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

165846 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 5066, results 126626 - 126650

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
The provenance of rutile.
E. R. Force
1980, Journal of Sedimentary Petrology (50) 485-488
Most coarse detrital rutile is derived from high-grade metamorphic rocks. Contrary to a conventional assumption, independent rutile grains are particularly rare in igneous rocks except alkalic rocks. The use of rutile in the ZTR (zircon-tourmaline-rutile) index of mineralogic maturity is only partially valid,...
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...
Extraction and concentration of phenolic compounds from water and sediment
Marvin C. Goldberg, Eugene R. Weiner
1980, Analytica Chimica Acta (115) 373-378
Continuous liquid-liquid extractors are used to concentrate phenols at the ??g l-1 level from water into dichloromethane; this is followed by Kuderna-Danish evaporative concentration and gas chromatography. The procedure requires 5 h for 18 l of sample water. Overall concentration factors around 1000 are obtained. Overall concentration efficiencies vary from...
Nd-isotopes in selected mantle-derived rocks and minerals and their implications for mantle evolution
A. R. Basu, M. Tatsumoto
1980, Contributions to Mineralogy and Petrology (75) 43-54
The Sm-Nd systematics in a variety of mantle-derived samples including kimberlites, alnoite, carbonatite, pyroxene and amphibole inclusions in alkali basalts and xenolithic eclogites, granulites and a pyroxene megacryst in kimberlites are reported. The additional data on kimberlites strengthen our earlier conclusion that kimberlites are derived from a relatively undifferentiated chondritic...
Petrology of Hualalai volcano, Hawaii: Implication for mantle composition
D.A. Clague, E.D. Jackson, T. L. Wright
1980, Bulletin Volcanologique (43) 641-656
Hualalai is one of five volcanoes whose eruptions built the island of Hawaii. The historic 1800-1801 flows and the analyzed prehistoric flows exposed at the surface are alkalic basalts except for a trachyte cone and flow at Puu Waawaa and a trachyte maar deposit near Waha Pele. The 1800-1801 eruption...
Evaluation of organic matter, subsurface temperature and pressure with regard to gas generation in low-permeability Upper Cretaceous and Lower Tertiary sandstones in Pacific Creek area, Sublette and Sweetwater Counties, Wyoming.
B. E. Law, C. W. Spencer, N. H. Bostick
1980, Mountain Geologist (17) 23-35
The onset of overpressuring occurs at c.3,500 m, near the base of the U. Cretaceous Lance Formation. The development of overpressuring may involve several processes; however, interpretation of the available information indicates that active generation of large amounts of wet gas is one of the more important processes. The present...
Compositional controls on spinel clouding and garnet formation in plagioclase of olivine metagabbros, Adirondack Mountains, New York
J. M. McLelland, P.R. Whitney
1980, Contributions to Mineralogy and Petrology (73) 243-251
Olivine metagabbros from the Adirondacks usually contain both clear and spinel-clouded plagioclase, as well as garnet. The latter occurs primarily as the outer rim of coronas surrounding olivine and pyroxene, and less commonly as lamellae or isolated grains within plagioclase. The formation of garnet and metamorphic spinel is dependent upon...
Upper Wisconsinan till recovered on the continental shelf southeast of New England
Michael H. Bothner, Elliott C. Spiker
1980, Science (210) 423-425
Basal till was identified in two sediment cores collected about 69 kilometers southeast of Nantucket Island on the east and west sides of Great South Channel. These are the first samples of till collected on the outer continental shelf off the northeastern United States. The carbon-14 age of the total...
Morphology of Lonar Crater, India: Comparisons and implications
R.F. Fudali, D.J. Milton, K. Fredriksson, A. Dube
1980, The Moon and the Planets (23) 493-515
Lonar Crater is a young meteorite impact crater emplaced in Deccan basalt. Data from 5 drillholes, a gravity network, and field mapping are used to reconstruct its original dimensions, delineate the nature of the pre-impact target rocks, and interpret the emplacement mode of the ejecta. Our estimates of the pre-erosion...
Sedimentary masses and concepts about tectonic processes at underthrust ocean margins
D.W. Scholl, Roland E. von Huene, T.L. Vallier, D. G. Howell
1980, Geology (8) 564-568
Tectonic processes associated with subduction of oceanic crust, but unrelated to the collision of thick crustal masses or microplates, are presumed by many geologists to significantly affect the formation and deformation of large sedimentary bodies at underthrust ocean margins. More geologists are familiar with the concept of subduction accretion, which describes...
Applications of statistics to thematic mapping.
G.H. Rosenfield, M.L. Melley
1980, Photogrammetric Engineering and Remote Sensing (46) 1287-1294
Two statistical problems occurring in the effort to analyze thematic maps and mapping are determining the accuracy of thematic content and comparing factors studied in thematic mapping. Statistical procedures applicable to thematic mapping involve sampling, determining accuracy, and comparing factors. A sampling procedure using an unaligned pattern within a square...
The nature of fracturing and stress distribution in quartzite around the 1128-M (3700-FT) level of the crescent mine, Coeur d'Alene mining district, Idaho
C.H. Miller, E.H. Skinner
1980, Engineering Geology (16) 321-338
Silver and copper are the principal ores mined from the quartzite at the Crescent mine. Both the main ore-bearing veins and foliation in the quartzite are parallel to the nearly vertical formational contacts. Anisotropy of the quartzite is indicated by both dynamic and static tests. Disking and breakage of core...
Atlantic Flyway review: Region V: Laurel, Prince Georges County, MD (390-0765)
Chandler S. Robbins
1980, North American Bird Bander (5) 34-34
Despite a 22% increase in net-hours, the number of new birds banded dropped 26% from 1977. The decrease was noted in each month and was spread among all of the commonest species, including summer residents, winter residents, permanent residents, and transients. The greatest declines were in Scarlet Tanager (84%), Blue...
Changes in mortality of lake trout (Salvelinus namaycush) in Michigan waters of Lake Superior in relation to sea lamprey (Petromyzon marinus) predation, 1968-78
Richard L. Pycha
1980, Canadian Journal of Fisheries and Aquatic Sciences (37) 2063-2073
Total mortality rates of lake trout (Salvelinus namaycush) of age VII and older from eastern Lake Superior were estimated from catch curves of age distributions each year in 1968–78. The instantaneous rate of total mortality Z varied from 0.62 to 2.31 in close synchrony with sea lamprey (Petromyzon marinus) wounding rates on lake...
Water quality of Tampa Bay, Florida, June 1972 - May 1976
Carole L. Goetz, Carl R. Goodwin
1980, Water-Resources Investigations Report 80-12
A comprehensive assessment of the water quality of Tampa Bay, Florida, was initiated in 1970 to provide background information to evaluate the effects of widening and deepening the ship channel to the port of Tampa. This report provides results of water-quality sampling in the bay from 1972 to 1976, prior...