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One to three whole-rock samples from each of more than a dozen discrete plutonic intrusions in the east-central Sierra Nevada batholith have been analyzed for Sr87/Sr86 and Rb/Sr ratios to obtain information on initial Sr87 abundances.The initial Sr87/Sr86 ratios in the rock magmas forming this province appear to have been in the range...

A Yashica Sequelle camera was modified and equipped with a timing device so that it would take pictures automatically at 15-minute intervals. Several of these cameras were used to photograph randomly selected quadrats located in different marsh habitats. The number of birds photographed in the different areas was used as...

Shallow aquifers, commonly the most important sources of ground water, are also those most susceptible to contamination. The mode of entry of contaminants to shallow aquifers is (1) directly, via wells or secondary openings in consolidated rocks, (2) percolation through the zone of aeration, (3) induced infiltration through the zone of saturation, and (4) interaquifer leakage...

Naturally occurring stable or radioactive isotopes may be used in some places to identify the origin of saline water that contaminates some coastal aquifers. In a recent study to determine the origin of saline water in the Ocala Limestone aquifer near Brunswick, Georgia, the following sources were analyzed for C14 and...

After an examination of trends in the modeling of hydrologic systems, a review of some recent studies is given. The authors' preliminary studies on the feasibility and efficiency of the automatic evaluation of catchment model parameters by use of a digital computer are described and some results presented....

More than 100 independent isotopic ages have been determined for minerals from an area in northern Michigan about 35 miles square. Granites, pegmatites, and metamorphosed sedimentary and volcanic rocks have yielded Rb-Sr ages for feldspar, muscovite, and biotite, K-Ar ages for hornblende, muscovite, biotite, and feldspar, and U-Pb and Th-Pb ages for zircon. It was anticipated that we would learn from the measurements both...

The principal source of ground water throughout a large part of central and northeastern New Jersey is the aquifer in the Brunswick Shale -- the youngest unity of the Newark Group of Triassic Age. Large-diameter public-supply and industrial wells tapping the Brunswick Shale commonly yield several hundred gallons per...

The lower limit of abundance of sodium and potassium in ultramafic rocks is less than the threshold amount detectable by conventional analytical methods. By a dilutionaddition modification of the flame-spectrophotometric method, sodium and potassium have been determined in 40 specimens of alpine ultramafic...

Variational principles of anisotropic elasticity have been applied to aggregates of randomly oriented pure‐phase polycrystals having hexagonal symmetry and trigonal symmetry. The bounds of the effective elastic moduli obtained in this way show a considerable improvement over the bounds obtained by means of the Voigt and Reuss assumptions. The Hill average is found to be in...

Fresh ground water (200 parts per million total dissolved solids and upwards) occurs in portions of Pleistocene sandstone aquifers beneath basins and wadis in north Kuwait where the mean rainfall is about five inches per year. The fresh water is surrounded and underlain by brackish water (> 4000 ppm TDS)....

A modified Morey bomb was designed which contains a removable nichromecased 3.5-ml platinium crucible. This bomb is particularly useful for decompositions of refractory samples for micro- and semimicro-analysis. Temperatures of 400–450° and pressures estimated as great as 6000 p.s.i. were maintained in the bomb for...

Four dredge hauls from near the crest and from the eastern flank of the seismically active Mid-Indian Ocean Ridge at 23° to 24°S,...

The Vigil Network consists of places where observations are made through time to record changes in landscape features over a long period. Resurveys will usually be made once each year or every few years and the period of observation, hopefully, will extend through and beyond the International Hydrological Decade.Vigil Network...

English sole fillets previously equilibrated with aqueous 0.1% cysteine were dehydrated by three methods to moisture levels ranging from 2 to 72%. Model systems using cellulose to replace the fish tissue were also used. The samples were irradiated at 1 Mrad in an air, nitrogen, or oxygen atmosphere. The destruction...

Interpretation of a reversed seismic-refraction profile between Lake Mead, Nevada, and Mono Lake, California, indicates velocities of 6.15 km/sec for the upper layer of the crust, 7.10 km/sec for an intermediate layer, and 7.80 km/sec for the uppermost mantle. Phases interpreted to be reflections from the top of the intermediate...

The structure of the Earth’s crust (the outer shell of the earth above the M-discontinuity) has been intensively studied in many places by use of geophysical methods. The velocity of seismic compressional waves in the crust and in the upper mantle varies from place to place in the conterminous United...

The Swatara Creek of the Susquehanna River Basin is the farthest downstream sub-basin that drains acid water (pH of 4.5 or less) from anthracite coal mines. The Swatara Creek drainage area includes 567 square miles of parts of Schuylkill, Berks, Lebanon, and Dauphin Counties in Pennsylvania.To learn what environmental factors...

Field and petrographic studies of the Andover Granite and surrounding rocks have afforded an opportunity for an explanation of its emplacement and crystallization. The investigation has contributed secondarily to an understanding of the geologic history of southeastern New England, particularly as it is revealed in the Lawrence, Wilmington, South Groveland,...

A reconnaissance investigation of the sediment transported by selected Georgia streams during the period December 1957 to June 1959 was made to provide a general understanding of the physical quality of stream water in Georgia and to supply facts needed in planning more detailed work. The investigation was made by...

Ground-water supplies in the Dickson, Lawrenceburg, and Waverly areas are obtained from wells and springs in limestone and chert formations of Missisippian age. In the Dickson area most of the wells and springs are in Warsaw Limestone. In the Lawrenceburg and Waverly areas, ground-water supplies are obtained from Fort Payne...

Practically all the ground water of economic importance in the Truckee Meadows area, an alluviated intermontane basin in western Nevada is in the valley fill, which consists of unconsolidated and partially consolidated sedimentary deposits. The Mesozoic and Cenozoic consolidated rocks of the mountains bordering the valley contain some water in...

The magnetic properties of many substances first studied seriously by Faraday have played an important role in our modern technology. In particular, the magnetic properties of the transition elements are of great importance in the understanding of the electronic band form of these elements. Once the electronic band form is...

The public water supplies of the 100 largest cities in the United States (1960 U.S. Census) serve 9,650 million gallons of water per day (mgd) to 60 million people, which is 34 percent of the Nation's total population and 48 percent of the Nation's urban population. The amount of water...

This report describes the water resources of Genesee County, Mich., whose principal city is Flint. The sources of water available to the county are the Flint and Shiawassee Rivers and their tributaries, inland lakes, ground water, and Lake Huron. The withdrawal use of water in the county in 1958 amounted...