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Cartographer Mitch Adelson of the U.S. Geological Survey in Menlo Park, Calif., sells topographic maps such as this to visitors from all parts of the country.
U.S. Geological Survey
The U.S. Geological Survey in Menlo Park, Calif., houses rows and rows of maps of fault lines in the U.S.
Slips in the earth cause stress to fault lines, ultimately resulting in an earthquake. Scientists at the U.S. Geological Survey use globes such as the one shown here to study the inner surfaces of the earth and how slips and stresses may occur.