Rare-earth element geochemistry of the island-arc volcanic rocks of Rabaul and Talasea, New Britain
Joseph G. Arth
1981, Geological Society of America Bulletin (92) 858-863
The island-arc volcanic rocks of Rabaul and Talasea, New Britain, range in composition from basalt through rhyolite. Rare-earth elements have been determined by mass-spectrometric isotope dilution in 16 samples. Chondrite-normalized rare-earth element patterns are distinct for each volcanic center, but all are relatively flat (Ce/YbE.F. = 1.1 to 3.0). Within...
Uranium-series and soil-geomorphic dating of the Calico archaeological site, California
James L. Bischoff, Roy J. Shlemon, T. L. Ku, R.D. Simpson, Robert J. Rosenbauer, Budinger
1981, Geology (9) 576-582
Lithic specimens identified as artifacts have been recovered from near the base of the Yermo fan deposits at Calico, California. The soil on the fan surface is a strongly developed relict paleosol. Comparison of this soil with dated paleosols elsewhere in the southwestern United States suggests that the surface is...
Temporal and spatial variations in suspended matter in continental shelf and slope waters off the north-eastern United States
Michael H. Bothner, Carol M. Parmenter, John D. Milliman
1981, Estuarine, Coastal and Shelf Science (13) 213-234
Seston in waters of Georges Bank originates primarily from biological production and from resuspension of bottom sediments. The concentrations of suspended matter observed on the central shoals are more influenced by storms than by seasonal changes. Winter storms produce highest concentrations of non-combustible material throughout the water column, and summer...
Proterozoic zircon from augen gneiss, Yukon-Tanana Upland, east-central Alaska
John N. Aleinikoff, Cynthia Dusel-Bacon, Helen L. Foster, Kiyoto Futa
1981, Geology (9) 469-473
U-Th-Pb analyses of zircons from an ortho-augen gneiss body in the Yukon-Tanana Upland of east-central Alaska yield strong evidence for the presence of early Proterozoic material in this area. U-Pb data define a chord that intersects concordia at about 2,300 and 345 m.y. We consider two interpretations: (1) the protolith...
Geologic transect of the northern Diablo Range, California
M. Clark Blake Jr.
1981, Conference Paper, Upper Mesozoic Franciscan Rocks and Great Valley Sequence, Central Coast Ranges, California: Field Trip Guide V
No abstract available....
Deep volcanic tremor and magma ascent mechanism under Kilauea, Hawaii
Keiiti Aki, Robert Y Koyanagi
1981, Journal of Geophysical Research B: Solid Earth (86) 7095-7109
Deep harmonic tremor originating at depths around 40 km under Kilauea was studied using records accumulated since 1962 at the Hawaii Volcano Observatory of the U.S. Geological Survey. The deep source of the tremor was determined by onset times and confirmed by the relative amplitude across the island-wide network of...
United States gold resource profile
S.M. Cargill
1981, Economic Geology (76) 937-943
No abstract available...
Estimation of depth to magnetic source using maximum entropy power spectra, with application to the Peru-Chile Trench
Richard J. Blakely
1981, Memoir of the Geological Society of America (154) 667-682
Estimations of the depth to magnetic sources using the power spectrum of magnetic anomalies generally require long magnetic profiles. The method developed here uses the maximum entropy power spectrum (MEPS) to calculate depth to source on short windows of magnetic data; resolution is thereby improved. The method operates by dividing...
A diver operated reverse corer to collect samples of unconsolidated coarse sand
Roberto J. Anima
1981, Journal of Sedimentary Petrology (51) 653-654
No abstract available...
Decontaminating and recycling zinc bromide solution used in sink-float separation of kerogen
Charles E. Barker
1981, Journal of Sedimentary Research (51) 666-667
No abstract available...
Holocene pollen and sediment record from the tangle lakes area, central Alaska
Thomas A. Ager, John D. Sims
1981, Palynology (5) 85-98
Pollen and sediments have been analyzed from a 5.5 meter‐length core of lacustrine sediments from Tangle Lakes, in the Gulkana Upland south of the Alaska Range (63 ° 01 ‘ 46”; N. latitude, 146° 03 ‘ 48 “ W. longitude). Radiocarbon ages indicate that the core spans the last 4700...
Chrysophyte cysts as potential environmental indicators
David P. Adam, Albert D. Mahood
1981, Geological Society of America Bulletin (92) 839-844
Many Chrysophyte algae produce morphologically distinctive, siliceous, microscopic cysts during a resting stage of their life cycles; these cysts are often preserved in sediments. Scanning electron microscopy and Nomarski optics permit much more detailed observation of these cysts than was heretofore possible. We have used an ecologic and biogeographic approach...
Radiometric and paleomagnetic evidence for the Emperor reversed polarity event at 0.46 ± 0.05 M.Y. in basalt lava flows from the eastern Snake River Plain, Idaho
Duane E. Champion, G. Brent Dalrymple, Mel A. Kuntz
1981, Geophysical Research Letters (8) 1055-1058
K-Ar and paleomagnetic data from cores through a sequence of basalt flows in the eastern Snake River Plain provide evidence for a brief (0.005 to 0.01 m.y.) reversal of the geomagnetic field 0.46 ± 0.05 m.y. ago. This reversed polarity event has also been found in sea-floor magnetic anomalies and...
Linear island and seamount chains, aseismic ridges and intraplate volcanism: Results from DSDP
David A. Clague
1981, SEPM Special Publication (32) 7-22
The Deep Sea Drilling Project drilled a substantial number of sites that bear on the origin of linear island and seamount chains, aseismic ridges and other more regional expressions of intraplate volcanism. Drilling in the Emperor Seamounts during Leg 55 was particularly successful. Results from this leg include: 1)...
Conceptual models governing leaching behavior and their long-term predictive capability
Hans C. Claassen
1981, Nuclear and Chemical Waste Management (2) 307-313
Six models that may be used to describe the interaction of radioactive waste solids with aqueous solutions are as follows:Simple linear mass transfer;Simple parabolic mass transfer;Parabolic mass transfer with the formation of a diffusion-limiting surface layer at an arbitrary time;Initial parabolic mass transfer followed by linear mass transfer at an...
Rectangular harmonic analysis applied to the geomagnetic field
L.R. Alldredge
1981, Journal of Geophysical Research B: Solid Earth (86) 3021-3026
Spherical harmonic analysis of the earth's magnetic field is limited in the resolution that can be obtained. This limitation is caused by inadequacies of computers and of available data sets. The fundamental wavelength in spherical harmonic analysis is the circumference of the earth. To resolve wavelengths as short as 100...
Potential source for crushed granite aggregate in Heard County, Georgia
R. L. Atkins, Michael W. Higgins, Robert P. Dickerson
1981, Report
The production of crushed stone suitable for highway and general construction is a major industry in Georgia. The state ranks eighth in the nation in overall crushed stone production, and first in crushed granite production. Crushed stone production in Georgia in 1979 was 40,902,000 short tons worth $154,021,000 (D.H. White,...
Economic geology of Tioga and Bradford Counties
P.B. Luce, W.E. Edmunds
1981, Conference Paper, Guidebook for the 46th Annual Field Conference of Pennsylvania Geologists
No abstract available...
On the use of nonlinear soil models
Albert T.F. Chen
1981, Conference Paper, Proceedings: First International Conference on Recent Advances in Geochemical Earthquake Engineering and Soil Dynamics
The basic definitions of, and the differences between, currently available soil models are reviewed. These models are applied to site response analyses where two depths and two levels of base input motion are considered. Computational results are presented and compared with regard to the effects of using different soil models...
Sedimentology of Great Sand Dunes, Colorado
Sarah Andrews
1981, SEPM Special Publication 31
Eolian and adjacent deposits of Great Sand Dunes Colorado form a small but sedimentologically complex deposit Eolian sediments can be subdivided into three provinces trending downwind northeast I low as much as 10 m high alkali cemented dunes forming discontinuous rings around broad flat bottomed ephemeral lakes II undulating vegetated...
Subdivision and regional stratigraphy of the pre-Punta Gorda rocks (lowermost cretaceous-jurassic?) in South Florida
A.V. Applegate, George O. Winston, James George Palacas
1981, Gulf Coast Association of Geological Societies Transactions (31) 447-453
In recent years several wells have been drilled in the South Florida Basin through carbonate and evaporite sequences to depths as much as 5,300 ft below the Punta Gorda Anhydrite. The deepest well penetrated igneous basement rocks to a total depth of 18, 670 ft. Correlation of anhydrite beds below...
Road log
T.M. Berg, G.H. Crowl, W.E. Edmunds, P.B. Luce, W. D. Sevon, P. Wilshusen, Donald L. Woodrow, H. A. Pohn, editor(s)
1981, Conference Paper, Guidebook for the 46th Annual Field Conference of Pennsylvania Geologists
No abstract available...
Seismic zonation in the San Francisco Bay region
E. E. Brabb
1981, Conference Paper, Proceedings: Social and economic impact of earthquakes on utility lifelines: Seismic considerations in lifelines planning, siting and design: Construction Division specialty conference
No abstract available....
An iridium abundance anomaly at the palynological Cretaceous-Tertiary boundary in northern New Mexico
C. J. Orth, J. S. Gilmore, J.D. Knight, C. L. Pillmore, R.H. Tschudy, J.E. Fassett
1981, Science (214) 1341-1343
An iridium abundance anomaly, with concentrations up to 5000 parts per trillion over a background level of 4 to 20 parts per trillion, has been located in sedimentary rocks laid down under freshwater swamp conditions in the Raton Basin of northeastern New Mexico. The anomaly occurs at the base of...
Geodetic measurement of crustal deformation on the San Andreas, Hayward, and Calaveras faults near San Francisco, California
W.H. Prescott, Michael Lisowski, James C. Savage
1981, Journal of Geophysical Research B: Solid Earth (86) 10853-10869
Analysis of a geodetic network of 115 lines crossing the San Andreas, Hayward, and Calaveras faults in the vicinity of San Francisco Bay and measured repeatedly between 1970 and 1980 has revealed details about the accommodation of relative plate motion in this area. The most striking result is that the...
