“Thoughts on the USGS role in the Intermountain West, in the context of hazard evaluation in extensional settings” John G. Anderson Director, Nevada Seismological Laboratory Presentation to Scientific Earthquake Studies Advisory Committee September 13, 2004 Jackson Hole, Wyoming
Outline • Background • Scientific issues • Organizational needs and concerns
About 25% of the total Pacific – North America plate motion takes place east of the Sierra Nevada mountains
20: 12.9% 5: 28.5% 32: 8.9% 1: 66.3% 4: 29.6% 3: 30.6% 12: 20.1% 2: 40.0% Population growth rate, 1990-2000 US Census Bureau Annualized Earthquake Loss Ratio at the County Level Source: nationalatlas.gov, FEMA366, US Census Bureau
Conclusions on hazard and risk • The total risk in this region is small compared to California. • Individual households or businesses in the Basin and Range states face risks comparable to or greater than those affecting many residents of California. • The resident of Reno faces a higher hazard than the resident of San Diego. • The population is growing fast.
Scientific Issues • Monitor the hazard • ANSS & other networks • Describe the hazard • Seismic hazard analysis • Understand the hazard • Basin and Range Earthquake Center
Comment on USGS Role • The USGS has pursued essential research targets. • Extensive body of important results • Commend Mark Peterson for reaching out to get community feedback on research priorities • Need for better outreach
Monitor the Hazard: ANSS • Has already made a big difference • Defer to other speakers on the agenda • Engineering community in Nevada remains keenly interested. • Concerns about stability of funding • Question related to structural instrumentation: Once a structure is selected to be instrumented, who will install and maintain the instruements? • Encourage vigorous support for ANSS from this committee and all levels of the USGS leadership. • We are ready to do our part to support you.
Monitoring • Thought: USGS (ANSS) is not the only agency supporting seismic monitoring in the region. • DOE (might spend more) • NSF: not only Earthscope • Other federal agencies • We appreciate USGS for it’s commitment and long-term perspective, while other agencies are focused on specific problems and can be unreliable. • Encourage USGS to develop ANSS in a way that is consistent with long term planning for network operators, in the context of the multiple sources of funding.
ANSS portable arrays • Site response at long periods in urban areas: temporary (& a few permanent) deployment of broadband seismometers. • What are the plans? • Recognize that structures are highest ANSS priority. • Especially important in our region. (Basins, Activity rate) • We at UNR believe those instruments will play an important role in hazard reduction, and are willing to host one of the portable arrays that would be used between earthquakes to focus on site characteristics.
Instrumentation Beyond ANSS • New paradigm on how to create a widely distributed strong motion network • No chance for Federal funding to support strong motion at the density needed to solve all the problems. • Japanese networks: Yokohama, Tokyo • Support development of new approaches • Embrace it if private industry comes up with a way.
Describe the Hazard • National Seismic Hazard Maps: Exceptionally valuable! • As USGS already recognizes, need to continue improve.
Source: Geoff Blewitt, Corne Kreemer, data Mark Coolbaugh, plot
Nevada Priorities • Characterize faults, emphaisize near urban areas • Velocity structure • Create “Community models” for both • Ground motion prediction • Source physics • Improve and test seismic hazard estimates. • Scenarios to communicate results
Understand the hazard • Needed: Basin and Range Earthquake Center • Model after Southern California Earthquake Center • Goal: accelerate progress to quantitative description of the hazard • Promote Earthscope goals. • Proposal to NSF / Earthscope for a Great Basin center CVM/CFM
Characteristics of SCEC to copy • Natural laboratory. In BREC case, the laboratory is extensional tectonics. • Universities and USGS • Annual meeting • Community products (crustal motion, velocity, faulting) • Vision of bringing all elements of earthquake science into a predictive science
Basin and Range Earthquake Center • May involve some parties outside of geophysics • UNR has a structures lab, • close collaboration with Seismology • Interest in collaboration, supported by UNR administration Response of a bridge column to 1.35 x Rinaldi north component
What else can USGS do? • Nevada Seismological Laboratory would welcome a USGS personnel to work on network seismology. • Western Great Basin • Mammoth eventually • Mendenhall postdoc? • Other Basin & Range universities may think the same
What else can USGS do? • Earthquake Prediction Evaluation Council • Almost needed one this past spring.
Summary • The region has a significant and growing earthquake problem. • We have a clear idea of what needs to be done. Resource issues. • It is time to consider the advantages of forming a Basin and Range Earthquake Center