Radiometric age map of northern Alaska
Frederic H. Wilson, D. L. Turner
1975, Alaska Division of Geological & Geophysical Surveys Open File Report DGGS AOF 86
This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each...
Radiometric age map of Aleutian Islands
Frederic H. Wilson, D. L. Turner
1975, Alaska Division of Geological & Geophysical Surveys Open File Report DGGS AOF 83
This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each...
Radiometric age map of southcentral Alaska
Frederic H. Wilson, D. L. Turner
1975, Alaska Division of Geological & Geophysical Surveys Open File Report DGGS AOF 85
This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each...
Effect of geologic structure and metamorphic fluids on seismic behavior of the San Andreas fault system in central and northern California
William P. Irwin, Ivan Barnes
1975, Geology (3) 713-716
No abstract available....
Radiometric age map of southeast Alaska
Frederic H. Wilson, D. L. Turner
1975, Report
This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each...
Chemical compositions of Kilauea east-rift lava, 1968–1971
Thomas L. Wright, Don Swanson, Wendell A. Duffield
1975, Journal of Petrology (16) 110-133
The major element chemical compositions of lava from four eruptions on the east rift zone of Kilauea between August 1968 and October 1971 reflect three petrologic processes:Production of chemically distinct batches of magma in the mantle.Separation of olivine, augite, and plagioclase from liquid during flow in the rift-zone conduits.Mixing...
Chino Valley formation (Cambrian?) in northwestern Arizona
Richard Hereford
1975, GSA Bulletin (86) 677-682
A thin persistent unit (maximum thickness 13 m) of probable Cambrian age in the Chino Valley region of northwestern Arizona consists of three laterally equivalent, mutually exclusive lithofacies. These are, from west to east, lithic sandstone, pebble to boulder conglomerate, and dolomite. The unit, named the Chino Valley Formation, is...
Discussion of uranium availability and the breeder decision
W.I. Finch, R. P. Fischer, A.P. Butler Jr., C.D. Masters, F. W. Stead
1975, Energy Systems and Policy (1) 259-269
No abstract available. ...
Crustal movement investigations
James C. Savage
1975, Reviews of Geophysics (13) 263-265
Studies of horizontal crustal movement using conventional geodetic methods have been considerably expanded in the quadrennium 1971–1974. The basic fault monitor Geodimeter network now covers most of the major faults in California as well as the zone of faulting that extends into Nevada. Isolated Geodimeter networks in seismic areas of...
Land classification of south-central Iowa from computer enhanced images
James R. Lucas, James V. Taranik, Frederic C. Billingsley
1975, Report 3
The author has identified the following significant results. Two enhanced false color negatives from multispectral scanner scenes, dated 15 April 1974 and 29 August 1972, were printed at a scale of 1:125,000 to form the basis for land use interpretations in the Wapello County, Iowa test site. The use of...
Generation of potassium-poor magmas in the northern Sierra Nevada and the Svecofennian of Finland
Anna Hietanen
1975, Journal of Research of the U.S. Geological Survey (3) 631-645
Comparison of the evolution of magmas in the Precambrian of southwestern Finland with that in the Paleozoic and Mesozoic of the northern Sierra Nevada brings out features that may clarify the origin of potassium-poor silicic magmas. In the northern Sierra Nevada, Paleozoic sodarhyolitic effusive rocks and associated trondhjemite represent silicic...
Ion-selective electrode determination of iodine in rocks and soils
W. H. Ficklin
1975, Journal of Research of the U.S. Geological Survey (3) 753-755
Use of an iodide-ion-selective electrode permits rapid and fairly accurate determination of iodine (as iodide) in rocks and soils. When a 1-g sample is used, concentrations as small as 0.5 ppm can be determined with a precision of about 25-percent relative standard deviation. When bromine concentration is greater than 5...
Absolute age of disseminated uraninite in Wheeler Basin, Grand County, Colorado
K.R. Ludwig, E. J. Young
1975, Journal of Research of the U.S. Geological Survey (3) 747-751
Uranium and lead isotopic analyses of monazlte and uraninite from the disseminated uraninite occurrence at Wheeler Basin, Grand County, Colo., indicate that these minerals formed 1,446±20 m.y. ago. This time correlates well with intrusion of the Silver Plume Granite. The uraninite and monazite were also affected by a later disturbance...
A late Holocene pollen diagram from near Lake Tahoe, El Dorado County, California
Alojz Sercelj, David P. Adam
1975, Journal of Research of the U.S. Geological Survey (3) 737-745
A 2,500-yr pollen record from an alpine meadow in the central Sierra Nevada shows a general agreement with other more detailed pollen records from the late Holocene of California. Tree roots from the site suggest dry conditions at about 1150 and 1350 radiocarbon yr B.P....
Modern pollen surface samples: An analysis of subsamples
David P. Adam, Peter J. Mehringer
1975, Journal of Research of the U.S. Geological Survey (3) 733-736
Multiple subsamples of pollen samples obtained from the modern soil surface at two sites in southern Arizona were individually collected and analyzed to evaluate the practice of mixing subsamples when collecting modern surface samples. Results suggest that at least five subsamples must be mixed in order to avoid collecting a...
A late Holocene pollen record from Pearson's Pond, Weeks Creek landslide, San Francisco Peninsula, California
1975, Journal of Research of the U.S. Geological Survey (3) 721-731
A 210-cm core from Pearson's Pond yielded a pollen record for the past 3 millenia. Prior to A.D. 1000 the pond biota was particularly sensitive to climatic fluctuations. Two wet intervals occur in the pollen record, between 350 B.C. and A.I). 0 and between A.D. 650 and 900. The pollen...
Stratigraphy, conodont dating, and paleotectonic interpretation of the type Milligen Formation (Devonian), Wood River area, Idaho
Charles Sandberg, Wayne E. Hall, John N. Batchelder, Claus Axelsen
1975, Journal of Research of the U.S. Geological Survey (3) 707-720
The Milligen Formation at and near its type locality in the Wood River area is considerably older than and unrelated to rocks of Early Mississippian age called Milligen Formation in the Lost River Range and other ranges of east-central Idaho. Conodont faunas were found in limestones of a thin upper...
Silurian and Devonian miogeosynclinal and transitional rocks of the Fish Creek Reservoir window, central Idaho
Betty A. Skipp, Charles Sandberg
1975, Journal of Research of the U.S. Geological Survey (3) 691-706
Documentation of Devonian continental-shelf shallow-water carbonate rocks in the core of the Fish Creek Reservoir window shifts the known westernmost limit of the Devonian miogeosyncline 50 km (30 mi) southwest across the structural grain from the well-known miogeosynclinal sequence in the Lost River Range. The miogeosynclinal carbonate sequence in the...
Structure and Paleozoic stratigraphy of a complex of thrust plates in the Fish Creek Reservoir area, south-central Idaho
Betty A. Skipp, Wayne E. Hall
1975, Journal of Research of the U.S. Geological Survey (3) 671-689
Permian, Pennsylvanian, Mississippian, Devonian, and Silurian marine rocks of diverse facies are brought together in a complex of six thrust sheets in the Fish Creek Reservoir area on the north edge of the Snake River Plain, Idaho. The lowest structural element, the parautochthon, is made of more than 450 m...
Description of the geoelectric section, Rattlesnake Hills unit 1 well, Washington
Dallas B. Jackson
1975, Journal of Research of the U.S. Geological Survey (3) 665-669
A complex 64-in. normal log from the 3,249-m-deep Rattlesnake Hills well was digitized and reduced to a form resembling a simple resistance log. The simplified form of the log made it possible to recognize three major geoelectric intervals in the well that were not apparent on the original log. The...
Phosphate fertilizer materials in Colombia; imports, uses, and domestic supplies
James B. Cathcart
1975, Journal of Research of the U.S. Geological Survey (3) 659-663
The distribution of potentially economic phosphate deposits and the locations of major users of phosphate products in Colombia are some of the economic factors that indicate the capability of the deposits to supply domestic demands. Much research is required to determine the types of processing plants needed and to outline...
Progressive metamorphism of schists recovered from a deep drill hole near Fairbanks, Alaska
Robert B. Forbes, Florence R. Weber
1975, Journal of Research of the U.S. Geological Survey (3) 647-657
In 1965, a deep test hole drilled near Eielson Air Force Base, Fairbanks district, Alaska, penetrated 9,774 ft (2,979.1 m) into schists of the metamorphic complex of the Yukon-Tanana Upland. Cores recovered from the test hole show that the section is dominated by calc-magnesian rocks with subordinate pelitic schists. Pelitic...
Evaluation of stochastic models describing movement of sediment particles on riverbeds
Petar Todorovic, Carl F. Nordin Jr.
1975, Journal of Research of the U.S. Geological Survey (3) 513-517
Various stochastic models have been proposed to describe the movement of sediment particles on the riverbed. Here it is attempted to summarize in an integrated form and to generalize the most important theoretical results in this field. The approach adopted in this paper is based on the fact that most...
Revised value for the O18 fractionation between CO2 and H2O at 25°C
James R. O’Neil, Lanford H. Adami, Samuel Epstein
1975, Journal of Research of the U.S. Geological Survey (3) 623-624
A new value of 1.0412 for the fractionation factor a between CO2 and H2O at 25°C is recommended on the basis of new data and a reevaluation of earlier published data....
Tectonics of the western Valley and Ridge foldbelt, Pendleton County, West Virginia - a summary report
William J. Perry Jr.
1975, Journal of Research of the U.S. Geological Survey (3) 583-588
A belt of high anticlines, the Nittany anticlinorium, occupies the western Valley and Ridge foldbelt in the central Appalachians. It extends southwestward from the Nittany arch of central Pennsylvania into the Virginias. An investigation of the tectonics of this anticlinorium in Pendleton County, W. Va., rules out active basement involvement...
