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Levels of estradiol, progesterone, and testosterone were determined in plasma of sea lamprey (Petromyzon marinus) undergoing certain behaviors associated with spawning in natural and artifical stream environments. Significantly higher levels of estradiol, progesterone, and testosterone were found in males than in females. In the artifical spawning channel, levels of estradiol...

Alkylbenzenesulfonate surfactants were determined in groundwater at concentrations as low as 0.3 mg/L. The method uses XAD-8 resin for concentration, followed by elution with methanol, separation of anionic and nonionic surfactants by anion exchange, quantitation by titration, and identification by 13C nuclear magnetic resonance spectrometry. Laboratory standards and field samples...

Neutron-induced borehole gamma-ray spectroscopy has been widely used as a geophysical exploration technique by the petroleum industry, but its use for mineral exploration is not as common. Nuclear methods can be applied to mineral exploration, for determining stratigraphy and bed correlations, for mapping ore deposits, and for studying mineral concentration...

Tourmaline (dravite) from a layered two-plagioclase anorthosite in the Boehls Butte quadrangle, Idaho, has the following structural formula: (Na0.55Ca0.17)0.72(Mg1.96Fe0.57Mn0.01Ti0.04V0.03Al0.47)3.08Al6(BO3)3.02Si5.98O18(OH,F)3.35. The indices of refraction are ω = 1.647(1) and ε = 1.621(1), and the unit cell parameters are a = 15.9425(6) and c = 7.1883(3)....

A map shows generalized contours of the altitude of water levels for wells completed in the Sparta-Memphis aquifer in eastern Arkansas. Most water-level measurements used in constructing the map were from the spring of 1980, but supplemental measurements from other years indicated no long-term change in water levels. Hydrographs for...

Channel modifications from 1968 to 1969 on the South Fork Forked Deer River in western Tennessee have caused upstream degradation, downstream aggradation, and bank failures along the altered channels, adjacent reaches, and tributaries. The result of these adjustments is a general decrease in gradient as the channel attempts to absorb...

No abstract available....

Government regulations on health, safety and environment have been poppular blamed for the declining productivity in U.S. coal mines since 1970. The stagnation in the coal industry east of the Mississippi is alleged to have been caused by this declining productivity...

The effects of three methods of data selection upon the assumed main field levels for geomagnetic observatory records used in main field modeling were investigated for a year of very low solar-terrestrial activity. The first method concerned the differences between the year's average of quiet day field values and the...

In many coastal plain estuaries light attenuation by suspended sediments confines the photic zone to a small fraction of the water column, such that light limitation is a major control on phytoplankon production and turnover rate. For a variety of estuarine systems (e.g. San Francisco Bay, Puget Sound, Delaware Bay,...

Large-scale gravitational spreading of steep-sided ridges characterized by linear fissures, trenches, and uphill-facing scarps high on the sides and tops of ridges are known worldwide. Such spreading, termed sackung, is commonly attributed to pervasive plastic deformation of a rock mass, and is here analyzed as such. Beginning with a previously...

There was one major earthquake (7.0-7.9) during this reporting period in Taiwan, a magnitude 7.8, which caused deaths and consideralbe damage. Earthquake-related deaths were reported in Bulgaria and in a mine in Poland. There was no significant earthquakes in the United States. ...

In many areas of the world, landslides dams are both interesting natural phenomena and significant hazards. A few of the these natural blockages attain heights that rival or exceed those of the largest manmade dams. A landslide dam in its natural state differs from a constructed embankment dam in that...

There were two major earthquakes during the last two months of the year, both in the Gulf of Alaska. Earthquake-related deaths were reported from Mexico, Japan and Indonesia.  Southern California was hit by two strong earthquakes; both caused damage and some injuries. ...

The purpose of this investigation was to describe the water table configuration and its temporal variations, estimate aquifer properties, and evaluate the interaction of groundwater and surface water in the inner valley of the Rio Grande in southern Albuquerque, New Mexico, where groundwater contamination is a continuing concern. The upper...

There were two major earthquakes (7.0-7.9) during the first two months of the year. The first, on January 30 in the South Sandwich Islands region, was in an unpopulated area; the second was on February 8 in New Guinea. In the United States the largest earthquake during this reporting period was...

The amount of pyrite (FeS2) removed by physical cleaning varies with differences in the amount of pyrite enclosed within minerals and of free pyrite in feed coals. A microscopic procedure for characterizing the size and maceral association of pyrite grains was developed and evaluate by testing three coals and their...

A combined Lu-Hf and U-Th-Pb isotopic study was made of 25 zircons and 2 whole rocks from the late Archean crust (2,888-2,668 Ma) in the southern Superior Province, Canada. The relative abundances of U, Th, Lu and Hf in zircons from the low grade Michipicoten and Gamitagama greenstone belts show...

Particle displacements from incident plane waves at the wall of a fluid-filled borehole are formulated by applying the seismic reciprocity theorem to far-field displacement fields. Such displacement fields are due to point forces acting on a fluid-filled borehole under the assumption of long wavelengths. The displacement fields are analyzed to...

Intensity distortions and poor signal to noise in the cross-polarization magic-angle sample spinning NMR of fulvic acids were investigated and attributed to molecular mobility in these ostensibly "solid" materials. We have shown that inefficiencies in cross polarization can be overcome by lowering the sample temperature to about -60??C. These difficulties...

Classification of Quaternary dating methods should be based on the level of quantitative information and the degree of confidence contained in the age estimates produced by the dating methods. We recommend the use of the terms numerical-age, calibrated-age, relative-age, and correlated-age to describe these levels. We also classify dating methods...

This paper examines the relative importance, in terms of a deposit's commercial status, of physical characteristics of onshore titanium-bearing heavy-mineral placer deposits, and applies these findings to the search for and evaluation of offshore deposits. Results obtained by applying statistical discriminant analysis show that the characteristics most useful for predicting...

The distribution of fracture permeability in granitic rocks was investigated by measuring the distribution of vertical flow in boreholes during periods of steady pumping. Pumping tests were conducted at two sites chosen to provide examples of moderately fractured rocks near Mirror Lake, New Hampshire and intensely fractured rocks near Oracle,...

The relative contribution of different components to the attenuation of photosynthetically active radiation was determined in the Charlotte Harbor estuarine system based on laboratory and in situ measurements. Agreement between laboratory and in situ measurements of the attenuation coefficient (kt) was good (r2 = 0·92). For all in situ measurements (n = 100), suspended, non-chlorophyll matter accounted...