Acoustic detection of the causative fault of 1969 M(s)7.4 earthquake in Bohai Sea

doi:10.3969/j.issn.0001-5733.2009.09.013

	Acoustic detection of the causative fault of 1969 M(s)7.4 earthquake in Bohai Sea
	Li Xi-Shuang 1,2; Pei Yan-Liang 1,2; Liu Bao-Hua 1,2; Zhao Yue-Xia 1,2; Liu Chen-Guang 1,2; Xie Qiu-Hong 1,2,3; Hua Qing-Feng 1,2; Deng Sheng-Gui 3
刊名	CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
	2009-09
卷号	52 期号:9 页码:2291-2301
关键词	M(s)7.4 earthquake in Bohai Sea in 1969 Causative fault Acoustic detecting
ISSN号	0001-5733
DOI	10.3969/j.issn.0001-5733.2009.09.013
英文摘要	The M(s)7.4 earthquake occurred on 18 July 1969 was the only strong earthquake that has been recorded by seismometers in Bohai Sea. Now arguments about this large earthquake are focused on its causative fault. In 2005 similar to 2008, we finished three cruises in the epicenter region and collected several hundreds high-resolution acoustic surveying data, including shallow penetrated single channel data, sidescan sonar data and CHIRP data. This paper reports study results of these new acoustic data. A micro depression belt is newly found in Holocene sediments 2 similar to 3 m beneath seabed in the epicenter region and it strikes NE30 degrees, is 20 km long and 3 km wide. CHIRP data reveal that depositional interface formed at 5000 a B. P. has a 1.5 m vertical offset in the belt. The depression belt, BZ28 fault and aftershocks distribution of 1969 earthquake coincide in position, so it can be assumed that the depression belt is formed by BZ28 fault and the deformation of the bottom of seismic sequence A is caused by 1969 earthquake. BZ28 fault is the causative fault of this large earthquake and it is a sub-fault in the Tan-Lu Fault Zone and strikes NE30 degrees. Shallow penetrated single channel seismic data show that it is active during the late Holocene. According to sediments age and vertical offset, we calculate the vertical slip rate of BZ28 fault since late Pleistocene. The result shows that activity intensity of BZ28 fault has the trend of increasing from 0.05 mm/a since the late Pleistocene to 0.3 mm/a during the Holocene.
WOS研究方向	Geochemistry & Geophysics
语种	中文
出版者	SCIENCE PRESS
WOS记录号	WOS:000270377100013
内容类型	期刊论文
源URL	[http://ir.fio.com.cn:8080/handle/2SI8HI0U/26726]
专题	自然资源部第一海洋研究所
通讯作者	Li Xi-Shuang
作者单位	1.FIO, Key Lab Marine Sedimentol & Environm Geol, Qingdao 266061, Peoples R China 2.SOA, Inst Oceanog 1, Qingdao 266061, Peoples R China 3.Ocean Univ China, Earth Sci Coll, Qingdao 266003, Peoples R China
推荐引用方式 GB/T 7714	Li Xi-Shuang,Pei Yan-Liang,Liu Bao-Hua,et al. Acoustic detection of the causative fault of 1969 M(s)7.4 earthquake in Bohai Sea[J]. CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,2009,52(9):2291-2301.
APA	Li Xi-Shuang.,Pei Yan-Liang.,Liu Bao-Hua.,Zhao Yue-Xia.,Liu Chen-Guang.,...&Deng Sheng-Gui.(2009).Acoustic detection of the causative fault of 1969 M(s)7.4 earthquake in Bohai Sea.CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,52(9),2291-2301.
MLA	Li Xi-Shuang,et al."Acoustic detection of the causative fault of 1969 M(s)7.4 earthquake in Bohai Sea".CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 52.9(2009):2291-2301.