Evolution, biogeography, and systematics of Puriana: evolution and speciation in Ostracoda, III.
T. M. Cronin
1987, Journal of Paleontology (61)
Three types of geographic isolation—land barriers, deep water barriers, and climatic barriers—resulted in three distinct evolutionary responses in Neogene and Quaternary species of the epineritic ostracode genus Puriana. Through systematic, paleobiogeographic, and morphologic study of several hundred fossil and Recent populations from the eastern Pacific, western Atlantic,...
Ascaulocardium armatum (Morton 1833), new genus (Late Cretaceous): the ultimate variation on the bivalve paradigm
J. Pojeta Jr., N. F. Sohl
1987, Journal of Paleontology (61)
Cretaceous clavagellid pelecypods are a poorly known group, and have previously received little study. Ascaulocardium armatum is conchologically the most complex burrowing pelecypod known. From the study of living clavagellids, it is possible to interpret the various tubes extending outward from the adventitious crypt of A. armatum as devices...
Lungfish burrows in the Upper Triassic Chinle and Dolores Formations, Colorado Plateau
R. F. Dubiel, R.H. Blodgett, T. M. Bown
1987, Journal of Sedimentary Petrology (57) 512-521
Vertical-to-inclined, cylindrical trace fossils that occur in the Upper Triassic Chinle and Dolores Formations on the Colorado Plateau are interpreted to be the casts of lungfish burrows. The casts, which are as much as 11 cm in diameter and as much as 1.6...
Archean inheritance in zircon from late Paleozoic granites from the Avalon zone of southeastern New England: An African connection
R. E. Zartman, Hermes O. Don
1987, Earth and Planetary Science Letters (82) 305-315
In southeastern New England the Narragansett Pier Granite locally intrudes Carboniferous metasedimentary rocks of the Narragansett basin, and yields a monazite UPb Permian emplacement age of 273 ± 2Ma. Zircon from the Narragansett Pier Granite contains a...
Depth-averaging effects on hydraulic head for media with stochastic hydraulic conductivity
R.L. Naff, A. V. Vecchia
1987, Water Resources Research (23) 561-570
Hydraulic conductivity of a porous medium frequently is considered to be a single realization of a three-dimensional spatial stochastic process. The most common observations of flow in porous media are hydraulic-head measurements obtained from wells which are screened over extensive sections of the medium. These measurements represent, approximately, a one-dimensional...
The effects of early diagenesis on the chemical and stable carbon isotopic composition of wood
E.C. Spiker, Patrick G. Hatcher
1987, Geochimica et Cosmochimica Acta (51) 1385-1391
Studies of modern and ancient buried wood show that there is a linear correlation between carbohydrate content and the stable carbon isotope composition as carbohydrates are preferentially degraded during early diagenesis. As the carbohydrate content decreases, the δ13C">δ13C value of the degraded wood decreases 1 to...
Chemical reactions simulated by ground-water-quality models
David B. Grove, Kenneth G. Stollenwerk
1987, Water Resources Bulletin (23) 601-615
Recent literature concerning the modeling of chemical reactions during transport in ground water is examined with emphasis on sorption reactions. The theory of transport and reactions in porous media has been well documented. Numerous equations have been developed from this theory, to provide both continuous and sequential or multistep models,...
Effect of transmitter turn-off time on transient soundings
David V. Fitterman, Walter L. Anderson
1987, Geoexploration (24) 131-146
A general procedure for computing the effect of non-zero turn-off time on the transient electromagnetic response is presented which can be applied to forward and inverse calculation methods for any transmitter-receiver configuration. We consider in detail the case of a large transmitter loop which has a receiver coil located at...
An oxygen isotope model for interpreting carbonate diagenesis in nonmarine rocks (Green River Basin, Wyoming, USA)
W. W. Dickinson
1987, Chemical Geology (65) 103-116
A closed-system model is used for predicting the δ18O of formation waters in the deep portions of the northern Green River basin, Wyoming. δ18Ocalcite is calculated from this modeled water and compared with the δ18O of measured calcites to help interpret diagenesis in the basin.The modification of 18Owater, which may be caused...
Microprocessor-based data-acquisition system for a borehole radar
Jerry A. Bradley, David L. Wright
1987, IEEE Transactions on Geoscience and Remote Sensing (GE-25) 441-447
An efficient microprocessor-based system has been implemented that permits real-time acquisition, stacking, and digital recording of data generated by a borehole radar system. Although the system digitizes, stacks, and records independently of a computer, it is interfaced to a desktop computer for program control over system parameters such as sampling...
The distribution of nitrogen species and adsorption of ammonium in sediments from the tidal Potomac River and estuary
N.S. Simon, M.M. Kennedy
1987, Estuarine, Coastal and Shelf Science (25) 11-26
The distribution of dissolved ammonium, adsorbed ammonium and residual, organic and total nitrogen was measured in Potomac River tidal, transition zone and lower estuary sediments to a depth of 66 cm. For these sediments, exchangeable ammonium, and thereby adsorbed ammonium concentrations, were determined directly using an ammonia electrode in alkaline...
Stochastic simulation of spatially correlated geo-processes
G. Christakos
1987, Mathematical Geology (19) 807-831
In this study, developments in the theory of stochastic simulation are discussed. The unifying element is the notion of Radon projection in Euclidean spaces. This notion provides a natural way of reconstructing the real process from a corresponding process observable on a reduced dimensionality space, where analysis is theoretically easier...
PHYSICAL MODELING OF CONTRACTED FLOW.
Jonathan K. Lee
1987, Conference Paper
Experiments on steady flow over uniform grass roughness through centered single-opening contractions were conducted in the Flood Plain Simulation Facility at the U. S. Geological Survey's Gulf Coast Hydroscience Center near Bay St. Louis, Miss. The experimental series was designed to provide data for calibrating and verifying two-dimensional, vertically averaged...
Petrologic characteristics of the 1982 and pre-1982 eruptive products of El Chichon volcano, Chiapas, Mexico
J. J. McGee, R.I. Tilling, W. A. Duffield
1987, Geofisica Internacional (26) 85-108
Studies on a suite of rocks from this volcano indicate that the juvenile materials of the 1982 and pre-1982 eruptions of the volcano have essentially the same mineralogy and chemistry. Data suggest that chemical composition changed little over the 0.3 m.y. sample period. Modally, plagioclase is the dominant phenocryst, followed...
Alaska interim land cover mapping program
Water Resources Division, U.S. Geological Survey
1987, Data Users Guide 7
In order to meet the requirements of the Alaska National Interest Lands Conservation Act (ANILCA) for comprehensive resource and management plans from all major land management agencies in Alaska, the USGS has begun a program to classify land cover for the entire State using Landsat digital data. Vegetation and land...
Aquatic ecoregions of the conterminous United States
J.M. Omernick
1987, Report
Ecoregions are based on perceived patterns of a combination of causal and integrative factors including land use, land surface form, potential natural vegetation, and soils (Omernik, 1987). This is a copy of the ecoregion coverage of Omernik (1987) with some item names modified. This is NOT the most recent...
The adaptive radiation of photosynthetic modes in the genus Isoetes (Isoetaceae)
Jon E. Keeley
R.M.M. Crawford, editor(s)
1987, Book chapter, Plant Life in Aquatic and Amphibious Habitats.
No abstract available at this time...
Using a spatial and tabular database to generate statistics from terrain and spectral data for soil surveys
E.A. Horvath, E. A. Fosnight, A. A. Klingebiel, D. G. Moore, J.E. Stone
W.U. Reybold, G.W. Petersen, editor(s)
1987, Book chapter, Soil survey techniques, SSSA Special Publication 20
A methodology has been developed to create a spatial database by referencing digital elevation, Landsat multispectral scanner data, and digitized soil premap delineations of a number of adjacent 7.5-min quadrangle areas to a 30-m Universal Transverse Mercator projection. Slope and aspect transformations are calculated from elevation data and grouped according...
Behavioral modification of reproduction in coyotes
D. A. Barnum, J.T. Flinders, J.S. Green
J.S. Green, editor(s)
1987, Protecting livestock from coyotes. A synopsis of research of the Agricultural Research Service. 10-29
No abstract available at this time...
Picture windows of opportunity
S. Matt
1987, Earthquakes & Volcanoes (USGS) (19) 174-177
We hate to say that we need a moderate earthquake every once in a while, but experience shows that it surely helps to sell all kinds of seismic safety programs It took the 933 Long Beach earthquake to get the Field Act passed in California requiring the strengthening of our public schools. It...
Earthquakes, May-June 1987
W. J. Person
1987, Earthquakes & Volcanoes (USGS) (19) 110-112
There were no major earthquakes (7.0-7.9) during this reporting period but earthquake related deaths were reported in Italy, Iran, and the Philippine Islands. In the United States a moderate earthquake occurred in southern Illinois and caused some damage. ...
[Book review] The geochronology and evolution of Africa
Frederic H. Wilson
1987, Precambrian Research (36) 181-182
This book was written 'to provide an up-to-date data bank from which those wishing to construct models concerned with the evolution of Africa .... can draw.' As such, it attempts a survey of 'integrated geology and geochronology' of the African continent throughout the Precambrian and into the Phanerozoic. Political and...
An empirical model for estimating phytoplankton productivity in estuaries
B.E. Cole, J. E. Cloern
1987, Marine Ecology Progress Series (396) 299-305
e have previously shown that primary productivity in San Francisco Bay, USA, is highly correlated with phytoplankton biomass B (chlorophyll a concentration) and an index of light avallability in the photic zone, 2, I, (photic depth times surface irradiance). To test the generality of this relation, we compiled data from...
A compositional multiphase model for groundwater contamination by petroleum products: 1. Theoretical considerations
M. Yavuz Corapcioglu, Arthur L. Baehr
1987, Water Resources Research (23) 191-200
A mathematical model is developed to describe the fate of hydrocarbon constituents of petroleum products introduced to soils as an immiscible liquid from sources such as leaking underground storage tanks and ruptured pipelines. The problem is one of multiphase transport (oil (immiscible), air, and water phases) of a reactive contaminant...
Some effects of climate variability on hydrology in western North America
D. H. Peterson, D.R. Cayan, J. S. Dileo-Stevens, T.G. Ross
1987, Conference Paper, The influence of climate change and climatic variability on the hydrologic regime and water resources (Proceedings of the Vancouver Symposium, August 1987), IAHS Publication no. 168
The strong north-south gradient in precipitation along the West Coast makes this region an interesting laboratory for studying the influence of climate on runoff variability in general and riverine chemistry in particular. Interannual fluctuations in large-scale atmospheric circulation and associated precipitation and runoff can produce major disruptions in the "average"...