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Page 5825, results 145601 - 145625

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Mazama ash in the Northeastern Pacific
C.H. Nelson, L.D. Kulm, P.R. Carlson, J. R. Duncan
1968, Science (161) 47-49
Volcanic glass in marine sediments off Oregon and Washington correlates with continental deposits of Mount Mazama ash by stratigraphic position, refractive index, and radiocarbon dating. Ash deposited in the abyssal regions by turbidity currents is used for tracing of the dispersal routes of postglacial sediments and for evaluation of marine...
Diatremes with kimberlitic affinities in North-Central Montana
B. C. Hearn Jr.
1968, Science (159) 622-625
Diatremes in the Missouri River Breaks demonstrate systematic subsidence-ring structure, contain inclusions derived from far above and far below, and have been produced by gas-rich eruptions of alkalic ultramafic magmas. Similar magmas have produced diatremes in many localities in the world and are known to be closely associated with and...
Mineralogy as a function of depth in the prehistoric Makaopuhi tholeiitic lava lake, Hawaii
B.W. Evans, J.G. Moore
1968, Contributions to Mineralogy and Petrology (17) 85-115
The electron probe X-ray microanalyzer has been used to determine the compositional variability of the groundmass minerals and glass in 10 specimens from a complete 225-foot section of the prehistoric tholeiitic lava lake of Makaopuhi Crater, Hawaii. The order of beginning of crystallization was: (1) chromite, (2) olivine, (3) augite,...
Studies in the system MgO-SiO2-CO2-H2O(I): The activity-product constant of chrysotile
P. B. Hostetler, C. L. Christ
1968, Geochimica et Cosmochimica Acta (32) 485-497
Chrysotile dissolves congruently in water according to the reaction: Mg3Si2O6(OH)4c + 5H2Ol = 3Mgaq2+ + 6OHaq− + 2H4SiO4aq. Experimental determination of the activity-product constant of chrysotile, Kchr = [Mg2+]3[OH−]6[H4SiO4aq]2, at 90°C, yields the value of Kchr = 10−49.2 ± 100.5. A synthetic sample and a natural sample from New Idria, California, were used in the determination.Values of Kchr were calculated for temperatures...
Structural charge site influence on the interlayer hydration of expandable three-sheet clay minerals
Raymond L. Kerns Jr., Charles J. Mankin
1968, Clays and Clay Minerals (16) 73-81
Previous investigations have demonstrated the influences of interlayer cation composition, relative humidity, temperature, and magnitude of interlayer surface charge on the interlayer hydration of montmorillonites and vermiculites. It has been suggested that the sites of layer charge deficiencies may also have an influence upon the amount of hydration that can...
Exsolution in clinoamphiboles
M. Ross, J. J. Papike, P.W. Weiblen
1968, Science (159) 1099-1102
Ten amphibole specimens from a variety of metamorphic rocks such as talc schists, eclogites, and metamorphosed iron formations contain lamellae of a second amphibole oriented parallel to (101) or (100), or both, of the host. Tremolites, actinolites, and hornblendes commonly have lamellae of a calcium-poor clinoamphibole with P21/m space-group symmetry,...
Hydration rind dates rhyolite flows
I. Friedman
1968, Science (159) 878-880
Hydration of obsidian has been used to date rhyolite flows, containing obsidian or porphyritic glass, at Glass Mountain (Medicine Lake Highlands) and Mono Lake, California. The method is simple and rapid and can be used to date flows that erupted between 200 and approximately 200,000 years ago....
Measurement of geothermal flux through poorly consolidated sediments
J.H. Sass, R. J. Munroe, A.H. Lachenbruch
1968, Earth and Planetary Science Letters (4) 293-298
In many regions, crystalline rocks are covered by hundreds of meters of unconsolidated and poorly consolidated sediments. Estimates of heat flux within these sediments using standard continental techniques (temperature and conductivity measurements at intervals of 10 to 30 meters) are unreliable, mainly...
Geology and ground-water resources of Fillmore County, Nebraska, with a section on chemical quality of the water
Charles Franklin Keech, V. H. Dreeszen, L. R. Petri
1968, Water Supply Paper 1839-L
Fillmore County, an area 24 miles square, lies in the eastern part of the Nebraska loess plain. Although tributaries of the Big Blue River have eroded valleys into this plain, much of the original surface is intact. Broad flats and numerous shallow undrained depressions characterize the plain. The county is...
A preliminary report of a recently discovered aquifer at Sioux Falls, South Dakota
Kenneth D. Vaughan, Earl A. Ackroyd
1968, South Dakota Academy of Science Proceedings (47) 68-74
A hydrologic study of the Big Sioux aquifer system was begun July 1, 1966, by the U.S. Geological Survey, in cooperation with the City of Sioux Falls and the East Dakota Conservancy Sub-District.   Test drilling being done in the search for a southern outlet to the Big Sioux aquifer has...
Some enzymatic properties of brain Acetylcholinesterase from bluegill and channel catfish
James W. Hogan, Charles O. Knowles
1968, Journal of the Fisheries Research Board of Canada (25) 615-623
Using a manometric technique an acetylcholinesterase (EC 3.1.1.7, acetylcholine acetyl-hydrolase) was demonstrated in brain tissue from the bluegill, Lepomis macrochirus Rafinesque, and the channel catfish, Ictalurus punctatus (Walbaum). The activities were 19 and 37 μmoles acetylcholine hydrolyzed/milligram protein per hour for the bluegill and channel catfish enzymes, respectively. The optimum substrate concentration for the hydrolysis...
Some effects of mirex on two warm-water fishes
Charles C. Van Valin, Austin K. Andrews, Lafayette L. Eller
1968, Transactions of the American Fisheries Society (97) 185-196
The effects of mirex on two species of warm-water fishes were studied in three experiments in which the fish were exposed either by feeding a mirex-treated diet, or by treating the holding ponds with a mirex formulation. Bluegills were used in the feeding experiment, where three different levels of mirex...
Electrophoretic separation of fish brain esterases
Charles O. Knowles, Suresh K. Arurkar, James W. Hogan
1968, Journal of the Fisheries Research Board of Canada (25) 1517-1519
Fish brains were homogenized in an all-glass Potter-Elvehjem-type tissue grinder in 40% sucrose solution. The homogenate concentration was 10 brains/ml for both the bluegill and channel catfish. The brei was centrifuged at 34,700 g for 30 min at 5 C, and 30 J.lliters of the supernatant were used per column...
Maps showing locations of surface water stations: catalog of information on water data
1968, Report
United States Bureau of the Budget Circular A-67, issued in 1964, calls upon the Department of the Interior to coordinate certain water-data-acquisition activities by Federal agencies. The Circular contains guidelines for coordinating Federal water-data collection from streams, lakes, reservoirs, estuaries, and ground water; it also contains guidelines for developing a...
Hydrologic and climatologic data, 1967, Salt Lake County, Utah
A. G. Hely, Reed W. Mower, C. A. Horr
1968, Utah Basic-Data Release 15
An investigation of the water resources of Salt Lake County, Utah, was undertaken by the Water Resources Division of the U.S. Geological Survey in July 1963. This investigation is a cooperative project financed chiefly by equal contributions of the State of Utah and the Federal Government in accordance with an...
Selected hydrologic data, San Pitch River drainage basin, Utah
G.B. Robinson
1968, Utah Basic-Data Release 14
The u.s. Geological Survey investigated the ground-water resources of the San Pitch River drainage basin during the period 1964- 67. The investigation was a cooperative project, financed equally by the Utah Department of Natural Resources, Division of Water Rights, and the Federal Government, and was a part of an investigation...
Design and construction of a dual recharge system at Minot, North Dakota
Wayne A. Pettyjohn
1968, Groundwater (6) 4-8
In 1965, a ground-water recharge facility was constructed and placed in operation to forestall an impending water shortage at Minot, North Dakota. The facility is unique in that the rate of recharge to a buried sand and gravel aquifer is augmented by perforating an overlying bed of clay using hydraulic...