Geochemistry and intrusive history of the Ashland pluton, Klamath Mountains, California and Oregon
Robert F. Gribble, Calvin G. Barnes, Mary M. Donato, James D. Hoover, Ronald W. Kistler
1990, Journal of Petrology (31) 883-923
The Ashland pluton is a calc-alkaline plutonic complex that intruded the western Paleozoic and Triassic belt of the Klamath Mountains in late Middle Jurassic time. The pluton comprises a series of compositionally distinct magma pulses. The oldest rocks are hornblende gabbro and two-pyroxene quartz gabbro with initial 87Sr/86Sr = 0˙7044,...
Soil-vegetation correlations in selected wetlands and uplands of North-Central Florida
G. Ronnie Best, Charlotte Wolfe, Debra S. Segal
1990, Report
Vegetation on four hydric and two nonhydric soils series in north-central Florida was sampled as part of a national study examining the correspondence between wetland vegetation and soils. The wetland character of the vegetation was estimated by weighted average calculations using published wetland indicator values for individual plant species....
Water-vapor pressure in nests of the San Miguel Island Song Sparrow
Michael D. Kern, Mark K. Sogge, Charles van Riper III
1990, The Condor (92) 761-767
The water-vapor pressure (PN) in nests of the San Miguel Island race of Song Sparrows (Melospiza melodia micronyx) averaged 16 torr, but varied considerable between nests and within individual nests during successive days of incubation. Large daily fluctuations occurred throughout the incubation period and did not parallel concurrent changes...
On the nature and rate of resurfacing of Venus
Raymond E. Arvidson, Robert E. Grimm, Roger J. Phillips, Gerald G. Schaber, Eugene Merle Shoemaker
1990, Geophysical Research Letters (17) 1385-1388
Crater production and obliteration are modeled for the plains of Venus, using: (1 ) the observed distribution of Venus-crossing asteroids and comets, (2) viscous relaxation of crater topography, and (3) erosion and burial by atmospheric, volcanic, and tectonic processes. Crater lifetimes are assumed to be proportional to...
Energy constraints on kinematic models of oblique faulting: Loma Prieta versus Parkfield-Coalinga
Andrew J. Michael
1990, Geophysical Research Letters (17) 1453-1456
The Loma Prieta earthquake was a combination of right lateral strike-slip and reverse faulting. This oblique motion has been explained by a kinematic model that has the fault accommodate both the translation and convergence required by the Pacific-North American plate motions and a local bend in the San Andreas Fault...
Seismicity in the twenty years preceding the Loma Prieta California Earthquake
Jean A. Olson
1990, Geophysical Research Letters (17) 1429-1432
Persistent seismicity occurred at a low rate during at least the twenty years before the Loma Prieta earthquake along the 60 km-long rupture zone. The depth distribution of this seismicity forms a broad “U”-shape that delineates the previously locked rupture zone. Relocations of seismicity during the ten years before the...
Aseismic slip on the San Andreas Fault south of Loma Prieta
J. Behr, R. Bilham, P. Bodin, Robert O. Burford, R. Bürgmann
1990, Geophysical Research Letters (17) 1445-1448
Two digital creepmeters installed within the San Andreas fault zone after the 18 Oct 1989 Loma Prieta main shock show less than 1 cm of post seismic right-lateral slip in the four months following the earthquake. At Mt. Madonna road a 23 mm coseismic fracture slipped a further 3 mm...
Coseismic stress changes induced by the 1989 Loma Prieta, California Earthquake
Andrew J. Michael, William L. Ellsworth, David H. Oppenheimer
1990, Geophysical Research Letters (17) 1441-1444
Earthquake focal mechanisms from before and after the 1989 Loma Prieta, California earthquake are used to infer the coseismic stress change. Before the main shock, most earthquakes correspond to right lateral slip on planes sub-parallel to the San Andreas fault, and imply a generally N-S most compressional stress axis and...
Seismic slip, segmentation, and the Loma Prieta Earthquake
Geoffrey King, Allan Goddard Lindh, David H. Oppenheimer
1990, Geophysical Research Letters (17) 1449-1452
We have plotted the cumulative seismic slip projected onto a vertical plane for earthquakes occurring during the last 20 years along 210 km of the San Andreas fault that includes the section that moved in the Loma Prieta earthquake. These plots illustrate the differences in depth and character of the...
Development of an aquifer management model AQMAN3D
Juan Carlos Puig, L. I. Rolon-Collazo, Ishmael Pagan-Trinidad
J.H. Krishna, Vicente Quinones-Aponte, Fernando Gomez-Gomez, G.L. Morris, editor(s)
1990, Conference Paper, Tropical hydrology and Caribbean water resources : proceedings of the International Symposium on Tropical Hydrology and Fourth Caribbean Islands Water Resources Congress
A computer code that enables the use of the USGS Modular groundwater flow model for aquifermanagement modeling has been developed. Aquifermanagement techniques integrate groundwater flow modeling with linear quadratic optimization methods for the solution of various aquifer management problems. The model AQMAN3D, is a modified version of a previously developed two-dimensional AQMAN <span...
Measurement of in situ rates of selenate removal by dissimilatory bacterial reduction in sediments
Ronald S. Oremland, Nisan A. Steinberg, Ann S. Maest, Laurence G. Miller, James T. Hollibaugh
1990, Environmental Science & Technology (24) 1157-1164
A radioisotope method for measurement of bacteria respiratory reduction of selenate to elemental selenium in aquatic sediments was devised. Sediments were labeled with [75Se]selenate, incubated, and washed, and 75Se0(s) was determined as counts remaining in the sediments. Core profiles of selenate reduction, sulfate reduction, and denitrification were made simultaneously in...
Landslide processes in saprolitic soils of a tropical rain forest, Puerto Rico
Matthew C. Larsen, Andrew Simon
D. K. Larue, G. Draper, editor(s)
1990, Conference Paper, Transactions of the 12th Caribbean Geological Conference
Shallow soil slips, earth and debris slides appear to be a primary mechanism of hillslope denudation in the rainforest of eastern Puerto Rico. Annual rainfall in excess of 4,000 mm, and thick sequences (up to 20 m) of residual soils (saprolite) combine to produce these landslides. Shear strength testing and...
Rainfall-soil moisture relations in landslide-prone areas of a tropical rain forest, Puerto Rico
Matthew C. Larsen, Angel J. Torres-Sanchez
J.H. Krishna, Vicente Quinones-Aponte, Fernando Gomez-Gomez, G.L. Morris, editor(s)
1990, Conference Paper, Tropical Hydrology and Caribbean Water Resources, Proceedings of the International Symposium on Tropical Hydrology
Soil moisture conditions are not well documented in steep, tropical landslide-prone terrain. In the 11,330 ha Caribbean National Forest (CNF) in northeastern Puerto Rico more than 170 landslides that occurred from one to approximately 60 years ago have been mapped. Most of these landslides are shallow, with failure depths of...
Natural occurrence of silicon carbide in a diamondiferous kimberlite from Fuxian
I. Leung, W. Guo, I. Friedman, J. Gleason
1990, Nature (346) 352-354
Considerable debate surrounds the existence of silicon carbide in nature, mostly owing to the problem of possible contamination by man-made SiC. Recently, Gurney1 reviewed reports of rare SiC inclusions in diamonds, and noted that SiC can only be regarded as a probable rather than proven cogenetic mineral. Here we report our...
Midwestern Holocene paleoenvironments revealed by floodplain deposits in northeastern Iowa
C. A. Chumbley, R. G. Baker, E. Arthur Bettis III
1990, Science (249) 272-274
Pollen analysis of pond deposits in the upper reaches of a stream from northeastern Iowa, an area beyond the last glacial margin, provides a nearly complete record of vegetational changes during the last 12.5 thousand years. Sixty-one radiocarbon dates provide good chronological control. Spruce forest was replaced by deciduous forest...
Liquefaction and foundation failure of Chevron oil and gasoline tanks at Moss Landing, California
Martitia Tuttle, Patience Cowie, John Tinsley, Michael Benett, John Berrill
1990, Geophysical Research Letters (17) 1797-1800
Liquefaction of gray, coarse‐ to medium‐grained, esturine sand during the October 17, 1989 Loma Prieta (Ms=7.1) earthquake led to foundation failures of oil and tanks at the Chevron Marine Station at Moss Landing located about 25 km south‐southeast of the epicenter. Differential settlement of the foundations resulted in 1° to...
Polymerase chain reaction (PCR) amplification of a nucleoprotein gene sequence of infectious hematopoietic necrosis virus
C.K. Arakawa, R.E. Deering, K.H. Higman, K.H. Oshima, P.J. O’Hara, J. R. Winton
1990, Diseases of Aquatic Organisms (8) 165-170
The polymerase chain reaction [PCR) was used to amplify a portion of the nucleoprotein [NI gene of infectious hematopoietic necrosis virus (IHNV). Using a published sequence for the Round Butte isolate of IHNV, a pair of PCR pnmers was synthesized that spanned a 252 nucleotide region of the N gene...
Recent trends in counts of migrant hawks from northeastern North America
Kimberly Titus, Mark R. Fuller
1990, Journal of Wildlife Management (54) 463-470
Using simple regression, pooled-sites route-regression, and nonparametric rank-trend analyses, we evaluated trends in counts of hawks migrating past 6 eastern hawk lookouts from 1972 to 1987. The indexing variable was the total count for a season. Bald eagle (Haliaeetus leucocephalus), peregrine falcon (Falco peregrinus), merlin (F. columbarius), osprey (Pandion haliaetus),...
Habitat use by postfledging American black ducks in Maine and New Brunswick
Catherine Frazer, Jerry R. Longcore, Daniel G. McAuley
1990, Journal of Wildlife Management (54) 451-459
We examined habitat use by 112 postfledging American black ducks (Anas rubripes) in eastern Maine and southwestern New Brunswick from September through early December of 1985, 1986, and 1987. Ducks were captured on Moosehorn National Wildlife Refuge (NWR), Maine. Palustrine Emergent Wetland was the most preferred habitat type. Riverine habitats...
Using 222Rn to examine groundwater/surface discharge interaction in the Rio Grande de Manati, Puerto Rico
K. Kelly Ellins, A. Roman-Mas, A. Lee
1990, Journal of Hydrology (115) 319-341
222Rn was used in the karst drainage basin of the Rio Grande de Manati in Puerto Rico to study groundwater/surface flow relationships. Locations of groundwater influx along two sections of the Rio Grande de Manati were identified. The 222Rn measurements were used together with stream discharge data in a mass balance...
Brunhes chron excursion/polarity episode recorded during the late pleistocene, Albuquerque Volcanoes, New Mexico, USA
J. W. Geissman, L. Brown, B. D. Turrin, L. D. McFadden, S. S. Harlan
1990, Geophysical Journal International (102) 73-88
All basaltic lava flows of the Albuquerque Volcanoes (lat.: 35.2°N, long.: 253.2°E), Albuquerque-Belen Basin, New Mexico, record a short excursion/polarity episode. K-Ar isotopic age determinations (weighted average: 155 ± 47 ka) and evaluation of soil profiles on flow surfaces suggest the late Pleistocene (circa between 250 and 80 ka) as the...
Winter use of douglas-fir forests by Blue Grouse in Colorado
Brian S. Cade, Richard W. Hoffman
1990, Journal of Wildlife Management (54) 471-479
We studied winter use of Douglas-fir (Pseudotsuga menziesii) forests by blue grouse (Dendragapus obscurus) from 1981 to 1983 at 2 study areas in northcentral Colorado. Comparisons of used and available stands indicated grouse were concentrated spatially, but there were no consistent differences related to basal area of tree species, conifer...
Source characteristics of the Loma Prieta, California, Earthquake of October 18, 1989 from global digital seismic data
George Choy, John Boatwright
1990, Geophysical Research Letters (17) 1183-1186
Displacement, velocity and acceleration records of P and SH body waves recorded at teleseismic distances are analysed to determine the static and dynamic source parameters of the Loma Prieta, California earthquake of October 18, 1989 (mb 6.6, Ms 7.1). Three distinct bursts of energy corresponding to three subevents can be recognized in most...
Preliminary velocity and resistivity models of the Loma Prieta Earthquake region
Donna Eberhart-Phillips, Victor F. Labson, William D. Stanley, Andrew J. Michael, Brian D. Rodriguez
1990, Geophysical Research Letters (17) 1235-1238
A preliminary three-dimensional velocity model of the Loma Prieta epicentral region in the Santa Cruz Mountains of California has been derived using raypaths from aftershocks recorded by the U.S.G.S. seismic network. In addition, a magnetotelluric sounding profile was completed prior to the earthquake and a two-dimensional resistivity model computed. The...
Seismomagnetic effect generated by the October, 1989, ML, 7.1 Loma Prieta, California, Earthquake
R.J. Mueller, M.J.S. Johnston
1990, Geophysical Research Letters (17) 1231-1234
A differentially connected array of proton magnetometers operated within the epicentral region of the October 18, 1989, ML 7.1 Loma Prieta earthquake for 12 years from 1974 to 1986. The closest magnetometer station was located 7.3 km from the epicenter of the earthquake and within 3 km of the site where...
