Pore-Pressure Response to Sudden Fault Slip for Three Typical Faulting Regimes

Abstract

Research Article| March 25, 2014 Pore‐Pressure Response to Sudden Fault Slip for Three Typical Faulting Regimes Xuejun Zhou; Xuejun Zhou Department of Geosciences, Virginia Tech, 1425 Perry Street, Blacksburg, Virginia 24061zhouxj@vt.edutjburbey@vt.edu *Also at National Energy Technology Laboratory–Regional University Alliance (NETL–RUA), 626 Cochrans Mill Road, P.O. Box 10940, Pittsburgh, Pennsylvania 5236‐0940. Search for other works by this author on: GSW Google Scholar Thomas J. Burbey Thomas J. Burbey Department of Geosciences, Virginia Tech, 1425 Perry Street, Blacksburg, Virginia 24061zhouxj@vt.edutjburbey@vt.edu *Also at National Energy Technology Laboratory–Regional University Alliance (NETL–RUA), 626 Cochrans Mill Road, P.O. Box 10940, Pittsburgh, Pennsylvania 5236‐0940. Search for other works by this author on: GSW Google Scholar Author and Article Information Xuejun Zhou *Also at National Energy Technology Laboratory–Regional University Alliance (NETL–RUA), 626 Cochrans Mill Road, P.O. Box 10940, Pittsburgh, Pennsylvania 5236‐0940. Department of Geosciences, Virginia Tech, 1425 Perry Street, Blacksburg, Virginia 24061zhouxj@vt.edutjburbey@vt.edu Thomas J. Burbey *Also at National Energy Technology Laboratory–Regional University Alliance (NETL–RUA), 626 Cochrans Mill Road, P.O. Box 10940, Pittsburgh, Pennsylvania 5236‐0940. Department of Geosciences, Virginia Tech, 1425 Perry Street, Blacksburg, Virginia 24061zhouxj@vt.edutjburbey@vt.edu Publisher: Seismological Society of America First Online: 14 Jul 2017 Online ISSN: 1943-3573 Print ISSN: 0037-1106 Bulletin of the Seismological Society of America (2014) 104 (2): 793–808. https://doi.org/10.1785/0120130139 Article history First Online: 14 Jul 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Xuejun Zhou, Thomas J. Burbey; Pore‐Pressure Response to Sudden Fault Slip for Three Typical Faulting Regimes. Bulletin of the Seismological Society of America 2014;; 104 (2): 793–808. doi: https://doi.org/10.1785/0120130139 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract The hydrological effects of earthquakes are determined by the style of fault displacement, rather than simply by the magnitude of the earthquake. In the past, many researchers used the analytical solution of Okada (1992) to estimate the pore‐pressure field, which is derived through the stress field by Skempton’s B coefficient, after the stress field is calculated from a given forced fault slip in Okada’s method (Okada, 1992). This approach is a one‐way coupling approach, as fluid has no effect on rock behavior, and Skempton’s B coefficient must be given separately to know the pore‐pressure field. We create a fault‐slip model in conjunction with a poroelastic model and present a new approach in which fault movement is a consequence of reduced friction occurring in a saturated porous medium. This model represents a numerical parallel to the traditional Okada’s approach, but with two advantages: (1) it is well suited for more complex geometries and heterogeneous formations for which analytical methods fail; (2) it is fully coupled so that fluid effects are also taken into account. This model shows that all three different faulting regimes exhibit completely different pore‐pressure change distributions in 3D space. The transient pore‐pressure change after a strike‐slip faulting event is axis symmetrical with respect to the imaginary vertical line passing through the epicenter and hypocenter, with increased and decreased areas evenly distributed in a juxtaposed pattern. The transient pore‐pressure changes associated with normal and thrust faulting all display a circular pattern on the model surface, with the largest pore‐pressure increase occurring at the epicenter for normal faulting and the largest decrease for thrust faulting. Many observed field phenomena have been explained in surprising detail by this model. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.