Earthquake Monitoring

AZGS joined representatives from several dozen states, FEMA, the US Geological Survey, and Washington state emergency managers at last week's National Earthquake Program Manager's meeting in Seattle, Washington. The principal objective was to share information, technologies, successes and challenges of each state's earthquake preparedness and readiness.

Key topics, included:

• Challenge of inventorying unreinforced masonry buildings (URM) that perform poorly during earthquakes.
• Early alert systems of California, Oregon and Washington.
• USGS efforts to convey information on the Hayward Fault - Haywired.
• Challenges to building and sustaining an active earthquake management program.
• Innovative approaches to conducting earthquake outreach programming.

Over three days, we had ample opportunities to network with our peers and FEMA and USGS colleagues.

The chief takeaway for Arizona is the need to establish an Arizona Seismic Safety Commission to engage the many federal, state, local, tribal jurisdictions and the NGOs and private industry to shape a seismic safety program that promotes resiliency  and recovery. No small task.

Work with Western States Seismic Policy Council to flesh out the make-up, authority, and responsibilities of an Arizona Seismic Safety Commission.

AZGS's Jeri Young Ben-Horin investigating a stand of the Oak Creek Canyon fault exposed near Flagstaff, Arizona. The fault trace is bearing N40E and is nearly vertical.

A magnitude 5.3 earthquake occurred about 29 kilometers southwest of Santa Cruz Island, California, at 19.29 UTC on 5 April 2018.  The event was recorded by our AZGS Broadband Seismic Network. The image below shows seismograms from five Arizona broadband stations (JY Ben-Hurin).  

Jeri Young-Ben Horin and Brian Gootee just kicked off a field investigation of the Mead Slope fault along the south shore of Lake Mead. They spent several days this past week examining the fault and produced this short 40-second video to briefly describe their research.  Mead Slope Fault, Lake Mead, AZ.

AZGS participated today in FEMA's National Earthquake Hazard Reduction Program Earthquake Program Managers teleconference. FEMA reinstated direct NEHRP funding to the states in 2017-2018. Arizona was one of 14 states to participate last year. Today's meeting was to review state participation for the next fiscal year.

The Basin and Range Province Earthquake Working Group met Thursday 2/15 in Salt Lake City. The Utah Geological Survey hosted the meeting and the USGS Earthquake Hazards Reduction Program provided financial support, which allowed representatives from all the Intermountain West states (including AZ) to attend. The primary purpose of the meeting was to share information and ideas about improving the science behind earthquake hazard assessment in the Basin and Range Province.

Much more research and investigations into Quaternary faulting have been completed in some states (Utah, California) than in the rest of the Intermountain West. We look to them as guides for future earthquake research, integrating research into seismic hazard assessments, and disseminating information about earthquake hazards to the public.

P. Pearthree (Arizona State Geologist)

AZGS seismic stations were among 300+ stations that provided insight into the precise location of today's M7.9 Alaskan earthquake. The NEIC/USGS used data from our stations at Grand Canyon's North Rim, Tonto, Hannagan Meadow, Duncan, and Douglas. Seismograms from AZGS stations (Jeri Y-BH).