Paleohydrologic evolution and geochemical dynamics of cumulative supergene metal enrichment at La Escondida, Atacama Desert, northern Chile
Charles N. Alpers, G.H. Brimhall
1989, Economic Geology (84) 229-255
Quantitative limonite mapping within the leached capping of the porphyry copper deposit at La Escondida, Chile, permits reconstruction of the paleohydrologic and chemical evolution of a well-developed supergene ore-forming system. The mineralogy, textures, and relative abundance of supergene limonite minerals (hematite, goethite, and jarosite) are used to reconstruct the former...
Analysis of exceptionally large tremors in two gold mining districts of South Africa
Art McGarr, J. Bicknell, E. Sembera, R.W.E. Green
1989, Pure and Applied Geophysics PAGEOPH (129) 295-307
An investigation of ground motion, recorded using broad-band, wide dynamic-range digital seismographs, of large mine tremors from two South African mining districts with different geologic settings, reveals some essential differences in both seismic source and ground motion parameters. In the Klerksdorp district where the strata are offset by major throughgoing...
Seismic response of a large-span roof diaphragm
Mehmet Çelebi, Giovanni Bongiovanni, Erdal Safak, A. Gerald Brady
1989, Earthquake Spectra (5) 337-350
Records obtained from the West Valley College Gymnasium in Saratoga, California during the 1984 Morgan Hill earthquake are used to study the dynamic behavior of the overall gymnasium as well as its flexible disaphragm. The ground-level motions recorded in the two orthogonal axes of the structure differ considerably in peak...
Carbon isotope effects associated with autotrophic acetogenesis
J.T. Gelwicks, J.B. Risatti, J.M. Hayes
1989, Organic Geochemistry (14) 441-446
The carbon kinetic isotope effects associated with synthesis of acetate from CO2 and H2 during autotrophic growth of Acetobacterium woodii at 30°C have been measured by isotopic analyses of CO2, methyl-carbon, and total acetate. Closed systems allowing construction of complete mass balances at varying stages of...
Heat capacities and entropies at 298.15 K of MgTiO3 (geikielite), ZnO (zincite), and ZnCO3 (smithsonite)
R. A. Robie, H.T. Haselton Jr., B. S. Hemingway
1989, Journal of Chemical Thermodynamics (21) 743-749
Heat capacities of synthetic MgTiO3 (geikielite), ZnO (zincite), and natural crystals of smithsonite (ZnCO3) were measured between 9 and 366 K using an automatic adiabatically shielded calorimeter. At 298.15 K the standard molar entropies Smo of MgTiO3, ZnO, and ZnCO3 are (74.64 ?? 0.15), (43.16 ?? 0.09), and (81.19 ??...
Mineral saturation states in natural waters and their sensitivity to thermodynamic and analytical errors
D. Kirk Nordstrom, James W. Ball
1989, Science Geological Bulletin (42) 269-280
Saturation indices computed with WATEQ4F chemical analyses from a groundwater in crystalline bedrock and a surface water receiving acid mine drainage are frequently at or above saturation with respect to calcite, fluorite, barite, gibbsite and ferrihydrite. Deep granitic groundwaters from Stripa, Sweden, are supersaturated with respect to calcite and fluorite....
The prediction of aquatic sediment-associated trace element concentration using selected geochemical factors
A. J. Horowitz, K. A. Elrick, R. P. Hooper
1989, Hydrological Processes (3) 347-364
Multiple linear regression models calculated from readily obtainable chemical and physical parameters can explain a high percentage (70 per cent or greater) of observed sediment-trace element variance for Cu, Zn, Pb, Cr, Ni, Co, As, Sb, Se, and Hg in a widely divergent suite of...
Use of multivariate analysis for determining sources of solutes found in wet atmospheric deposition in the United States
R. P. Hooper, N.E. Peters
1989, Environmental Science & Technology (23) 1263-1268
No abstract available....
Aqueous chlorination of resorcinol
V.L. Heasley, M.D. Burns, N.A. Kemalyan, T.C. Mckee, H. Schroeter, B.R. Teegarden, S.E. Whitney, R.L. Wershaw
1989, Environmental Toxicology and Chemistry (8) 1159-1163
An investigation of the aqueous chlorination (NaOCl) of resorcinol is reported. The following intermediates were detected in moderate to high yield at different pH values and varying percentages of chlorination: 2-chloro-, 4-chloro-, 2,4-dichloro-, 4,6-dichloro- and 2,4,6-trichlororesorcinol. Only trace amounts of the intermediates were detected when the chlorination was conducted in...
Replacement of native oak and hickory tree species by the introduced American chestnut (Castanea dentata) in southwestern Wisconsin
Frederick L. Paillet, P. A. Rutter
1989, Canadian Journal of Botany (67) 3457-3469
American chestnut was introduced at West Salem, Wisconsin, about 1880 and had begun to replace native tree species in adjacent oak-hickory woodland before 1930. Chestnut is now an important canopy species over about 20 ha of forested ridge extending north and south of the original plantation. A smaller area of less...
Isotopic and trace element variations in the Ruby Batholith, Alaska, and the nature of the deep crust beneath the Ruby and Angayucham Terranes
Joseph G. Arth, Clara C. Zmuda, Nora K. Foley, Robert E. Criss, W. W. Patton Jr., T. P. Miller
1989, Journal of Geophysical Research B: Solid Earth (94) 15941-15955
Thirty-six samples from plutons of the Ruby batholith of central Alaska were collected and analyzed for 22 trace elements, and many were analyzed for the isotopic compositions of Sr, Nd, O, and Pb in order to delimit the processes that produced the diversity of granodioritic to granitic compositions, to deduce...
Non-energy minerals and surficial geology of the continental margin of Maryland
R.T. Kerhin
1989, Marine Geology (90) 95-102
The surficial sediments have been mapped and the shallow geologic framework outlined of the Maryland inner continental shelf. The initial study encompassed a small area offshore of Assateague Island but was extended northward to include the Ocean City area and eastward...
Inner shelf deposits of the Louisiana-Mississippi-Alabama region, Gulf of Mexico
Jack L. Kindinger, Shea Penland, S. Jeffress Williams, John R. Suter
1989, Gulf Coast Association of Geological Societies Transactions (39) 413-420
The late Quaternary morphology, shallow stratigraphy and sediment distribution of the Louisiana-Mississippi-Alabama inner shelf region are the product of transgressive and regressive sedimentary processes. Shelf sedimentary facies were deposited by deltaic progradation, followed by shoreface erosion and submergence. This information is based on interpretations and synthesis of more than 4,160...
Notes about the Armenia earthquake, 7 December 1988
R. A. Kerr
1989, Earthquakes & Volcanoes (USGS) (21) 68-78
The Earth's crust is a jigsaw of rigid plates like huge paving stones. According to the theory of plate tectonics, these lithosphere plates are constantly in motion, slowly realigning themselves with the passage of time. Ninety to niety-five percent of all earthquakes occur where the plates collide with each other. In...
Holocene sand shoals offshore of the Mississippi River delta plain
Shea Penland, John R. Suter, Randolph A. McBride, S. Jeffress Williams, Jack L. Kindinger, Ron Boyd
1989, Gulf Coast Association of Geological Societies Transactions (39) 471-480
Offshore of the Mississippi River delta plain lies a series of Holocene sand shoals marking the position of ancient submerged shorelines associated with younger shelf-phase delta plains. These submerged shorelines represent positions when sea level stood lower than present. Short periods of rapid sea level rise during the Holocene transgression,...
Impacts of exploratory drilling for oil and gas on the benthic environment of Georges Bank
J. M. Neff, Michael H. Bothner, N. J. Maciolek, J. F. Grassle
1989, Marine Environmental Research (27) 77-114
A 3-year monitoring program was performed to assess the impacts of exploratory drilling for oil and gas on the benthic environment of Georges Bank, an important commercial fishery region in the North Atlantic east of Massachusetts, USA. Surficial sediments were sampled for chemical and benthic infaunal analysis and bottom still...
Recent carbonate slope sediments and sedimentary processes bordering a non-rimmed platform: southwest Florida continental margin
Gregg R. Brooks, Charles W. Holmes
1989, Book chapter, Controls on carbonate platforms and basin development
No abstract available....
Marine origin of pyritic sulfur in the Lower Bakerstown coal bed, Castleman coal field, Maryland (U.S.A.)
P.C. Lyons, J. F. Whelan, F.T. Dulong
1989, International Journal of Coal Geology (12) 329-348
The amount, kind, distribution, and genesis of pyrite in the Lower Bakerstown coal bed in a 150 × 15 m area of the Bettinger mine, Castleman coal field, Maryland, were studied by various analytical techniques. The mined coal, which had a...
Preliminary map of upper Eocene to Holocene volcanic and related rocks of the Cascade Range, Oregon
David R. Sherrod, James G. Smith
1989, Open-File Report 89-14
Since 1979 the Geothermal Research Program of the U.S. Geological Survey has carried out multidisciplinary research in the Cascade Range. The goal of this research is to understand the geology, tectonics, and hydrology of the Cascades in order to characterize and quantify geothermal resource potential. A major goal of the...
Wetland and peat resource map of the South Merrimack 7.5-minute quadrangle, New Hampshire
Cornelia Clermont Cameron, D. A. Emery
1989, Open-File Report 88-695
U.S. Geological Survey...
Spatial patterns of aftershocks of shallow focus earthquakes in California and implications for deep focus earthquakes
A.J. Michael
1989, Journal of Geophysical Research Solid Earth (94) 5615-5626
Previous workers have pioneered statistical techniques to study the spatial distribution of aftershocks with respect to the focal mechanism of the main shock. Application of these techniques to deep focus earthquakes failed to show clustering of aftershocks near the nodal planes of the main shocks. To better understand the behavior...
Taking the pulse of the San Andreas Fault
R. A. Kerr
1989, Earthquakes & Volcanoes (USGS) (21) 112-115
The ninth of January, 1989, was the 32nd anniversary of the great southern California earthquake of 1857. the latest research shows that, on average, at least part of the section of the San Andreas fault that broke then should break again this year. But the same research suggests that the fault's...
New fault picture points toward San Francisco Bay area earthquakes
R. A. Kerr
1989, Earthquakes & Volcanoes (USGS) (21) 116-120
Recent earthquakes and a new way of looking at faults suggest that damaging earthquakes are closing in on the San Francisco area. Earthquakes Awareness Week 1989 in northern California started off with a bang on Monday, 3 April, when a magnitude 4.8 earthquake struck 15 kilometers northeast of San Jose....
Adaptive modeling, identification, and control of dynamic structural systems. I. Theory
Erdal Safak
1989, Journal of Engineering Mechanics (115) 2386-2405
A concise review of the fheory of adaptive modeling, identification, and control of dynamic structural systems based on discrete‐time recordings is presented. Adaptive methods have four major advantages over the classical methods: (1) Removal of the noise from the signal is done over the whole frequency band; (2) time‐varying characteristics...
Observed parameters for turbidity-current flow in channels, Reserve Fan, Lake Superior
W. R. Normark
1989, Journal of Sedimentary Petrology (59) 423-431
Fine-grained tailings discharged from a taconite-ore processing operation near the shore of Lake Superior produced turbidity currents that transported the sediment from a small delta into deep water at Silver Bay, Minnesota. Deposition over nearly 20 years produced a sublacustrine fan with two...
