The 1906 Mw7.8 earthquake on the N. San Andreas Fault marked the birth of modern earthquake science. For the first time, the effects and impacts of a major seismic event were systematically investigated and documented including the entire 300-km-long surface rupture and surface offsets. The full extent of the San Andreas fault throughout California was also mapped. Comprehensive study of seismic intensity showed the strongest shaking occurred in areas of “made land” (fill) and soft sediment, including China Basin and present day Marina districttwo San Francisco neighborhoods heavily damaged again in 1989. Damage to structures showed destruction was closely related to building design and construction--a painful lesson oft repeated around the world. Interpretation of repeated surveying data and surface offsets led Henry Reid to propose the elastic rebound hypothesis--that earthquakes represent sudden release of elastic energy along a fault resulting from a cycle of slow strain accumulation produced by relative displacements of neighboring portions of the crust--still accepted today with minor modifications, even though the basis for large-scale horizontal displacements wasn't established until the plate tectonic revolution five decades later. Looking to the future, a dense array of continuous GPS recorders in N. California, part of EarthScope's Plate Boundary Observatory, can search for fault interactions and determine if an acceleration of strain rate precedes the next big earthquake as it may have prior to 1906.
Mary Lou Zoback is currently a Senior Research Scientist with the USGS Western Earthquake Hazards Team, Menlo Park, CA and serves as the Regional Coordinator for the USGS Northern California Earthquake Hazard Program. She is also chair of the Steering Committee for the “1906 Earthquake Centennial Alliance”. Zoback joined the USGS in 1978 after receiving her Ph.D. in geophysics from Stanford University.From 1999-2002 she was Chief Scientist of the USGS Western Earthquake Hazards team. Her primary research interest is the relationship between earthquakes and stress in the earth's crust. Areas of study include the San Andreas fault system, the Basin and Range Province of the western United States, as well as intraplate regions such as the central and eastern United States. Dr. Zoback has served on numerous national committees and panels on topics ranging from continental dynamics, storage of high-level radioactive waste, and science education. She is active in several professional societies, she is past-President of the Geological Society of America and currently serves on the Council of the National Academy of Sciences. Dr. Zoback was awarded the American Geophysical Union's Macelwane Award in 1987 for "significant contributions to the geophysical sciences by a young scientist of outstanding ability" and in 1995 was elected into the National Academy of Sciences.
This is the fifth lecture in series sponsored by Stanford University's Quake '06 Alliance and University of California, Berkeley commemorating the 1906 Earthquake that cause massive destruction at Stanford University. The series will focus both on the historical and social perspectives of the 1906 Earthquake as well as the earth science, earthquake engineering, preparedness and disaster relief in order to prepare us for future earthquakes.