An earthquake instability model based on faults containing high fluid-pressure compartments
D.A. Lockner, J.D. Byerlee
1995, Pure and Applied Geophysics PAGEOPH (145) 717-745
It has been proposed that large strike-slip faults such as the San Andreas contain water in seal-bounded compartments. Arguments based on heat flow and stress orientation suggest that in most of the compartments, the water pressure is so high that the average shear strength of the fault is less than...
Structural controls of Holocene reactivation of the Meers fault, southwestern Oklahoma, from magnetic studies
M. Jones-Cecil
1995, Geological Society of America Bulletin (107) 98-112
Holocene reactivation of the aseismic Meers fault in southwestern Oklahoma illustrates the limitation of using the historical seismic record for identifying hazardous faults in the central United States. The 26- to 37-km-long fault scarp is one of the few known scamps recording Holocene movement in the central and eastern United...
Variations of weekly atmospheric deposition for multiple collectors at a site on the shore of Lake Okeechobee, Florida
N.E. Peters, R.S. Reese
1995, Atmospheric Environment (29) 179-187
Eight wet/dry precipitation collectors were modified to house four additional dryfall collectors and one bulk precipitation collector to sample atmospheric deposition for 12 weeks in a small area on the southwestern shore of Lake Okeechobee; sample contamination, primarily by insects, reduced the comparison to the last nine weeks. The deposition...
Slug tests in unconfined formations: An assessment of the bouwer and rice technique
Z. Hyder, J.J. Butler Jr.
1995, Groundwater (33) 16-22
The slug test is one of the most common techniques for the in situ estimation of hydraulic conductivity in unconfined flow systems. Recently, a mathematical model describing the flow of ground water in response to a slug test in an unconfined flow system has been...
Fluid-inclusion evidence for past temperature fluctuations in the Kilauea East Rift Zone geothermal area, Hawaii
Keith E. Bargar, Terry E.C. Keith, Frank A. Trusdell
1995, Geothermics (24) 639-659
Heating and freezing data were obtained for fluid inclusions in hydrothermal quartz, calcite, and anhydrite from several depths in three scientific observation holes drilled along the lower East Rift Zone of Kilauea volcano, Hawaii. Compositions of the inclusion fluids range from dilute meteoric water to highly modified sea water concentrated...
A summary of the effects of mining and related activities on the sediment-trace element geochemistry of Lake Coeur d'Alene, Idaho, USA
A. J. Horowitz, K. A. Elrick, J. A. Robbins, R.B. Cook
1995, Journal of Geochemical Exploration (52) 135-144
During 1989 and 1990 a series of 12 gravity cores, and 150 surface grab samples were collected in Lake Coeur d'Alene, Idaho to determine trace element concentrations, partitioning and surface and subsurface distribution patterns in the bed sediments of the lake....
Validation of national land-cover characteristics data for regional water-quality assessment
Ronald B. Zelt, Jesslyn F. Brown, M.S. Kelley
1995, Geocarto International (10) 69-80
Land-cover information is used routinely to support the interpretation of water-quality data. The Prototype 1990 Conterminous US Land Cover Characteristics Data Set, developed primarily from Advanced Very High Resolution Radiometer (AVHRR) data, was made available to the US Geological Survey's National Water-Quality Assessment (NAWQA) Program. The study described in this...
Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California
A. S. Davis, S.H. Gunn, W.A. Bohrson, L.-B. Gray, J.R. Hein
1995, Geological Society of America Bulletin (107) 554-570
Compositions of lavas from seven small to medium-sized seamounts, between lat 34.0°N and 30.5°N offshore southern and Baja California, include low-K2O tholeiitic, transitional, and mildly to moderately alkalic basalt and their differentiates. The low-K2O tholeiites resemble primitive (>9% MgO) mid-oceanic-ridge basalt (MORB) with low incompatible element abundances and very depleted,...
Thermodynamics of gas and steam-blast eruptions
L.G. Mastin
1995, Bulletin of Volcanology (57) 85-98
Eruptions of gas or steam and non-juvenile debris are common in volcanic and hydrothermal areas. From reports of non-juvenile eruptions or eruptive sequences world-wide, at least three types (or end-members) can be identified: (1) those involving rock and liquid water initially at boiling-point temperatures (‘boiling-point eruptions’); (2) those powered...
Aerodynamic measurements of methyl bromide volatilization from tarped and nontarped fields
M.S. Majewski, M.M. McChesney, J.E. Woodrow, J.H. Prueger, J.N. Seiber
1995, Journal of Environmental Quality (24) 742-752
Methyl bromide (MeBr) is used extensively in agriculture as a soil fumigant and there is growing concern over the role it may play in the depletion of stratospheric ozone. Methyl bromide is applied using various techniques and very little is known about how much of the...
Optimization techniques for integrating spatial data
U.C. Herzfeld, D. F. Merriam
1995, Mathematical Geology (27) 559-588
Two optimization techniques ta predict a spatial variable from any number of related spatial variables are presented. The applicability of the two different methods for petroleum-resource assessment is tested in a mature oil province of the Midcontinent (USA). The information on petroleum productivity, usually not directly accessible, is related indirectly...
Scour measurements at bridge sites during 1993 Upper Mississippi River Basin flood
David S. Mueller, Mark N. Landers, Edward E. Fischer
1995, Transportation Research Record 47-55
The record flood on the upper Mississippi River basin during the summer of 1993 provided a rare opportunity for collection of data on streambed scour at bridges and for testing of scour data collection equipment under extreme hydraulic conditions. Real-time scour measurements at bridges are categorized into one of three...
Occurrence of active and inactive herbicide ingredients at selected sites in Iowa
W. Wang, M. Liszewski, R. Buchmiller, K. Cherryholmes
1995, Water, Air, & Soil Pollution (83) 21-35
The objective of this study was to investigate the occurrence of herbicide active and inactive ingredients (primarily volatile organic compounds) at four selected sites in Iowa representing drain tiles, observation wells, or lysimeters. Water samples were collected monthly and bi-monthly before and after herbicide applications in 1991, respectively. They...
Pesticides in near-surface aquifers: An assessment using highly sensitive analytical methods and tritium
D.W. Kolpin, D. A. Goolsby, E.M. Thurman
1995, Journal of Environmental Quality (24) 1125-1132
In 1992, the U.S. Geological Survey (USGS) determined the distribution of pesticides in near-surface aquifers of the midwestern USA to be much more widespread than originally determined during a 1991 USGS study. The frequency of pesticide detection increased from 28.4% during the 1991 study to 59.0% during the 1992 study....
Identifying trends in sediment discharge from alterations in upstream land use
R. S. Parker, W. R. Osterkamp
1995, Effects of scale on interpretation and management of sediment and water quality. Proc. symposium, Boulder, 1995 (226) 207-213
Environmental monitoring is a primary reason for collecting sediment data. One emphasis of this monitoring is identification of trends in suspended sediment discharge. A stochastic equation was used to generate time series of annual suspended sediment discharges using statistics from gaging stations with drainage areas between 1606 and 1 805...
Interseismic deformation along the San Andreas Fault in southern California
J.C. Savage, M. Lisowski
1995, Journal of Geophysical Research (100) 12703-12717
Eight trilateration networks located along the San Andreas fault in southern California have been surveyed 8 to 19 times within a 14- to 17-year interval between 1971 and 1992. The data, measurements of distances between the same 10 to 32 pairs of geodetic monuments within a...
Simulation models for conservative and nonconservative solute transport in streams
R.L. Runkel
1995, Effects of scale on interpretation and management of sediment and water quality. Proc. symposium, Boulder, 1995 (226) 153-159
Solute transport in streams is governed by a suite of hydrologic and chemical processes. Interactions between hydrologic processes and chemical reactions may be quantified through a combination of field-scale experimentation and simulation modeling. Two mathematical models that simulate conservative and nonconservative solute transport in streams are presented. A model for...
Radiocarbon ages of pre-bomb clams and the hard-water effect in Lakes Michigan and Huron
David K. Rea, Steven M. Colman
1995, Journal of Paleolimnology (14) 89-91
Five radiocarbon ages, all determined by accelerator mass spectrometry, have been obtained for two pre-bomb bivalves from Lake Michigan and one from Lake Huron. After correcting those ages for the fractionation of14C in calcite and for the radioactively inert CO2 in the atmosphere, we find residual ages, caused by...
Metabolizability and partitioning of energy and protein in green plants by yearling lesser snow geese
James S. Sedinger, Robert G. White, Jerry W. Hupp
1995, The Condor (97) 116-122
We measured apparent metabolizability of organic matter, gross energy, nitrogen and cell wall constituents of pelleted alfalfa by Lesser Snow Geese (Chen caerulescens caerulescens. We also used simultaneous measurements of energy expenditure and apparent metabolizable energy intake to estimate heat increment of feeding and net energy for production and maintenance....
Characterization of a rhabdovirus isolated from carpione Salmo trutta carpio in Italy
G. Bovo, N.J. Olesen, P.E.V. Jorgensen, W. Ahne, J. R. Winton
1995, Diseases of Aquatic Organisms (21) 115-122
A virus, strain 583, was isolated from carpione Salmo trutta carpio fry exhibiting high mortality. The virus was not neutralized by rabbit antisera against the fish rhabdoviruses viral haemorrhagic septicaemia virus (VHSV), infectious hematopoietic necrosis virus, eel rhabdovirus European X, spring viraemia of carp virus or pike fry rhabdovirus, or...
Mission in the works promises precise global topographic data
T. Farr, D. Evans, H. Zebker, D. Harding, J. Bufton, T. Dixon, S. Vetrella, D.B. Gesch
1995, Eos, Transactions, American Geophysical Union (76) 225-229
Significant deficiencies in the quality of today's topographic data severely limit scientific applications. Very few available data sets meet the stringent requirements of 10–30 m for global digital topography and 5 m or better vertical accuracy, and existing satellite systems are unlikely to fulfill these requirements. The Joint Topographic Science...
Mapping the response of riparian vegetation to possible flow reductions in the Snake River, Idaho
W. Carter Johnson, Mark D. Dixon, Robert W. Simons, Susan Jenson, Kevin Larson
1995, Geomorphology (13) 159-173
This study was initiated to determine the general effects of potential flow reductions in the middle Snake River (Swan Falls Dam downstream to the Idaho-Oregon border) on its riparian vegetation. Considerable water from the river is currently used to irrigate the adjacent Snake River Plain, and increased demand for water...
Digital image comparison by subtracting contextual transformations—percentile rank order differentiation
M. E. Wehde
1995, Photogrammetric Engineering and Remote Sensing (61) 1273-1278
The common method of digital image comparison by subtraction imposes various constraints on the image contents. Precise registration of images is required to assure proper evaluation of surface locations. The attribute being measured and the calibration and scaling of the sensor are also important to the validity and interpretability of...
Pinyon-juniper woodlands
Gerald J. Gottfried, Thomas W. Swetnam, Craig D. Allen, Julio L. Betancourt, Alice L. Chung-MacCoubrey
Deborah M. Finch, Joseph A. Tainter, editor(s)
1995, General Technical Report RM-GTR-268-6
Pinyon-juniper woodlands are one of the largest ecosystems in the Southwest and in the Middle Rio Grande Basin (Fig. 1). The woodlands have been important to the region's inhabitants since prehistoric times for a variety of natural resources and amenities. The ecosystems have not been static; their distributions, stand characteristics,...
Assessment of interspecific interactions in plant communities: an illustration from the cold desert saltbush grasslands of North America
Carl D. Freeman, John M. Emlen
1995, Journal of Arid Environments (31) 179-198
Interspecific interactions influence both the productivity and composition of plant communities. Here, we propose new field procedures and analytical approaches for assessing interspecific interactions in nature and apply these procedures to the salt desert shrub grasslands of western Utah. Data were collected from two grazing treatments over a period of...
