气候变化领域集成服务门户(CCPortal): Fault geometry beneath the western and Central Marmara Sea, Turkey, based on ocean bottom seismographic observations: Implications for future large earthquakes

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DOI	10.1016/j.tecto.2020.228568
	Fault geometry beneath the western and Central Marmara Sea, Turkey, based on ocean bottom seismographic observations: Implications for future large earthquakes
	Yamamoto Y.; Kalafat D.; Pinar A.; Takahashi N.; Coskun Z.; Polat R.; Kaneda Y.; Ozener H.
发表日期	2020
ISSN	00401951
卷号	791
英文摘要	Beneath the Marmara Sea, Turkey, the Main Marmara Fault (MMF), the offshore part of the North Anatolian Fault (NAF), is a well-known seismic gap for future M > 7 earthquakes. However, its detailed fault geometry and microearthquake activity have been debated for several decades. Using data acquired from long-term ocean bottom seismograph (OBS) observations, we made precise hypocenter estimations based on 3-D Vp and Vs velocity structures and assessed the fault geometry beneath the western and central parts of the MMF. The results indicate a segmentation boundary between the near-vertical western part and the south-dipping eastern part located around 28.10°E. Enriched OBS locations indicate microseismicity along both the inner and outer boundary faults of the Central Basin, especially on the western side. A comparison with previously published results suggests that the seismicity pattern has not changed for at least two years, between 2014 and 2016. Using a combined dataset of this and previous studies, lateral variations in the dip angle along the MMF fault segment from 27.4°E to 28.8°E were investigated. Based on this, we depicted on-fault seismicity along the MMF and defined three inactive areas of microseismicity. Two are located in the western segment, corresponding to the rupture area of the 1912 Ms. 7.4 earthquake, and the other, the largest, is located on the eastern segment. From a comparison of previous seismic and geodetic studies, it is considered that this area is a fully locked zone and has the potential for large earthquakes. Having compared the difference between hypocenter locations determined from OBSs and land-based stations, it is proposed that the epicentral locations of the mainshock and aftershocks of the September 26, 2019, M 5.7 earthquake are located much closer to the MMF than locations reported from only land-based results. © 2020 Elsevier B.V.
关键词	Fault geometry Main Marmara Fault Ocean bottom seismographic observation Seismicity
英文关键词	Earthquake effects; Geometry; Location; Offshore oil well production; Seismic waves; Hypocenter location; Implications for futures; Lateral variations; Marmara sea , Turkey; Microearthquake activities; North Anatolian Fault; Ocean bottom seismographs; Segmentation boundaries; Faulting; aftershock; earthquake hypocenter; earthquake magnitude; earthquake mechanism; earthquake recurrence; fault geometry; fault zone; future prospect; microearthquake; ocean bottom seismometer; seismicity; tectonic setting; Sea of Marmara; Turkey
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207901
作者单位	Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa 2360001, Japan; Kandilli Observatory and Earthquake Research Institute, Bogazici University, Cengelkoy-Istanbul, 34686, Turkey; Institute of Education, Research and Regional Cooperation for Crisis Management Shikoku, Kagawa University, 2217-20, Hayashi-cho, Takamatsu, 7610396, Japan
推荐引用方式 GB/T 7714	Yamamoto Y.,Kalafat D.,Pinar A.,et al. Fault geometry beneath the western and Central Marmara Sea, Turkey, based on ocean bottom seismographic observations: Implications for future large earthquakes[J],2020,791.
APA	Yamamoto Y..,Kalafat D..,Pinar A..,Takahashi N..,Coskun Z..,...&Ozener H..(2020).Fault geometry beneath the western and Central Marmara Sea, Turkey, based on ocean bottom seismographic observations: Implications for future large earthquakes.Tectonophysics,791.
MLA	Yamamoto Y.,et al."Fault geometry beneath the western and Central Marmara Sea, Turkey, based on ocean bottom seismographic observations: Implications for future large earthquakes".Tectonophysics 791(2020).