Best practices book - Flipbook - Page 329
Task 5 - Earthquake Potential of Late Quaternary Faults
The earthquake potential analysis will formally combine the different earthquake sizes and
recurrence intervals to come up with preferred estimates for each potential earthquake source.
The synthesis is complicated because of the potential for multi-fault earthquake ruptures, as well
as ruptures along individual faults. A formal analysis is required to avoid errors such as double
counting earthquakes (counting too many earthquakes for a fault that is not capable of such
activity). Uncertainties in fault parameters will also be incorporated into analysis.
A state-of-the-art strategy for the earthquake potential analysis will include a logic tree tool for
combining multiple sources of data and uncertainties. This analysis uses a relative weighting of
different parameters and formally combines them into resultant values. The logic tree technique
offers a transparent, statistically consistent way of analyzing earthquake data. The final results
will be the earthquake potential of individual faults and collectively of all earthquake faults in
Las Vegas Valley.
The fault map produced in Task 2 and the earthquake magnitude estimations for the faults (Task
3) will be combined to generate potential surface rupture hazard maps for Las Vegas Valley.
These maps will indicate the locations of fault traces, the activity of those faults, and the size of
their potential offset during an earthquake. This information can be used so buildings and
facilities can be carefully placed to avoid surface rupture during an earthquake and so facilities
or infrastructure that must cross faults, such as pipelines, can be designed for the potential offset
that might occur during an earthquake. This mitigation opportunity will help minimize disruption
and economic loss from a surface-rupturing earthquake.
Task 5 consists of five subtasks:
Task 5.1 - Develop Earthquake Potential Estimation Strategy,
Task 5.2 -Logic Tree Analysis,
Task 5.3 -Develop Earthquake Magnitude and Recurrence Values,
Task 5.4 - Develop Earthquake Surface Rupture Hazard,
Task 5.5 - Surface Rupture Map and Report.
Task 5 will be conducted during the fourth year of the project and will use all the data collected
in the earlier years.
For official use only
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BEST PRACTICES | 320
Date of Review: _____________
