Fumarole emissions at Mount St. Helens volcano, June 1980 to October 1981: Degassing of a magma-hydrothermal system
T.M. Gerlach, T. J. Casadevall
1986, Journal of Volcanology and Geothermal Research (28) 141-160
This study is an investigation of the chemical changes in the Mount St. Helens fumarole gases up to October 1981, the sources of the fumarole gases, and the stability of gas species in the shallow magma system. These problems are investigated by calculations of element compositions, thermodynamic equilibria, and magmatic...
Partition coefficients of Hf, Zr, and REE between zircon, apatite, and liquid
H. Fujimaki
1986, Contributions to Mineralogy and Petrology (94) 42-45
Concentration ratios of Hf, Zr, and REE between zircon, apatite, and liquid were determined for three igneous compositions: two andesites and a diorite. The concentration ratios of these elements between zircon and corresponding liquid can approximate the partition coefficient. Although the concentration ratios between apatite and andesite groundmass can be...
Upper mantle structure from teleseismic P wave arrivals in Washington and northern Oregon
C. A. Michaelson, C.S. Weaver
1986, Journal of Geophysical Research Solid Earth (91) 2077-2094
Teleseismic P wave travel time residuals are used to detect lateral velocity heterogeneities in the upper mantle beneath Washington and northern Oregon. The results of an inversion for three-dimensional velocity variations resolves an east dipping high-velocity zone that we interpret as the subducting Juan de Fuca plate. The plate is characterized by...
Tidal reorientation and the fracturing of Jupiter's moon Europa
A. S. McEwen
1986, Nature (321) 49-51
The most striking characteristic of Europa is the network of long linear albedo markings over the surface, suggestive of global-scale tectonic processes. Various explanations for the fractures have been proposed: Freezing and expansion of an early liquid water ocean1, planetary expansion due to dehydration of hydrated silicates2, localization by weak...
Seismically induced landslides: current research by the US Geological Survey.
E. L. Harp, R. C. Wilson, D. K. Keefer, G. F. Wieczorek
1986, Geologia Applicata e Idrogeologia (21) 159-173
We have produced a regional seismic slope-stability map and a probabilistic prediction of landslide distribution from a postulated earthquake. For liquefaction-induced landslides, in situ measurements of seismically induced pore-water pressures have been used to establish an elastic model of pore pressure generation. -from Authors...
Satellite orientation and position for geometric correction of scanner imagery.
P.H. Salamonowicz
1986, Photogrammetric Engineering and Remote Sensing (52) 491-499
The USGS Mini Image Processing System currently relies on a polynomial method for geometric correction of Landsat multispectral scanner (MSS) data. A large number of ground control points are required because polynomials do not model the sources of error. In order to reduce the number of necessary points, a set...
Alternate forms of the associated Legendre functions for use in geomagnetic modeling.
L.R. Alldredge, E.R. Benton
1986, Journal of Geomagnetism & Geoelectricity (38) 599-609
An inconvenience attending traditional use of associated Legendre functions in global modeling is that the functions are not separable with respect to the two indices (order and degree). In 1973 Merilees suggested a way to avoid the problem by showing that associated Legendre functions of order m and degree m+k can be expressed in...
Regression approximations for transport model constraint sets in combined aquifer simulation-optimization studies
William M. Alley
1986, Water Resources Research (22) 581-586
Problems involving the combined use of contaminant transport models and nonlinear optimization schemes can be very expensive to solve. This paper explores the use of transport models with ordinary regression and regression on ranks to develop approximate response functions of concentrations at critical locations as a function of pumping and...
Geochemical evaluation of the geothermal resources in the San Marcos region, Guatemala
R.O. Fournier, B.B. Hanshaw
1986, Applied Geochemistry (1) 189-197
The chemical and isotopic compositions of hot springs in the San Marcos region of Guatemala are internally consistent with a hydrologic model in which a deep 240°C reservoir and one or more shallow 195–200°C reservoirs are present. Variations in hot-spring water...
Adaptation of the Carter-Tracy water influx calculation to groundwater flow simulation
Kenneth L. Kipp
1986, Water Resources Research (22) 423-428
The Carter-Tracy calculation for water influx is adapted to groundwater flow simulation with additional clarifying explanation not present in the original papers. The Van Everdingen and Hurst aquifer-influence functions for radial flow from an outer aquifer region are employed. This technique, based on convolution of unit-step response functions, offers a...
The origin of fluids in the salt beds of the Delaware Basin, New Mexico and Texas
J. R. O’Neil, C.M. Johnson, L. D. White, E. Roedder
1986, Applied Geochemistry (1) 265-271
Oxygen and hydrogen isotope analyses have been made of (1) brines from several wells in the salt deposits of the Delaware Basin, (2) inclusion fluids in halite crystals from the ERDA No. 9 site, and (3) local ground waters of meteoric...
VISCOPLASTIC FLUID MODEL FOR DEBRIS FLOW ROUTING.
Cheng-lung Chen
1986, Conference Paper
This paper describes how a generalized viscoplastic fluid model, which was developed based on non-Newtonian fluid mechanics, can be successfully applied to routing a debris flow down a channel. The one-dimensional dynamic equations developed for unsteady clear-water flow can be used for debris flow routing if the flow parameters, such...
To accrete or not accrete, that is the question
Roland E. von Huene
1986, Geologische Rundschau (75) 1-15
Along modern convergent margins tectonic processes span a spectrum from accretion to erosion. The process of accretion is generally recognized because it leaves a geologic record, whereas the process of erosion is generally hypothetical because it produces a geologic hiatus. Major conditions that determine the dominance of accretion or erosion...
Summary of pre-1980 tephra-fall deposits erupted from Mount St. Helens, Washington State, USA
D. R. Mullineaux
1986, Bulletin of Volcanology (48) 17-26
Mount St. Helens has been a prolific source of tephra-fall deposits for about 40 000 years. These tephra deposits (1) record numerous explosive eruptions, (2) form important regional time-stratigraphic marker beds, and (3) record repeated changes in composition within and between eruptive periods. Recognized tephra strata record more than 100...
A comparison of several methods for the solution of the inverse problem in two-dimensional steady state groundwater flow modeling
Logan K. Kuiper
1986, Water Resources Research (22) 705-714
Two geostatistical approaches for the estimation of hydraulic conductivity and hydraulic head from hydraulic conductivity and hydraulic head measurements are developed for two-dimensional steady flow with sinks. For both approaches the field of the logarithm of hydraulic conductivity (log-conductivity) is represented as a random field with mean θ1+θ2x+θ3y where xand y denote Cartesian coordinates,...
Electrothermal atomisation atomic absorption conditions and matrix modifications for determining antimony, arsenic, bismuth, cadmium, gallium, gold, indium, lead, molybdenum, palladium, platinum, selenium, silver, tellurium, thallium and tin following back-extraction of organic aminohalide extracts
J. R. Clark
1986, Journal of Analytical Atomic Spectrometry (1) 301-308
A multi-element organic-extraction and back-extraction procedure, that had been developed previously to eliminate matrix interferences in the determination of a large number of trace elements in complex materials such as geological samples, produced organic and aqueous solutions that were complex. Electrothermal atomisation atomic absorption conditions and matrix modifications have been...
Application of seismic refraction methods in groundwater modeling studies in New England (USA)
F.P. Haeni
1986, Geophysics (51) 236-249
Seismic refraction studies were conducted over unconfined glacial aquifers in New England to determine: 1) depth of the underlying bedrock; 2) depth of the water table; 3) saturated thickness of the aquifer in areas not accessible to heavy drilling equipment; 4) areas where thick, unsaturated sediments overlie thickly saturated parts...
A ground-water mixing model for the origin of the Imini manganese deposit (Cretaceous) of Morocco
E. R. Force, W. Back, E.C. Spiker, L.P. Knauth
1986, Economic Geology (81) 65-79
Three beds of manganese oxide ore in a 10 m-thick dolomite unit are associated with diagenetic features, and, are accordingly also diagenetic in their present aspect. Whether primary or introduced, the Mn mineralogy is attributed to reactions between fresh and saline ground-waters as the zone of mixing passed through the...
Sr, Nd and Pb isotopes in Proterozoic intrusives astride the Grenville Front in Labrador: Implications for crustal contamination and basement mapping
L.D. Ashwal, J. L. Wooden, R.F. Emslie
1986, Geochimica et Cosmochimica Acta (50) 2571-2585
We report Sr, Nd and Pb isotopic compositions of mid-Proterozoic anorthosites and related rocks (1.45-1.65 Ga) and of younger olivine diabase dikes (1.4 Ga) from two complexes on either side of the Grenville Front in Labrador. Anorthositic or diabasic samples from the Mealy Mountains (Grenville Province) and Harp Lake (Nain-Churchill...
Analysis of thematic map classification error matrices.
G.H. Rosenfield
1986, Photogrammetric Engineering and Remote Sensing (52) 681-686
The classification error matrix expresses the counts of agreement and disagreement between the classified categories and their verification. Thematic mapping experiments compare variables such as multiple photointerpretation or scales of mapping, and produce one or more classification error matrices. This paper presents a tutorial to implement a typical problem of...
Aluminum enrichment in silicate melts by fractional crystallization: some mineralogic and petrographic constraints.
E. Zen
1986, Journal of Petrology (27) 1095-1117
The degree of aluminum saturation of an igneous rock may be described by its Aluminum Saturation Index (ASI) defined as the molar ratio Al2O3(CaO + K2O + Na2O). One suggested origin for mildly peraluminous granites (ASI between 1 and about 1.1) is by fractional crystallization of subaluminous (ASI <...
FASP, an analytic resource appraisal program for petroleum play analysis
R. A. Crovelli, R.H. Balay
1986, Computers & Geosciences (12) 423-475
An analytic probabilistic methodology for resource appraisal of undiscovered oil and gas resources in play analysis is presented in a FORTRAN program termed FASP. This play-analysis methodology is a geostochastic system for petroleum resource appraisal in explored as well as frontier areas. An established geologic model considers both the uncertainty...
ARCTIC SEA ICE EXTENT AND DRIFT, MODELED AS A VISCOUS FLUID.
Chi-Hai Ling, Claire L. Parkinson
1986, Ocean science and engineering (11) 71-98
A dynamic/thermodynamic numerical model of sea ice has been used to calculate the yearly cycle of sea ice thicknesses, concentrations, and velocities in the Arctic Ocean and surrounding seas. The model combines the formulations of two previous models, taking the thermodynamics and momentum equations from the model of Parkinson and...
THERMAL-ENERGY STORAGE IN A DEEP SANDSTONE AQUIFER IN MINNESOTA: FIELD OBSERVATIONS AND THERMAL ENERGY-TRANSPORT MODELING.
R. T. Miller
1986, Conference Paper, Proceedings of the Intersociety Energy Conversion Engineering Conference
A study of the feasibility of storing heated water in a deep sandstone aquifer in Minnesota is described. The aquifer consists of four hydraulic zones that are areally anisotropic and have average hydraulic conductivities that range from 0. 03 to 1. 2 meters per day. A preliminary axially symmetric, nonisothermal,...
The solubility of BaCO3(cr) (witherite) in CO2-H2O solutions between 0 and 90°C, evaluation of the association constants of BaHCO3+(aq) and BaCO30(aq) between 5 and 80°C, and a preliminary evaluation of the thermodynamic properties of Ba2+(aq)
Eurybiades Busenberg, Niel Plummer
1986, Geochimica et Cosmochimica Acta (50) 2225-2233
One hundred and fifty new measurements of the solubility of witherite were used to evaluate the equilibrium constant of the reaction BaCO3(cr) = Ba2+(aq) + CO32−(aq) between 0 and 90°C and 1 atm total pressure. The temperature dependence of the equilibrium constant is given by logK = 607.642 + 0.121098T − 20011.25/T − 236.4948 logT where T is in degrees...
