USGS Open-File Report 03-469: Photomosaics and Logs of Trenches on the San Andreas Fault at Mill Canyon Near Watsonville, California

Photomosaics and Logs of Trenches on the San Andreas Fault at Mill Canyon Near Watsonville, California

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

Introductions

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 begining 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.

First posted December 5, 2003

Report PDF 4.6 MB)

For additional information, contact:
Geology, Minerals, Energy, and Geophysics Science Center
U.S. Geological Survey
345 Middlefield Road, MS 901
Menlo Park, CA 94025-3591
http://geomaps.wr.usgs.gov/gmeg/

Part or all of this report is presented in Portable Document Format (PDF). For best results viewing and printing PDF documents, it is recommended that you download the documents to your computer and open them with Adobe Reader. PDF documents opened from your browser may not display or print as intended. Download the latest version of Adobe Reader, free of charge.

Suggested citation:

Fumal, Thomas E., Dawson, Timothy E., Flowers, Rebecca, Hamilton, John C., Heingartner, Gordon F., Kessler, James, Samrad, Laura, 2004, Photomosaics and Logs of Trenches on the San Andreas Fault at Mill Canyon Near Watsonville, California: U. S. Geological Survey Open-File Report 03-469, http://pubs.usgs.gov/of/2003/0469/.