Embargoed: Contents not for release until 12:01 a.m. the day of session. All times Pacific Standard Time. All sessions will be held at the Marriott Downtown Waterfront Hotel in Portland, Ore. Press may receive complimentary registration at the Ballroom Lobby.
The Seismological Society of America (SSA) is an international scientific society devoted to the advancement of seismology and its applications in understanding and mitigating earthquake hazards and in imaging the structure of the Earth.
For a searchable database of abstracts and additional meeting information visit: http://www.seismosoc.org/meetings/2010/program.php
Thursday, April 22
Operational Earthquake Forecasting
8:30 a.m. – Noon, Salon A
The public needs information about future earthquakes. The goal of operational earthquake forecasting – quantifying the likelihood that a seismic event will occur in the near term – is to provide communities with information about seismic hazards that can be used to make decisions in advance of potentially destructive earthquakes. This session reports on the status of the science of earthquake forecasting.
- What is operational earthquake forecasting and how does it differ from alerts to the public about other hazards? Gordon Woo, Risk Management Solutions, United Kingdom, woo@rms.com
- In the aftermath of the April 2009 (m 6.3) L'Aquila earthquake, Italian authorities appointed an international commission to consider the value of both prediction (stating an exact time, location and magnitude of an earthquake) and forecasting (giving the probability of an earthquake) methods of earthquakes. In this presentation, the chair of the international commission will use the commission's findings and recommendations as the basis for speculation on future enhancements and refinements to operational earthquake forecasting in Italy, California and elsewhere. Tom Jordan, University of Southern California and head of the Collaboratory for the Study of Earthquake Predictability, tjordan@usc.edu.
- U.S. and international governments are reconsidering their automatic alert and activation levels, as well as response procedures. The proposed Earthquake Impact Scale (EIS) is based on two complementary criteria. One, based on the estimated cost of damage, is most suitable for domestic events; the other, based on estimated ranges of fatalities, is generally more appropriate for global events. Both simple and intuitive color-coded alerting criteria are presented. David Wald, U.S. Geological Survey, wald@usgs.gov.
- Case study: The state of operational earthquake forecasting in Italy, pre- and post- 2009 L'Aquila earthquake. Warner Marzocchi, Istituto Nazionale di Geofisica e Vulcanologia (INGV), warner.marzocchi@ingv.it
- A report on recent efforts by the Collaboratory for the Study of Earthquake Predictability, which is testing and evaluating short-term earthquake forecasts in four different testing centers around the globe. Danijel Schorlemmer, USC, ds@usc.edu
Near-Surface Deformation Associated with Active Faults
8:30 a.m. – Noon, Salon F
Seismic hazard assessments rely on an accurate understanding of the likely recurrence of earthquake behavior. Seismologists use a range of tools to examine the changes to the Earth's surface and near-surface from active faults. Tools, such as remote sensing technology, help document evidence of past earthquakes and current seismic creep.
There is debate as to the seismic hazard associated with the New Madrid Seismic Zone (Central U.S.), which generated giant earthquakes in 1811 and 1812. Some investigators interpret GPS data as evidence that no strain is being accumulated across the faults, suggesting far less seismic hazard in the area than previously thought. This presenter argues that there are observable GPS motions at the surface. Moreover, he suggests several models that allow significant strain at depth, while limiting deformation of the Earth's surface. Oliver Boyd, U.S. Geological Survey, olboyd@usgs.gov
Earthquake Debates
1:30 – 5 p.m., Salon F
Ever-evolving understanding of earthquake behavior is challenging long-held ideas. Seismologists will debate important issues in earthquake science, including whether Gutenberg-Richter behavior in a large region suggests similar behavior on individual faults. As seismologists create more complex programs that simulate the occurrence of earthquakes, is there a limit to their value in developing hazard assessments?