Lungfish burrows in the Upper Triassic Chinle and Dolores Formations, Colorado Plateau
R. F. Dubiel, R.H. Blodgett, T. M. Bown
1987, Journal of Sedimentary Petrology (57) 512-521
Vertical-to-inclined, cylindrical trace fossils that occur in the Upper Triassic Chinle and Dolores Formations on the Colorado Plateau are interpreted to be the casts of lungfish burrows. The casts, which are as much as 11 cm in diameter and as much as 1.6...
Source of lead and mineralizing brines for rossie-type Pb-Zn veins in the Frontenac axis area, New York ( USA).
Robert Ayuso, Nora K. Foley, C. Erwin Brown
1987, Economic Geology (82) 489-491
Veins composed mainly of calcite and some galena, sphalerite, fluorite, and other minerals are widespread in the Frontenac axis area of New York and Ontario. In New York, the veins (Fig. 1) occur mainly west and northwest of Gouverneur (Brown, 1983). The veins, mined in the 1800s for lead,...
Recent geologic history of lake Atitlán, a caldera lake in western Guatemala
C. G. Newhall, C. K. Paull, J.P. Bradbury, A. Higuera-Gundy, L. J. Poppe, S. Self, Sharpless N. Bonar, J. Ziagos
1987, Journal of Volcanology and Geothermal Research (33) 81-107
Lake Atitlán, a caldera lake in western Guatemala, was investigated for evidence of recent volcanic and tectonic activity. No vents, faults, or folds are apparent on high-resolution seismic reflection profiles of lake sediment, representing at least 17,500 years and probably more than 35,000 years of deposition. Three post-caldera stratovolcanoes...
Archean inheritance in zircon from late Paleozoic granites from the Avalon zone of southeastern New England: An African connection
R. E. Zartman, Hermes O. Don
1987, Earth and Planetary Science Letters (82) 305-315
In southeastern New England the Narragansett Pier Granite locally intrudes Carboniferous metasedimentary rocks of the Narragansett basin, and yields a monazite UPb Permian emplacement age of 273 ± 2Ma. Zircon from the Narragansett Pier Granite contains a...
Usefulness of weak bands in midinfrared remote sensing of particulate planetary surfaces
J.W. Salisbury, B. Hapke, J.W. Eastes
1987, Journal of Geophysical Research Solid Earth (92) 702-710
Midinfrared (2.5–25 μm) reflectance spectra of minerals are often used to predict emittance qualitatively. These spectra display weak overtone and combination tone bands, which may be as diagnostic of composition as the strong fundamental molecular vibration bands usually considered for remote sensing applications, but which have been widely ignored. However,...
Uniformity and diversity in the composition of mineralizing fluids from hydrothermal vents on the southern Juan de Fuca Ridge
J.A. Philpotts, P. J. Aruscavage, Karen L. Von Damm
1987, Journal of Geophysical Research Solid Earth (92) 11327-11333
Abundances of Li, Na, K, Rb, Ca, Sr, Ba, Mn, Fe, Zn, and Si have been determined in fluid samples from seven vents located in three areas on the southern Juan de Fuca Ridge. The hydrothermal component estimated from the Mg contents of the samples ranges from 7% to 76%....
Stable isotope compositions of fossil mollusks from southern California: Evidence for a cool last interglacial ocean.
D.R. Muhs, T.K. Kyser
1987, Geology (15) 119-122
Stable isotope compositions have been determined for modern mullusks and fossil mollusks collected from uplifted marine terraces at three localities in southern California. By using a paleoclimatic model that decouples the temperature and ice-volume signals in ocean water, ocean-water temperatures off southern California...
Langrangian model of nitrogen kinetics in the Chattahoochee River
H.E. Jobson
1987, Journal of Environmental Engineering (113) 223-242
A Lagrangian reference frame is used to solve the convection‐dispersion equation and interpret water‐quality data obtained from the Chattahoochee River. The model was calibrated using unsteady concentrations of organic nitrogen, ammonia, and nitrite plus nitrate obtained during June 1977 and verified using data obtained during August 1976. Reaction kinetics of...
Examples of transient sounding from groundwater exploration in sedimentary aquifers
D.V. Fitterman
1987, Groundwater (25) 685-692
Examples of the use of transient electromagnetic soundings for three ground-water exploration problems in sedimentary aquifers are given. The examples include: (1) estimating depths to water table and bedrock in an alluvium-filled basin, (2) mapping a confined fresh-water aquifer in bedrock sediments, and (3) locating...
Ground-water flow and shallow-aquifer properties in the Rio Grande inner valley south of Albuquerque, Bernalillo County, New Mexico
K. D. Peter
1987, Water-Resources Investigations Report 87-4015
The purpose of this investigation was to describe the water table configuration and its temporal variations, estimate aquifer properties, and evaluate the interaction of groundwater and surface water in the inner valley of the Rio Grande in southern Albuquerque, New Mexico, where groundwater contamination is a continuing concern. The upper...
Earthquakes; November-December 1987
W. J. Person
1987, Earthquakes & Volcanoes (USGS) (19) 218-221
There were two major earthquakes during the last two months of the year, both in the Gulf of Alaska. Earthquake-related deaths were reported from Mexico, Japan and Indonesia. Southern California was hit by two strong earthquakes; both caused damage and some injuries. ...
Earthquakes, November-December 1986
W. J. Person
1987, Earthquakes & Volcanoes (USGS) (19) 77-79
There was one major earthquake (7.0-7.9) during this reporting period in Taiwan, a magnitude 7.8, which caused deaths and consideralbe damage. Earthquake-related deaths were reported in Bulgaria and in a mine in Poland. There was no significant earthquakes in the United States. ...
Failure of a massive earthquake-induced landslide dam in Papua New Guinea
J. P. King, I. C. Loveday, R. L. Schuster
1987, Earthquakes & Volcanoes (USGS) (19) 40-47
In many areas of the world, landslides dams are both interesting natural phenomena and significant hazards. A few of the these natural blockages attain heights that rival or exceed those of the largest manmade dams. A landslide dam in its natural state differs from a constructed embankment dam in that...
Earthquakes, January-February 1987
W. J. Person
1987, Earthquakes & Volcanoes (USGS) (19) 102-105
There were two major earthquakes (7.0-7.9) during the first two months of the year. The first, on January 30 in the South Sandwich Islands region, was in an unpopulated area; the second was on February 8 in New Guinea. In the United States the largest earthquake during this reporting period was...
Valles Marineris, Mars: Wet debris flows and ground ice
Baerbel K. Lucchitta
1987, Icarus (72) 411-429
Detailed study of the Valles Marineris equatorial troughs suggests that the landslides in that area contained water and probably were gigantic wet debris flows: one landslide complex generated a channel that has several bends and extends for 250 km. Further support for water or ice in debris masses includes rounded...
Stochastic simulation of spatially correlated geo-processes
G. Christakos
1987, Mathematical Geology (19) 807-831
In this study, developments in the theory of stochastic simulation are discussed. The unifying element is the notion of Radon projection in Euclidean spaces. This notion provides a natural way of reconstructing the real process from a corresponding process observable on a reduced dimensionality space, where analysis is theoretically easier...
The Upper Paleozoic pebbly mudstone facies of peninsular Thailand and western Malaysia - Continental margin deposits of Palaeoeurasia - Discussion
P.H. Stauffer, L.C. Peng
1987, Geologische Rundschau (76) 945-948
[No abstract available]...
Characteristics of hydrolysis of the complex Na2SnF6 in hydrothermal solutions-An experimental study
Y. Wang, C. I-Ming
1987, Chinese Journal of Geochemistry (6) 372-382
Characteristics of hydrolysis of the complex Na2SnF6, which is used as the starting material, in hydrothermal solutions have been studied at 200-602??C and 1 kbar. Experimental results show that intense hydrolysis of Na2SnF6 occurs at high temperatures and that with the rise of temperature the hydrolysis will become more intense....
Ascaulocardium armatum (Morton 1833), new genus (Late Cretaceous): the ultimate variation on the bivalve paradigm
J. Pojeta Jr., N. F. Sohl
1987, Journal of Paleontology (61)
Cretaceous clavagellid pelecypods are a poorly known group, and have previously received little study. Ascaulocardium armatum is conchologically the most complex burrowing pelecypod known. From the study of living clavagellids, it is possible to interpret the various tubes extending outward from the adventitious crypt of A. armatum as devices...
Ground-water withdrawals and changes in ground-water levels, ground-water quality, and land-surface subsidence in the Houston district, Texas, 1980-84
James F. Williams III, C.E. Ranzau Jr.
1987, Water-Resources Investigations Report 87-4153
During 1980-84, ground-water withdrawals from the Chicot and Evangeline aquifers in the Houston district decreased from 511 million gallons per day to 444 million gallons per day. This 13-percent decrease was due to the increased availability of surface water and a decreased demand for water. The largest decreases in ground-water...
New perspectives on the eruption of 1912 in the valley of ten thousand smokes, Katmai National Park, Alaska
W. Hildreth
1987, Bulletin of Volcanology (49) 680-693
New data extend our understanding of the 1912 eruption, its backfilled vent complex at Novarupta, and magma-storage systems beneath adjacent stratovolcanoes. Initial Plinian rhyolite fallout is confined to a narrow downwind sector, and its maximum thickness may occur as far as 13 km from source. In contrast, the partly contemporaneous...
A model of geomagnetic secular variation for 1980-1983
N.W. Peddie, A.K. Zunde
1987, Physics of the Earth and Planetary Interiors (48) 324-329
We developed an updated model of the secular variation of the main geomagnetic field during 1980 through 1983 based on annual mean values for that interval from 148 worldwide magnetic observatories. The model consists of a series of 80 spherical harmonics, up to and including those of degree and order...
Solid-state 13C NMR studies of dissolved organic matter in pore waters from different depositional environments
William H. Orem, Patrick G. Hatcher
1987, Organic Geochemistry (11) 73-82
Dissolved organic matter (DOM) in pore waters from sediments of a number of different depositional environments was isolated by ultrafiltration using membranes with a nominal molecular weight cutoff of 500. This > 500 molecular weight DOM represents 70–98% of the total DOM in these pore waters. We determined the gross...
Meeting future information needs for Great Lakes fisheries management
W.J. Christie, John J. Collins, Gary W. Eck, Chris I. Goddard, John M. Hoenig, Mark Holey, Lawrence D. Jacobson, Wayne MacCallum, Stephen J. Nepszy, Robert O’Gorman, James Selgeby
1987, Canadian Journal of Fisheries and Aquatic Sciences (44) 439-447
Description of information needs for management of Great Lakes fisheries is complicated by recent changes in biology and management of the Great Lakes, development of new analytical methodologies, and a transition in management from a traditional unispecies approach to a multispecies/community approach. A number of general problems with the collection...
Kinetic theory of oxygen isotopic exchange between minerals and water
R.E. Criss, R. T. Gregory, H.P. Taylor Jr.
1987, Geochimica et Cosmochimica Acta (51) 1099-1108
Kinetic and mass conservation equations are used to describe oxygen isotopic exchange between minerals and water in "closed" and open hydrothermal systems. In cases where n coexisting mineral phases having different reaction rates are present, the exchange process is described by a system of n + 1 simultaneous differential equations...
