Solute transport with multisegment, equilibrium-controlled reactions: A feed forward simulation method
Jacob Rubin
1990, Water Resources Research (26) 2029-2055
The feed forward method (FF method) is one of the ways of formulating operational equations which simulate transport of solutes influenced by equilibrium-controlled reaction networks. The FF method provides increased solution efficiency by adapting its formulations to some of the network's fundamental features. In this study the FF method is...
Dark materials in Valles Marineris: Indications of the style of volcanism and magmatism on Mars
Paul E. Geissler, Robert B. Singer, Baerbel K. Lucchitta
1990, Journal of Geophysical Research B: Solid Earth (95) 14.399-14.413
Rifting on the equatorial canyon system of Valles Marineris provides a unique view of the interior of the Martian crust to depths reaching 7 km, exposing several in situ bedrock units which testify to past volcanic and magmatic processes on Mars. A thick, regionally extensive deposit observed in Coprates and...
The use of interactive videodisc in natural resources training
M.M. Banowetz, R.C. Solomon, W.L. Mangus
1990, Book, Proceedings of the Twelfth Annual Conference
No abstract available....
Fire - Southern Oscillation relations in the southwestern United States
T.W. Swetnam, Julio L. Betancourt
1990, Science (249) 1017-1020
Fire scar and tree growth chronologies (1700 to 1905) and fire statistics (since 1905) from Arizona and New Mexico show that small areas burn after wet springs associated with the low phase of the Southern Oscillation (SO), whereas large areas burn after dry springs associated with the high phase of...
Sediment and aquatic habitat associations in river systems
Robert T. Milhous, R.C. MacArthur, F.D. Shields Jr., J.R. Adams
1990, Book, Proceedings of the 1990 National Conference: Results from the ASCE Task Committee on sediment transport and aquatic habitats
No abstract available....
Questions on habitat preference
J.M. Bartholow, W. Slauson, Bradford G.M. Parsons, Wayne A. Hubert
1990, North American Journal of Fisheries Management (10) 362-363
No abstract available....
Sterilizing effects of cobalt-60 and cesium-137 radiation on male sea lampreys
L.H. Hanson
1990, North American Journal of Fisheries Management (10) 352-361
Male spawning-run sea lampreys Petromyzon marinus were exposed to various doses of cobalt-60 or cesium-137 radiation in an attempt to sterilize them for use in a program for controlling sea lampreys through the release of sterile males. Males captured and irradiated during the early part of the upstream migration were...
Flume experiments on the alignment of transverse, oblique, and longitudinal dunes in directionally varying flows
David M. Rubin, Hiroshi Ikeda
1990, Sedimentology (37) 673-684
For more than a century geologists have wondered why some bedforms are orientated roughly transverse to flow, whereas others are parallel or oblique to flow. This problem of bedform alignment was studied experimentally using subaqueous dunes on a 3–6-m-diameter sand-covered turntable on the floor of a 4-m-wide flume.In each experiment,...
Human impacts on bear habitat use
David J. Mattson
1990, Bears: Their Biology and Management (8) 33-56
: Human effects on bear habitat use are mediated through food biomass changes, bear tolerance of humans and their impacts, and human tolerance of bears. Large-scale changes in bear food biomass have been caused by conversion of wildlands and waterways to intensive human use, and by the introduction of exotic...
The October 17, 1989, Loma Prieta, California, Earthquake and its aftershocks: Geometry of the sequence from high-resolution locations
Lynn D. Dietz, William L. Ellsworth
1990, Geophysical Research Letters (17) 1417-1420
Hypocenters of the Loma Prieta sequence form a dipping zone that rises from the mainshock hypocenter and is parallel to the mainshock nodal plane. Most aftershocks cluster around the perimeter of the zone, surrounding a relatively aseismic center which approximates the region of mainshock rupture. At its southeastern end, the...
Regional water quality
Janet Hren, Carolyn J. Oblinger Childress, J. Michael Norris, Thomas H. Chaney, Donna N. Myers
1990, Environmental Science and Technology (24) 1122-1127
No abstract available....
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...
Field trip guide - American Water Resources Association
Matthew C. Larsen, Thalia D. Veve
1990, Conference Paper, International Symposium on Tropical Hydrology and Fourth Caribbean Islands Water Resources Congress
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...
