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An outbreak of duck virus enteritis occurred in a flock of captive waterfowl composed of mallards (Anas platyrhynchos), black ducks (Anas rubripes), and Canada geese (Branta canadensis). Although all three species were housed together, morbidity and mortality were confined to the 227 black ducks and Canada geese, of which 180...

The Methyl isobutyl ketone-Amine synerGistic Iodkte Complex (MAGIC) extraction system offers the advantage that a large number of trace elements can be rapidly determined with a single sample preparation procedure. However, many of the elements extracted by the MAGIC system form volatile organometallic halide salts when the organic extract is...

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...

Measurements of D and 18O concentrations of ground waters in seismically active regions are potentially useful in earthquake prediction and in elucidating mechanisms operative during earthquakes. Principles of this method are discussed and some preliminary data regarding a magnitude 5.7 earthquake at the Oroville Dam in 1975...

On a stormy night in October 1836, H.M.S Beagle hove to and dropped anchor at Falmouth, a remote harbor in southwest England. Charles Darwin, the ship's naturalist, came ashore to take the mail coach to Shrewsbury. This was inauspicious end to an epic 5-year voyage around the coast of South...

Mr.Birge M. Clark, an architect in Palo Alto, Calif., was living in Palo Alto at the time of the 1906 earthquake. his father-in-law was Professor S. D. Townley, well known for his 1939 compilation, with Maxwell W. Allen, of earthquakes along the Pacific coast from 1769 to 1928. ...

Following on from the concepts of plate tectonics, the earth sciences are now embarking on a challenging course- the time prediction of geologic phenomena. Earthquake prediction is an outstanding example of this. However, earthquake prediction is not the only scientific goal. The destructive power of a large earthquake requires that...

Lagenostomalean-type seeds in bifurcating cupule systems have been discovered in the late Devonian Hampshire Formation of Randolph County, West Virginia, USA (Fig. 1). The associated megaflora, plants from coal balls, and vertebrate and invertebrate faunas demonstrate that the material is Famennian; the microflora indicates a more specific Fa2c age. Consequently,...

A discussion of the means employed by the US Geological Survey to facilitate map usage, covering aspects of project Map Accessibility Program including special rolled and folded map packaging, new market testing, parks and campgrounds program, expanded map dealer program, new booklet-type State sales index and catalog and new USGS...

No abstract available....

No abstract available....

The relationship between body size and concentrations of Cu and Ag varied from strongly positive to strongly negative in four populations of the bivalve Macoma balthica in San Francisco Bay. The correlations appeared to be influenced by the degree of enrichment in tissues, size-dependent differences and seasonal variations in growth rate, and...

No abstract available....

Many recently developed watershed models utilize accumulation and washoff equations to simulate the quality of runofffrom urban impervious areas. These models often have been calibrated by trial and error and with little understanding of model sensitivity to the various parameters. Methodologies for estimating best fit values of the washoff parameters...

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)...

A preliminary test of biogeochemical exploration for locating uranium occurrences in the Marfa Basin, Texas, was conducted in 1978. Only 6 of 74 plant samples (mostly catclaw mimosa, Mimosa biuncifera) contained uranium in amounts above the detection limit (0.4 ppm in the ash) of the conventional fluorometric method. The samples were...

Frequent surveys of seven trilateration networks in southern California over the interval 1973–1980 suggest that a regional increment in strain may have occurred in 1978–1979. Prior to 1978 and after late 1979 the strain accumulation has been predominantly a uniaxial north-south compression. This secular trend was interrupted sometime in 1978–1979...

Emerged Pliocene and Pleistocene shorelines and associated marine deposits were used to determine the magnitude and rate of vertical crustal movement during the past 3 m.y. in the United States Atlantic Coastal Plain of South and North Carolina. On the basis of a...

Water samples with specific conductances ranging from 66 to 6950 ??mho/cm at 25 ??C were analyzed for ammonia-N (NH3-N), nitrate plus nitrite-N (NO3 + NO2-N), nitrite-N (NO2-N), and phosphate-P (PO4-P) by using both a "segmented-flow" analyzer and a "discrete" analyzer. Plots of the discrete vs. the segmented-flow results showed linear...

The geology beneath Lake Michigan between 43°00' and 44°00' N and between 86°30' and 87°40' W is interpreted from a synthesis of 1,700 km of continuous seismic reflection profile data, bathymetry, grab samples, and onshore surface and subsurface information.The continuous seismic reflection profiles and bathymetry provided information for maps of...

The need for interdisciplinary research on resource appraisal techniques was recognized by Samuel G. Lasky, a U.S. Geological Survey geologist, more than 30 years ago. His efforts to devise an appraisal technique that incorporated many attributes of mineral resources resulted in a cumulative tonnage-grade relationship that has been referred to...

A positive magnetic anomaly extends discontinuously from the south side of the Copper River basin, along the southeast side of Cook Inlet and Shelikof Strait, and southwestward from Kodiak Island to near Sutwik Island. Regionally, this anomaly parallels the Border Ranges fault and...

Vitrinite reflectance measured in immersion oil (Ro) on kerogen extracted from hydrothermally altered mudstones in borehole M-84 at the Cerro Prieto geothermal field exhibit an increase in mean reflectance (Ro">Ro) from 0.12 per cent at 0.24 km depth to 4.1 per cent at 1.7...

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...

A liquid chromatography-atomic absorption spectrometry (LC-AAS) hybrid analytical technique is presented for metal speciation measurements on complex liquid samples. The versatility and inherent metal selectivity of the technique are Illustrated by the rapid determination of five tetraalkyllead compounds in commercial gasoline. Separation of the individual tetraalkyllead species is achieved by...