Isotopic composition of strontium in sea water throughout Phanerozoic time
Z. E. Peterman, C. E. Hedge, H. A. Tourtelot
1970, Geochimica et Cosmochimica Acta (34) 105-120
Isotopic analyses of strontium in primary fossil carbonate reveal significant variations in Sr87Sr86">Sr87Sr86 of sea water during the Phanerozoic. The strontium isotopic composition may have been uniform from the Ordovician through the Mississippian, with an average Sr87Sr86">Sr87Sr86 of 0.7078. A subsequent decrease...
Television experiment for Mariner Mars 1971
H. Masursky, R. Batson, W. Borgeson, M. Carr, J. McCauley, D. Milton, R. Wildey, D. Wilhelms, B. Murray, N. Horowitz, R. Leighton, R. Sharp, W. Thompson, G. Briggs, P. Chandeysson, E. Shipley, C. Sagan, J. Pollack, J. Lederberg, E. Levinthal, W. Hartmann, T. McCord, B. Smith, M. Davies, G. De Vaucouleurs, C. Leovy
1970, Icarus (12) 10-45
The Television Experiment objectives are to provide imaging data which will complement previously gathered data and extend our knowledge of Mars. The two types of investigations will be fixed-feature (for mapping) and variable-feature (for surface and atmospheric changes). Two cameras with a factor-of-ten difference in resolution will be used on...
Neutron radiative capture methods for surface elemental analysis
J.I. Trombka, F. Senftle, R. Schmadebeck
1970, Nuclear Instruments and Methods (87) 37-43
Both an accelerator and a 252Cf neutron source have been used to induce characteristic gamma radiation from extended soil samples. To demonstrate the method, measurements of the neutron-induced radiative capture and activation gamma rays have been made with both Ge(Li) and NaI(Tl) detectors, Because...
The diffusion of ions in unconsolidated sediments
F.T. Manheim
1970, Earth and Planetary Science Letters (9) 307-309
Diffusion in unconsolidated sediments generally proceeds at rates ranging from half to one twentieth of those applying to diffusion of ions and molecules in free solution. Diffusion rates are predictable with respect to porosity and path tortuosity in host sediments, and can be conveniently measured by determinations of electrical resistivity...
Static and kinetic friction of granite at high normal stress
J.D. Byerlee
1970, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts (7) 577-582
Frictional sliding on ground surfaces of granite, angle of sliding planes 30° and 45°, was investigated as a function of confining pressure. Over the normal stress range of 2–12 kb, the static frictional shear stress τs follows the relationship τs = 0·5 + 0· σn and the kinetic frictional...
The determination of low levels of cobalt-60 in environmental waters by liquid scintillation counting
H.C. Claassen
1970, Analytica Chimica Acta (52) 229-235
A method for determination of cobalt-60 in waters at levels greater than 0.5 pCi per sample is presented. A modification of the method may be used to analyze fluvial sediments and soils. After the cobalt has been separated, first as the hydroxide and then as...
Jurassic (callovian) paleotemperatures from Scotland
F.C. Tan, J.D. Hudson, M.L. Keith
1970, Earth and Planetary Science Letters (9) 421-426
Isotopic paleotemperature analyses of belemnites and ammonites from the Belemnite Sands and Oxford Clay of Staffin Bay, Isle of Skye, are presented. Ammonites are depleted in18O compared with co-existing belemnites, which give mean temperatures of around 22°C, consistent with the Skye belemnite...
Lunar radar mapping: Correlation between radar reflectivity and stratigraphy in north-western mare imbrium
G. G. Schaber, R. E. Eggleton, T.W. Thompson
1970, Nature (226) 1236-1239
DELAY-DOPPLER radar maps of the Moon obtained with the 430 MHz (70 cm wavelength) radar of the Arecibo Ionospheric Observatory in Puerto Rico (Thompson, unpublished) are at present being studied to correlate geological information with the radar reflexion characteristics of the lunar surface. Preliminary evaluation of...
Tektite 1, man-in-the-sea project: Marine Science Program
H.E. Clifton, C.V.W. Mahnken, J. C. Van Derwalker, R.A. Waller
1970, Science (168) 659-663
The Tektite experiment was designed to provide data for a number of behavioral, biomedical, and engineering studies in addition to the marine sciences program. Conditions for some of these studies were not altogether compatible with the program for the marine sciences. For example, isolation imposed by human behavioral studies precluded...
Winds over saltcedar
T. E. A. Van Hylckama
1970, Agricultural Meteorology (7) 217-233
An analysis of hourly wind speeds above and within a stand of saltcedar near Buckeye, Arizona, reveals that in 90% of all observed cases, the wind profiles above the stand can be represented by the simple logarithmic equation: uz=u*k1n">uz=u*k1n (zz0)">zz0) where...
Lithium metaborate flux in silicate analysis
C.O. Ingamells
1970, Analytica Chimica Acta (52) 323-334
Lithium metaborate is an effective flux for silicates and other rock-forming minerals. The glass resulting from fusion is mechanically strong, reasonably nonhygroscopic, and is readily soluble in dilute acids. These characteristics lead to its use in X-ray spectrography and in methods which require whole-rock solutions,...
Arsenic in detergents: Possible danger and pollution hazard
E.E. Angino, L.M. Magnuson, T.C. Waugh, O.K. Galle, J. Bredfeldt
1970, Science (168) 389-390
Arsenic at a concentration of 10 to 70 parts per million has been detected in several common presoaks and household detergents. Arsenic values of 2 to 8 parts per billion have been measured in the Kansas River. These concentrations are close to the amount (10 parts per billion) recommended by...
Missile impacts as sources of seismic energy on the moon
G.V. Latham, W.G. McDonald, H. J. Moore
1970, Science (168) 242-245
Seismic signals recorded from impacts of missiles at the White Sands Missile Range are radically different from the signal recorded from the Apollo 12 lunar module impact. This implies that lunar structure to depths of at least 10 to 20 kilometers is quite different from the typical structure of the...
Geothermal resources of the northern gulf of Mexico basin
P.H. Jones
1970, Geothermics (2) 14-26
Published geothermal gradient maps for the northern Gulf of Mexico basin indicate little or no potential for the development of geothermal resources. Results of deep drilling, from 4000 to 7000 meters or more, during the past decade however, define very sharp increases in geothermal gradient which are associated with the...
Latitudinal gradients in tertiary molluscan faunas of the Pacific coast
W.O. Addicott
1970, Palaeogeography, Palaeoclimatology, Palaeoecology (8) 287-312
Tertiary molluscan faunas of the middle latitudes of the marginal eastern North Pacific are characterized by warm-water taxa whose descendants now live in more southerly latitudes. A series of profiles in which cumulative percentages of warm-water faunal elements are plotted against latitude show progressive northward decreases in the percentage of...
Thermoluminescence of lunar samples
G. B. Dalrymple, Richard R. Doell
1970, Science (167) 713-715
Appreciable natural thermoluminescence with glow curve peaks at about 350 degrees centigrade for lunar fines and breccias and above 400 degrees centigrade for crystalline rocks has been recognized in lunar samples. Plagioclase has been identified as the principal carrier of thermoluminescence, and the difference in peak temperatures indicates compositional or...
Deuterium: Natural variations used as a biological tracer
J.D. Gleason, I. Friedman
1970, Science (169) 1085-1086
The suggestion is made that isotope tracing be carried out by monitoring the natural variations in deuterium concentrations. As an example, the natural variations in deuterium concentrations between food and water collected in Illinois and food and water collected in Colorado were used to determine the residence time of water...
Deuterium content of snow cores from Sierra Nevada area
I. Friedman, G.I. Smith
1970, Science (169) 467-470
The relative deuterium content was measured on 37 snow cores collected in April 1969 in the Sierra Nevada. The deuterium content varies inversely with altitude of collection (approximately 40 per mil per 1000 meters) but is unrelated to latitude. The altitude relationship is particularly well defined west of the crest...
Cummingtonite: A reversible, nonquenchable transition from P21/m to C2/m symmetry
C.T. Prewitt, J. J. Papike, M. Ross
1970, Earth and Planetary Science Letters (8) 448-450
Cummingtonite from the Gouverneur, New York, talc district (Sample No. U.S.N.M. 115046) with the composition, (Ca0.36Na0.06Mn0.96Mg0.57) Mg5Si8O22 (OH)2, unit cell parametersa = 9.550 ± 0.001, b = 18.007 ± 0.003, c = 5.298 ± 0.001Å, β = 102°39′ ± 1′, and space...
Paleomagnetic secular variation study of lavas from the Massif central, France
Richard R. Doell
1970, Earth and Planetary Science Letters (8) 352-362
The angular standard deviation of virtual geomagnetic poles determined from a paleomagnetic study of 31 Brunhes-age lava flows from France has been obtained. The value, referred to the axial dipole (geographic axis), is 15.2° with 95% confidence limits of 18.4° and 12.9°....
A new technique for pumping hydrogen gas
I. Friedman, K. Hardcastle
1970, Geochimica et Cosmochimica Acta (34) 125-126
A system for pumping hydrogen gas without isotopic fractionation has been developed. The pump contains uranium metal, which when heated to about 80°C reacts with hydrogen to form UH3. The UH3 is heated to above 500°C to decompose the hydride and regenerate the hydrogen....
Strontium isotopes in some Cenozoic lavas from Oregon and Washington
C. E. Hedge, R.A. Hildreth, W.T. Henderson
1970, Earth and Planetary Science Letters (8) 434-438
The87Sr/86Sr ratios have been determined in 22 volcanic rocks from Oregon and Washington. The emphasis of the study was on andesites and dacites, but several basalts were included. Most of the samples have a very limited range in strontium isotopic composition...
Effects of oil development in Arctic America
J. C. Reed
1970, Biological Conservation (2) 273-277
Large and important discoveries of petroleum were made in northern Alaska in 1968. The reserves were estimated then to be perhaps as much as ten thousand million barrels. Subsequent exploration has shown the resources to be much greater than was estimated earlier. Many...
Sulfur isotope distribution in solfatares, Yellowstone National Park
R. Schoen, R. O. Rye
1970, Science (170) 1082-1084
Sulfur isotope data on hydrogen sulfide, native sulfur, and sulfates from acid hot-spring areas at Yellowstone National Park suggest that hydrogen sulfide oxidizes to sulfur analogically, whereas sulfur undergoes biological oxidation to sulfuric acid. An exception occurs at Mammoth Hot Springs where hydrogen sulfide apparently undergoes biochemical oxidation to sulfur....
Photogeologic and thermal infrared reconnaissance surveys of the Los Negritos-Ixtlan de los Hervores geothermal area, Michoacan, Mexico
Valle R. Gomez, J. D. Friedman, S.J. Gawarecki, C.J. Banwell
1970, Geothermics (2)
New techniques, involving interpretation of panchromatic, ektachrome and ektachrome infrared aerographic photogaphs and thermographic infrared imagery recording emission from the earth's surface in middle and far infrared wavelengths (3–5μm and 8–14μm), are being introduced in geothermal investigations in Mexico to identify outstanding structural and geologic features in a rapid and...