Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 1147

ALACARTE user manual

ALACARTE offers a convenient way to compile geologic maps in the computer as spatial databases that can be used to prepare both cartographic images and analytic derivatives. It is a menu-controlled shell, organized in geologic terms, that provides on-screen control of the program ARC/INFO, a commercial geographic information system (GIS). Input can be from imported scans, digitizer tracing, or on-
Authors
Carl M. Wentworth, Todd T. Fitzgibbon

Introduction to special section on the California-Arizona crustal transect: Part II

In May 1988, a multidisciplinary conference was held in Flagstaff, Arizona, to synthesize recent research on the crustal structural and evolution of a transect across the southern Cordillera. This transect extends from the southern Colorado Plateau southwestward across the Arizona Transition Zone, through the Basin and Range province in the Mojave and Sonoran deserts, to the San Andreas fault syst
Authors
G. B. Haxel, R. W. Simpson, Keith A. Howard

The 40Ar/39Ar thermochronology of the eastern Mojave Desert, California, and adjacent western Arizona with implications for the evolution of metamorphic core complexes

Mesozoic thickening and Cenozoic extension resulted in the juxtaposition of upper and middle crustal rocks in the eastern Mojave Desert, southeastern California and western Arizona. The application of 40Ar/39Ar thermochronology to rocks in this region provides information about the timing and nature of thrusting, plutonism, metamorphism, denudation, and detachment faulting. The 40Ar/39Ar ages of 1
Authors
D.A. Foster, T.M. Harrison, C. F. Miller, Keith A. Howard

Geosciences

No abstract available.
Authors
Roger D. Borcherdt, N. C. Donovan, D. Eberhart-Phillips, A. Michael, Paul A. Reasenberg, L. Dietz, W. Ellsworth, Daniel J. Ponti, Ray E. Wells, R. A. Haugerud, M. M. Clark, N. T. Hall

Program to prepare standard figures for grade-tonnage models on a Macintosh

Grade-tonnage models are frequency distributions of deposit tonnage and grades of mineral deposits of a specific type. The program described here allows users to prepare standard figures of grade and tonnage distributions and display the deposit name associated with any of the data points. Titles and scales appropriate for most deposit types are plotted automatically for tonnage, Cu, Ni, Sn, Nb, W
Authors
Donald A. Singer, James D. Bliss

Evolution of the Tertiary La Honda basin, central California

Tertiary strata of the La Honda basin are exposed in the Santa Cruz Mountains along the central California coast south of San Francisco. The basin fill has a composite thickness of more than 14,500 m and consists of sedimentary and volcanic rocks that in places rest on granitic basement rocks of the Salinia terrane. Paleogene strata are mainly turbidite sandstone and hemipelagic mudstone that accu
Authors
Richard G. Stanley