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R. L. Laney

Publications and source records attributed to R. L. Laney.

15 recordsLinked to original sources
USGS1996

Geohydrologic reconnaissance of Lake Mead National Recreation Area: Las Vegas Wash to Virgin River, Nevada

This study is the last of a series of eight geohydrologic reconnaissance studies that were done in the Lake Mead National Recreation Area. The studies were done to evaluate the water resources in the recreation area and to identify areas having potential for the development of water supplies that would be adequate for marinas and campgrounds. The study area includes about 250 square miles north of Lake Mead from Las Vegas Wash to the Virgin River (Overton Arm), Nevada. Volcanic rocks, consolidated sedimentary rocks, and unconsolidated to semiconsolidated sedimentary rocks underlie the area. Surface-water sources include the Colorado River, Virgin River, Muddy River, and Las Vegas Wash. Elsewhere in the area, streamflow is meager and extremely variable. Ground water originates from four sources: (1) subsurface flow in local basins, (2) infiltration of water from Lake Mead into permeable rocks near the lake, (3) subsurface flow in valleys of perennial streams, and (4) subsurface flow in consolidated rocks of the Muddy Mountains. The quantity of water from Lake Mead that has saturated rocks adjacent to the lake probably is greater than the quantity of ground water from all the other sources. Rocks saturated by water from the lake probably extend less than 0.5 mile inland from the lake shore. The quality of virtually all the ground water in the area is not acceptable for drinking purposes. The most favorable areas for obtaining ground water are those underlain by the coarse-grained deposits of the older alluvium and the younger alluvium adjacent to Lake Mead. The least favorable areas are those underlain by the mudstone facies of the Muddy Creek Formation and fine-grained rocks of the Horse Spring Formation. Four areas identified as having potential for ground-water development are (1) near Overton Beach, (2) west of Callville Bay, (3) near Middle Point, and (4) in the lower Moapa Valley. Usable quantities of water probably can be obtained at these sites, but the quality of the water may not be acceptable for drinking purposes. Test drilling for potable water supplies should be considered only as exploration.

Nevada↗
USGS1986

Hydrogeology of the eastern part of the Salt River Valley area, Maricopa and Pinal Counties, Arizona

The Salt River Valley is a major agricultural and metropolitan area in semiarid south-central Arizona. Groundwater in the permeable sedimentary deposits underlying the area is a major water supply for agricultural, municipal, and industrial users. Groundwater levels have declined as much as 400 ft in recent years. Management of the remaining groundwater resources and their protection from contamination will require knowledge of the hydrogeologic framework and the water-bearing characteristics of the sedimentary units in the groundwater system. The rocks in the eastern part of the Salt River Valley are divided into six units--crystalline rocks, extrusive rocks, red units, lower unit, middle unit, and upper unit. The crystalline and extrusive rocks underlie the basin and form virtually impermeable hydrologic boundaries. The red, lower, middle and upper sedimentary units contain most of the groundwater. The red unit contains usable quantities of ground water, principally near Scottsdale, where it yields as much as 1 ,000 gallons/min (gpm) of water to wells. The lower unit, which makes up the largest volume of sedimentary deposits, consists mostly of mudstone, clay, silt, and evaporite deposits that may be as much as 10,000 ft thick in the central part of the basin. Wells tapping the mudstone, clay, silt yield 50 (gpm) or less but the conglomerate and the sand and gravel may yield as much as 3,500 gpm. The middle unit is the principal water-bearing unit in the basin and consists mostly of silt, siltstone, and silty sand and gravel. The unit is as much as 1,000 ft thick in the central part of the basin and as much as 700 ft is saturated. The unit will yield as much as 1,000 gpm where the saturated thickness is at least 500 ft. Locally, north of Mesa, the unit yields as much as 4,000 gpm. The upper unit is gravel, sand, and silt and is saturated only in a small area in the southwestern part of the basin. Where saturated, the unit may yield as much as 4,500 gpm. The upper unit transmits recharge derived from sheet flow, from flood flow in ephemeral streams, and from irrigation to the water table. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1981

Geohydrologic reconnaissance of Lake Mead National Recreation Area: Las Vegas Wash to Opal Mountain, Nevada

The study is a geohydrologic reconnaissance of about 170 square miles in the Lake Mead National Recreation Area from Las Vegas Wash to Opal Mountain, Nevada. The study is one of a series that describes the geohydrology of the recreation area and that indentifies areas where water supplies can be developed. Precipitation in this arid area is about 5 inches per year. Streamflow is seasonal and extremely variable except for that in the Colorado River, which adjoins the area. Pan evaporation is more than 20 times greater than precipitation; therefore, regional ground-water supplies are meager except near the Colorado River, Lake Mead, and Lake Mohave. Large ground-water supplies can be developed near the river and lakes, and much smaller supplies may be obtained in a few favorable locations farther from the river and lakes. Ground water in most of the areas probably contains more than 1,000 milligrams per liter of dissolved solids, but water that contains less than 1,000 milligrams per liter of dissolved solids can be obtained within about 1 mile of the lakes. Crystalline rocks of metamorphic, intrusive and volcanic origin crop out in the area. These rocks are overlain by conglomerate and mudstone of the Muddy Creek Formation, gravel and conglomerate of the older alluvium, and sand and gravel of the Chemehuevi Formation and younger alluvium. The crystalline rocks, where sufficiently fractured, yield water to springs and would yield small amounts of water to favorably located wells. The poorly cemented and more permeable beds of the older alluvium, Chemehuevi Formation, and younger alluvium are the better potential aquifers, particularly along the Colorado River and Lakes Mead and Mohave. Thermal springs in the gorge of the Colorado River south of Hoover Dam discharge at least 2,580 acre-feet per year of water from the volcanic rocks and metamorphic and plutonic rocks. The discharge is much greater than could be infiltrated in the drainage basin above the springs. Transbasin movement of ground water probably occurs , and perhaps the larger part of the spring discharge is underflow from Eldorado Valley. The more favorable sites for ground-water development are along the shores of Lakes Mead and Mohave and are the Fire Mountain, Opal Mountain to Aztec Wash, and Hemenway Wash sites. Wells yielding several hundred gallons per minute of water of acceptable chemical quality can be developed at these sites.

Nevada↗
USGS1978

Maps showing water-level declines, land subsidence, and earth fissures in south-central Arizona

From 1915 to 1975, more than 109 million acre-feet of ground water was withdrawn from about 4,500 square miles in Pinal and Maricopa Counties in south-central Arizona. The volume of water withdrawn greatly exceeds the volume of natural recharge, and water levels have been declining since 1923. As a result of the water-level declines, the land surface has subsided, the alluvial deposits have been subjected to stress, and earth fissures have developed. Land subsidence and earth fissures have damaged public and private properties. Subsidence and fissures will continue to occur as long as ground water is being mined and water levels continue to decline. As urban development expands, land subsidence and earth fissures will have an increasing socioeconomic impact. Information on maps includes change in water levels, measurements of land subsidence, and location of earth fissures. A section showing land subsidence between Casa Grande and the Picacho Peak Interchange also is included. Scale 1:250,000. (Woodard-USGS)

Arizona↗
USGS1977

Geohydrologic reconnaissance of Lake Mead National Recreation Area; Temple Bar to Grand Wash Cliffs, Arizona

The study is one of a series of geohydrologic reconnaissance studies being made in the Lake Mead National Recreation Area and covers about 200 square miles (520 square kilometers) from Temple Bar to the Grand Wash Cliffs. Streamflow in the drainages tributary to Lake Mead is meager and extremely variable. Ground water is derived from two principal sources: (1) infiltration into permeable rocks near Lake Mead and (2) ground-water underflow in the basins that drain to the lake. The volume of ground water derived from Lake Mead is much greater than that derived from the basins. In terms of potential groundwater development the rocks saturated by lake water probably extend less than 1 mile (1.6 kilometers) from the lake, whereas the basins that contribute underflow to the lake are of much larger areal extent. The most favorable sites for ground-water development are Grapevine Mesa, Sandy Point, Hualapai Wash, and the area near and south of Temple Bar; the permeable rocks include the conglomerate facies of the Muddy Creek Formation, the older alluvium, and the Chemehuevi Formation. The least favorable areas for ground-water development are those underlain by the mudstone facies of the Muddy Creek Formation. Seven sites are recommended for future ground-water development. Five sites are within 1 mile (1.6 kilometers) of Lake Mead and two sites are between 3 and 5 miles (5 and 8 kilometers) from the lake. The ground water contains less than 1, 500 milligrams per liter of dissolved solids in most of the area. Ground water on Grapevine Mesa contains less than 500 milligrams per liter of dissolved solids, and that from springs in the metamorphic and plutonic rocks contains more than 1, 500 milligrams per liter of dissolved solids.

Arizona↗
USGS1976

Maps showing ground-water conditions in the lower Big Chino Valley and Williamson Valley areas, Yavapai and Coconino Counties, Arizona--1975-76

Arizona is divided into 67 ground-water areas, and individual areas are selected for intensive data collection once every 6 years. The data collected in the lower Big Chino Valley and Williamson Valley areas are given on maps that show depth to water, well depth, and altitude of the water level, 1975-76; pumpage, 1950-74; and specific conductance, fluoride concentration, and irrigated area, 1974. Scale 1:125,000. (Woodard-USGS)

Water-Resources Investigations Report↗
USGS1975

The influence of late Cenozoic stratigraphy on distribution of impoundment-related seismicity at Lake Mead, Nevada-Arizona

At Lake Mead, contrasts in permeability of upper Cenozoic sediments show a better correlation with irregularly distributed impoundment-related seismicity than do contrasts in structure. An evaluation of structures developed during the late Cenozoic fails to explain the erratic distribution of seismicity. An evaluation of the late Cenozoic stratigraphy, however, shows a concentration of relatively impermeable evaporite beds and fine-grained clastic strata in the less seismic part of the lake basin; therefore, the authors conclude that a hydraulic connection between the lake water and the deep aquifer system that includes buried faults is needed in the Lake Mead area to cause the release of seismic energy. Where hydraulic connection is prevented by continuous or quasi-continuous upper Cenozoic basin-fill strata of low permeability, as in the eastern basin area, seismicity does not occur.

Arizona, Nevada↗
USGS1972

Chemical quality of the water in the Tucson basin, Arizona

The Tucson basin is a broad mountain-rimmed area of about 1,000 square miles in the Basin and Range physiographic province in southeastern Arizona. The altitude ranges from 2,000 feet in the basin to as much as 8,000 feat in the mountains. The major streams in the area are the Santa Cruz River and its principal tributaries--Cafiada del Oro, Rillito Creek, and Pantano Wash. The climate is semiarid, and the distribution and amount of precipitation vary greatly. The potential evapotranspiration is about four times the average annual precipitation. The streamflow is of excellent chemical quality, although most of the flow occurs during floods and generally has large concentrations of suspended sediment. Because of the erratic occurrence and quantity of streamflow and because of the lack of surface-water storage reservoirs, all the water for municipal, industrial, and agricultural uses is obtained from the many wells that tap the permeable sedimentary deposits, which constitute the principal aquifer in the Tucson basin. The aquifer consists of three sedimentary formations that range in age from middle Tertiary to Quaternary. The aquifer is as much as 2,000 feet thick and is composed mainly of sand, gravel, sandstone, and conglomerate. The upper part of the aquifer is more permeable than the lower part, and most wells obtain water at depths of less than 700 feet below the land surface. Most ground water contains less than 500 mg/l (milligrams per liter) of dissolved solids and is of suitable chemical quality for most uses. The water to depths of as much as 700 feet is a calcium sodium bicarbonate type, is hard to moderately hard, and contains less than 1.0 mg/l fluoride. Water at greater depth is a sodium bicarbonate type, is soft, and is of excellent chemical quality; however, water below about 1,0.00 feet may contain fluoride in excess of the maximum allowable limit of 1.4 mg/l for public supply. The ground water of poorest quality for public supply is at shallow depths along the major streams, in the Pantano Formation along the northeast margin of the basin, at depth in gypsiferous mudstone, and along a narrow zone that trends northwestward across the basin. Water from these hydrologic environ- may contain as much as 500 mg/1 dissolved solids an4 in places may contain more than 1,000 mg/1 dissolved solids. The anomalously large concentrations of calcium, bicarbonate, nitrate and sulfate in the ground water along the major streams, where the water table is from 25 to 150 feet below the land surface, are the result of near-surface phenomena. The large concentrations of these ions are derived from solution of relict salts, which were deposited in marshes along the streams prior to about 1900 by infiltrating surface water. In the narrow zone the trends northwestward across the basin, the large concentrations of calcium and sulfate are the result of the solution of limestone and gypsiferous mudstone in the sedimentary rocks in the headwaters area of Pantano Wash. The largest nitrate concentrations occur in the ground water along the Santa Cruz River; the nitrate probably is derived from irrigation return water, decayed vegetation from the marshes that occupied parts of the channel prior to 1900, and sewage effluent. Anomalously large concentrations of sodium, sulfate, chloride, and fluoride occur in ground water along the Santa Cruz River near the major faults that displace the older formations. These anomalously large concentrations probably are derived from the upward leakage of deep water that has reacted with the gypsiferous mudstone in the center of the basin and moved along the faults into the near-surface deposits. In the Tucson basin the water is divided into seven chemical types based on the relative amount of four major ions--calcium, sodium, bicarbonate, and sulfate---and the absolute amount of chloride. Most of the water is either a calcium sodium bicarbonate or a sodium bicarbonate type. Gr

Water Supply Paper↗