Philip A. Pearthree

This report presents an assessment of the seismic hazard associated with the Sugarloaf fault, which crosses State Route (SR) 87 near Mesquite Wash in central Arizona. The Sugarloaf fault is a 20 km (12 mile) long, northwest- to north-trending normal fault with displacement down to the east. We conducted a multi-faceted investigation in order to evaluate the late Quaternary behavior of the Sugarloaf fault and assess the seismic hazard associated with it.

This report is a compilation of available data on Quaternary faults in Arizona as of the summer of 1998. These data were compiled as part of a effort to compile data and map information on Quaternary faults throughout the world, which is being overseen by Michael Machette of the U.S. Geological Survey.

Comments from each of the six public hearings are available for viewing. Note that the public comment period is now closed.

Public Hearing Comments

Draft EIS

The draft EIS public comment period closed November 7, 2019. All 30,000+ comment submittals are now under review for consideration in the compilation of the final EIS.

Media & General Info

Point of Contact
John Scaggs
Tonto National Forest
john.scaggs@usda.gov

Apache Leap Special Management Area
Apache Leap SMA website