Imperial College London

Professor Julian J Bommer

Faculty of EngineeringDepartment of Civil and Environmental Engineering

Senior Research Investigator
 
 
 
//

Contact

 

+44 (0)20 7594 5984j.bommer Website CV

 
 
//

Location

 

Skempton BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Bommer:2020:10.1785/0220190345,
author = {Bommer, J and Montaldo-Falero, V},
doi = {10.1785/0220190345},
journal = {Seismological Research Letters},
pages = {2310--2319},
title = {Virtual fault ruptures in area source zones for PSHA: are they always needed?},
url = {http://dx.doi.org/10.1785/0220190345},
volume = {91},
year = {2020}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - Seismic source models for probabilistic seismic hazard analysis (PSHA), except when using zoneless approaches based directly on the earthquake catalog, invariably include areasource zones, even if active fault sources are modeled explicitly. Because most modern groundmotion prediction equations (GMPEs) employ sourcetosite distance metrics defined relative to extended fault ruptures rather than to the epicenter or hypocenter, it becomes necessary to generate virtual fault ruptures within the areasource zones to enable calculation of the correct distance of each earthquake scenario from the site of interest. For a sitespecific PSHA, the work of defining the virtual rupture characteristics such as strike, dip, and style of faulting, for more distant source zones, and the computational effort of simulating these ruptures for each earthquake scenario in the hazard calculations, may be unnecessary. Beyond a certain distance from the site, it can be demonstrated that the loss of accuracy introduced by modeling the individual earthquake scenarios as point sources rather than as extended ruptures is usually sufficiently small to allow the distance metric in the GMPEs to be treated as epicentral or hypocentral distance. Such simplifications can significantly increase the efficiency of the hazard calculations and also relieve the seismic source modelers of considerable effort to characterize virtual ruptures far beyond the host zone of the site. Treating earthquake scenarios in the more remote source zones as points also brings the additional benefit of avoiding problems that can arise with the largest magnitude scenarios leading to ruptures that approach the site in cases for which the ruptures are not constrained to remain within the source boundaries.
AU - Bommer,J
AU - Montaldo-Falero,V
DO - 10.1785/0220190345
EP - 2319
PY - 2020///
SN - 0895-0695
SP - 2310
TI - Virtual fault ruptures in area source zones for PSHA: are they always needed?
T2 - Seismological Research Letters
UR - http://dx.doi.org/10.1785/0220190345
UR - https://pubs.geoscienceworld.org/ssa/srl/article/91/4/2310/583742/Virtual-Fault-Ruptures-in-Area-Source-Zones-for
UR - http://hdl.handle.net/10044/1/78999
VL - 91
ER -