WITHDRAWN Development of Non-ergodic Ground-Motions Model for Induced Seismicity by Considering Field-Specific Source and Site Effects
Description:
WITHDRAWN We present the development and application of a fully non-ergodic ground motion model (GMM) tailored to induced earthquake characteristics and operation needs of O&G fields. Non-ergodic GMMs are a promising development in probabilistic seismic hazard analysis as they offer the potential to reduce the aleatory variability that controls the seismic hazard, especially in larger return periods. This reduction in aleatory variability is accompanied by epistemic uncertainty in regions with sparse recordings or a systematic shift in the median ground motion in regions with dense recordings. The non-ergodic GMMs is developed as a spatially Gaussian Process model in which the systematic source and site effects are modeled with spatially varying coefficients that depend on the coordinates of the source and the site, and the systematic path effects are modeled by cell-specific geometrical spreading and anelastic attenuation.
While some nonergodic ground motion models have been developed for natural earthquakes, they have not been extensively tested at regions in which the seismic hazard is controlled by induced events, such as O&G fields and geothermal energy harvesting sites. These regions are often well characterized and densely instrumented but are dominated by small-magnitude triggered by field operations. Using information already collected at O&G fields, here we specifically: (i) use the dense instrumentation to identify repeatable effects of induced earthquakes and their temporal variability; (ii) combine high-resolution subsurface characterization to identify repeatable path effects better; (iii) use a parametric study of dynamic rupture models to improve the prediction of source effects by accounting for the source complexity of small magnitude induced events and (iv) use the known locations of stress perturbations induced by field operations and the short-term return periods of induced events to develop near-real-time updating of the presented GMMs.
Session: Advances in Probabilistic Seismic Hazard Analysis and Applications
Type: Oral
Date: 4/19/2023
Presentation Time: 11:30 AM (local time)
Presenting Author: Grigorios Lavrentiadis
Student Presenter: No
Invited Presentation:
Authors
Grigorios Lavrentiadis Presenting Author Corresponding Author glavrent@caltech.edu California Institute of Technology |
Elif Oral elifo@caltech.edu California Institute of Technology |
Domniki Asimaki domniki@caltech.edu California Institute of Technology |
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WITHDRAWN Development of Non-ergodic Ground-Motions Model for Induced Seismicity by Considering Field-Specific Source and Site Effects
Category
Advances in Probabilistic Seismic Hazard Analysis and Applications