Dissolution and analysis of amorphous silica in marine sediments
D.W. Eggimann, F.T. Manheim, P.R. Betzer
1980, Journal of Sedimentary Petrology (50) 215-225
The analytical estimation of amorphous silica in selected Atlantic and Antarctic Ocean sediments, the U.S.G.S. standard marine mud (MAG-1), A.A.P.G. clays, and samples from cultures of a marine diatom, Hemidiscus, has been examined. Quantitative recovery of sedimentary amorphous silica was achieved by reacting...
Treasures from the deep ( Metallic nodules).
D.Z. Piper
1980, Water Spectrum (13) 8-15
The composition, distribution, metric growth rates and variations in sea-floor metallic nodules are outlined and discussed The considerable age, slow accretion and relationship to underlying sediments are problems of origin which are yet to be solved and some speculative answers are discussed. Mining of the nodules is reviewed and its...
Stress measurements at depth in the vicinity of the San Andreas fault. Implications for the magnitude of shear stress at depth
M.D. Zobach, H. Tsukahara, S. Hickman
1980, Journal of Geophysical Research Solid Earth (85) 6157-6173
Using the hydraulic fracturing technique, we have made a systematic series of in situ stress measurements in wells drilled near the San Andreas fault. In an attempt to provide constraints for the magnitude of shear stress on the San Andreas fault at depth we have measured both the variation of...
Elastic moduli of rock glasses under pressure to 8 kilobars and geophysical implications
R. Meister, E.C. Robertson, R.W. Werke, R. Raspet
1980, Journal of Geophysical Research Solid Earth (85) 6461-6470
Shear and longitudinal velocities were measured by the ultrasonic phase comparison method as a function of pressure to 8 kbar on synthetic glasses of basalt, andesite, rhyolite, and quartz composition and on natural obsidian. Velocities of most of the glasses decrease anomalously with pressure, but increasingly more-normal behavior occurs with...
Gas and hydrogen isotopic analyses of volcanic eruption clouds in Guatemala sampled by aircraft
W.I. Rose Jr., R.D. Cadle, L.E. Heidt, I. Friedman, A.L. Lazrus, B.J. Huebert
1980, Journal of Volcanology and Geothermal Research (7) 1-10
Gas samples were collected by aircraft entering volcanic eruption clouds of three Guatemalan volcanoes. Gas chromatographic analyses show higher H2 and S gas contents in ash eruption clouds and lower H2 and S gases in vaporous gas plumes. H isotopic data demonstrate lighter isotopic distribution of water vapor in ash...
Computational methods for inverse problems in geophysics: Inversion of travel time observations
V. Pereyra, H.B. Keller, W.H.K. Lee
1980, Physics of the Earth and Planetary Interiors (21) 120-125
General ways of solving various inverse problems are studied for given travel time observations between sources and receivers. These problems are separated into three components: (a) the representation of the unknown quantities appearing in the model; (b) the nonlinear least-squares problem; (c) the direct, two-point ray-tracing problem used to compute...
Petroleum geology of Kodiak Shelf, Alaska.
Michael A. Fisher
1980, American Association of Petroleum Geologists Bulletin (64) 1140-1157
Organic geochemical data show that Cenozoic rocks on Kodiak Island, in Albatross basin, and under the continental slope generally contain less than 0.5 wt. % organic carbon. Moreover, kerogen from all rocks analyzed is predominantly (60 to 100%) herbaceous; woody and coaly kerogens are present in secondary (20 to 40%)...
Faulting caused by groundwater level declines, San Joaquin Valley, California
Thomas L. Holzer
1980, Water Resources Research (16) 1065-1070
Approximately 230 mm of aseismic vertical offset of the land surface across the Pond-Poso Creek fault in the San Joaquin Valley, California, probably is related to groundwater withdrawal for crop irrigation. The scarp is approximately 3.4 km long and occurs in an area where the land subsided more than 1.5...
Rate of mercury loss from contaminated estuarine sediments
Michael H. Bothner, R.A. Jahnke, M. L. Peterson, R. Carpenter
1980, Geochimica et Cosmochimica Acta (44) 273-285
The concentration of mercury in contaminated estuarine sediments of Bellingham Bay, Washington was found to decrease with a half-time of about 1.3 yr after the primary anthropogenic source of mercury was removed. In situ measurements of the mercury flux from sediments, in both dissolved and volatile forms, could not account...
Hydraulic piston coring of late Neogene and Quaternary sections in the Caribbean and equatorial Pacific: Preliminary results of Deep Sea Drilling Project leg 68
W.L. Prell, James V. Gardner, Charles Adelseck, Gretchen Blechschmidt, Andrew J. Fleet, Lloyd D. Keigwin, Dennis V. Kent, Michael T. Ledbetter, Ulrich Mann, Larry Mayer, William R. Reidel, Constance Sancetta, Dann J. Spariosu, Herman B. Zimmerman
1980, Geological Society of America Bulletin (91) 433-444
Leg 68 of the Deep Sea Drilling Project used the newly developed Hydraulic Piston Corer (HPC) to recover two virtually continuous, undisturbed sections of late Neogene and Quaternary sediment. The sites are located in the western Caribbean (Site 502, 4 holes) and in...
A generalized garnet-forming reaction for metaigneous rocks in the Adirondacks
J. M. McLelland, P.R. Whitney
1980, Contributions to Mineralogy and Petrology (72) 111-122
A generalized reaction is presented to account for garnet formation in a variety of Adirondack metaigneous rocks. This reaction, which is the sum of five partial reactions written in aluminum-fixed frames of reference, is given by: 4(y+1+w)Anorthite+4 k(y+1+2 w)Olivine +4(1-k)(y+1+2 w)Fe-oxide+(8(y+1) -4 k(y+1+2 w))Orthopyroxene = 2(y+1)Garnet +2(y+1+2 w)Clinopyroxene+4 wSpinel where...
The provenance of rutile.
E. R. Force
1980, Journal of Sedimentary Petrology (50) 485-488
Most coarse detrital rutile is derived from high-grade metamorphic rocks. Contrary to a conventional assumption, independent rutile grains are particularly rare in igneous rocks except alkalic rocks. The use of rutile in the ZTR (zircon-tourmaline-rutile) index of mineralogic maturity is only partially valid,...
The morphology of the Martian surface
M. H. Carr
1980, Space Science Reviews (25) 231-284
Most of the southern hemisphere of Mars is densely cratered and stands 1-3 km above the topographic datum. The northern hemisphere is more sparsely cratered and elevations are generally below the datum. A broad rise, the Tharsis bulge, centered at 14?? S, 101?? W, is 8000 km across and 10...
Size distribution of Amazon River bed sediment
C.F. Nordin, R.H. Meade, W. F. Curtis, N.J. Bosio, P.M.B. Landim
1980, Nature (286) 52-53
The first recorded observations of bed material of the Amazon River were made in 1843 by Lt William Lewis Herndon of the US Navy, when he travelled the river from its headwaters to its mouth, sounding its depths, and noting the nature of particles caught in a heavy grease smeared...
Leg 67: the Deep Sea Drilling Project Mid-America Trench transect off Guatemala.
Roland E. von Huene
1980, Geological Society of America Bulletin (91) 421-432
Drilling on the Cocos plate recovered a basal chalk sequence deposited during early and mid-Miocene time, a short interval of abyssal red clay, and an upper sequence of late Miocene and younger sediment deposited within an area influenced by a terrigenous source. In the trench, a mud and sand fill...
Late Wisconsin and Holocene tectonic stability of the United States mid-Atlantic coastal region
B. W. Blackwelder
1980, Geology (8) 534-537
Deposits that formed in the intertidal zone during sea-level rise 12,000 to 9,000 yr ago have undergone very little differential vertical deformation in the area between New York City and South Carolina. The lack of north-south vertical deformation contrasts with tide-gauge and with...
Debris-flow deposits of Early Miocene age, Deadman Stream, Marlborough, New Zealand.
D.W. Lewis, M.G. Laird, R.D. Powell
1980, Sedimentary Geology (27) 83-118
Detailed analysis is presented of a conformable succession of conglomerates and sandstones lying between massive marine mudstones. The coarse sediments reflect deposition by a spectrum of subaqueous debris-flow mechanisms during an early pulse of tectonism that ultimately resulted in Plio-Pleistocene eversion of the Kaikoura Mountains. Sparse pebbly mudstones and rare...
Crystallization history of Kilauea Iki lava lake as seen in drill core recovered in 1967-1979
Rosalind Tuthill Helz
1980, Bulletin Volcanologique (43) 675-701
Kilauea Iki lava lake formed during the 1959 summit eruption, one of the most picritic eruptions of Kilauea Volcano in the twentieth century. Since 1959 the 110 to 122 m thick lake has cooled slowly, developing steadily thickening upper and lower crusts, with a lens of more molten lava in...
A model to forecast short-term snowmelt runoff using synoptic observations of streamflow, temperature, and precipitation
Wendell V. Tangborn
1980, Water Resources Research (16) 778-786
Snowmelt runoff is forecast with a statistical model that utilizes daily values of stream discharge, gaged precipitation, and maximum and minimum observations of air temperature. Synoptic observations of these variables are made at existing low- and medium-altitude weather stations, thus eliminating the difficulties and expense of new, high-altitude installations. Four...
Origin of gasoline-range hydrocarbons and their migration by solution in carbon dioxide in Norton basin, Alaska.
Keith A. Kvenvolden, George E. Claypool
1980, American Association of Petroleum Geologists Bulletin (64) 1078-1086
Carbon dioxide from a submarine seep in Norton Sound, Alaska, carries a minor component of gas- and gasoline-range hydrocarbons. The molecular and isotopic compositions of the hydrocarbon gases and the presence of gasoline-range hydrocarbons indicate that these molecules are derived from thermal alteration of marine and/or nonmarine organic matter buried...
Arctic sea-ice variations from time-lapse passive microwave imagery
W. J. Campbell, R.O. Ramseier, H.J. Zwally, P. Gloersen
1980, Boundary-Layer Meteorology (18) 99-106
This paper presents: (1) a short historical review of the passive microwave research on sea ice which established the observational and theoretical base permitting the interpretation of the first passive microwave images of Earth obtained by the Nimbus-5 ESMR; (2) the construction of a time-lapse motion picture film of a...
Geology and biology of Oceanographer submarine canyon.
P. C. Valentine, J. R. Uzmann, R.A. Cooper
1980, Marine Geology (38) 283-312
Santonian beds more than 100 m thick are the oldest rocks collected from the canyon. Quaternary silty clay veneers the canyon walls in many places and is commonly burrowed by benthic organisms that cause extensive erosion of the canyon walls, especially in the depth zone (100-1300 m) inhabited by the...
Kinetic model for the short-term dissolution of a rhyolitic glass
A. F. White, H.C. Claassen
1980, Chemical Geology (28) 91-109
Aqueous dissolution experiments with the vitric phase of a rhyolitic tuff were performed at 25??C and constant pH in the range 4.5-7.5. Results suggest interchange of aqueous hydrogen ions for cations situated both on the surface and within the glass. At time intervals from 24 to 900 hr., dissolution kinetics...
Studies of San Francisco Bay by the U.S. Geological Survey
R. T. Cheng, T. J. Conomos
1980, Conference Paper, Proceedings, 26th annual meeting of the institute of environmental sciences
No abstract available ...
Records of ground-water recharge and discharge, 1934-78; water levels, 1975-78; and chemical quality of water, 1977-78, for the Edwards aquifer in the San Antonio area, Texas
R.D. Reeves, R.W. Maclay, M.F. Davis
1980, Edwards Underground Water District Bulletin 38
No abstract available....
