← Back to Sessions

A Fault Displacement Model Formulated in Wavenumber Domain

Session: Fault Displacement Hazard: New Data and Modeling Advances I

Type: Oral

Date: 4/22/2021

Presentation Time: 10:15 AM Pacific

Description: 

A new model for calculating the fault rupture hazard for sites crossing faults is presented in this study. The model is developed for the principal aggregate displacements, that is the sum of principal displacements perpendicular to the strike of the fault from overlapping ruptures, and it is formulated in the wavenumber domain following the Lavrentiadis and Abrahamson (2019) approach. The benefits of this approach are that it avoids the surface-rupture length normalization and that it considers the along strike correlation of displacements. The amplitude spectrum is expressed as a two-corner Butterworth filter, the phase-derivative distribution is defined as a normal distribution, and the site-specific slip variability as a mixture model of two normal distributions. The global scaling relationships are expressed in terms of the moment magnitude and surface-rupture segment length; the coefficients of the scaling relationships are estimated using the October 2020 version of the FDHI database, which contains 66 events of all styles ranging from M 5.0 to 8.2. One difference to other fault displacement models is that it is developed for individual segments and not for the entire rupture; to perform a PFDHA analysis for future scenarios, prediction equations for the rupture segment length and number of segments are also developed. The current model can replicate well the distribution of the displacement data across all along-strike bins. Comparisons with current fault displacement models and PFDHA calculations are also shown.

Presenting Author: Grigorios Lavrentiadis

Student Presenter: Yes

Authors