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Donald L. Peterson

Publications and source records attributed to Donald L. Peterson.

At least 37 records · Page 2Linked to original sources
USGS1975

Preliminary results of a gravity survey of the Henrys Lake quadrangle, Idaho and Montana

A gravity survey of the Henrys Lake quadrangle shows that a gravity low with about 10 milligals of closure coincides with the Henrys Lake basin. The low is interpreted to reflect a basin fill of 1,100 m or more of Cenozoic sediments and volcanic rock. The data indicate that on the east and probably on the west the basin is bounded by northwest- and north-trending faults, and near its waist by the east-trending Centennial fault. A model constructed across the Henrys Lake basin suggests a northwest-trending fault, located near the southeast corner of Henrys Lake and concealed beneath the basin fill. The sparse gravity data east of the Centennial Mountains are not sufficient to provide any evidence on the extension of the Centennial fault across the Henrys Lake basin.

Idaho, Montana, Wyoming↗
USGS1972

Principal facts for gravity stations for the Central Arizona Project

Observed gravity values, station locations, terrain corrections, and Bouguer gravity data are provided in tabular form for approximately 2460 gravity observations in south-central Arizona. "These data were used in preparation of -- Peterson, Donald L., 1968, Bouguer gravity map of parts of Maricopa, Pima, Pinal, and Yuma Counties, Arizona: U.S. Geol. Survey Geonhvs. Inv. Map GP-615.

Arizona↗
USGS1972

Principal facts for gravity stations in the Bearpaw Mountains and vicinity, Montana

Observed gravity values, station locations, terrain corrections, and Bouguer gravity data are provided in tabular form for approximately 500 gravity observations in north-central Montana. These data were used in preparation of -- Peterson, Donald L. and Rambo, William L., 1967, Bouguer gravity anomaly map of the Bearpaw Mountains and vicinity, Montana: U.S. Geol. Survey open-file report.

Montana↗
USGS1970

Geophysical studies of the Cripple Creek mining district, Colorado

Integrated geophysical, geochemical, and geological interpretations expand the knowledge about the localization of the ore deposits in the Cripple Creek district, Colorado. The principal gold deposits occur in a Tertiary volcanic subsidence basin within Precambrian granite, gneiss, and schist. The basin is filled with volcanic breccia and is intruded by dikes and irregular masses of phonolite, latite-phonolite, syenite, trachydolerite, and basalt. The volcanic complex gives rise to a broad 10 mgal gravity minimum anomaly upon which are superimposed local minima believed to be related to deep mineralized fissure zones. A negative magnetic anomaly over the volcanic subsidence basin probably reflects the degree of alteration of rocks in the subsurface. Two local closed magnetic lows may represent highly altered volcanic centers in the bottom of the basin. The gravity and magnetic anomalies of the basin correlate geographically with positive geochemical anomalies for gold, silver, and tellurium. Just east of the volcanic basin, a prominent negative magnetic anomaly and a corresponding gravity low may represent an altered zone in the granite subsurface.

Colorado↗