Source: U.S. Geological Survey Open-File Report 03-187, "Preliminary Paleomagnetic Results from the Coyote Creek Outdoor Classroom Drill Hole, Santa Clara Valley, California" by Edward A. Mankinen and Carl M. Wentworth. http://pubs.usgs.gov/of/2003/of03-187/of03-187.pdf
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Approximate times of some of the most commonly reported geomagnetic excursions of the Brunhes Normal Polarity Chron. * Highlighted excursions are those most likely to be found in the western U.S. * Possible correlations of these to a sketch of