Geologic block diagram
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This diagram shows generalized surficial geology with a cross section showing the geologic interpretation at depth perpendicular (northwest to southeast) to the Hayward Fault (viewed toward the northwest). The cross section cuts through Mission Peak near Fremont (on the right) and crosses the south end of San Francisco Bay near San Jose and Mountain View (on the left). This cross section shows that at its south end the Hayward Fault dips moderately to the northeast, steepening as it merges with the Central Calaveras fault at depth (in the foothills of the Diablo Range east of San Jose in the vicinity between Alum Rock Park and Mount Hamilton). The "creeping" portion of the Hayward Fault system is shown in red. Note that the vertical scale is exaggerated about 2 times the horizontal scale. The cross section on the face of the block diagram is about 10 miles wide (15 km). The image was generated from a USGS 3D geologic map of the Hayward Fault zone. |
