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An integrated geophysical study - comprising gravity, seismic refraction, and aeromagnetic surveys - was made of a 4,600-km2 area in Grand Teton National Park and vicinity, Wyoming, for the purpose of obtaining a better understanding of the structural relationships in the region. The Teton range is largely comprised of Precambrian...

Properties of sand waves formed by subcritical unidirectional water currents are investigated by statistical analyses of records of streambed profiles. Records of bed elevation y as a function of distance x along the channel, y = y(x), and time records at a fixed point of the channel, y = y(t),...

The '500-foot' sand is the major source of water supply for the Memphis area. Thick layers of impervious clay above and below the sand confine the water in the aquifer under artesian pressure and also protect the aquifer from contamination. Recharge from rainfall enters the '500-foot' sand in the outcrop,...

Water-discharge, velocity, and slope variations for a 3.7-mile-Iong tidal reach of the Willamette River at Portland, Oreg., were defined from discharge measurements and river stage data collected between July 1962 and January 1965. Observed water discharge during tide-affected flows, during floods, and during backwater from the Columbia River and recorded...

This report describes the most outstanding floods in the United Spates during 1962. The most damaging floods during the year occurred in February in southern Idaho and northern Nevada and Utah, and during the latter part of February and the early part of March in Kentucky and in the Cumberland...

Although the total supply of water in King County is large, water problems are inevitable because of the large and rapidly expanding population. The county contains a third of the 3 million people in Washington, most of the population being concentrated in the Seattle metropolitan area. King County includes parts...

The Salt River Valley and the lower Santa Cruz River basin are the two largest agricultural areas in Arizona. The extensive use of ground water for irrigation has resulted in the need for a thorough appraisal of the present and future ground-water resources. The ground-water reservoir provides 80 percent (3.2...

The Gore Canyon-Kremmling area is in the southwestern portion of the Kremmling 15-minute quadrangle, Colorado. Precambrian rocks are biotite gneiss, the Boulder Creek Granodiorite, granophyre dikes, and quartz veins. The Boulder Creek intrudes the biotite gneiss, and both of these units are cut by north-northwest-trending granophyre dikes and quartz veins....

Bornu and Dikwa Emirates lie in the Nigerian sector of the Chad Basin, a vast region of interior drainage encompassing about 600,000 square miles of north-central Africa. The report area includes about 25,000 square miles of the basin that lie in Nigeria. Most of the area is a featureless plain...

The change in water use as a result of the modification of riparian vegetation was measured in Cottonwood Wash, Mohave County, Ariz. A 4.1-mile length of the stream channel was selected and divided into a 2.6-mile upper reach and a 1.5-mile lower reach. Measurements of streamflow, ground-water levels, vegetation, and...

The Deer Lodge Valley is a basin trending north-south within Powell, Deer Lodge, and Silver Bow Counties in west-central Montana, near the center of the Northern Rocky Mountains physiographic province. It trends northward between a group of relatively low, rounded mountains to the east and the higher, more rugged Flint...

A study of methods of collecting and processing samples to determine whether or not gold is present in areas of moderate size was undertaken in the northwestern part of the San Juan Mountains, Colo. As part of this study, 57 samples of pan concentrates were taken from streams draining three...

Lava Beds National Monument is on the Modoc Plateau in Modoc and Siskiyou Counties. The principal geologic units in the vicinity are volcanic rocks, which in places are highly permeable and poorly permeable lake sedimentary deposits, all probably post-Oligocene in age. Yields and specific capacities of wells in the unconfined...

The Bighorn River has incised a deep, broad valley in Cretaceous strata along its 65-mile lower reach below the mouth of Bighorn Canyon in south-central Montana. It ceased downcutting at six different levels 100-200 feet apart, widening its flood plain and alluviating each level with about 30 feet of sandy...

Accurate measurement of water levels deeper than 1,000 feet in wells requires specialized equipment. Corrections for stretch and thermal expansion of measuring tapes must be considered, and other measuring devices must be calibrated periodically. Bore-hole deviation corrections also must be made. Devices for recording fluctuation of fluid level usually require...

The meteorite classes of Prior and Mason are assigned to three proposed genetic groups on the basis of a combination of compositional, mineralogical, and elemental characteristics: l) the calcium-poor, volatile-rich carbonaceous chondrites and achondrites; 2) the calcium-poor, volatile-poor chondrites (enstatite, bronzite, hypersthene, and pigeonite), achondrites (enstatite, hypersthene, and pigeonite), stonyirons...

The Mahoning River drains the densely populated and industrialized Warren-Youngstown area in northeastern Ohio. Significant chemical constituents and physical properties generally regarded as important in establishing water-quality standards for the Mahoning River are evaluated on the basis of hydrologic conditions and water use. Most of the interpretations and the appraisal...

The Golden Zone mine area, in the upper Chulitna district, is underlain mainly by siltstone and tuff, volcanic conglomerate and breccia, and limestone. These rocks were invaded, probably in the Tertiary, by dikes and a small stock of porphyry. The ore deposits of the area are the Golden Zone breccia...

The mass transfer-water budget method of computing reservoir evaporation was tested on Warm Springs Reservoir, whose contents and surface area change greatly from early spring to late summer. The mass-transfer coefficient computed for the reservoir is two to three times greater than expected and results in a computed evaporation much...

Monmouth County includes an area of 538 square miles in east-central New Jersey. The climate is characterized by moderate temperature, moderate humidity, and moderate precipitation. The exposed rocks in the area are chiefly sands and clays, which range in age from Late Cretaceous through Recent. The formations strike northeast-southwest and dip...

Montmorillonite was found to be the dominant clay mineral in surface horizons of certain soils of the North Carolina Coastal Plain whereas a 2:1-2:2 intergrade clay mineral was dominant in subjacent horizons. In all soils where this clay mineral sequence was found, the surface horizon was low in pH (below...

Various physical and chemical processes may be envisioned which will cause anomalous pressures on an underground fluid. In order to consider the maintenance of anomalous pressure, it is necessary to consider the problem as one of nonsteady fluid flow. The time rate of pressure change and maintenance depends upon the...

Resurgent cauldrons are defined as cauldrons (calderas) in which the cauldron block, following subsidence, has been uplifted, usually in the form of a structural dome. Seven of the best known resurgent cauldrons are: Valles, Toba, Creede, San Juan, Silverton, Lake City, and Timber Mountain. Geologic summaries of these and Long...