Regional Review

Intermountain West (IMW) Region

Walter Arabasz Regional Coordinator Nov. 21, 2005

ANSS Intermountain West Region AZ CO UT NV NM ID MT WY Population* 5.7 million 4.6 million 2.4 million 2.3 million 1.9 million 1.4 million 0.9 million 0.5 million 19.7

*July 2004

IMW Region...



Large (~3 times larger than CA+WA+OR)



Fastest growing region in the Nation



Has concentrated EQ risk in scattered metropolitan areas, in part due to large federal landholdings (83% NV, 65% UT, 62% ID, 50% WY, 45% AZ, 36% CO, 34% NM, 28% MT)



Has compelling needs for improved seismic monitoring associated with (a) dramatic population growth in metropolitan areas at moderate to high seismic risk and (b) large gaps in regional coverage of seismically active areas

IMW Organizational Structure Regional Advisory Committee (18 members

—2 from each state, except 1 from AZ, and 3 “at large”)

Regional Working Group (

16 members, incl. rep’s from

all major networks and every state)

state level advisory committees UT 12 members, incl. 10 engrs NV ~17 members CO ~20 members

Regional Coordinator: Walter Arabasz Invited participant in NIC to represent NV: John Anderson (alternate, Glenn Biasi)

IMW Web site: www.seis.utah.edu/anss

Status of ANSS Implementation National Backbone

Strong-Motion Stations

Pink = PGA



16%g, 2% in 50 years Purple = 50-km radius

545 stations (283 SM, 59 BB) MT ID WY

167 UU 130 UNR 104 NSMP

UT NV CO NM AZ Black = “Have Not” states

UUSS Regional/Urban Seismic Network Regional short-period/broadband net Urban strong-motion network

> 216 stations ~ 517 channels

ShakeMap in Utah Region



ShakeMaps in Wasatch Front Area



ShakeCast



Expanding ShakeMap capability to entire Utah region

USGS Global ShakeMap

Uncalibrated Scenario ShakeMap for M7.2 EQ on Teton fault

Regional Advisory Committee:

Patchquilt of seismic networks —both stably funded and unstably-funded

1.

Most important IMW need for regional seismic monitoring is a strategic regionwide plan for dealing with EQ geography, uniform recording, and response

Regional Advisory Committee:

• • • •

2.

Need to help “have not” networks in IMW HOW?

Convene long-overdue mtg between ANSS mgrs, IMW network operators, and IMW RAC “Mutual-aid agreements among nets & NEIC, especially where network staffing is very small Provide improved software for efficient earthquake analysis Assist with critically-needed technical support (more)

Regional Advisory Committee:

HOW? (cont’d)

•

Address ways to provide critical info —both via Web and via personal contacts —to information outlets and/or to key persons in “have not” states to ensure that they can reliably inform governors, high-level decision-makers, and local media during earthquake situations

Regional Advisory Committee:

HOW? (cont’d)

•

Explore avenues for funding —including ways that unified political activism among IMW states can gain support for improved network monitoring in seismically active states that are disadvantaged under ANSS

Regional Advisory Committee:

3.

Need for availability of portable instruments to augment inadequate network coverage (with sensible “business rules” to govern when instruments will be deployed and what logistic and financial support may be available)

Regional Advisory Committee:

4.

Need to capture strong-motion data for large normal-faulting Eqs, even if it means instrumenting areas with low population density

Regional Advisory Committee:

5.

States without their own seismic nets need clearer understanding from ANSS how, and to what level, seismic monitoring is carried out within their state using national backbone stations (e.g., Is small-magnitude EQ activity in Colorado being routinely located?)