Understanding Injection-induced Seismicity Effects of Fault Damage Zones: Beyond Poroelastic Models
Abstract
The rise in earthquake activity attributed to anthropogenic causes stresses the need for hazard mitigation decision-making frameworks that are based upon realistic models giving reliable predictions.
A set of recent efforts have addressed the problem of modeling injection-induced fault slip using poroelastic coupled schemes, often failing to accurately predict fluid movement and pore pressure perturbations in the evolving fault damage zone, proven to significantly affect and be affected by fault stresses and rupture. We go beyond conventional poroelastic simulations by incorporating the nonlinear behavior of the subsurface material, which controls dominant inelastic deformation. We differentiate between fault rupture planes, damage zone, and host rock by defining a set of heterogeneous characteristic hydromechanical properties within each damage zone element, and predicting the evolution of the magnitude and extent of such anomalies in the vicinity of fault friction planes. We analyze pore pressure and stress state changes spatiotemporally by applying a continuum damage mechanics workflow to our computational simulation framework, which allows to integrate multi-scale physical processes of flow, deformation, and crack growth. We conclude with safe injection design implications in terms of well placement and flow rate under various in-situ conditions.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.S21A..07S
- Keywords:
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- 7209 Earthquake dynamics;
- SEISMOLOGYDE: 7223 Earthquake interaction;
- forecasting;
- and prediction;
- SEISMOLOGYDE: 7230 Seismicity and tectonics;
- SEISMOLOGYDE: 8168 Stresses: general;
- TECTONOPHYSICS