Coupling of ocean bottom seismometers to sediment: Results of tests with the U.S. Geological Survey ocean bottom seismometer
Anne M. Trehu
1985, Bulletin of the Seismological Society of America (75) 271-289
The response of an ocean bottom seismometer (OBS) to a transient pull that excites the natural OBS-sediment coupling resonance can be modeled as a mass-spring-dashpot system in which the resonant frequency and damping are functions of instrument mass and bearing radius and of the physical properties of the sediment (primarily...
Prediction of central California earthquakes from soil-gas helium fluctuations
G.M. Reimer
1985, Pure and Applied Geophysics PAGEOPH (122) 369-375
The observations of short-term decreases in helium soil-gas concentrations along the San Andreas Fault in central California have been correlated with subsequent earthquake activity. The area of study is elliptical in shape with radii approximately 160??80 km, centered near San Benito, and with the major axis parallel to the Fault....
Scientific knowledge and modern prospecting
G. J. Neuerburg
1985, Mineralium Deposita (20) 30-32
Modern prospecting is the systematic search for specified and generally ill-exposed components of the Earth's crust known as ore. This prospecting depends entirely on reliable, or scientific knowledge for guidance and for recognition of the search objects. Improvement in prospecting results from additions and refinements to scientific knowledge. Scientific knowledge...
An assessment of the near-surface accuracy of the international geomagnetic reference field 1980 model of the main geomagnetic field
N.W. Peddie, A.K. Zunde
1985, Physics of the Earth and Planetary Interiors (37) 1-4
The new International Geomagnetic Reference Field (IGRF) model of the main geomagnetic field for 1980 is based heavily on measurements from the MAGSAT satellite survey. Assessment of the accuracy of the new model, as a description of the main field near the Earth's surface, is important because the accuracy of...
Application of the 1:2,000,000-scale data base: A National Atlas sectional prototype
Donna M. Dixon
1985, Conference Paper, Technical Papers of the American Congress of Surveying and Mapping
A study of the potential to produce a National Atlas sectional prototype from the 1:2,000,000-scale data base was concluded recently by the National Mapping Division, U. S. Geological Survey. This paper discusses the specific digital cartographic production procedures involved in the preparation of the prototype map, as well as the...
Trondhjemite and metamorphosed quartz keratophyre tuff of the Ammonoosuc volcanics (Ordovician), western New Hampshire and adjacent Vermont and Massachusetts
G. W. Leo
1985, Geological Society of America Bulletin (96) 1493-1507
The Ammonoosuc Volcanics and equivalent rocks of Ordovician age are exposed in the Oliverian domes along the Bronson Hill anti-clinorium (BHA) between northern New Hampshire and southern Connecticut. In western New Hampshire and adjacent Vermont and Massachusetts, the Ammonoosuc lithology consists of a...
Degradation of carbohydrates and lignins in buried woods
J. I. Hedges, G.L. Cowie, J.R. Ertel, Barbour R. James, Patrick G. Hatcher
1985, Geochimica et Cosmochimica Acta (49) 701-711
Spruce, alder, and oak woods deposited in coastal sediments were characterized versus their modern counterparts by quantification of individual neutral sugars and lignin-derived phenols as well as by scanning electron microscopy, 13C NMR, and elemental analysis. The buried spruce wood from a 2500 yr old deposit was unaltered whereas an alder wood from...
Modeling the rate-controlled sorption of hexavalent chromium
D.B. Grove, Kenneth G. Stollenwerk
1985, Water Resources Research (21) 1703-1709
Sorption of chromium VI on the iron-oxide- and hydroxide-coated surface of alluvial material was numerically simulated with rate-controlled reactions. Reaction kinetics and diffusional processes, in the form of film, pore, and particle diffusion, were simulated and compared with experimental results. The use of empirically calculated rate coefficients for diffusion through...
Franciscan complex calera limestones: Accreted remnants of farallon plate oceanic plateaus
J.A. Tarduno, M. McWilliams, M.G. Debiche, W.V. Sliter, M.C. Blake
1985, Nature (317) 345-347
The Calera Limestone, part of the Franciscan Complex of northern California, may have formed in a palaeoenvironment similar to Hess and Shatsky Rises of the present north-west Pacific1. We report here new palaeomagnetic results, palaeontological data and recent plate-motion models that reinforce this assertion. The Calera Limestone may have formed...
Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850
R. J. Spencer, H.P. Eugster, B.F. Jones, S.L. Rettig
1985, Geochimica et Cosmochimica Acta (49) 727-737
The hydrochemistry of Great Salt Lake, Utah, has been defined for the historic period, 1850 through 1982, from published data combined with new observations. The water balance depends largely on river inflow, atmospheric precipitation onto the lake surface and evaporation. Input of the major solutes can best be accounted for...
Mallard recruitment in the agricultural environment of North Dakota
L.M. Cowardin, D.S. Gilmer, Charles W. Shaiffer
1985, Wildlife Monographs (92) 3-37
Recruitment of a mallard (Anas platyrhynchos) population was assessed on a 10,041-km2 study area in central North Dakota during 1977-80. We equipped 338 hens with radio transmitters and monitored them during the breeding season. Two hundred thirty-five of these hens furnished data reported here. Habitat use, nest site selection, fate...
Linear inversion of transmitted acoustic wave fields for three-dimensional modulus and density perturbations using a born-type approximation
Douglas A. Stauber
1985, Bulletin of the Seismological Society of America (75) 93-114
A Born approximation is used to linearize the relationship, in the horizontal-wavenumber and frequency domains, between lateral perturbations of modulus and density in a layered half-space and the acoustic wave field observed at the surface when a plane wave is incident from below. The resulting equations can be used to...
Carboniferous paleogeographic, phytogeographic, and paleoclimatic reconstructions
D.B. Rowley, A. Raymond, Judith T. Parrish, A.L. Lottes, C.R. Scotese, A.M. Ziegler
1985, International Journal of Coal Geology (5) 7-42
Two revised paleogeographic reconstructions of the Visean and Westphalian C-D stages are presented based on recent paleomagnetic, phytogeographic, stratigraphic, and tectonic data. These data change the positions of some continental blocks, and allow the definition of several new ones. The most...
Geometric accuracy of Landsat-4 and Landsat-5 Thematic Mapper images.
W.T. Borgeson, R. M. Batson, H. H. Kieffer
1985, Photogrammetric Engineering and Remote Sensing (51) 1893-1898
The geometric accuracy of the Landsat Thematic Mappers was assessed by a linear least-square comparison of the positions of conspicuous ground features in digital images with their geographic locations as determined from 1:24 000-scale maps. For a Landsat-5 image, the single-dimension standard deviations of the standard digital product, and of...
Subtidal sea level and current variations in the northern reach of San Francisco Bay
R. A. Walters, J. W. Gartner
1985, Estuarine, Coastal and Shelf Science (21) 17-32
Analyses of sea level and current-meter data using digital filters and a variety of statistical methods show a variety of phenomena related to non-local coastal forcing and local tidal forcing in the northern reach of San Francisco Bay, a partially mixed estuary. Low-frequency variations in sea level are dominated by...
Three-dimensional trend mapping from wire-line logs
J.H. Doveton, Z. Ke-an
1985, Journal of the International Association for Mathematical Geology (17) 485
Mapping of lithofacies and porosities of stratigraphic units is complicated because these properties vary in three dimensions. The method of moments was proposed by Krumbein and Libby (1957) as a technique to aid in resolving this problem. Moments are easily computed from wireline logs and are simple statistics which summarize...
Germanium geochemistry and mineralogy
L.R. Bernstein
1985, Geochimica et Cosmochimica Acta (49) 2409-2422
Germanium is enriched in the following geologic environments:1.(1) iron meteorites and terrestrial iron-nickel;2.(2) sulfide ore deposits, particularly those hosted by sedimentary rocks;3.(3) iron oxide deposits;4.(4) oxidized zones of Ge-bearing sulfide deposits;5.(5) pegmatites, greisens, and skarns; and6.(6) coal...
A nomogram for interpreting slope stability of fine-grained deposits in modern and ancient-marine environments.
J.S. Booth, D.A. Sangrey, J.K. Fugate
1985, Journal of Sedimentary Petrology (55) 29-36
Design of the nomogram is based on effective stress and combines consolidation theory as applicable to depositional environments with the infinite-slope model of slope-stability analysis. The link between the two combined theories is a term representing the effective overburden stress, which may be...
SENSITIVITY OF STRUCTURAL RESPONSE TO GROUND MOTION SOURCE AND SITE PARAMETERS.
Erdal Safak
C.A. Brebbia, A.S. Cakmak, Abdel Ghaffar, editor(s)
1985, Conference Paper
Designing structures to withstand earthquakes requires an accurate estimation of the expected ground motion. While engineers use the peak ground acceleration (PGA) to model the strong ground motion, seismologists use physical characteristics of the source and the rupture mechanism, such as fault length, stress drop, shear wave velocity, seismic moment,...
Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout
P. F. Woods
1985, Water-Resources Investigations Report 85-4292
The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area < 25 sq hectometers) lakes in the Matanuska-Susitna Borough. The project goal was to develop empirical models for predicting rainbow trout growth rates from the following variables: total...
Use of strontium isotopes to constrain the timing and mode of dolomitization of upper Cenozoic sediments in a core from San Salvador, Bahamas
Peter K. Swart, Joaquin Ruiz, Charles W. Holmes
1985, Geology (15) 262-265
The 87Sr/86Sr ratios and the activity ratios of 234U/238U and 230Th/238U have been measured in dolomites from a 168-m-deep core taken on the island of San Salvador, Bahamas. These data suggest two periods of dolomitization. The first episode dolomitized Miocene age sediments during the latest Miocene, and the second dolomitized the Pliocene portion...
Ice-lubricated gravity spreading of the Olympus Mons aureole deposits
K. L. Tanaka
1985, Icarus (62) 191-206
Gravity sliding and spreading at low strain rates can account for the general morphology and structure of the aureoles and basal scarp of Olympus Mons. Detachment sliding could have occurred around the volcano if either pore-fluid pressures were exceptionally high (greater than 90%) or the rocks had very low resistance...
Improving waterfowl production estimates: Results of a test in the prairie pothole region
P.M. Arnold, L.M. Cowardin
1985, International Congress of Game Biologists (17) 859-865
The U.S. Fish and Wildlife Service in an effort to improve and standardize methods for estimating waterfowl production tested a new technique in the four-county Arrowwood Wetland Management District (WMD) for three years (1982-1984). On 14 randomly selected 10.36 km2 plots, upland and wetland habitat was mapped, classified, and digitized....
Carboniferous U-Pb age of the Sebago batholith, southwestern Maine: Metamorphic and tectonic implications
J.H. Aleinikoff, R. H. Moench, J.B. Lyons
1985, Geological Society of America Bulletin (96) 990-996
Two phases (pink and white granite) of the Sebago batholith of southwestern Maine have been dated by the U-Pb zircon method. Identical upper concordia intercepts of both rocks indicate an intrusive age of 325 ± 3 m.y. for the batholith. The lower intercept...
Fluid inclusions in minerals from the geothermal fields of Tuscany, Italy
H. Belkin, B. de Vivo, G. Gianelli, P. Lattanzi
1985, Geothermics (14) 59-72
A reconnaissance study on fluid inclusions from the geothermal fields of Tuscany indicates that the hydrothermal minerals were formed by fluids which were, at least in part, boiling. Four types of aqueous inclusions were recognized: (A) two-phase (liquid + vapor) liquid...
