Inferred depth of creep on the Hayward Fault, central California
J.C. Savage, M. Lisowski
1993, Journal of Geophysical Research (98) 787-793
A relation between creep rate at the surface trace of a fault, the depth to the bottom of the creeping zone, and the rate of stress accumulation on the fault is derived from Weertman's 1964 friction model of slip on a fault. A 5 ± 1...
Bacterial degradation of acetone in an outdoor model stream
R. E. Rathbun, D. W. Stephens, D. Y. Tai
1993, Environmental Pollution (79) 153-162
Diurnal variations of the acetone concentration in an outdoor model stream were measured with and without a nitrate supplement to determine if the nitrate supplement would stimulate bacterial degradation of the acetone. Acetone loss coefficients were computed from the diurnal data using a fitting procedure based on a Lagrangian particle...
Analysis of the seismic origin of landslides: Examples from the New Madrid seismic zone
R.W. Jibson, D. K. Keefer
1993, Geological Society of America Bulletin (105) 521-536
By analyzing two landslides in the New Madrid seismic zone, we develop an approach for judging if a landslide or group of landslides of unknown origin was more likely to have formed as a result of earthquake shaking or in aseismic conditions. The two landslides analyzed are representative of two...
Geothermometry and water-rock interaction in selected thermal systems in the Cascade Range and Modoc Plateau, western United States
Robert H. Mariner, T. S. Presser, William C. Evans
1993, Geothermics (22) 1-15
The sulfate—water isotope geothermometer indicates higher equilibrium temperatures than the silica or cation ratio geothermometers for the Na—Cl and Na—Ca—Cl thermal waters of the Cascade Range, Oregon and the Na—SO4 thermal waters of the Modoc Plateau, northeastern California. Sulfate concentrations in the Na—Ca—Cl waters decrease as σ18O values of the dissolved...
Basic concepts in three-part quantitative assessments of undiscovered mineral resources
D.A. Singer
1993, Nonrenewable Resources (2) 69-81
Since 1975, mineral resource assessments have been made for over 27 areas covering 5??106 km2 at various scales using what is now called the three-part form of quantitative assessment. In these assessments, (1) areas are delineated according to the types of deposits permitted by the geology,(2) the amount of metal...
Estimation of undiscovered deposits in quantitative mineral resource assessments-examples from Venezuela and Puerto Rico
D. P. Cox
1993, Nonrenewable Resources (2) 82-91
Quantitative mineral resource assessments used by the United States Geological Survey are based on deposit models. These assessments consist of three parts: (1) selecting appropriate deposit models and delineating on maps areas permissive for each type of deposit; (2) constructing a grade-tonnage model for each deposit model; and (3) estimating...
Application of mixed-mode, solid-phase extraction in environmental and clinical chemistry. Combining hydrogen-bonding, cation-exchange and Van der Waals interactions
M. S. Mills, E.M. Thurman, M.J. Pedersen
1993, Journal of Chromatography A (629) 11-21
Silica- and styrene-divinylbenzene-based mixed-mode resins that contain C8, C18 and sulphonated cation-exchange groups were compared for their efficiency in isolation of neutral triazine compounds from water and of the basic drug, benzoylecgonine, from urine. The triazine compounds were isolated by a combination of Van der Waals and hydrogen-bonding interactions, and...
Seismic response of eccentrically braced tall buildings
Mehmet Çelebi
1993, Journal of Structural Engineering (119) 1188-1205
Spectral analysis and system identification techniques are used to analyze a set of acceleration reponse records obtained during the Loma Prieta earthquake from the 47-story, moment-resisting framed and eccentrically braced Embarcadero Building (EMB). The EMB was constructed in 1979 based on the 1976 Uniform Building Code requirements and a design...
Model for humus in soils and sediments
R.L. Wershaw
1993, Environmental Science & Technology (27) 814-816
No abstract available....
Thermodynamic evaluation and restoration of volcanic gas analyses: An example based on modern collection and analytical methods
Terrance M. Gerlach
1993, Geochemical Journal (27) 305-322
Thermodynamic evaluation and restoration procedures are applied to a set of 10 volcanic gas analyses obtained by modern collection and analytical methods. The samples were collected from a vigorously fuming fissure during episode 1 of the Puu Oo eruption of Kilauea Volcano in 1983. A variety of analytical techniques were...
Fingerprinting the K/T impact site and determining the time of impact by UPb dating of single shocked zircons from distal ejecta
T.E. Krogh, S.L. Kamo, B.F. Bohor
1993, Earth and Planetary Science Letters (119) 425-429
UPb isotopic dating of single 1–3 μg zircons from K/T distal ejecta from a site in the Raton Basin, Colorado provides a powerful new tool with which to determine both the time of the impact event and...
Heat capacity and phase equilibria of almandine, Fe3Al2Si3O12
Lawrence M. Anovitz, E.J. Essene, G.W. Metz, S.R. Bohlen, E.F. Westrum Jr., B. S. Hemingway
1993, Geochimica et Cosmochimica Acta (57) 4191-4204
The heat capacity of a synthetic almandine, Fe3Al2Si3O12, was measured from 6 to 350 K using equilibrium, intermittent-heating quasi-adiabatic calorimetry and from 420 to 1000 K using differential scanning calorimetry. These measurements yield Cp298 = 342.80 ± 1.4 J/mol · K and S298o = 342.60 J/mol · K. Mössbauer characterizations show the almandine to...
Pilot studies of seismic hazard and risk in North Sulawesi Province, Indonesia
P.C. Thenhaus, S.L. Hanson, I. Effendi, E.K. Kertapati, S. T. Algermissen
1993, Earthquake Spectra (9) 97-120
Earthquake ground motions in North Sulawesi on soft soil that have a 90% probability of not been exceeded in 560 years are estimated to be 0.63 g (63% of the acceleration of gravity) at Palu, 0.31 g at Gorontalo, and 0.27 g at Manado. Estimated ground motions for rock conditions...
Is there a metric for mineral deposit occurrence probabilities?
L.J. Drew, W. D. Menzie
1993, Nonrenewable Resources (2) 92-105
Traditionally, mineral resource assessments have been used to estimate the physical inventory of critical and strategic mineral commodities that occur in pieces of land and to assess the consequences of supply disruptions of these commodities. More recently, these assessments have been used to estimate the undiscovered mineral wealth in such...
Beach profile modification and sediment transport by ice: an overlooked process on Lake Michigan
P. W. Barnes, E. W. Kempema, E. Reimnitz, M. McCormick, W. S. Weber, E.C. Hayden
1993, Journal of Coastal Research (9) 65-86
Coastal lake ice includes a belt of mobile crash and slush ice and a stable nearshore-ice complex (NIC). Sediment concentrations indicate that the NIC and the belt of brash and slush contains 180 to 280 t (113 to 175m3) of sand per kilometer of coast. This static sediment load is...
Sampling and major element chemistry of the recent (A.D. 1631-1944) Vesuvius activity
H. E. Belkin, C.R.J. Kilburn, B. de Vivo
1993, Journal of Volcanology and Geothermal Research (58) 273-290
Detailed sampling of the Vesuvius lavas erupted in the period A.D. 1631-1944 provides a suite of samples for comprehensive chemical analyses and related studies. Major elements (Si, Ti, Al, Fetotal, Mn, Mg, Ca, Na, K and P), volatile species (Cl, F, S, H2O+, H2O- and CO2), and ferrous iron (Fe2+)...
Descriptive models of major uranium deposits in China - Some results of the Workshop on Uranium Resource Assessment sponsored by the International Atomic Energy Agency, Vienna, Austria, in cooperation with China National Nuclear Corporation, Beijing, and the U.S. Geological Survey, Denver, Colorado, and Reston, Virginia
W.I. Finch, S. Feng, C. Zuyi, R.B. McCammon
1993, Nonrenewable Resources (2) 39-48
Four major types of uranium deposits occur in China: granite, volcanic, sandstone, and carbonaceous-siliceous-pelitic rock. These types are major sources of uranium in many parts of the world and account for about 95 percent of Chinese production. Descriptive models for each of these types record the diagnostic regional and local...
Model for episodic flow of high-pressure water in fault zones before earthquakes
J. Byerlee
1993, Geology (21) 303-306
In this model for the evolution of large crustal faults, water that originally came from the country rock saturates the initially highly porous and permeable fault zone. During shearing, the fault zone compacts and water flows back into the country rock, but the...
Calibrated models as management tools for stream-aquifer systems: The case of central Kansas, USA
M. Sophocleous, S.P. Perkins
1993, Journal of Hydrology (152) 31-56
We address the problem of declining streamflows in interconnected stream-aquifer systems and explore possible management options to address the problem for two areas of central Kansas: the Arkansas River valley from Kinsley to Great Bend and the lower Rattlesnake Creek-Quivira National Wildlife Refuge area. The approach we followed implements, calibrates,...
An engineering rock classification to evaluate seismic rock-fall susceptibility and its application to the Wasatch Front
E. L. Harp, M.A. Noble
1993, Bulletin of the Association of Engineering Geologists (30) 293-319
Investigations of earthquakes world wide show that rock falls are the most abundant type of landslide that is triggered by earthquakes. An engineering classification originally used in tunnel design, known as the rock mass quality designation (Q), was modified for use in rating the susceptibility of rock slopes to seismically-induced...
Relict colluvial boulder deposits as paleoclimatic indicators in the Yucca Mountain region, southern Nevada
J.W. Whitney, C.D. Harrington
1993, Geological Society of America Bulletin (105) 1008-1018
Early to middle Pleistocene boulder deposits are common features on southern Nevada hillslopes. These darkly varnished, ancient colluvial deposits stand but in stark contrast to the underlying light-colored bedrock of volcanic tuffs, and they serve as minor divides between drainage channels on modern hillslopes. To demonstrate the antiquity of these...
Anaerobes into heavy metal: Dissimilatory metal reduction in anoxic environments
Derek R. Lovley
1993, Trends in Ecology and Evolution (8) 213-217
Within the last decade, a novel form of microbial metabolism of major environmental significance has been elucidated. In this process, known as dissimilatory metal reduction, specialized microorganisms, living in anoxic aquatic sediments and ground water, oxidize organic compounds to carbon dioxide with metals serving as the oxidant. Recent studies have...
Upper-crustal structure beneath the Columbia River Basalt Group, Washington: Gravity interpretation controlled by borehole and seismic studies
R. W. Saltus
1993, Geological Society of America Bulletin (105) 1247-1259
A three-dimensional gravity model based on deep-borehole stratigraphy, densities from borehole gravimetry, and crustal structure from deep seismic and electrical surveys puts limits on sub-basalt crustal structure in the northwest quadrant of the Columbia Plateau, Washington. The gravity model indicates that the Miocene...
Atrazine degradation in a small stream in Iowa
D.W. Kolpin, S. J. Kalkhoff
1993, Environmental Science & Technology (27) 134-139
A study was conducted during 1990 through an 11.2-km reach of Roberts Creek in northeastern Iowa to determine the fate of atrazine in a surface water environment Water samples were collected at ~1-month intervals from April through November during stable low to medium flow conditions and analyzed for atrazine and...
Tectonic characterization of a potential high-level nuclear waste repository at Yucca Mountain, Nevada
John W. Whitney, Dennis W. O’Leary
1993, Conference Paper, Dynamic Analysis and Design Considerations for High-Level Nuclear Waste Repositories
Tectonic characterization of a potential high-level nuclear waste repository at Yucca Mountain, Nevada, is needed to assess seismic and possible volcanic hazards that could affect the site during the preclosure (next 100 years) and the behavior of the hydrologic system during the postclosure (the following 10,000 years) periods. Tectonic characterization...
