Photomosaics and logs of trenches on the San Andreas Fault at Mill Canyon near Watsonville, California

Thomas E. Fumal; Timothy E. Dawson; Rebecca Flowers; John C. Hamilton; Gordon F. Heingartner; James Kessler; Laura Samrad

doi:10.3133/ofr03469

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Photomosaics and logs of trenches on the San Andreas Fault at Mill Canyon near Watsonville, California

Thomas E. Fumal·Timothy E. Dawson·Rebecca Flowers·John C. Hamilton·Gordon F. Heingartner·James Kessler·Laura Samrad

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Abstract

We present photomosaics and logs of the walls of trenches excavated for a paleoseismic study at Mill Canyon, one of two sites along the San Andreas fault in the Santa Cruz Mtns. on the Kelley-Thompson Ranch. This site was a part of Rancho Salsipuedes beginning in 1834. It was purchased by the present owner’s family in 1851. Remnants of a cabin/mill operations still exist up the canyon dating from 1908 when the area was logged. At this location, faulting has moved a shutter ridge across the mouth of Mill Canyon ponding Holocene sediment. Recent faulting is confined to a narrow zone near the break in slope.

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Source-reported bounding extent: 36.858232° to 37.08012° latitude; -122.022445° to -121.566315° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Thomas E. Fumal, Timothy E. Dawson, Rebecca Flowers, John C. Hamilton, Gordon F. Heingartner, James Kessler, Laura Samrad. 2004. Photomosaics and logs of trenches on the San Andreas Fault at Mill Canyon near Watsonville, California. https://doi.org/10.3133/ofr03469

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