High-Flying Experiments Demonstrate Potential of Balloon-Borne Infrasound Detection

18 April 2017-DENVER — Experiments conducted high in the skies over New Mexico suggest that balloon-borne sensors could be useful in detecting the infrasound signals generated by small, extraterrestrial debris entering Earth’s atmosphere, according to a report at the 2017 SSA Annual Meeting.

Infrasound, sometimes called low-frequency sound, is sound waves that occur at frequencies lower than the limit of human hearing. Infrasound signals can remain strong as they travel over large distances, making them useful for pinpointing the location and size of events such as nuclear explosions, meteorite strikes, volcanic eruptions and sometimes earthquake ruptures.

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Bombay Beach Highlights Difficulties in Earthquake Forecasting

18 April 2017-DENVER — In September 2016, about 100 small earthquakes between magnitude 2 and 4.3 took place in Bombay Beach, rattling the region in Southern California and raising questions about whether the swarm’s location near the southern end of the San Andreas Fault would trigger a larger earthquake.

In a presentation at the 2017 SSA Annual Meeting, U.S. Geological Survey seismologist Andrea Llenos discussed lessons learned from the 2016 Bombay Beach swarm, in particular the challenges in modeling swarms and communicating their risk to the public.

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SRL: 2017 Model Predicts Significant Chance of Earthquake Damage in the Central and Eastern U.S.

1 March 2017–A one-year seismic hazard model for 2017, from the U.S. Geological Survey, forecasts lower damaging ground shaking levels in the central and eastern U.S. compared to the previous forecast. Despite the recent drop in earthquake rates, Oklahoma and southern Kansas still face a significant risk of induced earthquake damage in 2017, according to the USGS report published March 1 in the journal Seismological Research Letters

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BSSA: Las Vegas Site Classifications Could Lower Costs

28 February 2017–Results of a massive new project to map and classify the earthquake shaking potential across most of the Las Vegas metropolitan area will help developers there build in safer and less expensive ways. The “Parcel Map” described 28 February in the Bulletin of the Seismological Society of America is the most extensive effort to date in the United States to map and classify soils based on their effects on earthquake shaking across an entire urban area with systematic, direct measurements at high density.

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