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Science Tour - 3D/4D mapping of the San Andreas Fault Zone

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Surficial geologic mapping is fundamental science: Geologic maps are interpretations based on data and guided intuition. Geologists use information derived from aerial photography combined with data collected from often arduous field checking. Geologist also rely on information provided from geophysical data (gravity, magnetism, electrical resistivity, background radiation mapping, etc.), well data, and rock and paleontological repository collections to create geologic maps. Perhaps most important is the guided instruction from other experienced scientists through professional education and collaboration, and the research and mapping that has been conducted and published previously.

The geologic map below illustrates how geologic information is shown in 2 dimensions (an area geologic map). The map also include a legend of mapable units and a line showing the location of a cross-sectional profile that adds a third dimension (3D) to the geologic interpretation.
Geologic map of the Wilbur Hot Springs area, northern California
Graphic provided by Robert McLaughlin; revised from:

McLaughlin, R. J., Ohlin, H. N., and Thormahlen, D. J., , 1990, Geologic map and structure sections of the Little Indian Valley - Wilbur Springs geothermal area, northern Coast Ranges, California: U.S. Geological Survey Miscellaneous Information Series Map, I-1706, scale: 1:24,000.

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