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Page 6483, results 162051 - 162075

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Publication Extents

Not all publications have extents, not all extents are completely accurate
A demographic analysis of continuously irradiated and nonirradiated populations of the lizard, Uta stansburiana
F.B. Turner, P.A. Medica, J.R. Lannom Jr., G.A. Hoddenbach
1969, Radiation Research (38) 349-356
A natural population of the lizard Uta stansburiana occupying a fenced 20-acre area in southern Nevada has been exposed to essentially continuous gamma irradiation since February 1964. Tissue doses averaged about 2 rads/day. Nonirradiated populations occupying three adjoining 20-acre areas have also been investigated. Five years of sampling data drawn...
Willamette Basin Comprehensive Study of Water and Related Land Resources: Appendix B--Hydrology
Willamette Basin Task Force
1969, Report, Willamette Basin comprehensive study of water and related land resources
The study was undertaken to plan for the proper development of water andrelated land resources of the Willamette Basin in Oregon. Appendix B, along with Appendices A and C, provides supporting data for the functional Appendices D through L. Climate is first discussed, including the climatic significance of geographical features such as the...
Cycads: Fossil evidence of late Paleozoic origin
S.H. Mamay
1969, Science (164) 295-296
Plant fossils from Lower Permian strata of the southwestern United States have been interpreted as cycadalean megasporophylls. They are evidently descended from spermopterid elements of the Pennsylvanian Taeniopteris complex; thus the known fossil history of the cycads is extended from the Late Triassic into the late Paleozoic. Possible implications...
Ellsworth Mountains: Position in West Antarctica due to sea-floor spreading
J. M. Schopf
1969, Science (164) 63-66
Similarities of middle and upper Paleozoic deposits of the Ellsworth Mountains with those of the Pensacola, Horlick, and other Transantarctic mountains indicate that all these ranges may have had a related geologic history. A tentative explanation is now suggested which involves sea-floor spreading and translocation of the...
Massive sulfide deposits and volcanism
Charles A. Anderson
1969, Economic Geology (64) 129-146
Massive sulfide deposits, consisting of pyrite and/or pyrrhotite and various ratios of chalcopyrite, sphalerite, and galena, are commonly associated with volcanic rocks that accumulated in eugeosynclines. Later deformation may leave an imprint of regional metamorphism. Two-thirds of the deposits mentioned in this review are about equally divided between silicic and...
Unstable sulfur compounds and the origin of roll-type uranium deposits
H.C. Granger, C. G. Warren
1969, Economic Geology (64) 160-171
Anomalous concentrations of iron sulfides found at roll fronts are believed to result from limited oxidation and mobilization of reduced sulfur species from earlier formed pyrite within the more extensively oxidized core of the roll. Laboratory experiments and chemical theory suggest that the reactions need not be biogenic, and that...
Water analysis
Marvin J. Fishman, B.P. Robinson
1969, Analytical Chemistry (41) 323-360
No abstract available....
Adoption of a nestling house mouse by a female short-tailed shrew
Lawrence J. Blus, D.A. Johnson
1969, American Midland Naturalist (81) 583-584
A nursing female short-tailed shrew (Blarina brevicauda) adopted a nestling house mouse (Mus musculus). The mouse was observed in the nest with the female and her litter of shrews three days after it was introduced into the aluminum box containing the shrews,...
Rate of sulfuric acid formation in Yellowstone National Park
Robert Schoen
1969, Geological Society of America Bulletin (80) 643-650
Sulfuric acid forms near sulfurous hot springs as the result of oxidation of hydrogen sulfide exhalations by atmospheric oxygen. This strong acid rapidly alters the surrounding rocks and can destroy man-made structures and contaminate streams. Four tracts of acid-altered ground in Yellowstone National Park were studied in order to determine...
Bacteria in blood and kidney of apparently healthy hatchery trout
G. L. Bullock, S. F. Snieszko
1969, Transactions of the American Fisheries Society (98) 268-271
Aseptic examination of blood and kidney material from three species of apparently healthy trout at two hatcheries showed that 12.5% of examined trout at one hatchery and 26.1% of trout at the other carried low numbers of bacteria. In addition, sera from these trout had agglutinins against some of the...
New thrusts in ground water
C. L. McGuinness
1969, Groundwater (7) 7-10
Four principal trends in ground water are apparent:(1) Increasing use of ground water for domestic supplies. Geohydrologists must learn to quantitatively evaluate the supply under conditions of maximum development, not merely determine the availability of a supply that does not strain the aquifer. (2) Aquifers will be looked to increasingly...
Lead and strontium isotopes in volcanic rocks from northern Honshu, Japan
Carl E. Hedge, Roy J. Knight
1969, Geochemical Journal (3) 15-24
Isotopic compositions of lead and strontium and concentrations of lead, uranium, thorium, rubidium, and strontium were measured in a suite of volcanic rocks, ranging from basalt to rhyodacite in composition, and in granite and gabbro xenoliths from a traverse across northern Honshu. The observed 238U/204Pb (μ) ratio ranges from 2.4 in...
Lower Llandovery of the northern Appalachians and adjacent regions
William G. Ayrton, William B. N. Berry, Arthur J. Boucot, Jean Lajoie, Pierre J. Lesperance, Louis Pavlides, W. Brian Skidmore
1969, Geological Society of America Bulletin (80) 459-483
Rocks of clearly dated early Llandovery age, as well as rocks that can logically be classed as early Llandovery from their regional relationships, appear to be more widespread than recognized, heretofore, in the northern Appalachians and adjacent regions. Their areal distribution and lithology permit a generalized reconstruction of the paleogeography,...
Heat flow in the Arctic
Arthur H. Lachenbruch, B. Vaughan Marshall
1969, Arctic (22) 300-311
Defines heat flow as the flux at the earth's solid surface of heat conducted from the interior; the heat-flow-unit (hfu) is on the order of 1-millionth calorie through each sq cm of the surface/sec, which is enough to melt a 4-mm layer of ice over the earth's surface/yr. Earth heat...
Active metamorphism of upper Cenozoic sediments in the Salton Sea geothermal field and the Salton Trough, southeastern California
L.J. Patrick Muffler, Donald E. White
1969, Geological Society of America Bulletin (80) 157-181
The Salton Sea geothermal system is entirely within Pliocene and Quaternary sediments of the Colorado River delta at the north end of the Gulf of California. At the time of deposition, these sediments consisted of sands, silts, and clays of uniform original mineralogic composition, but under the elevated temperatures and...
Florida submergence curve revised: Its relation to coastal sedimentation rates
D.W. Scholl, F.C. Craighead Sr., M. Stuiver
1969, Science (163) 562-564
New data substantiate as well as modify the south Florida submergence curve, which indicates that eustatic sea level has risen continuously, although at a generally decreasing rate, during the last 6500 to 7000 sidereal years (5500 standard radiocarbon years) to reach its present position. Accumulation rates of coastal deposits are...
Coexisting amphiboles from blueschist facies metamorphic rocks
G. R. Himmelberg, J. J. Papike
1969, Journal of Petrology (10) 102-114
Four pairs of associated calcic and sodic amphiboles from blueschist facies metamorphic rocks were analyzed with the electron microprobe and studied by single-crystal X-ray diffraction techniques. Except for ranges in the ratios Mg/(Mg+Fe) and Fe3+/(Fe3++Al+Ti), the sodic amphiboles are similar in chemical composition. The amount of calcium in the M(4)-site...
A seismic-refraction survey of crustal structure in central Arizona
David H. Warren
1969, Geological Society of America Bulletin (80) 257-282
The U.S. Geological Survey conducted a seismic-refraction study of the earth's crust and upper mantle near the Tonto Forest Seismological Observatory (TFO), located 10miles south of the Mogollon Rim near Payson in central Arizona. Two recording lines 400 km long intersect in the approximate form of a cross at TFO;...
Experiments on formation of contorted structures in mud
Edwin D. McKee, Moshe Goldberg
1969, Geological Society of America Bulletin (80) 231-243
Contorted structures can be formed in mud or sand as a result of differential loading. Fifteen sets of experiments were conducted in water tanks to test various factors of possible significance in the contortion of mud by loading. Of six factors tested, the most significant was distribution of load, but...
Vertical density currents — II
W. H. Bradley
1969, Limnology and Oceanography (14) 1-3
Examples of vertical density currents wholly within the domain of laminar flow, one in a water solution, the other in air, have come to my attention. Both examples illustrate new ways of introducing and dispersing microscopic particles into static fluids and both demonstrate that a stable, clearly defined layer of...