PALEOSEISMOLOGICAL STUDIES AT THE UNIVERSITY OF NEVADA -- RENO (UNR) AND FUTURE OF EARTHQUAKE GEOLOGY

From purely traditional geology, my interests expanded in 1954 after four large earthquakes in Central Nevada that ruptured late Quaternary faults. UNR was an ideal setting for neotectonic studies, since early 1900s, UNR professors did pioneer research on Great Basin tectonics and historic faulting events. Although “Paleoseismology” is a new term, as noted by Bob Wallace, there were a long series of advances at UNR.

To expand studies, we added Alan Ryall, a seismologist, and upgraded and tripled the number of UNR Seismological Laboratory stations. Subsequent directors Jim Brune and John Anderson, continued to increase staff, students, and facilities, and kept close ties to geology.

In 1967, I invited Lloyd Cluff of Woodward-Lundgren Associates to contribute in an engineering geology class that fostered a strong tie between students and engineering geology practice. In 1969, we developed a new –and now widely used - method of low-sun-angle aerial photography to enhance fault detection and evaluation. We purchased standard aerial photo equipment to make our own 9"x 9" special photographs at detailed scales in many western U. S. active fault zones. The photo archive is widely used in subsequent studies and by many geologists from foreign countries that visited UNR. Our studies led to consulting with industry, governmental, and regulatory agencies, including design of important earthquake hazard projects in the world, subsidence and liquefaction potential in the Lake Maracaibo region, the Trans-Alaska Pipeline Project, numerous nuclear power plants around the world, and proposed Yucca Mountain nuclear waste site.

From 1977-1987, I refined the methods of Tocher and Bonilla that related earthquake magnitude to fault rupture parameters (maximum fault displacement, and surface rupture length) for more refined and quantitative methods to determine the size and character of past and future earthquakes, basic to paleoseismolical methods.

In 1985 the Center for Neotectonic Studies at UNR was founded. In 1989, Steve Wesnousky became its second Director, and his students are making making major paleoseismic studies in U. S. and around the world. The present development of paleoseismology clearly indicates that advancement, refinement, here and in other parts of the world will continue.