-free differential magnetometers. By using a pair of synchronized 0.25 7 absolute magnetometers to measure precisely field differences between 70 adjacent sites with a 10–15 km separation, more than 1,000 km of faults in California and western Nevada have been monitored for anomalous changes in the local magnetic field. Over a nine-month period, four sets of mea surements have been completed along 350 km of the San Andreas and two sets along the Excelsior Mountains, Mono Lake, and Owens Valley. Preliminary results show that significant changes have occurred between each subsequent data set and that these changes appear to be related to tectonic structure and seismicity. This method looks promising as a simple inexpensive scheme for indicating some hazardous sections of active faults, particularly in countries where extensive geophysics programs are not feasible.

California, Nevada↗
USGS1974

Long term flow of the Truckee River in California and Nevada

The Office of the Solicitor, Department of the Interior, requested the Geological Survey to evaluate the reliability of streamflow records in the Truckee River basin and to determine the long-term average annual runoff. The reliability of streamflow records was evaluated by comparisons between pairs of records at six locations along the Truckee River between Lake Tahoe and Pyramid Lake. The observed or estimated annual runoff near Nixon, Nevada was adjusted for changes in storage, evaporation losses, diversions, and depletions to approximate the inflow into Pyramid Lake under natural conditions. The long-term average annual runoff near Nixon was computed on the basis of streamflow records since 1899. The long-term (124-year) record of precipitation at Sacramento and tree ring information were used to substantiate the conclusion that the average runoff during the 74 years of streamflow record is a reliable measure of the average runoff for a longer period.

California, Nevada↗
USGS1974

Correlation of uppermost Precambrian and lower Cambrian strata from southern to east-central Nevada

Study of exposed uppermost Precambrian and Lower Cambrian strata in southern and east-central Nevada and intervening areas indicates that the Johnnie Formation of southern Nevada and the McCoy Creek Group (restricted) are correlative. In detail, the uppermost units of both sequences, the Rainstorm Member of the Johnnie Formation and the Osceola Argillite (and the equivalent unit G) of the McCoy Creek Group, arc lithologically similar and also considered correlative. Both are characterized by pale-red or purplish-medium-gray siltstone with abundant bedding-surface markings, and both contain scarce to abundant amounts of evenly or lenlicularly laminated limestone or silty limestone. Both units are lithologically unique in their respective areas of occurrence, and both are known to be widely distributed. Several thousand feet of dominantly detrital rocks occur above the Johnnie Formation in southern Nevada and the McCoy Creek Group in east-central Nevada. These detrital rocks consist of quartzite and siltstone in southern Nevada (the Stirling Quartzite, Wood Canyon Formation, and Zabriskie Quartzite) and dominantly quartzite (the Prospect Mountain Quartzite) in cast-central Nevada. Study in areas between southern and east-central Nevada indicates that the Stirling, Wood Canyon, and Zabriskie Formations change facies to the north and become lithologically similar to one another. The Prospect Mountain Quartzite of east-central Nevada is believed to be the final result of the facies change. It is equivalent to the combined Stirling, Wood Canyon, and Zabriskie of southern Nevada.

California, Nevada↗
USGS1973

Granitic rocks of the White Mountains area, California-Nevada: Age and regional significance

Potassium-argon ages have been determined on 25 biotite and hornblende samples (four coexisting biotite-hornblende pairs were dated) from a number of granitic formations in the more than 500 sq mi of dominantly granitic outcrop in the White Mountains. These new data, together with earlier published radiometric ages, indicate a group of plutons about 70 to 85 m.y. old, a single body about 210 m.y. old, another that may be about 225 m.y. old, and several between 130 and 185 m.y. old. Evidence of intrusion is lacking in the intervals of about 90 to 130 m.y. and 185 to 200 m.y. The oldest age, about 226 m.y., may represent the chance preservation of a “primary” hornblende in a body in which the dark minerals are largely recrystallized and their radiometric ages reset. This age suggests that Triassic magmatism may be more widespread along the eastern margin of the Sierra Nevada batholith than had previously been considered. The radiometric age data from the White Mountains, together with similar data from northwestern and north-central Nevada and abundant data from the central Sierra Nevada, suggest essentially continuous, albeit irregular, magmatic activity from Triassic to the end of Cretaceous, except for periods of little or no activity in earliest Jurassic and earliest Cretaceous. Episodes of magmatic activity may, and probably do, characterize specific areas, but when sufficiently large blocks of the Sierra Nevada batholith are considered, the sum of the episodes approaches a continuum.

California, Nevada↗
USGS1972

Deuterium content of snow as an index to winter climate in the Sierra Nevada area

The winter of 1968-69 produced two to three times the amount of precipitation in the Sierra Nevada area, California and Nevada, as the winter of 1969-70. The deuterium content in snow cores collected at the end of each winter at the same sites, which represents the total snowfall of each interval, shows a depletion in 1968-69 of approximately 20 per mil. The higher snowfall in 1968-69 and the depletion of deuterium can be explained by an uncommonly strong westward flow of cold air over and down the western slopes of the Sierras, which interacted with an eastward flow of moist Pacific air that overrode and mixed with the cold air; this resulted in precipitation that occurred in greater than normal amounts and at a lower than normal temperature. Pluvial periods of the Pleistocene may have had the same shift in air-mass trajectory as the wet 1968-69 year. Snow cores collected in the normal 1970-71 winter have deuterium concentrations that resemble those of the normal 1969-70 winter. Small and nonsystematic differences in samples from these two normal winters are due to variations in climatic character as well as to factors inherent in the sampling sites.

California, Nevada↗
USGS1971

Wells and springs in California and Nevada within 100 miles of point 37°15' N, 116°25' W, on Nevada test site

Studies of published and unpublished geologic and ground-water data, for an inventory of 6,032 wells and 754 springs in parts of Inyo and Mono Counties, California, and Clark, Esmeralda, Lincoln, and Nye Counties, Nevada, reveal the following information: A complex sequence of granitic, metamorphic, volcanic, and sedimentary rocks of Precambrian to Holocene age are present in the study area. Rocks of lower Precambrian age are metamorphic. These rocks can be divided into five principal types: (a) valley fill, (b) volcanic, (c) carbonate, (d) clastic, and (e) metamorphic and granitic. The valley fill which produces large amounts of water is the best aquifer and it contains the largest number of wells. The carbonate and the volcanic rocks produce small to large amounts of water from fractures or solution cavities. The clastic rocks and the metamorphic and granitic racks produce very little ground water. The greatest concentration of wells in the study area is in the Las Vegas area, which has 79 percent of the total wells inventoried. The Las Vegas area has less than 1 percent of the springs inventoried. The major uses of ground water listed in order of abundance, for the area exclusive of Las Vegas, are irrigation, domestic, public supply, and industrial. The major uses of ground water listed in order of abundance in the Las Vegas area are domestic, irrigation, public supply, and commercial.

California, Nevada↗