A Stochastic View of the 2020 Elazığ M_w 6.8 Earthquake (Turkey)
Abstract
Until the M_w 6.8 Elazığ earthquake ruptured the central portion of the East Anatolian Fault (EAF, Turkey) on January 24, 2020, the region had only experienced moderate magnitude (M_w < 6.2) earthquakes over the last century. We use geodetic data to constrain a model of subsurface fault slip. We adopt an unregularized Bayesian sampling approach relying solely on physically justifiable prior information and account for uncertainties in both the assumed elastic structure and fault geometry. The rupture of the Elazığ earthquake was mostly unilateral, with two primary disconnected regions of slip. This rupture pattern may be controlled by structural complexity. Both the Elazığ and 2010 M_w 6.1 Kovancılar events ruptured portions of the central EAF that are believed to be coupled during interseismic periods, and the Palu segment is the last portion of the EAF showing a large fault slip deficit which has not yet ruptured in the last 145 years.
Additional Information
© 2020 American Geophysical Union. Issue Online: 03 February 2021; Version of Record online: 03 February 2021; Accepted manuscript online: 17 December 2020; Manuscript accepted: 20 November 2020; Manuscript revised: 17 November 2020; Manuscript received: 10 September 2020. The slip model and data are available at https://doi.org/10.5281/zenodo.4114109. We thank an anonymous reviewer and Brendan Crowell for thorough reviews. We are very grateful to Diego Melgar and Brendan Crowell who calculated and provided the GNSS offsets for the coseismic deformation, and their relocated aftershocks catalog, which are both available in Melgar et al. (2020). GNSS data were made available from the Turkish National Permanent GNSS/RTK Network (TUSAGA‐Aktif/CORS‐TR administrated by General Directorate of Land Registry and Cadastre‐TKGM and General Directorate of Mapping‐HGM, Ankara, Turkey), thanks to Prof. Tuncay Taymaz and Prof. Taylan Öcalan. Initial aftershocks and phase‐arrival catalog has been provided by the Disaster and Emergency Management Presidency of Turkey (AFAD, 2020) for the period January 24, 2020 to February 11, 2020, and historical/background seismicity catalog was provided by BU‐KOERI (http://www.koeri.boun.edu.tr/sismo/2/en/) for Turkey from 1992 to 2020. This work contains modified Copernicus data from the Sentinel‐1A and Sentinel‐1B satellites provided by the European Space Agency (ESA) that are accessible at earth.esa.int/eogateway/. Original ALOS‐2 data and products are copyright JAXA and provided under JAXA ALOS Research Announcement 6 (RA6) project 3278. The Bayesian simulations were performed with the AlTar2 package (github.com/lijun99/altar2‐documentation, only accessible via github at publication date). The Classic Slip Inversion (CSI, github.com/jolivetr/csi, only accessible via github at publication date) Python library (Jolivet et al., 2014) was used to build inputs for the Bayesian algorithm, in particular to compute Green's functions. The python module PyDistMesh has been used to build the fault geometry (Persson & Strang, 2004). Figures were generated with the Matplotlib and Seaborn (10.5281/zenodo.1313201) Python libraries and with the Generic Mapping Tools library (Wessel et al., 2019). Mark Simons was partially supported by the National Aeronautics and Space Administration under Grant No. 80NSSC19K1499. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). Quentin Bletery work has been supported by the French government, through the UCA JEDI Investments in the Future project managed by the National Research Agency (ANR) ANR‐15‐IDEX‐01, the ANR S5 Grant No. ANR‐19‐CE31‐0003, and the ANR JCJC E‐POST Grant No. ANR‐14‐CE03‐002‐01JCJC.Attached Files
Published - 2020GL090704.pdf
Submitted - essoar.10504361.1.pdf
Supplemental Material - 2020gl090704-sup-0001-figure_si-s01.pdf
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Additional details
- Eprint ID
- 106274
- Resolver ID
- CaltechAUTHORS:20201026-094139044
- 80NSSC19K1499
- NASA
- 80NM0018D0004
- NASA
- ANR-15-IDEX-01
- Agence Nationale pour la Recherche (ANR)
- ANR-19-CE31-0003
- Agence Nationale pour la Recherche (ANR)
- ANR-14-CE03-002-01JCJC
- Agence Nationale de la Recherche (ANR)
- Created
-
2020-10-26Created from EPrint's datestamp field
- Updated
-
2023-06-01Created from EPrint's last_modified field
- Caltech groups
- Seismological Laboratory, Division of Geological and Planetary Sciences