Jachens, Robert C.


Gravity survey and interpretation of Fort Irwin and vicinity, Mojave Desert, California

Provides a view of alluvial basins, shapes, areal extents, and approximate thicknesses of alluvial fill. Gravity field is separated into density variations in the basement complex and distribution of Cenozoic fill with its 3-D thickness representation.

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Preliminary aeromagnetic anomaly map of California

Map showing magnetic anomaly of California composed by merging and editing data from 123 distinct surveys conducted previously.

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Principal facts for gravity stations in the vicinity of San Bernardino, southern California

Gravity measurements collected to help define the characteristics of the Rialto-Colton fault, with rock properties such as lithology, magnetic susceptibility and density.

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Gravity map and data of the eastern half of the Big Bear Lake, 100,000 scale quadrangle, California, and analysis of the depths of several basins

Data on the southern portion of the Marine Corps Air Ground Combat Center (MCAGCC) Twentynine Palms and the Yucca Valley-Joshua Tree-Twentynine Palms area and presents the map and basin analyses.

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Modeling of the Climax Stock and related plutons based on the inversion of magnetic data, southwest Nevada

Mathematical modeling, coupled with new observations of magnetic susceptibility, yield better estimates of the underground configuration of granite plutons.

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Preliminary gravity and magnetic data of the Lake Pillsbury northern Coast Ranges, California

Report with excel tables showing principal facts (gravity observation data) and ground magnetic data.

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Aeromagnetic survey map of the central California coast ranges

Intended to promote further understanding of the geology and structure in the central California Coast Ranges, includes downloadable gridded point database.

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Aeromagnetic and aeromagnetic-based geologic maps of the Coastal Belt, Franciscan Complex, northern California

New aeromagnetic point observation data with grids as well

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Aeromagnetic data, processing, and maps of Fort Irwin and vicinity, California

Aeromagnetic data help provide the underpinnings of a hydrogeologic framework for Fort Irwin by locating inferred structural features or grain that influence groundwater flow. Magnetization boundaries defined by horizontal-gradient analyses coincide lo

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Preliminary potential-field constraints on the geometry of the San Fernando basin, southern California

Results of mathematical modeling of gravity and magnetic anomaly data to infer the geologic structure of the area

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Isostatic gravity map of the Monterey 30x60 minute quadrangle and adjacent areas, California

Gravity measurements to support regional mapping and hydrologic studies

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Principal facts for gravity stations in the vicinity of Coyote Spring valley, Nevada, with initial gravity modeling results

Gravity study to help define the shapes of young basins filled with Cenozoic rocks and alluvium, and to identify any possible faults within these basins that might influence the movement of groundwater.

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Isostatic gravity map with geology of the Santa Ana 30'x60' quadrangle, southern California

Contour map of isostatic gravity anomaly with bedrock geology, and principal facts for the gravity stations as a separate data file.

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Preliminary isostatic gravity map of the Sonoma Volcanic field and vicinity, Sonoma and Napa counties, California

Gravity station data from three separate surveys

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