IAVCEI 2013 Scientific Assembly - July 20 - 24, Kagoshima, Japan
Forecasting Volcanic Activity - Reading and translating the messages of nature for society

3P2_4G-O14

Room A4

Date/Time: July 23 18:30-18:45

New USGS California Volcano Observatory partners with California Emergency
Management Agency for hazard identification, risk assessment, and preparedness
Margaret Mangan1 , Johanna Fenton2 , Andrew Calvert1 , Michael Clynne1 , Julie Donnelly-Nolan1 , Wes
Hildreth1 , Heather Wright11

US Geological Survey, California Volcano Observatory, US, 2 California Emergency ManagementAgency, Preparedness Division, US
E-mail: mmangan@usgs.gov

The USGS California Volcano Observatory (CalVO) was established in February 2012 to improve coordination
with federal, state, and local emergency managers during volcanic crises, and create new opportunities for volcanic
hazard awareness and preparedness. CalVO is an outgrowth of the former USGS Long Valley Observatory butwith the broader responsibility of monitoring all potentially threatening volcanoes in California, most notably Mount
Shasta, Medicine Lake, Clear Lake Volcanic Field, and Lassen Volcanic Center in the north, Long Valley Calderaand Mono-Inyo Craters in east-central California, and Salton Buttes, Coso Volcanic Field, and Ubehebe Craters inthe southern part of the state.

California is geologically diverse, exhibiting a range of volcanism resulting from subduction, crustal thinning,and extensional rifting in the northern, central, and southern parts of the State, respectively. More than ten
eruptions have occurred in the last 1,000 years, most recently at Lassen Volcanic Center (1666 C.E. and1914-1917 C.E.) and Mono-Inyo Craters (c. 1700 C.E.). The Long Valley Caldera and Mono-Inyo Craters region
underwent several episodes of heightened unrest over the last three decades, including intense swarms of
volcano-tectonic earthquakes, rapid ground uplift, and dangerous CO2 emissions. Both Medicine Lake and Lassen
are subsiding at the appreciable rate of 8-10 mm per year, and along with Clear Lake, sporadically experiencelong-period, low frequency earthquakes related to migration of magma or hydrothermal fluid. With the exceptionof Ubehebe Craters, all California "watch list" volcanoes support vigorous hot springs, boiling mudpots and (or)fumarolic activity, and four are geothermal power producers.

In addition to monitoring, a major component of the field-based research conducted by observatory volcanologists
funnels into the creation of comprehensive and authoritative volcanic hazard assessments. Each assessment
is a dynamic document, refined and updated as new data are collected and interpretations become better
constrained. To maximize the societal impact of USGS volcano hazard assessments, CalVO is partnering with
the California Emergency Management Agency (CalEMA), the government entity responsible for coordinatingdisaster preparedness, response, and recovery efforts within the state. The USGS-CalEMA partnership will resultin a three-part volcano annex to the California Statewide Emergency Plan that includes hazard identification, risk
analysis, and an emergency operations plan. The volcano annex will integrate natural hazard and socio-economic
information in a format readily accessible to decision-makers.

©IAVCEI 2013 Scientific Assembly. All rights reserved.

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