1855 and 1991 Surveys of the San Andreas Fault: Implications for Fault Mechanics
Two monuments from an 1855 cadastral survey that span the San Andreas fault in the Carrizo Plain have been right-laterally displaced 11.0 ± 2.5 m by the 1857 Fort Tejon earthquake and associated seismicity and afterslip. This measurement confirms that at least 9.5 ± 0.5 m of slip occurred along the main fault trace, as suggested by measurements of offset channels near Wallace Creek.
Grant, L.B. and Donnellan, A., 1994, 1855 and 1991 surveys of the San Andreas Fault; implications for fault mechanics: Bulletin of the Seismological Society of America, v. 84, p. 241-246.
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Email Address Created for Land Exchange Questions
The Southwestern Region Office of Lands and Minerals Management is overseeing and administering the land exchange and appraisal process which includes the 2,422-acre Oak Flat Federal Parcel. All questions about the land exchange and appraisal process should be emailed to SM.FS.rcexinfo@usda.gov
Programmatic Agreement Info
To comply with Section 106 of the National Historic Preservation Act, the Tonto National Forest developed a Programmatic Agreement (PA) and included it in Volume 5, Appendix O of the final EIS. The PA was created in cooperation with the Advisory Council on Historic Preservation, the State Historic Preservation Office, tribes and other consulting parties. The PA contains an agreed upon process for identifying, evaluating and addressing adverse effects to historic properties associated with this undertaking.
To review Volume 5 and the PA, Download Vol 5 PDF, 27 MB.
Forest Service Point of Contact
John Scaggs
Tonto National Forest
john.scaggs@usda.gov
Apache Leap Special Management Area
Apache Leap SMA website