Asymmetric measures of association, closed data, and multivariate analysis
M. Hohn, E.B. Nuhfer
1980, Journal of the International Association for Mathematical Geology (12) 235-246
The association between constant-sum variables Xiand Xjexpressed as percentages can be calculated as a product-moment correlation between Xiand Xj/(100 - Xi) and a correlation between Xjand Xi/(100 - Xj). An asymmetric, square matrix may be formed from these coefficients, and multivariate analysis performed by two methods: singular value decomposition and...
Declination and inclination errors in experimentally deposited specularite-bearing sand
S.L. Bressler, D. P. Elston
1980, Earth and Planetary Science Letters (48) 227-232
Naturally disaggregated specularite-bearing sandstone from the Triassic Moenkopi Formation, artificially deposited in controlled magnetic fields of ∼5 × 10−2 mT, acquires a stable remanent magnetization that has systematic errors in inclination and declination. Inclinations about 12° shallower than the applied fields are...
A lead isotope study of mineralization in the Saudi Arabian Shield
J. S. Stacey, B. R. Doe, R. J. Roberts, M.H. Delevaux, J. W. Gramlich
1980, Contributions to Mineralogy and Petrology (74) 175-188
New lead isotope data are presented for some late Precambrian and early Paleozoic vein and massive sulfide deposits in the Arabian Shield. Using the Stacey Kramers (1975) model for lead isotope evolution, isochron model ages range between 720 m.y. and 420 m.y. Most of the massive sulfide deposits in the...
Radar, visual and thermal characteristics of Mars: Rough planar surfaces
G. G. Schaber
1980, Icarus (42) 159-184
High-resolution Viking Orbiter images (10 to 15 m/pixel) contain significant information on Martian surface roughness at 25- to 100-m lateral scales, whereas Earth-based radar observations of Mars are sensitive to roughness at lateral scales of 1 to 30 m, or more....
Computer-composite mapping for geologists
J.N. van Driel
1980, Environmental Geology (3) 151-157
A computer program for overlaying maps has been tested and evaluated as a means for producing geologic derivative maps. Four maps of the Sugar House Quadrangle, Utah, were combined, using the Multi-Scale Data Analysis and Mapping Program, in a single composite map that shows the relative stability of the land...
The 1977 eruption of Kilauea volcano, Hawaii
R. B. Moore, Rosalind Tuthill Helz, D. Dzurisin, G. P. Eaton, R. Y. Koyanagi, P. W. Lipman, J. P. Lockwood, G. S. Puniwai
1980, Journal of Volcanology and Geothermal Research (7) 189-210
Kilauea volcano began to erupt on September 13, 1977, after a 21.5-month period of quiescence. Harmonic tremor in the upper and central east rift zone and rapid deflation of the summit area occurred for 22 hours before the outbreak of surface activity. On the first night, spatter ramparts formed along...
Computational methods for a three-dimensional model of the petroleum-discovery process
J.H. Schuenemeyer, W.J. Bawiec, L.J. Drew
1980, Computers & Geosciences (6) 323-360
A discovery-process model devised by Drew, Schuenemeyer, and Root can be used to predict the amount of petroleum to be discovered in a basin from some future level of exploratory effort: the predictions are based on historical drilling and discovery data. Because marginal costs of discovery and production are a...
Geochemical evolution of brines in the Salar of Uyuni, Bolivia.
S.L. Rettig, B.F. Jones, F. Risacher
1980, Chemical Geology (30) 57-79
Recent analyses of brines from the Salars of Uyuni and Coipasa have been compared with published data for Lakes Titicaca and Poopo to evaluate solute compositional trends in these remnants of two large Pleistocene lakes once connected by overflow from the N to the S of the Bolivian Altiplano. From...
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...
Organic content of Devonian shale in western Appalachian basin
James W. Schmoker
1980, American Association of Petroleum Geologists Bulletin (64) 2156-2165
In the organic-rich facies of the Devonian shale in the western part of the Appalachian basin, the distribution of organic matter provides an indirect measure of both gas in place and the capacity of the shale to supply gas to permeable pathways.The boundary between organic-rich ('black') and organic-poor ('gray') facies...
Depositional environments of some Pleistocene coastal terrace deposits, southwestern Oregon - case history of progradational beach and dune sequence.
R. E. Hunter
1980, Sedimentary Geology (27) 241-262
These deposits comprise a basal gravelly unit and 3 overlying sandy units, each with mud beds, a paleosol, or the modern soil in its uppermost part. The gravelly unit is interpreted as a progradational deposit. The main parts of the sandy units are made up of 1) a crossbedded sand...
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...
Radioactivity method
J. S. Duval
1980, Geophysics (45) 1690-1694
Radioactivity measurements have played an important role in geophysics since about 1935, and they have increased in importance to the present. The most important areas of application have been in petroleum and uranium exploration. Radioactivity measurements have proved useful in geologic mapping, as well as in specialized applications such as...
Resource estimation from historical data: Mercury, a test case
S.M. Cargill, D. H. Root, E. H. Bailey
1980, Journal of the International Association for Mathematical Geology (12) 489-522
A simple technique based on historical records of tonnage and grade of ore produced provides a means for calculating how much of a mineral product will be available in the future at various average grades. Estimates made on this basis are independent of geologic considerations or changing economic and political...
Crustal parameters estimated from P-waves of earthquakes recorded at a small array
J.N. Murdock, J.A. Steppe
1980, Pure and Applied Geophysics PAGEOPH (118) 1179-1190
The P-arrival times of local and regional earthquakes that are outside of a small network of seismometers can be used to interpret crustal parameters beneath the network by employing the time-term technique. Even when the estimate of the refractor velocity is poorly determined, useful estimates of the station time-terms can...
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...
Circum-arctic plate accretion - Isolating part of a pacific plate to form the nucleus of the Arctic Basin
M. Churkin Jr., J.H. Trexler Jr.
1980, Earth and Planetary Science Letters (48) 356-362
A mosaic of large lithospheric plates rims the Arctic Ocean Basin, and foldbelts between these plates contain numerous allochthonous microplates. A new model for continental drift and microplate accretion proposes that prior to the late Mesozoic the Kula plate extended from...
Evolution of the continental margin of southern Spain and the Alboran Sea
William P. Dillon, James M. Robb, H. Gary Greene, Juan Carlos Lucena
1980, Marine Geology (36) 205-226
Seismic reflection profiles and magnetic intensity measurements were collected across the southern continental margin of Spain and the Alboran basin between Spain and Africa. Correlation of the distinct seismic stratigraphy observed in the profiles to stratigraphic information obtained from cores at Deep Sea Drilling Project site 121 allows effective dating...
Flameless atomic-absorption determination of gold in geological materials
A. L. Meier
1980, Journal of Geochemical Exploration (13) 77-85
Gold in geologic material is dissolved using a solution of hydrobromic acid and bromine, extracted with methyl isobutyl ketone, and determined using an atomic-absorption spectrophotometer equipped with a graphite furnace atomizer. A comparison of results obtained by this flameless atomic-absorption method on U.S. Geological Survey reference rocks and geochemical samples...
Map showing water circulation and rates of sedimentation in the Port Isabel 1 degree by 2 degrees quadrangle, Texas
H. L. Berryhill Jr., A. R. Trippet
1980, IMAP 1254-A
No abstract available....
Tectonic stresses in the lithosphere: constraints provided by the experimental deformation of rocks.
S. H. Kirby
1980, Journal of Geophysical Research Solid Earth (85) 6353-6363
The strengths of rocks clearly place an upper limit on the stress that can be sustained by the upper half of the lithosphere. Laboratory data on rock rheology are generally lacking at intermediate temperatures and pressures on the important rock types expected in the lithosphere, so a definitive accounting of...
The size of earthquakes
H. Kanamori
1980, Earthquake Information Bulletin (USGS) (12) 10-15
How we should measure the size of an earthquake has been historically a very important, as well as a very difficult, seismological problem. For example, figure 1 shows the loss of life caused by earthquakes in recent times and clearly demonstrates that 1976 was the worst year for earthquake casualties...
Volcano hazards; lessons learned in the eastern Caribbean
R.S. Fiske
1980, Earthquake Information Bulletin (USGS) (12) 150-154
Earthquake alarm; operating the seismograph station at the University of California, Berkeley.
B. Stump
1980, Earthquake Information Bulletin (USGS) (12) 88-97
An alarm bell rings at the seismographic station and at the office of the campus police. It is 3:00 on a foggy San Francisco morning. Somewhere in the world an earthquake has occurred. The police telephone the duty seismologist at home telling him that the alarm has triggered. He makes...
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...