Constraints from fluid inclusions on sulfide precipitation mechanisms and ore fluid migration in the Viburnum Trend lead district, Missouri
E. L. Rowan, D. L. Leach
1989, Economic Geology (84) 1948-1965
Measurements on fluid inclusions in hydrothermal dolomite cements place constraints on sulfide precipitation mechanisms and on the thermal-hydrologic processes which formed the Viburnum Trend Mississippi Valley-type lead district. Homogenization temperatures and freezing point depressions were determined for fluid inclusions in Bonneterre Dolomite-hosted dolomite cements in mine samples, as well as...
Thrust faults and related structures in the crater floor of Mount St. Helens volcano, Washington
W.W. Chadwick Jr., D. A. Swanson
1989, Geological Society of America Bulletin (101) 1507-1519
A lava dome was built in the crater of Mount St. Helens by intermittent intrusion and extrusion of dacite lava between 1980 and 1986. Spectacular ground deformation was associated with the dome building events and included the development of a system of radial...
Depositional environments and tectonic controls on the coal-bearing Lower to Middle Jurassic Yan'an Formation, southern Ordos Basin, China
E. A. Johnson, Liu Shu, Zhang Yonglin
1989, Geology (17) 1123-1126
The Ordos Basin of north-central China is well known for vast energy resources. This nonmarine interior basin developed on the North China-Korean platform following the Late Triassic Indochina orogeny and, for a time, contained a large freshwater lake prior to being uplifted into...
Geochemistry of intrusive rocks associated with the Latir volcanic field, New Mexico, and contrasts between evolution of plutonic and volcanic rocks
C.M. Johnson, G.K. Czamanske, P. W. Lipman
1989, Contributions to Mineralogy and Petrology (103) 90-109
Plutonic rocks associated with the Latir volcanic field comprise three groups: 1) ???25 Ma high-level resurgent plutons composed of monzogranite and silicic metaluminous and peralkaline granite, 2) 23-25 Ma syenogranite, and alkali-feldspar granite intrusions emplaced along the southern caldera margin, and 3) 19-23 Ma granodiorite and granite plutons emplaced south...
The dependence of peak horizontal acceleration on magnitude, distance, and site effects for small-magnitude earthquakes in California and eastern North America
K.W. Campbell
1989, Bulletin of the Seismological Society of America (79) 1311-1346
One-hundred and ninety free-field accelerograms recorded on deep soil (> 10 m deep) were used to study the near-source scaling characteristics of peak horizontal acceleration for 91 earthquakes (2.5 ≦ ML ≦ 5.0) located primarily in California. Of the six attenuation relationships developed in this study, the one considered most...
Geochemistry of placer gold, Koyukuk-Chandalar mining district, Alaska
E. L. Mosier, J. B. Cathrall, J.C. Antweiler, R. B. Tripp
1989, Journal of Geochemical Exploration (31) 97-115
The Koyukuk-Chandalar mining district of the Brooks Range mineral belt in north-central Alaska contains numerous placer gold deposits but few known lode gold sources. Gold grains, collected from 46 placer localities and 6 lode gold sites in the district, were analyzed for Ag and 37 trace elements utilizing direct current-arc...
Zinc movement in sewage-sludge-treated soils as influenced by soil properties, irrigation water quality, and soil moisture level
J.E. Welch, L.J. Lund
1989, Soil Science (147) 208-214
A soil column study was conducted to assess the movement of Zn in sewage-sludge-amended soils. Varables investigated were soil properties, irrigation water quality, and soil moisture level. Bulk samples of the surface layer of six soil series were packed into columns, 10.2 cm in diameter and 110 cm in length....
Urban watershed data for the United States
Janice M. Fulford
1989, Conference Paper
The contents of an urban watershed data base compiled for a national urban flood-frequency study by the U.S. Geological Survey are described. The data base includes information for 269 urbanized watersheds in 56 metropolitan areas in 31 states in the continental United States and Hawaii....
Evidence for an Early Archean component in the Middle to Late Archean gneisses of the Wind River Range, west-central Wyoming: conventional and ion microprobe U-Pb data
J. N. Aleinikoff, I.S. Williams, W. Compston, J. S. Stuckless, R. G. Worl
1989, Contributions to Mineralogy and Petrology (101) 198-206
Gneissic rocks that are basement to the Late Archean granites comprising much of the Wind River Range, west-central Wyoming, have been dated by the zircon U-Pb method using both conventional and ion microprobe techniques. A foliated hornblende granite gneiss member from the southern border of the Bridger batholith is 2670??13...
Geologic framework of the offshore region adjacent to Delaware
R.N. Benson, J.H. Roberts
1989, Marine Geology (90) 103-111
Several multichannel, common depth point (CDP) seismic reflection profiles concentrated in the area of the entrance to Delaware Bay provide a tie between the known onshore geology of the Coastal Plain of Delaware and the offshore geology of the Baltimore Canyon...
Effect of far-field slope on morphologic dating of scarplike landforms
Thomas C. Hanks, D.J. Andrews
1989, Journal of Geophysical Research Solid Earth (94) 565-573
The principal finding of this paper is that the far-field slope has a first-order effect on model age determinations of scarplike landforms in weakly consolidated terrains. Observationally, this can be demonstrated in two ways using the Lake Bonneville and Lahontan shoreline scarps as separate and combined data sets. Use of...
South Arch volcanic field—Newly identified young lava flows on the sea floor south of the Hawaiian Ridge
Peter W. Lipman, David A. Clague, James G. Moore, Robin T. Holcomb
1989, Geology (17) 611-614
Several young lava fields were imaged by GLORIA sidescan sonar along the Hawaiian Arch south of Hawaii. The largest, 35 by 50 km across, includes a central area characterized by high sonar backscatter and composed of several flow lobes radiating from a vent area. Reflection profiling and sea-floor photography indicate...
Overview of Devonian Duperow formation production, Billings anticline, North Dakota
Randolph B. Burke
1989, Oil & Gas Journal (87) 80-83
Oil exploration on the Billings anticline began in earnest in 1978, which is a north-plunging structure in the north central part of southwestern North Dakota. Forty-two fields are included in the Billings anticline area. This paper discusses the following features of the Billings anticline: structure, lithology, Duperow production, and some...
Radiocarbon dates for lava flows from northeast rift zone of Mauna Loa Volcano, Hilo 7 1/2 minute quadrangle, Island of Hawaii
J.M. Buchanan-Banks, J. P. Lockwood, M. Rubin
1989, Radiocarbon (31) 179-186
Twenty-eight 14C analyses are reported for carbonized roots and other plant material collected from beneath 15 prehistoric lava flows erupted from the northeast rift zone (NERZ) of Mauna Loa Volcano (ML) utilizing the recovery techniques of Lockwood and Lipman (1980). Most samples were collected from the Hilo 7 1/2’ quadrangle...
The non-participation of organic sulphur in acid mine drainage generation
D.J. Casagrande, R. B. Finkelman, F.T. Caruccio
1989, Environmental Geochemistry and Health (11) 187-192
Acid mine drainage is commonly associated with land disturbances that encounter and expose iron sulphides to oxidising atmospheric conditions. The attendant acidic conditions solubilise a host of trace metals. Within this flow regime the potential exists to contaminate surface drinking water supplies with a variety of trace materials. Accordingly, in...
Artificial reef observations from a manned submersible off southeast Florida
E.A. Shinn, R.I. Wicklund
1989, Bulletin of Marine Science (44) 1041-1050
Examination of 16 artificial reef structures in depths ranging from 30-120m indicated that the highest numbers of fish are found around reefs in water shallower than 46m. Fewer fish, especially those with tropical coral reef affinities, <46m was probably caused by a thermocline. Algae and reef community encrusters, abundant on...
Statistical frequency analysis of flood records
W. Kirby
1989, Conference Paper
The U.S. Geological Survey, like other Federal agencies, uses Hydrology Subcommittee Bulletin 17 for guidance in statistical frequency analysis of flood records. This paper describes the formal statistical and computational aspects of the Bulletin 17 methodology. The methodology includes provisions for dealing with high and low out-liers, historic peaks, and...
Large-scale magnetic field perturbation arising from the 18 May 1980 eruption from Mount St. Helens, Washington
R.J. Mueller, M.J.S. Johnston
1989, Physics of the Earth and Planetary Interiors (57) 23-31
A traveling magnetic field disturbance generated by the 18 may 1980 eruption of Mount St. Helens at 1532 UT was detected on an 800-km linear array of recording magnetometers installed along the San Andreas fault system in California, from San Francisco to the Salton Sea. Arrival times of the disturbance...
The north Panama earthquake of 7 September 1882: Evidence for active underthrusting
C. Mendoza, S. Nishenko
1989, Bulletin of the Seismological Society of America (79) 1264-1269
No abstract available....
Optimal-adaptive filters for modelling spectral shape, site amplification, and source scaling
Erdal Safak
1989, Soil Dynamics and Earthquake Engineering (8) 75-95
Optimal filtering techniques have been used successfully in various areas in science and engineering. They are based on statistical properties of the signal and the noise, and stochastic approximation theory. In addition to filtering, optimal filters can also be used for smoothing, prediction, and system identification. This paper introduces some...
High velocity anomaly beneath the Deccan volcanic province: Evidence from seismic tomography
H. M. Iyer, V.K. Gaur, S.S. Rai, D.S. Ramesh, C.V.R. Rao, D. Srinagesh, K. Suryaprakasam
1989, Proceedings of the Indian Academy of Sciences - Earth and Planetary Sciences (98) 31-60
Analysis of teleseismic P-wave residuals observed at 15 seismograph stations operated in the Deccan volcanic province (DVP) in west central India points to the existence of a large, deep anomalous region in the upper mantle where the velocity is a few per cent higher than in the surrounding region. The...
Remarkable isotopic and trace element trends in potassic through sodic Cretaceous plutons of the Yukon-Koyukuk Basin, Alaska, and the nature of the lithosphere beneath the Koyukuk terrane
Joseph G. Arth, Robert E. Criss, Clara C. Zmuda, Nora K. Foley, W. W. Patton Jr., T. P. Miller
1989, Journal of Geophysical Research B: Solid Earth (94) 15957-15968
During the period from 110 to 80 m.y. ago, a 450-km-long magmatic belt was active along the northern margin of Yukon-Koyukuk basin and on eastern Seward Peninsula. The plutons intruded Upper Jurassic(?) and Lower Cretaceous volcanic arc rocks and Cretaceous sedimentary rocks in Yukon-Koyukuk basin and Proterozoic and lower Paleozoic...
Transport of microspheres and indigenous bacteria through a sandy aquifer: Results of natural- and forced-gradient tracer experiments
R.W. Harvey, L.H. George, R. L. Smith, D.R. LeBlanc
1989, Environmental Science & Technology (23) 51-56
Transport of indigenous bacteria through sandy aquifer sediments was investigated in forced- and natural-gradient tracer teste. A diverse population of bacteria was collected and concentrated from groundwater at the site, stained with a DNA-specific fluorochrome, and injected back into the aquifer. Included with the injectate were a conservative tracer (Br-...
Active faulting and deformation of the Coalinga anticline as interpreted from three-dimensional velocity structure and seismicity
D. Eberhart-Phillips
1989, Journal of Geophysical Research Solid Earth (94) 15565-15586
This work gives a clear picture of the geometry of aftershock seismicity in a large thrust earthquake. Interpretation of hypocenters and fault plane solutions, from the 1983 Coalinga, Coast Range California, earthquake sequence, in combination with the three-dimensional velocity structure shows that the active faulting beneath the fold primarily consists...
Petroleum geology of the mid-Atlantic continental margin, offshore Virginia
K.C. Bayer, R. C. Milici
1989, Marine Geology (90) 87-94
The Baltimore Canyon Trough, a major sedimentary basin on the Atlantic continental shelf, contains up to 18 km of Mesozoic and Cenozoic strata. The basin has been studied extensively by multichannel common depth point (CDP) seismic reflection profiles and has been...
