Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

40465 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 1537, results 38401 - 38425

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Influence of San Gabriel submarine canyon on narrow-shelf sediment dynamics, southern California
Herman A. Karl
1980, Marine Geology (34) 61-78
Variations in the concentration of total suspended particulate matter (TSM) collected 1 m above bottom, changes in vertical profiles of light transmission, and substrate textural patterns reveal a corridor for preferential sediment transport on San Pedro continental shelf, California. During the winter, this corridor, designated the preferential transport corridor (PTC),...
Tertiary climates and floristic relationships at high latitudes in the northern hemisphere
J. A. Wolfe
1980, Palaeogeography, Palaeoclimatology, Palaeoecology (30) 313-323
During the Paleocene and Eocene, climates were characterized by a low mean annual range of temperature (a maximum of 10-15??C), a moderate to high mean annual temperature (10-20??C), and abundant precipitation; strong broad-leaved evergreen vegetation extended to almost lat. 60??N during the Paleocene and to well above 61??N during the...
The role of volatiles and lithology in the impact cratering process.
Kieffer S. Werner, C.H. Simonds
1980, Reviews of Geophysics and Space Physics (18) 143-181
A survey of published descriptions of 32 of the largest, least eroded terrestrial impact structures reveals that the amount of melt at craters in crystalline rocks is approximately 2 orders of magnitude greater than at craters in sedimentary rocks. In this paper we present a model for the impact process;...
Circular current loops, magnetic dipoles and spherical harmonic analysis.
L.R. Alldredge
1980, Journal of Geomagnetism & Geoelectricity (32) 357-364
Spherical harmonic analysis (SHA) is the most used method of describing the Earth's magnetic field, even though spherical harmonic coefficients (SHC) almost completely defy interpretation in terms of real sources. Some moderately successful efforts have been made to represent the field in terms of dipoles placed in the core in...
On the extraction of directional sea-wave spectra from synthetic- aperture radar-signal arrays without matched filtering.
R.L. Wildey
1980, Modern Geology (7) 147-159
An economical method of digitally extracting sea-wave spectra from synthetic-aperture radar-signal records, which can be performed routinely in real or near-real time with the reception of telemetry from Seasat satellites, would be of value to a variety of scientific disciplines. This paper explores techniques for such data extraction and concludes...
Distribution of modern benthic foraminifers on the New Jersey Outer Continental Shelf
C. Wylie Poag, H.J. Knebel, R. Todd
1980, Marine Micropaleontology (5) 43-69
We used samples from 21 stations within a 600 km2 area of the New Jersey Outer Continental Shelf to assess the effects of a hydrodynamic environment on the distribution and redistribution of benthic foraminifers. These samples show that, although the predominant genera (Elphidium, Cibicides, and Saccammina) are the same as...
Faulting caused by groundwater level declines, San Joaquin Valley, California
Thomas L. Holzer
1980, Water Resources Research (16) 1065-1070
Approximately 230 mm of aseismic vertical offset of the land surface across the Pond-Poso Creek fault in the San Joaquin Valley, California, probably is related to groundwater withdrawal for crop irrigation. The scarp is approximately 3.4 km long and occurs in an area where the land subsided more than 1.5...
Comment on 'A reinterpretation of the linear heat flow and heat production relationship for the exponential model of the heat production in the crust' by R.N. Singh & J.G. Negi.
A.H. Lachenbruch
1980, Geophysical Journal of the Royal Astronomical Society (63) 791-795
In their recent paper, Singh & Negi, (This journal, 57, 741-744) contend that if thd slope of the empirical linear relation between heat flow and heat production is interpreted as the decay-length of an exponential depth-distribution of sources, a discrepancy rises, whereas if it is interpreted as the depth of...
Tertiary δ18O record and glacio-eustatic sea-level fluctuations
R.K. Matthews, R.Z. Poore
1980, Geology (8) 501-504
Previous interpretation of the Tertiary δ18O record of plaiiktic and benthic foraminifers has emphasized comparison to the modern ocean, assumed an ice-free world prior to middle Miocene time, and thereby calculated surprisingly cool temperatures for the tropical sea surface. We propose an alternative...
Mid- Tertiary climate of southeastern United States, the sporomorph evidence
N. O. Frederiksen
1980, Journal of Paleontology (54) 728-739
Climatic affinities of modern genera represented by late Eocene sporomorphs suggest that the climate of that time in southeastern United States was winter-dry tropical close to the Gulf of Mexico and marginal humid subtropical on the upper Coastal Plain. Lack of change of the sporomorph assemblages suggests that the climate...
Kinetic model for the short-term dissolution of a rhyolitic glass
A. F. White, H.C. Claassen
1980, Chemical Geology (28) 91-109
Aqueous dissolution experiments with the vitric phase of a rhyolitic tuff were performed at 25??C and constant pH in the range 4.5-7.5. Results suggest interchange of aqueous hydrogen ions for cations situated both on the surface and within the glass. At time intervals from 24 to 900 hr., dissolution kinetics...
Travel time variation on backcountry trails
J. W. van Wagtendonk, J.M. Benedict
1980, Journal of Leisure Research (12) 99-106
Numerous interrelated factors influence the travel times of hikers and riders on backcountry trails. This study sought to quantify those factors which were thought to be most important in affecting trail speeds. The travel times of 897 backpacking parties, 634 day hiking parties, and 111 riding parties were obtained from...
The comparison of usage and availability measurements for evaluating resource preference
Douglas H. Johnson
1980, Ecology (61) 65-71
Modern ecological research often involves the comparison of the usage of habitat types or food items to the availability of those resources to the animal. Widely used methods of determining preference from measurements of usage and availability depend critically on the array of components that the researcher, often with a...
Minimum size limits for yellow perch (Perca flavescens) in western Lake Erie
Wilbur L. Hartman, Stephen J. Nepszy, Russell L. Scholl
1980, Technical Report 39
During the 1960's yellow perch (Perca flavescens) of Lake Erie supported a commercial fishery that produced an average annual catch of 23 million pounds, as well as a modest sport fishery. Since 1969, the resource has seriously deteriorated. Commercial landings amounted to only 6 million pounds in 1976, and included...
Lake trout (Salvelinus namaycush) and sea lamprey (Petromyzon marinus) populations in Lake Michigan, 1971-78
LaRue Wells
1980, Canadian Journal of Fisheries and Aquatic Sciences (37) 2047-2051
Lake trout (Salvelinus namaycush) was exterminated in Lake Michigan by the mid-1950s as a result of the combined effects of an intensive fishery and predation by the sea lamprey (Petromyzon marinus). The widespread application of lampricide in tributary streams had greatly reduced the abundance of lampreys by the early 1960s,...
Geochemistry, strontium isotope data, and potassium-argon ages of the andesite-rhyolite association in the Padang area, West Sumatra
G. W. Leo, C. E. Hedge, R. F. Marvin
1980, Journal of Volcanology and Geothermal Research (7) 139-156
Quaternary volcanoes in the Padang area on the west coast of Sumatra have produced two-pyroxene, calc-alkaline andesite and volumetrically subordinate rhyolitic and andesitic ash-flow tuffs. A sequence of andesite (pre-caldera), rhyolitic tuff and andesitic tuff, in decreasing order of age, is related to Maninjau caldera. Andesite compositions range from 55.0...
The Southern California uplift revisited
R. A. Kerr
1980, Earthquake Information Bulletin (USGS) (12) 98-103
The earthquake that struck Livermore, east of San Francisco, on January 24 was the second moderate earthquake to have occurred in the San Francisco Bay area in 5 months. It raised familiar questions. Does this mean that the "Big One" is coming? Is the theater of heightened concern now in...
Earthquakes, January-February, 1980
W. J. Person
1980, Earthquake Information Bulletin (USGS) (12) 200-202
Two major earthquakes (magntidue 7.0-7.9) occurred during this reporting period. The first struck in the North Atlantic Ocean in the Azores Islands on News Year's Day, causing fatalities and damage. The second major quake was on February 24 in the sparsely populated Kuril Islands of the northwest Pacific. A magnitude...
Earthquakes, July-August, 1979
W. J. Person
1980, Earthquake Information Bulletin (USGS) (12) 36-39
There was one major (magnitude 7.0-7.9) earthquake during this reporting period. The quake occurred on August 26 in the Philippine Islands. Strong or damaging earthquakes, which struck many parts of the world, caused casualties and damage; deaths were reported in China and Kashmir, and damaging earthquakes occurred in Costa Rica,...
Toxicity of five forest insecticides to cutthroat trout and two species of aquatic invertebrates
D. F. Woodward, W.L. Mauck
1980, Bulletin of Environmental Contamination and Toxicology (25) 846-854
The Northern Rocky Mountain region has had scattered infestation of the western spruce budworm Christoneura occidentalis since the early 1900's (U.S. DEPARTMENT OF AGRICULTURE (USDA) 1976b). On the basis of aerial surveys in 1975, TUNNOCK et al. (1976), estimated that budworm defoliation occurred on 2,278,804 acres of six National Forests...