Best practices book - Flipbook - Page 319
Scope
Earthquake faults within the Las Vegas Valley are under-characterized with regard to
their seismic hazard, particularly considering their proximity to the densely populated
areas of Clark County. An important consequence of the under-characterization is that
nearly all the known Quaternary faults in Las Vegas Valley are classified as "Class B
faults" meaning that too little information about the faults is known for them to be
considered in the analysis for the National Seismic Hazard Map. Consequently, the
National Seismic Hazard Map, which is a basis for building codes, does not include
these faults in the seismic hazard calculation despite the fact that we know they are
present.
To address the issue of under-characterization of earthquake faults within the Las Vegas
area and the resultant inaccuracy in the seismic hazard calculation and analysis, the
study will c o n s i s t o f an accelerated data collection and analysis program that will
provide the needed data, fault parameters, and analysis for · more accurate calculation of
the seismic hazard. The proposed project will bring the understanding of the earthquake
hazard potentially posed by faults in Las Vegas Valley up to the level of other
seismically active areas in the U.S. and stabilize the calculated size of the hazard. The
stabilization is central to avoiding frequent changes in the seismic aspects of the
building code. A combination of scientists from the Nevada Bureau of Mines and
Geology (University of Nevada, Reno), the University of Nevada, Las Vegas, and
the U.S. Geological Survey will work together to develop characterization within a
four-and-a-half-year timeframe. The proposed work is divided into tasks that
culminate with the earthquake source characterization of the faults.
Costs / Benefits:
The major benefits of this analysis besides the technical output is the potential increase of
safety to the public as well as the cost savings to design/construction of major projects due
to a better understanding of the potential seismic hazards in the valley. The proposed
work is divided into tasks that culminate with a m o r e d e f i n e d earthquake
source characterization of the faults. This characterization will include the locations of
earthquake faults, the potential magnitudes of earthquakes along these faults, and how
often earthquakes can occur. The results can be used for (1) building codes in Clark
County, (2) input to the National Seismic Hazard Map, (3) site-specific engineering
studies in the county, (4) emergency response planning scenarios, and (5) other
seismically related purposes. Although putting a cost savings to these results is difficult at
this time, the savings have the potential be substantial.
Attached Documents:
-Proposed Scope of Work and timeframes
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