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Classification of mineral deposits into types using mineralogy with a probabilistic neural network

In order to determine whether it is desirable to quantify mineral-deposit models further, a test of the ability of a probabilistic neural network to classify deposits into types based on mineralogy was conducted. Presence or absence of ore and alteration mineralogy in well-typed deposits were used to train the network. To reduce the number of minerals considered, the analyzed data were restricted
Authors
Donald A. Singer, Ryoichi Kouda

An 800,000-year pollen record from Owens Lake, California: Preliminary analyses

A long sequence of fossil palynomorph assemblages from a 323-m-long core taken at Owens Lake has enabled us to evaluate the gross vegetational trends for the Owens Valley region of California over the past ~800,000 years. Shifts in vegetation composition and abundance in the study area during the Pleistocene were indicated in core sediments by marked fluctuations in the pollen frequencies of pines
Authors
Ronald J. Litwin, D.P. Adam, N. O. Frederiksen, W. B. Woolfenden

Mass balance approach to selenium cycling through the San Joaquin Valley, sources to river to bay

Surface and ground waters of the Central Valley of California (e.g., rivers, dams, off-stream storage reservoirs, pumping facilities, irrigation and drinking water supply canals, agricultural drainage canals) are part of a hydrologic system that makes up a complex ecosystem extending from the riparian wetlands of the Sacramento and San Joaquin Rivers through the San Francisco Bay/Delta Estuary to
Authors
Theresa S. Presser, David Z. Piper

Geochemistry of oils from the Junggar basin, northwest China

The Junggar basin of northwestern China is a structural basin containing a thick sequence of Paleozoic-Pleistocene rocks with estimated oil reserves of as much as 5 billion bbl. Analyses of 19 oil samples from nine producing fields and two oil-stained cores in the Junggar basin revealed the presence of at least five genetic oil types. The geochemistry of the oils indicates source organic matter de
Authors
J. L. Clayton, J. Yang, J. D. King, P. G. Lillis, A. Warden

The Blake Nose Cretaceous-Paleogene (Florida Atlantic margin, ODP Leg 171 B): An exemplar record of the Maastrichtian-Danian transition

During ODP Leg 171B, devoted to the analysis of the Blake Plateau margin in front of Florida, 16 holes have been drilled in 5 distinct sites. The sites have documented a sedimentary succession ranging in age from Aptian to Eocene. Emphasis has been put on critical periods, comprising the Paleocene-Eocene transition, the Cretaceous-Tertiary boundary which has been cored in excellent conditions, the
Authors
J. -P. Bellier, S. Marca, Richard D. Norris, D. Kroon, A. Klaus, I. T. Alexander, L. P. Bardot, Charles E. Barker, Charles D. Blome, L. J. Clarke, J. Erbacher, K. L. Faul, M. A. Holmes, Brian T. Huber, Miriam E. Katz, Kenneth G. MacLeod, F. C. Martinez-Ruiz, I. Mita, M. Nakai, James G. Ogg, Dorothy K. Pak, T. K. Pletsch, Jean Self-Trail, N. J. Shackleton, J. Smit, William Ussler, David K. Watkins, J. Widmark, Paul A. Wilson

Preliminary geologic map of the Santa Susana 7.5' quadrangle, southern California: A digital database

This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age
Authors
R.F. Yerkes, R. H. Campbell

Preliminary geologic map of the Moorpark 7.5' quadrangle, Southern California: A digital database

This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age
Authors
R.F. Yerkes, R. H. Campbell

Preliminary geologic map of the Malibu Beach 7.5' quadrangle, Southern California: A digital database

This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by general age
Authors
R.F. Yerkes, R. H. Campbell

Map showing geology, oil and gas fields, and geologic provinces of Europe including Turkey

IntroductionThis digitally compiled map includes geology, geologic provinces, and oil and gas fields of Europe including Turkey. The maps are part of a worldwide series of maps on CD-ROM released by the U.S. Geological Survey's World Energy Project. The goal of the project is to assess the undiscovered, technically recoverable oil and gas resources of the world. For data management purposes the wo
Authors
Mark J. Pawlewicz, Douglas W. Steinshouer, Donald L. Gautier

Maps showing geology, oil and gas fields, and geologic provinces of Iran

This digitally compiled map includes geology, oil and gas field centerpoints, geologic provinces, and major faults of Iran with some of these components extended into geographically adjacent areas. This digital compilation is an interim product of the U.S. Geological Survey's World Energy Project (WEP) and part of a series on CD-ROM. The goal of the WEP is to assess the undiscovered, technically r
Authors
R. M. Pollastro, F.M. Persits, D.W. Steinshouer