Spatial and Temporal Variations of Aftershock Activity of the 23 October 2011 Mw 7.1 Van, Turkey, Earthquake

Research Article| March 25, 2014 Spatial and Temporal Variations of Aftershock Activity of the 23 October 2011 Mw 7.1 Van, Turkey, Earthquake Pasquale De Gori; Pasquale De Gori aIstituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Via di Vigna Murata 605, 00143 Roma, Italypio.lucente@ingv.itpasquale.degori@ingv.it Search for other works by this author on: GSW Google Scholar Aybige Akinci; Aybige Akinci bIstituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 1, Via di Vigna Murata 605, 00143 Roma, Italyaybige.akinci@ingv.it Search for other works by this author on: GSW Google Scholar Franceso Pio Lucente; Franceso Pio Lucente aIstituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Via di Vigna Murata 605, 00143 Roma, Italypio.lucente@ingv.itpasquale.degori@ingv.it Search for other works by this author on: GSW Google Scholar Tuğbay Kılıç Tuğbay Kılıç cTurkish Republic Disaster and Emergency Management Presidency, Earthquake Department, Ankara, Turkeytugbay.kilic@afad.gov.tr Search for other works by this author on: GSW Google Scholar Bulletin of the Seismological Society of America (2014) 104 (2): 913–930. https://doi.org/10.1785/0120130118 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 Pasquale De Gori, Aybige Akinci, Franceso Pio Lucente, Tuğbay Kılıç; Spatial and Temporal Variations of Aftershock Activity of the 23 October 2011 Mw 7.1 Van, Turkey, Earthquake. Bulletin of the Seismological Society of America 2014;; 104 (2): 913–930. doi: https://doi.org/10.1785/0120130118 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 On 23 October 2011, an Mw 7.1 earthquake struck the Van Lake region of eastern Turkey; causing vast damage in the cities of Van and Erciş. The mainshock was followed by a large number of aftershocks, which define a 60–70 km long and 30–35 km wide northeast–southwest‐trending structure, in agreement with the source rupture models derived for the main event. In this paper, we take advantage of this large data set to examine the spatial and temporal properties of the Van earthquake aftershock activity. We derive the spatial distribution of b‐value of the Gutenberg–Richter law, as well as complementary seismicity parameters, along the surface projection of the fault plane. Recent studies have been published on the same issue, presenting controversial and sometimes opposite results. With respect to previous studies, we rely on a possibly higher quality catalog of relocated earthquakes. Furthermore, we adopt a more conservative approach, excluding from the analysis the first few days of data, until the Mc reaches a stable completeness threshold; finally, we conduct statistical tests in order to check the significance of the spatial and temporal variation of b‐value across the fault plane.Calculations are made for the complete catalog and for two independent aftershock subcatalogs, after which a stable magnitude of completeness Mc is reached. For each catalog, we correlate the observed b‐value patterns with slip distribution models of the mainshock obtained through the inversion of seismological and geodetic data. Overall, the b‐values vary from 0.9 to 1.5 along the Van rupture fault zone. The higher b‐values (>1.1) are observed around the epicenter of the mainshock characterizing the higher coseismic slip area on the fault projection. Low b‐values are concentrated at the peripheral portion of the fault, away from high‐slip patches. Moreover, the b‐value distribution over the fault plane undergoes significant variation throughout the aftershock sequence. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.