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Drag marks in the Upper Precambrian Winnall Beds of central Australia were made by semibuoyant flexible objects at least 15 centimeters long, which presumably were algae. This find extends the range of such marks into the Precambrian era and supplements the discovery of microflora in the same sedimentary sequence....

No abstract available....

Some immature mourning doves (Zenaidura macroura) are capable of breeding in their first (calendar) year of life. The breeding activities of immatures observed in this study included calling, copulating, and nesting. Development of sexual structures such as cloacal papillae, oviduct openings, and gonads was also regarded as evidence of breeding...

The tidal efficiencies of wells tapping the principal artesian aquifer in Glynn County, Georgia decrease with distance from the influencing tidal body and also decrease with well depth. Although the magnitude of water‐level fluctuation of these wells is largely dependent upon the distance to a large tidal body, the time of a high or a low water level in the wells is...

Data describing the shape and manner in which the cone of depression forms about a well discharging at a constant rate are used with various formulas to determine the hydraulic characteristics of aquifer materials. The solutions to these formulas generally are graphical and may be used to detect the presence of hydraulic or geologic...

The digital computer is used on a routine basis in the ground-water program in Kansas for tasks ranging from the listing of water-quality data in tabular and publishable form to statistically and graphically analyzing a mass of data.In the past year a number of computer programs in FORTRAN IV have...

A type‐curve method for determining anisotropy of unconfined aquifers, developed from electric analog simulation, is applied to drawdowns observed near, a well pumping from a glacial outwash aquifer at Piketon, Ohio. The coefficient of vertical permeability, P z'averaged 365 gpd per square foot. Computed drawdown for the pumped well, based on this value, differed by only a small amount from the observed drawdown. The coefficient...

Cohenite [(Fe, Ni)3C] is found almost exclusively in meteorites containing from 6 to 8 percent nickel (by weight). On the basis of iron-nickel-carbon phase diagrams at 1 atmosphere and of kinetic data, the occurrence of cohenite within this narrow composition range as a low-pressure metastable phase and the nonoccurrence of...

Three previous and five new records of the domestic sheep bot, Oestrus ovis, from the bighorn sheep are given. The life history and descriptions of adult and larval forms are presented. The significance of the occurrence of the parasite in the abnormal host is discussed....

Twelve magnetotelluric soundings were made along a 460-mile traverse in the southwestern United States. Spectral analysis of digitized graphic records was used to determine apparent resistivities and phase differences for periods in the range 10-1,000 sec. The geoelectric section to depths of the order of 300 km was found to...

A large part of our disquieting present-day pesticide problem is intimately tied to the freshwater ecosystem. Economic poisons are used in so many types of terrain to control so many kinds of organisms that almost all lakes and streams are likely to be contaminated. In addition to accidental contamination...

Branch County has abundant water resources throughout most of its area. Almost all the water used is supplied by wells that obtain water from glacial drift deposits and locally from fractures and sandy beds in the Coldwater Shale. Glacial drift in buried bedrock valleys may yield large quantities of water...

Recent paleomagnetic-radiometric data from six rhyolite domes in the Valles Caldera, New Mexico, indicate that the last change in polarity of the earth's magnetic field from reversed to normal (the Brunhes-Matuyama boundary) occurred at about 0.7 million years ago. A previously undiscovered geomagnetic polarity event, herein named the "Jaramillo normal...

A radiogenic tracer study has been made of lead and strontium in deep geothermal brines, salt from brine, and the upper Quaternary rhyolite domes near the Salton Sea in the Imperial Valley, California. The data on the brines and rhyolite glasses are compared to those from Quaternary Colorado River and Tertiary sediments of the area. The brines sampled contain '-'100 ppm Pb, sufficient for consideration as a...

Compared with the stratified deposits of iron minerals, those of manganese minerals have received little attention until recent years. Before 1930, students of the stratified deposits of manganese minerals have generally concluded that the contained manganese was derived from the decomposition of the rocks that formed the borders of the basins. Only in a few places have geologists recognized that if these...

Dechlorination of DDT to DDD in higher animals requires the presence of molecular oxygen, but in microorganisms the presence of oxygen hinders dechlorination. In cell-free preparations of Aerobacter aerogenes, the use of selected metabolic inhibitors indicated that reduced Fe(II) cytochrome oxidase was responsible for DDT dechlorination. This finding may possibly...

Band-reporting rates (the proportion of duck bands recovered by hunters that are actually reported to the Bird Banding Laboratory) appear to have decreased between the late 1950's and early 1960's. About one-half the banded ducks bagged during the 1958-59 and 1959-60 hunting seasons were reported-a rate similar to those recorded...

On the basis of recorded microrelief data, the continental margin between Cape Lookout, North Carolina, and the Bahama Islands may be divided into the following domains: (1) smooth - lacking any microrelief; (2) undulating - containing sand swells; (3) rough - characterized by numerous low, conical hills; and (4) blocky - broken by rectangular depressions. ...

No abstract available....

During February and March 1964, the U. S. Geological Survey ran caliper, conductance, and temperature logs on several wells in the Sarasota area. The Florida Geological Survey had previously run gamma ray and electric logs on the same wells. Two flowing wells were selected for packer testing. The two wells are about the same depth, penetrate essentially the same geologic horizons, and are about...

Nitrogen compounds in natural water are significant in public health, agriculture, industry, and geochemistry. The many sources of nitrogen compounds and the deep involvement of nitrogen in the life processes of organisms makes the study of such compounds difficult. The sources include natural aerosols, precipitation, fixation by micro‐organisms in soil...

Sedimentary iron and heavy-metal deposits of undetermined size have been found in the middle of the Red Sea some 2000 meters below the surface of the sea (Fig. 1). This discovery has been made from the Research Vessel Atlantis II, which is still at sea engaged in a series of oceanographic...

Aragonitic, unconsolidated sediments from the borings on the Eniwetok and Bikini atolls are isotopically identical with unaltered skeletal fragments, whereas the recrystallized limestones exhibit isotopic variations resulting from alteration in meteoric waters during periods of emergence. Dolomites and associated calcites are enriched in O18, perhaps because of interaction with hypersaline...

Small, vertically elongate concretionlike structures, here called rhizoconcretions, are found in scattered localities in and near the southern part of the Belted Range of Nye County, Nevada. The rhizoconcretions occur within a stratigraphically restricted zone in bedded vitric ash-fall tuff of late Tertiary age. The rhizoconcretions differ in mineralogy from their host rock in that they are cemented by a binder of undetermined composition, possibly a zeolite, whereas the host tuffs are...

No abstract available. ...