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A preliminary study of the feasibility of using geophysical exploration methods to locate abandoned wells containing steel casing indicated that magnetic methods promise to be effective and that some electrical techniques might be useful as auxiliary methods. Ground magnetic measurements made in the vicinity of several known cased wells yielded...

The deposition rate of atmospheric Pb-210 has been measured during a one year period using plastic funnels as collectors. Observed rates were 0.15 dpm cm−2 yr−1 at a site in Palo Alto, California and 0.21 dpm cm−2 yr−1 at a site in Los Angeles. The Palo Alto value agrees well with a long-term average...

A record of glaciation during late Proterozoic time is preserved in a number of localities extending from the Sheeprock Mountains, Utah, to Pocatello, Idaho, and from the Park City area 40 km east of Salt Lake City to the Deep Creek Range along the Utah-Nevada line. Over much of this...

A gravity survey of the Jiddah area between lat 21°23' and 21°48' N., long 39°03' and 39°20' E., carried out in early 1977, covers an area of 744 km2 and includes 215 stations, at an average spacing of 1.9 km. The resulting simple Bouguer gravity anomaly map shows a series...

The solubility of plutonium in Mono Lake water is enhanced by the presence of large concentrations of indigenous carbonate ions and moderate concentrations of fluoride ions. In spite of the complex chemical composition of this water, only a few ions govern the behavior of plutonium, as demonstrated by the fact...

Strain accumulation and release at a subduction zone are attributed to stick slip on the main thrust zone and steady aseismic slip on the remainder of the plate interface. This process can be described as a superposition of steady state subduction and a repetitive cycle of slip on the main...

Drilling fluids or "muds" are essential components of modern drilling operations. They provide integrity for the well bore, a medium for removal of formation cuttings, and lubrication and cooling of the drill bit and pipe. The modeling workshop described in this report was conducted September 14-18, 1981 in Gulf Breeze,...

Four stratigraphic sections through alkali basalt flows of Oligocene to Miocene age (29‐24 Ma) in the As Sarat volcanic field, south‐western Saudi Arabia, were sampled for palaeomagnetic study. After systematic alternating‐field demagnetization, 42 magnetically acceptable flows (139 samples) yield a mean direction of magnetization of =355.3°, =15.2° (α=4.3°), which defines...

Two landslide scars (slide tracks) were plot sampled one and two years after landsliding to determine plant species involved in ecesis. The study site is located in a blockfield cove on Massanutten Mountain, northern Virginia. Old growth forest, adjacent to the slide tracks, is composed primarily of hemlock (Tsuga canadensis)...

The diffusion equation derived from the continuity equation for hillslopes is applied to scarp erosion in unconsolidated materials. Solutions to this equation allow direct calculation of the product of the rate coefficient and the age of the scarp from measurements of scarp morphology. Where the rate coefficient can be estimated...

The effect of serial dependence on the reliability of an estimate of the T-yr. event is of importance in hydrology because design decisions are based upon the estimate. In this paper the reliability of estimates of the T-yr. event from two common distributions is given as a function of number of observations...

A block of pitchstone in the northern Black Hills, South Dakota, is Paleocene in age, according to potassium-argon dating of biotite and fission-track dating of zircon in the sample. These data invalidate published suggestions that the age is much younger. The pitchstone is not extrusive in its present position but...

The solubility of a 44° API (0.806 sp. gr.) whole crude oil has been measured in methane with water present at temperatures of 50 to 250°C and pressures of 740 to 14,852 psi, as have the solubilities of two high molecular weight petroleum distillation fractions at temperatures of 50 to...

In September 1980, the U. S. Geological Survey conducted a seismic refraction investigation of the northern Mississippi Embayment. During the investigation, 34 shots from nine shotpoints were recorded along a series of profiles. The profiles were parallel to and across an inferred Precambrian rift zone which is outlined by a...

The sulfur content of 1,225 samples of Green River oil shale from two core holes in the Piceance Creek Basin, Colorado, ranges from nearly 0 to 4.9 weight percent. In one core hole, the average sulfur content of a sequence of oil shale 555 m thick, which represents nearly the...

No abstract available....

Igneous rocks commonly have large magnetic susceptibilities so that high topographic relief in crystalline terrane can produce significant anomalies in aeromagnetic surveys. Topographic anomalies are particularly significant in relatively undeformed volcanic terrane because young volcanic rocks generally have large natural remanent magnetizations as well as large susceptibilities. These anomalies commonly...

No abstract available....

The Platte River Forum for the Future (PRFF) is an effort by the Nebraska Natural Resources Commission (NNRC) to bring together representatives of interests and agencies concerned with management of the Platte River and, assisted by various computer technologies, to reach some degree of agreement on the “best uses” of...

The U.S. Environmental Protection Agency (EPA) needs a comprehensive method to evaluate the human health and environmental effects of alternative agricultural pest management strategies. This project explored the utility of Adaptive Environmental Assessment (AEA) techniques for meeting this need. The project objectives were to produce models for environmental...

This report summarizes information produced from Interagency Agreement No. AA-851-IA1-27 between the Bureau of Land Management (BLM), USDI, and the Fish and Wildlife Service (FWS), USDI. The contract was instrumental in the final development of wildlife guilds for the Hualapai-Aquarius planning area of the BLM in westcentral Arizona, reported...

During the quadrennial term 1979–1982, major advances have been made in our knowledge of the rheology of the oceanic lithosphere by the skillful combination of experimental and theoretical rock mechanics, seismology and marine geophysics in increasingly sophisticated models for the flexure of the oceanic lithosphere at seamounts and island chains,...

Modern pollen surface samples from six lake and marsh sites in the northern California Coast Ranges establish a linear relation between elevation and the oak/(oak + pine) pollen ratio. Modern temperature and precipitation lapse rates were used to convert variations in the pollen ratio into temperature and...

Paleomagnetic and geological data suggest that much of southern Alaska is a collage of tectonostratigraphic terranes which originated in Mesozoic time at paleolatitudes far south of their present position. The time of ‘docking’ of the terranes against cratonic Alaska is critical to defining their amalgamated size and extent during their...