CSV catalog file and origin-time and depth plots of preliminary NLL-SSST-coherence earthquake relocations for the 2023 Mw 7.8 and Mw 7.6, Kahramanmaraş - Gaziantep, Turkey earthquake sequence (17,248 events, M≥1.5, 2023-01-01 to 2023-03-24). NLL-SSST-coherence (Lomax and Savvaidis, 2022) is an enhanced, absolute-timing earthquake location procedure which 1) iteratively generates spatially varying travel-time corrections to improve multi-scale location precision and 2) uses waveform similarity to improve fine-scale location precision. Preliminary relocations performed with phase arrival data available from AFAD (https://deprem.afad.gov.tr/event-catalog) on 2023-03-24. Higher precision NLL-SSST-coherence relocations should be available when reviewed, merged, seismic phase arrival data is available from AFAD, KOERI (https://eqe.boun.edu.tr) and other networks. Seismic velocity model is a smoothed version of the "Final 1-D" velocity model from: Acarel, D., Cambaz, M.D., Turhan, F., Mutlu, A.K. & Polat, R., 2019. Seismotectonics of Malatya Fault, Eastern Turkey. Open Geosciences, 11, 1098–1111. Available at: https://doi.org/10.1515/geo-2019-0085. [For relocations of events starting from 2020-01-01 through 2023-03-04 and including the 2020 Mw 6.8 Elazığ, Turkey sequence, see v1.0 of this dataset: https://doi.org/10.5281/zenodo.7699882] CSV file data columns correspond to selected fields of the of NonLinLoc Hypocenter format output http://alomax.free.fr/nlloc/soft7.00/formats.html#_location_hypphs_ Plots show: Subset of NLL-SSST-coherence earthquake relocations 2023.01.01 to 2023-03-24 with ellipsoid semi-major axis (NLL EllipsoidLen3) ≤ 10km (13,653 events). Symbol size is proportional to event magnitude. Used AFAD stations shown by light gray inverted pyramids. KOERI stations shown by dark gray inverted pyramids. Origin-time plot event colors: Blue: before 2023-02-06 M 7.8 event Yellow: from 2023-02-06 01h17 UTC M 7.8 event through 2023-02-06 10h24 UTC M 7.6 event Orange to Red: after 2023-02-06 10h24 UTC M 7.6 event Plot data: Background image from https://opentopography.org/ (approximate projection). Mapped surface faults (light purple) from: Emre, Ö., Duman, T.Y., Özalp, S., Şaroğlu, F., Olgun, Ş., Elmacı, H. & Çan, T., 2018. Active fault database of Turkey. Bull Earthquake Eng, 16, 3229–3275. https://doi.org/10.1007/s10518-016-0041-2 Surface Rupture Lines (green) from USGS "Turkey Earthquake Emergency Response" map: https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=5229bb842bd64b688d769abbefe43b46 Thanks to Sinan Ozeren, Didem Cambaz, Fatih Turhan, Onur Tan, Alberto Michelini and Pierre Henry for assistance and discussions.

DATA AND RESOURCES: Earthquake relocations performed using seismic phase arrival picks and station metadata available from: Republic of Turkey, Ministry of Interior, Disaster and Emergency Management Presidency, Earthquake Department (AFAD) https://deprem.afad.gov.tr/event-catalog. NLL-SSST-coherence earthquake relocations done with NonLinLoc (http://www.alomax.net/nlloc, https://github.com/alomax/NonLinLoc) configured for NLL-SSST-coherence (https://doi.org/10.5281/zenodo.4756709, Lomax and Savvaidis, 2022). SeismicityViewer (http:// www.alomax.net/software) was used for 3D seismicity analysis and plotting. Waveforms for the following channels and networks were obtained through the specified FDSN (https://www.fdsn.org/) data centers: KO_DARE_--_HHZ,KO_SARI_--_HHZ,KO_SVRC_--_HHZ,KO_KMRS_--_HHZ,KO_URFA_--_HHZ,KO_KHMN_--_HNZ,KO_GAZ_--_HHZ,KO_CEYT_--_HHZ,KO_KRTS_--_HNZ,KO_TAHT_--_HHZ : https://doi.org/10.7914/SN/KO https://eida.koeri.boun.edu.tr ; TU_ANDN_--_HHZ : https://doi.org/10.7914/SN/TU http://www.orfeus-eu.org ; GE_ARPR_--_SHZ,GE_ARPR_--_BHZ : https://doi.org/10.14470/TR560404 https://geofon.gfz-potsdam.de ; KO_GAZ_--_HHZ,KO_BNN_--_HHZ : https://doi.org/10.7914/SN/KO http://service.iris.edu ; The facilities of IRIS Data Services, and specifically the IRIS Data Management Center, were used for access to waveforms and related metadata used in this study. IRIS Data Services are funded through the Seismological Facilities for the Advancement of Geoscience and EarthScope (SAGE) Proposal of the National Science Foundation under Cooperative Agreement EAR-1261681.

{"references": ["Lomax, A. and Savvaidis, A. (2022) 'High-Precision Earthquake Location Using Source-Specific Station Terms and Inter-Event Waveform Similarity', Journal of Geophysical Research: Solid Earth, 127(1), p. e2021JB023190. Available at: https://doi.org/10.1029/2021JB023190.", "Lomax, A. (2020) 'The 2020 Mw 6.5 Monte Cristo Range, Nevada earthquake: relocated seismicity shows rupture of a complete shear-crack system'. Available at: https://doi.org/10.31223/X5X015."]}