Research Article

Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ)

Volume: 15 Number: 3 September 30, 2026

Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ)

Abstract

This study characterizes seismicity and stress regime in the westernmost part of the North Anatolian Fault Zone (NAFZ), focusing on the Saros segment, where dextral strike-slip deformation transitions into the transtensional northern Aegean domain. Unlike previous regional studies that combine Marmara and broader Aegean datasets or focus on individual rupture sequences, this study isolates a coordinate-bounded transition window to quantify the intrinsic seismic behavior of the terminal NAFZ–North Aegean Trough (NAT) linkage zone within a completeness-controlled framework. A December 1917–September 2025 earthquake catalog was compiled and homogenized to local magnitude (ML). Completeness analysis yields a reference Mc ≈ 3.2, consistent with Gutenberg–Richter statistics. Recurrence and annual probability metrics were evaluated for 1917–2025, 1985–2025, and 2010–2025 to assess temporal stability and completeness-related effects in seismic productivity. Recurrence and frequency–magnitude characteristics of the non-declustered and declustered catalogs were compared to assess aftershock effects on seismic rates. For events with M ≥ Mc, the estimated parameters are b = 0.91 ± 0.05 and a = 5.392 indicate moderate seismic productivity. Focal mechanisms and stress tensor inversion indicate a dominant dextral strike-slip regime with subordinate N–S extension, confirming a transtensional stress field linking the Saros region to the northern Aegean. Integrated completeness-controlled seismicity statistics and stress-tensor inversion show that the Saros segment functions as a transform–transtensional linkage corridor rather than a discrete tectonic boundary, refining the seismotectonic framework of the Marmara–Saros–North Aegean transition zone and providing robust parameters for seismic hazard and fault-segmentation analyses.

Keywords

Supporting Institution

No funding was received for this study.

Ethical Statement

Ethical Statement: This study is based on earthquake catalog and/or publicly available seismic data and does not involve human participants, animals, or personal data. Therefore, ethical committee approval and informed consent are not applicable.

Thanks

The author thanks the editors and the reviewers for their valuable discussions, which contributed to the development of this study.

References

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Details

Primary Language

English

Subjects

Seismology

Journal Section

Research Article

Publication Date

September 30, 2026

Submission Date

January 22, 2026

Acceptance Date

March 25, 2026

Published in Issue

Year 2026 Volume: 15 Number: 3

APA
Tamtaş, B. D. (2026). Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ). Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, 15(3), 1159-1182. https://doi.org/10.17798/bitlisfen.1869499
AMA
1.Tamtaş BD. Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ). Bitlis Eren Üniversitesi Fen Bilimleri Dergisi. 2026;15(3):1159-1182. doi:10.17798/bitlisfen.1869499
Chicago
Tamtaş, Burçin Didem. 2026. “Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ)”. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi 15 (3): 1159-82. https://doi.org/10.17798/bitlisfen.1869499.
EndNote
Tamtaş BD (September 1, 2026) Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ). Bitlis Eren Üniversitesi Fen Bilimleri Dergisi 15 3 1159–1182.
IEEE
[1]B. D. Tamtaş, “Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ)”, Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, vol. 15, no. 3, pp. 1159–1182, Sept. 2026, doi: 10.17798/bitlisfen.1869499.
ISNAD
Tamtaş, Burçin Didem. “Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ)”. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi 15/3 (September 1, 2026): 1159-1182. https://doi.org/10.17798/bitlisfen.1869499.
JAMA
1.Tamtaş BD. Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ). Bitlis Eren Üniversitesi Fen Bilimleri Dergisi. 2026;15:1159–1182.
MLA
Tamtaş, Burçin Didem. “Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ)”. Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, vol. 15, no. 3, Sept. 2026, pp. 1159-82, doi:10.17798/bitlisfen.1869499.
Vancouver
1.Burçin Didem Tamtaş. Seismicity Parameters of the Westernmost Part of the North Anatolian Fault Zone (NAFZ). Bitlis Eren Üniversitesi Fen Bilimleri Dergisi. 2026 Sep. 1;15(3):1159-82. doi:10.17798/bitlisfen.1869499

Bitlis Eren University

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Bitlis Eren University Graduate Institute

Bes Minare Mah. Ahmet Eren Bulvari, Merkez Kampus, 13000 BITLIS

E-mail: fbe@beu.edu.tr