Experimental oxygen isotope fractionation between siderite-water and phosphoric acid liberated CO2-siderite
W.W. Carothers, L.H. Adami, R.J. Rosenbauer
1988, Geochimica et Cosmochimica Acta (52) 2445-2450
The equilibrium fractionation of O isotopes between synthetic siderite and water has been measured at temperatures ranging from 33° to 197°C. The fractionation between siderite and water over this temperature range can be represented by the equation: 103 ln α = 3.13 × 106T−2 −...
Assimilation of granite by basaltic magma at Burnt Lava flow, Medicine Lake volcano, northern California: Decoupling of heat and mass transfer
T.L. Grove, R.J. Kinzler, M. B. Baker, J.M. Donnelly-Nolan, C.E. Lesher
1988, Contributions to Mineralogy and Petrology (99) 320-343
At Medicine Lake volcano, California, andesite of the Holocene Burnt Lava flow has been produced by fractional crystallization of parental high alumina basalt (HAB) accompanied by assimilation of granitic crustal material. Burnt Lava contains inclusions of quenched HAB liquid, a potential parent magma of the andesite, highly melted granitic crustal...
High-resolution 40Ar 39Ar chronology of Oligocene volcanic rocks, San Juan Mountains, Colorado
M. A. Lanphere
1988, Geochimica et Cosmochimica Acta (52) 1425-1434
The central San Juan caldera complex consists of seven calderas from which eight major ash-flow tuffs were erupted during a period of intense volcanic activity that lasted for approximately 2 m.y. about 26–28 Ma. The analytical precision of conventional K-Ar dating in this time interval is not sufficient to unambiguously...
The metal oxide fraction of pelagic sediment in the equatorial North Pacific Ocean: A source of metals in ferromanganese nodules
D.Z. Piper
1988, Geochimica et Cosmochimica Acta (52) 2127-2145
Pelagic sediment recovered at DOMES Site A in the equatorial North Pacific (151°W, 9° 15′N) consists of a surface homogeneous layer, approximately 10 cm thick, overlying a strongly mottled layer that is lighter in color. The radiolarian composition of both units is Quaternary. In areas where this sediment was only...
Fluid inclusions in vadose cement with consistent vapor to liquid ratios, Pleistocene Miami Limestone, southeastern Florida
C.E. Barker, R. B. Halley
1988, Geochimica et Cosmochimica Acta (52) 1019-1025
Vadose cements in the Late Pleistocene Miami Limestone contain regions with two-phase aqueous fluid inclusions that have consistent vapor to liquid (V-L) ratios. When heated, these seemingly primary inclusions homogenize to a liquid phase in a range between 75°C and 130°C (mean = 100°C) and have final melting temperatures between...
Effects of kelp forest removal on associated fish assemblages in central California
James L. Bodkin
1988, Journal of Experimental Marine Biology and Ecology (117) 227-238
Visual surveys along subtidal belt transects were used to compare fish assemblages on an experimental and a control site before and after the removal of a canopy-forming kelp forest. The giant kelp Macrocystis pyrifera (L.) C.A. Agardh was removed at the holdfast from ≈ 1 ha of high relief structurally complex rock...
Normalization of oxygen and hydrogen isotope data
T.B. Coplen
1988, Chemical Geology: Isotope Geoscience Section (72) 293-297
To resolve confusion due to expression of isotopic data from different laboratories on non-corresponding scales, oxygen isotope analyses of all substances can be expressed relative to VSMOW or VPDB (Vienna Peedee belemnite) on scales normalized such that the δ18O of SLAP is −55.5% relative to VSMOW.H3+ contribution in hydrogen isotope ratio analysis can...
Short-term trends in sulfate deposition at selected bulk precipitation stations in New York
R.M. Hirsch, N.E. Peters
1988, Atmospheric Environment (22) 1175-1178
Trends in rainfall-adjusted sulfate concentration were assessed for 5-yr subrecords of the 14.5–17 yr of monthly bulk-deposition data from five stations in New York by using the seasonal Kendall test. For the 5-yr subrecord from 1978 to 1982, the trends for the bulk deposition were similar to those for weekly...
Composition of massive sulfide deposits from the sediment-covered floor of Escanaba Trough, Gorda Ridge: implications for depositional processes
Randolph A. Koski, Wayne C. Shanks III, Wendy A. Bohrson, Robert L. Oscarson
1988, Canadian Mineralogist (26 pt 3) 655-673
Massive sulfide deposits with two distinct compositions are spatially related to volcanic edifices that penetrate up to 500 m of turbiditic sediment in Escanaba Trough (ET), southern Gorda Ridge. The mineralogy, metal content, sulfur isotope composition, and hydrocarbon content of massive sulfides from ET reflect the extensive interaction between underlying...
Composition and stable-isotope geochemistry of natural gases from Kansas, Midcontinent, U.S.A.
P.D. Jenden, K.D. Newell, I.R. Kaplan, W.L. Watney
1988, Chemical Geology (71) 117-147
More than 28??1012 ft.3 (79??1010 m3) of natural gas and 5.3??109 bbl (8.4??108 m3) of oil have been produced in Kansas, U.S.A., from Paleozoic carbonate and sandstone reservoirs on structural uplifts and shallow embayments along the northern margin of the Anadarko basin. A heavily-explored, geologically well-characterized state, Kansas is an...
Retardations in fault creep rates before local moderate earthquakes along the San Andreas fault system, central California
Robert O. Burford
1988, Pure and Applied Geophysics PAGEOPH (126) 499-529
Records of shallow aseismic slip (fault creep) obtained along parts of the San Andreas and Calaveras faults in central California demonstrate that significant changes in creep rates often have been associated with local moderate earthquakes. An immediate postearthquake increase followed by gradual, long-term decay back to a previous background rate...
Federal microcomputer software for urban hydrology
Marshall E. Jennings, Roger H. Smith, Ross B. Jennings
1988, Conference Paper
The purpose of this paper is to describe the development, availability, and general use of selected urban hydrology microcomputer software developed by: U.S. Soil Conservation Service (SCS); U.S. Army Corps of Engineers, Hydrologic Engineering Center (HEC); U.S. Environmental Protection Agency (EPA); and U.S. Geological Survey (USGS). The discussion is limited...
Hydraulic fracturing in situ stress measurements to 2.1 km depth at Cajon Pass, California
J. H. Healy, Mark D. Zoback
1988, Geophysical Research Letters (15) 1005-1008
Stress measurements to 2.1 km reveal stress changes with depth that cannot be explained by an elastic response to uniform crustal strain. The data at about 1 km depth suggest that the stress is limited by the frictional strength of rock and is perturbed at greater...
Quarterly Wildlife Mortality Report July 1987- September 1987
K. A. Converse, R. Windingstad, J. C. Franson, T. Roffe
1988, Wildlife Disease Newsletter (24)
No abstract available....
Correlation diagrams in 40 Ar/39Ar dating: is there a correct choice?
G. B. Dalrymple, M. A. Lanphere, M. S. Pringle
1988, Geophysical Research Letters (15) 589-591
Contrary to published assertions, the two types of correlation diagrams used in the interpretation of 40Ar/39Ar incremental-heating data yield the same information provided the correct mathematics are used for estimating correlation coefficients and for the least squares fit. The choice is simply between two illustrative, graphical displays,...
Elastic-wave propagation and site amplification in the Salt Lake Valley, Utah, from simulated normal faulting earthquakes
H.M. Benz, R. B. Smith
1988, Bulletin of the Seismological Society of America (78) 1851-1874
The two-dimensional seismic response of the Salt Lake valley to near- and far-field earthquakes has been investigated from simulations of vertically incident plane waves and from normal-faulting earthquakes generated on the basin-bounding Wasatch fault. The response to normal faulting earthquakes was simulated using a two-dimensional finite-element method and the plane-wave...
Generalized viscoplastic modeling of debris flow
Cheng-lung Chen
1988, Journal of Hydraulic Engineering (114) 237-258
Various concepts have been proposed or used in the development of Theological models for debris flow. The earliest model developed by Bagnold was based on the concept of the “dispersive” pressure generated by grain collisions. Bagnold's concept appears to be theoretically sound, but his empirical model has been found to...
The surface integral approach to Radarclinometry
R.L. Wildey
1988, Earth, Moon and Planets (41) 141-153
Because radarclinometry is fundamentally describable in terms of a nonlinear, first-order, partial differential equation, one expects that it can, in principle, be carried out by direct deterministic integration beginning at a given threshold profile along the azimuthal coordinate. Such a boundary condition could be provided by the altimetry profile obtained...
Paleoecology of Middle Pennsylvanian-age peat-swamp plants in Herrin coal, Kentucky, U.S.A.
R.B. Winston
1988, International Journal of Coal Geology (10) 203-238
To develop a method for quantifying the vegetation of Pennsylvania-age coal beds, of four coal-ball (permineralized peat) profiles and four coal column samples from the Herrin coal bed (Kentucky No. 11) Carbondale Formation in western Kentucky were compared. An estimated 89.5%...
Three decades of geochronologic studies in the New England Appalachians
R. E. Zartman
1988, Geological Society of America Bulletin (100) 1168-1180
Over the past 30 years, both isotope geochronology and plate tectonics grew from infancy into authoritative disciplines in the geological sciences. Previously, mountain systems like the Appalachians had been viewed almost entirely in the context of the classical geosyncline, implying a gradualism in stratigraphic and structural change throughout the orogen....
Stable isotope geochemistry of sphalerite and other mineral matter in coal beds of the Illinois and Forest City basins
J. F. Whelan, J.C. Cobb, R. O. Rye
1988, Economic Geology (83) 990-1007
Cleat and clastic dikes of Middle Pennsylvanian-age coal beds of the Illinois and Forest City basins of Illinois, Iowa, Missouri, and Kansas locally contain appreciable amounts of sphalerite within a kaolinite-pyrite-sphalerite (+ or - pyrite)-calcite paragenetic sequence. The sphalerite and associated minerals are of interest as a partial record of...
Conductive heat flux in VC-1 and the thermal regime of Valles caldera, Jemez Mountains, New Mexico
J.H. Sass, P. Morgan
1988, Journal of Geophysical Research Solid Earth (93) 6027-6039
Over 5% of heat in the western United States is lost through Quaternary silicic volcanic centers, including the Valles caldera in north central New Mexico. These centers are the sites of major hydrothermal activity and upper crustal metamorphism, metasomatism, and mineralization, producing associated geothermal resources. We present new heat flow...
The global distribution, abundance, and stability of SO2 on Io
A. S. McEwen, T. V. Johnson, D. L. Matson, L.A. Soderblom
1988, Icarus (75) 450-478
Sulfur dioxide distribution and abundances, bolometric hemispheric albedos, and passive surface temperatures on Io are modeled and mapped globally from Voyager multispectral mosaics, Earth-based spectra, and photometric descriptions. Photometric models indicate global average values for regolith porosity of 75-95% and macroscopic roughness with a mean slope angle of ~30??. Abundances...
Power formula for open-channel flow resistance
Cheng-lung Chen
1988, Conference Paper
This paper evaluates various power formulas for flow resistance in open channels. Unlike the logarithmic resistance equation that can be theoretically derived either from Prandtl's mixing-length hypothesis or von Karman's similarity hypothesis, the power formula has long had an appearance of empiricism. Nevertheless, the simplicity in the form of the...
Asymptotic Rayleigh instantaneous unit hydrograph
B.M. Troutman, M.R. Karlinger
1988, Stochastic Hydrology and Hydraulics (2) 73-78
The instantaneous unit hydrograph for a channel network under general linear routing and conditioned on the network magnitude, N, tends asymptotically, as N grows large, to a Rayleigh probability density function. This behavior is identical to that of the width function of the network, and is proven under the assumption...
