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The northwest margin of the California continental borderland consists mainly of two northwest-trending pre-Neogene lithologic belts blanketed by Miocene and younger strata. These belts, which are lithologically and structurally correlated with the Franciscan Complex and Great Valley sequence of northern California, are interpreted to represent facies corresponding to the subduction...

Historical production statistics are used to predict the quantity of remaining usable resources. The commodities considered are mercury, copper and its byproducts gold and silver, and petroleum; the production and discovery data are for the United States. The results of the study indicate that the cumulative return per unit of...

At 8.32 a.m. on 18 May 1980, failure of the upper part of the north slope of Mount St Helens triggered a lateral eruption ('the blast') that devastated the conifer forests in a sector covering ???500 km2 north of the volcano. I present here a steady flow model for the...

In the northern Great Plains, large quantities of biogenic methane are contained at shallow depths in Cretaceous marine mudstones. The Gammon Shale and equivalents of the Milk River Formation in Canada, which comprise most sediments deposited offshore during the Eagle-Telegraph Creek regression, are typical of such gas-bearing rocks. At Little...

A sequential extraction scheme is utilized to determine the geochemical partitioning of Cu, Zn and Pb among hydrous Mn- and Fe-oxides, organics and residual crystalline silicates and oxides in the minus-80-mesh (< 0.18 mm) sediments and in boulder coatings from a stream in Lincoln County, Georgia (U.S.A.). The stream drains...

The Fraunhofer line discriminator (FLD), an airborne electro-optical instrument designed to measure solar-stimulated luminescence, has a sensitivity approaching that of current laboratory fluorescence spectrometers. The feasibility of using an airborne FLD for detection of near-coastal and open-ocean phytoplankton was established by using a laboratory fluorescence spectrometer to measure the luminescence...

Previous interest in light hydrocarbons from geothermal systems has focused principally on the origin of the methane1 and the estimation of subsurface temperatures from the carbon isotopic content of coexisting methane and carbon dioxide1-3. Higher molecular weight hydrocarbons were first reported in gases from Yellowstone National Park4, and have since...

Upper Cretaceous (Campanian and Maestrichtian) marine strata of the Rosario Group in the San Diego area include the Point Loma Formation and overlying Cabrillo Formation. These units contain six facies associations: (1) shelf and lagoonal sandstone, (2) slope and basin-plain(?) mudstone, (3) outer-fan lobe sandstone, (4) middle-fan channel-fill sandstone, (5)...

An atomic-absorption spectrophotometric method with electrothermal atomisation has been developed for the determination of selenium in geological materials. The sample is decomposed with a mixture of nitric, perchloric and hydrofluoric acids and heated with hydrochloric acid to reduce selenium to selenium(IV). Selenium is then extracted into toluene from a hydrochloric...

Various wood fragments buried in sediments under anaerobic conditions for from 450 yr to approximately 8 Myr have been examined by solid-state 13C nuclear magnetic resonance. Cellulose and other carbohydrates, the major components of Holocene wood, have been shown to be gradually hydrolyzed or otherwise lost under the conditions of...

Three Mile Island (TMI) and Peach Bottom (PB) reactors have introduced 137Cs, 134Cs, 60Co, 58Co and several other anthropogenic radionuclides into the lower Susquehanna River. Here we present the release history for these nuclides (Table 1) and radionuclide concentration data (Table 2) for sediment samples collected in the river and...

U-Th-Pb systematics were investigated in 15 samples representing two types of deuterically altered Archean granite (albitized and silicified-epidotized granite) from the Granite Mountains, Wyoming. The loss of K-feldspar during both types of deuteric alteration was accompanied by an extreme reduction of Pb content from roughly 40 ppm to less than...

Rates of sedimentation calculated from analyses of 210Pb activities in cores from two shallow lakes whose mean depths are 2.4m, Upper Klamath Lake and Lake Euwana (Klamath County, Oregon), indicate that they are filling at approximately 3.0mm/yr. Average sedimentation rates for compaction-corrected cores range from 0.9mm/yr to 8.5mm/yr or from...

Geochemical studies in the central Brooks Range, Alaska, delineate a regional, structurally controlled mineral belt in east—west-trending metamorphic rocks and adjacent metasedimentary rocks. The mineral belt extends eastward from the Ambler River quadrangle to the Chandalar and Philip Smith quadrangles, Alaska, from 147° to 156°W. longitude, a distance of more...

Geodetic measurements made in this century demonstrate that modern movements correlate well with deformation that has occurred during the past 2 m.y. Both show effects of subduction and of the Quaternary collision of Izu Peninsula with Central Honshu. Westward from Suruga Bay, deformation is greatest near the coast, decreases markedly...

The potentiometric surface of the Wilcox-Carrizo aquifer in central northwestern Louisiana is shown by contours using data collected from 1960 to 1980. The aquifer is not affected by regional water-level declines as no large pumping centers have been developed. Seasonal water-level fluctuations in wells are generally less than 10 feet...

Flow through fractures is often idealized as flow between two parallel plates (plane Poiseuille flow). The opening or aperture between parallel plates is unambiguous and its relation to flowrate is well known. However, fractures in rock have uneven walls and a variable aperture. A model for flow in a fracture...

The development of an effective vaccine to infectious hematopoietic necrosis virus (IHNV) in fish requires a knowledge of the virus serotypes in nature. At least two serotypes were found among three IHNV strains (12). Attempts in our laboratory to extend this study with additional virus strains by classical immunological techniques...

A September 1981 potentiometric-surface map of the Southwest Florida Water Management District depicts the annual high water-level period. Water levels in most wells measured in September 1981 are equal to or higher than in May 1981. Levels averaged about 26 feet higher in the southern part of the area and...

Fecal extracts and blood sera from 113 ducks showing clinical signs of botulism were examined for Clostridium botulinum type C toxin by means of the mouse toxicity test to evaluate coproexamination as a diagnostic procedure, as compared with demonstration of toxin in serum. When death of test mice unprotected with type...

Castor bean (Ricinus communis) poisoning accounted for the death of several thousand ducks in the Texas panhandle in the fall and winter months of 1969-1971.Signs of intoxication resembled those of botulism, except for mucoid, blood-tinged excreta. The most common lesions were severe fatty change in the liver, widely distributed internal...

Of the three types of remotely sensed data discussed here, Landsat data offers the greatest potential for monitoring broad changes in extensive tropical forest environments because of its low-cost, synoptic, repetitive coverage. Scientists from developing countries can choose from a variety of Landsat data classification techniques, thus enabling each country...

The Golden Eagle (Aquila chrysaetos) is the largest predatory bird in North America and is well known for its predatory abilities. Attacks have been reported on mammals such as whitetail jackrabbits (Lepus townsendi) (McGahan 1967, J. Wildl. Mgmt. 31: 496), pronghorn antelope (Antilocapra americana) (Bruhns 1970, Can. Field-Natur. 84: 301),...

A study of the gains or losses of the Sevier River and the Central Utah, McIntyre, and Leamington Canals in the Leamington area, in Juab and Millard Counties, Utah, was made to determine changes in those reaches. Three to seven sets of seepage measurements made during 1980 were used in...

Continued K-Ar dating of intrusive rocks and hydrothermal alteration zones in the Chignik and Sutwik Island quadrangles of the Alaska Peninsula, supplemental to that by Wilson, Detterman, and Silberman (1978) and Wilson (1978), has refined our knowledge of the ages of the igneous rocks and clarified relations between altered zones...