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Publication Extents

Not all publications have extents, not all extents are completely accurate
Nationwide study of the streamflow data program
R. W. Carter, M. A. Benson
1971, Journal of the American Water Resources Association (7) 383-385
During 1970 the Geological Survey conducted a study to evaluate the surface-water data collection program. Objectives were formulated, specific goals were set, a massive analysis of available data was made to determine the extent to which the present system enables the goals to be met, alternatives...
Petrologic and geophysical nature of serpentinites
Robert G. Coleman
1971, Bulletin of the Geological Society of America (82) 897-917
Mineralogically, serpentinites consist predominantly of lizardite, clinochrysotile, and antigorite. Recent work has shown that these minerals are not polymorphs. Chrysotile is the only mineral recognized as a synthetic product in experimental studies of the system MgO-SiO2-H2O. Antigorite seems to be stable at higher temperatures than lizardite or chrysotile. The density...
Correlation of uranium, thorium, and potassium with aeroradioaetivity in the Berea Area, Virginia
S.K. Neuschel, C. M. Bunker, C.A. Busa
1971, Economic Geology (66) 302-308
In the Berea area, a small quartz monzonite pluton intrudes chlorite-actinolite schist and is overlapped by Coastal Plain sand and gravel deposits. A detailed aeroradioactivity survey of the area shows unusually high radioactivity (1,150 counts per second) over the quartz monzonite. A total of 22 auger samples was taken across...
Elevation-relief ratio, hypsometric integral, and geomorphic area-altitude analysis
Richard J. Pike, Stephen E. Wilson
1971, Bulletin of the Geological Society of America (82) 1079-1083
Mathematical proof establishes identity of hypsometric integral and elevation-relief ratio, two quantitative topographic descriptors developed independently of one another for entirely different purposes. Operationally, values of both measures are in excellent agreement for arbitrarily bounded topographic samples, as well as for low-order fluvial watersheds. By...
Gold content of natural waters in Colorado
Arthur W. Gosling, E. A. Jenne, T. T. Chao
1971, Economic Geology (66) 309-313
Neutron activation analysis of 67 samples of water draining from gold-barren and gold-enriched sedimentary, igneous, and metamorphic rocks of the Colorado Front Range reveals a relatively small range in total gold content (nondetectable to 150 nanograms per liter). "Solute" gold concentrations were generally higher than...
Sierra Nevada plutonic cycle: Part I, origin of composite granitic batholiths
R. W. Kistler, J. F. Evernden, H. R. Shaw
1971, Bulletin of the Geological Society of America (82) 853-868
Intrusion of Mesozoic batholiths in California and the western North America Cordillera began in the Late Triassic 210 m.y. ago and ended in the Late Cretaceous 80 m.y. ago. Emplacement of granitic rocks was apparently not continuous but was accomplished during five major epochs of...
Sierra Nevada plutonic cycle: Part II, tidal energy and a hypothesis for orogenic-epeirogenic periodicities
H. R. Shaw, R. W. Kistler, J. F. Evernden
1971, Bulletin of the Geological Society of America (82) 869-895
The dissipative power of the solid earth tides is the order of 1019 ergs/sec, or a few percent of terrestrial heat flow. It is proposed that this energy is concentrated along oceanic ridge systems and in the asthenosphere by mechanisms of viscous dissipation involving shear melting....
Sedimentary and gravity-slide emplacement of serpentinite
J. P. Lockwood
1971, Bulletin of the Geological Society of America (82) 919-936
Large deposits of serpentinite in alpine-type orogenic areas have been formed by sedimentary processes ranging from the detrital accumulation of bedded serpentinite sandstone and shale to the emplacement of chaotic breccias (olistostromes) and gigantic slide blocks. Known occurrences of sedimentary serpentinite are listed, and eight deposits from the circum-Pacific, Caribbean,...
Thrust and strike-slip faulting in the Plomosa Mountains, southwestern Arizona
F. K. Miller, Edwin H. McKee
1971, Bulletin of the Geological Society of America (82) 717-722
Thrust and strike-slip faulting are recognized in the Plomosa Mountains, southwestern Arizona. The distribution of rock types and the geometry of the thrust faults necessitate that the upper plate moved from east to west. The amount of displacement is not known, but is considered to...
Nomenclature and correlation of some upper Precambrian and basal Cambrian sequences in western Utah and southeastern Idaho
Max D. Crittenden Jr., Frederick E. Schaeffer, D. E. Trimble, Lee A. Woodward
1971, Bulletin of the Geological Society of America (82) 581-602
Recent stratigraphic studies in three widely separated localities in southeastern Idaho and western Utah have revealed a startling continuity of both individual rock units and of rock sequences over a distance of some 300 mi parallel to the strike of a late Precambrian and Cambrian depositional trough. Between 15,000 and...
A further revision of the stratigraphic nomenclature of the Wissahickon Formation in Maryland
Michael W. Higgins, George Wescott Fisher
1971, Bulletin of the Geological Society of America (82) 769-774
The Wissahickon Formation, the thickest and most extensive unit of the Glenarm Series, was divided into lithofacies several years ago. We suggest revision of two of these lithofacies and addition of another. We also suggest that the term lithofacies be shortened to facies. The added...
The functional significance of movements and positions of the pinnae of the African Elephant, Loxodonta africana
I.O. Buss, James A. Estes
1971, Journal of Mammalogy (52) 21-27
Observations of wild African elephants (Loxodonta africana) in Uganda indicated that flapping and spreading the highly vascularized ears are probably important functions for heat dissipation. Ear flapping increased as ambient temperatures rose and decreased or ceased during cold or rainy weather. Rate of ear flapping was inversely related to wind...
Deformation of lee-side laminae in eolian dunes
Edwin D. McKee, John R. Douglass, Suzanne Rittenhouse
1971, Bulletin of the Geological Society of America (82) 359-378
Processes responsible for structures in sand dunes consist of (l) primary deposition by saltation and creep and by settling from suspension, (2) redeposition accompanying avalanching, and (3) penecontemporaneous erosion. Characteristics of dune structures were examined in the field by introducing marker beds of magnetite at times of sand deposition, thus...
Related strontium isotopic and chemical variations in oceanic basalts
Zell E. Peterman, Carl E. Hedge
1971, Bulletin of the Geological Society of America (82) 493-499
Sr87/Sr86 values in oceanic basalts range from 0.7012 to 0.7057 and correlate with basalt composition as measured by the ratio K2O/(Na2O + K2O). The distribution of data points on this plot can be approximated by the following ranges in Sr87/Sr86 and K2O/(K2O + Na2O) respectively: (l) ocean...