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The name of the map which is displayed above is highlighted in orange, below. To view another of the coastal geology maps, choose from the list below.
1: Thornton Beach 2: Mussel Rock 3: Sharp Park 4: Mori Point 5: Point San Pedro 6: Devils Slide 7: Point Montara 8: Seal Cove 9: Pillar Point 10: Miramar 11: Half Moon Bay 12: Miramontes Point 13: Eel Rock 14: Seal Rock 15: Martins Beach 16: Tunitas Creek 17: San Gregorio Beach 18: Pomponio Beach 19: Pescadero Beach 20: Pebble Beach 21: Bolsa Point 22: Pigeon Point 23: Franklin Point North 24: Franklin Point South 25: Point Año Nuevo 26: Año Nuevo Creek
1982-83 El Niño Coastal Erosion: San Mateo County, California
Kenneth R. Lajoie and Scott A. Mathieson
Coastal Geology Maps
The erosion information presented on the coastal erosion maps is placed in a geologic context on twenty-six coastal geology maps using the same bases as the coastal erosion maps. The geology maps generalize coastal morphology and geology by means of schematic cross sections. Natural coastal processes such as cliff erosion, slope failure, wave erosion, landslides, block falls, debris slides, and cave collapse are illustrated diagrammatically on the cross sections. Ultimately, wave erosion is the primary or initiating erosive process along the San Mateo County coast. Waves erode the base of the sea cliffs or coastal bluffs, thus oversteepening and destabilizing the slopes above. Landslides, debris slides, and block falls are secondary erosive agents that move loosened rock material down the slopes to the beaches below, where the material is eventually eroded away by wave activity. Along most of the San Mateo County coast groundwater that seeps from the cliff face softens and loosens even otherwise resistent bedrock material, thus contributing to the erosional process.
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