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A steel capillary gas chromatographic system, based on the Hewlett-Packard (HP) Model 5711A gas chromatograph and HP model 3354A laboratory data system, was converted to an automated glass capillary system suitable for routine quantitative analysis of trace levels of hydrocarbons. Two instrument modifications, which were required for a fully automated...

Comparisons of the karyotypes of the species of Vampyressa suggest two modes of chromosomal rearrangements in the derivation of the Vampyressa karyotypes: pericentric inversions in V. brocki, V. nymphaea, and V. bidens; and translocations (fusions) in V. melissa and the variants of V. pusilla. This Vampyressa phylogenetic model was used to evaluate the possible derivations of the chromosomal patterns of...

Twenty-two female big brown bats (Eptesicus fuscus) were collected in a house attic in Montgomery County, Maryland. Seventeen were fed mealworms (Tenebrio molitor larvae) that contained 166 ppm DDE; the other five were fed uncontaminated mealworms. After 54 days of feeding, six dosed bats were frozen and the remaining 16...

Dating of some small plutons in the San Gabriel and Chocolate Mountains, southern California, yields Miocene K-Ar ages. A single granodiorite pluton that has been segmented by branches of the San Jacinto fault intrudes the Pelona Schist and yields ages of 14.0 to 18.6 million years. Several quartz monzonite plutons...

Construction of the Tennessee-Tombigbee Waterway in northeast Mississippi will involve dewatering as much as 46 m of an unconfined aquifer near the Tennessee Valley divide. Dewatering by trenching is one of the proposed methods. Methods of calculating effects of dewatering by trenching have been heretofore limited to situations where ideal...

A modified LEGO WR-12 carbon determinator is used in a combustimetric determination of total carbon in geologic materials. A thermal conductivity cell is used as the sensing device. International reference samples are analyzed and compared to results previously published. Three new standards from the Canadian Certified Reference Materials Project were...

A new model is proposed for the structure of humic acids. In this model humic acid is pictured as being made up of a hierarchy of structural elements. At the lowest level in this hierarchy are simple phenolic, quinoid, and benzene carboxylic acid groups. These groups are bonded covalently into...

The relatively high seismicity of the San Andreas fault zone in central California provides an excellent opportunity to search for seismic forerunners to moderate earthquakes. Analysis of seismic traveltime and earthquake location data has resulted in the identification of two possible seismic forerunners. The first is a period of apparently...

Fatty acids isolated in sedimentary black barite (BaSO4) from Arkansas and Nevada were identified by gas chromatography-mass spectroscopy. The dominant or major fatty acids found in these beds of barite are C16:0, C18:0, and C18:1. The occurrence and distribution of these acids in this type of rock may serve as...

Fault-creep events measured on the San Andreas and related faults near Hollister, California, can be described by a rheological model consisting of a spring, power-law dashpotand sliding block connected in series. An empirical creep-event law, derived from many creep-event records analyzed within the constraints of the model, provides a remarkably...

Precambrian quartz dolerites and metadolerites of the central Bighorn Mountains form dikes that intrude a Precambrian metamorphic and igneous terrane typical of the Laramide uplifts of the middle Rocky Mountains. They have a restricted range of major- and trace-element compositions and are typical of basalts in the middle stages of...

Eggs stripped from lake whitefish (Coregonus clupeaformis) spawning in Lake Michigan were incubated in the laboratory at temperatures similar to those on whitefish spawning grounds in Lake Michigan during December-April. Observed times from fertilization to attainment of each of 21 developmental stages were used to test a model that predicts...

Landfills operated by the towns of Babylon and Islip in southwest and central Suffolk County, N.Y., contain urban refuse , incinerated garbage, and scavenger (cesspool) waste; some industrial refuse is deposited at the Babylon site. The Islip landfill was started in 1933, the Babylon landfill in 1947. The landfills are...

No abstract available....

The proposed Great Bear wilderness has a good potential for oil and gas (mainly gas), and a moderate potential for submarginal resources of copper and silver in a belt 25 miles (40 km) long and about 1 mile (1.6 km) wide that is partly within the study area along the...

Lajas Valley is plagued with salinity and waterlogging problems of the soils. Use of brackish (500 milligrams per liter) ground water for irrigation compounded the problem until an irrigation-drainage system was constructed in 1955. Lajas Valley is an alluvium-filled trough between volcanic and limestone highlands. The alluvium, mostly clay and...

Exploration models for podiform chromite in the Medford-Coos Bay quadrangles must consider the facts that (1) one deposit occurs for every 5 km 2 of ultramafic outcrop; similarly for a 5 km 3 volume, and (2) the average deposit has a tonnage of 206 tonnes, a volume of 8.9 m...

An anomaly about 300 gammas in amplitude has been observed in data from an aerial magnetic survey flown over parts of Duval, Live Oak, McMullen, and Webb Counties, Tex. A two-and-one-half-dimensional model was used to iterpret the data, and the anomaly is apparently caused by a large mafic body centered...

Field studies and digital modeling of a lava rock aquifer system near Kahului, Maui, Hawaii, were employed to define and describe the distribution of planned injected wastewater from a secondary treatment facility. The lava rock aquifer contains water that is almost as saline as seawater. The saline water is below...

In the course of modernizing the low-speed-tape-recorder portable seismic systems and considering the possibilities for the design of a cassette-tape-recorder seismic refraction system, the factors that limit the sensitivity and dynamic range of such systems have been reviewed. These factors will first be stated briefly, and then their influence on...

Regional decline of aquifer head due to ground-water withdrawal in the Houston area has caused extensive land-surface subsidence. The NASA-Johnson Space Center (NASA-JSC) in southeastern Harris County, Texas, was about 13 to 19 feet above mean sea level in 1974 and sinking at a rate of more than 0.2 foot...

Long-term flood records for small basins, especially those basins of less than 10 square miles, are almost nonexistent in Florida. In July 1967 a program was begun to develop a data base to extend short-term flood-peak records for small basins by use of the U.S. Geological Survey rainfall/runoff model. Concurrent...