气候变化领域集成服务门户(CCPortal): Seismic amplitude tomography for crustal attenuation beneath China

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DOI	10.1111/j.1365-246X.2008.03776.x
	Seismic amplitude tomography for crustal attenuation beneath China
	Hearn, Thomas M.; Wang, Suyun; Pei, Shunping; Xu, Zhonghuai; Ni, James F.; Yu, Yanxiang
通讯作者	Hearn, TM (通讯作者)
发表日期	2008
ISSN	0956-540X
EISSN	1365-246X
起始页码	223
结束页码	234
卷号	174 期号:1
英文摘要	Amplitude tomography reconstructs seismic attenuation directly from recorded wave amplitudes. We have applied the tomography to amplitude data reported in the 'Annual Bulletin of Chinese Earthquakes' and interpreted the regionally varying crustal attenuation in terms of tectonics. The seismic amplitudes were originally recorded for determining the M-L and M-S magnitudes. They generally correspond to the maximum amplitudes of the horizontal components of the short-period S waves and intermediate-period Rayleigh waves. Both sets of measurements are sensitive to crustal structure. The peak amplitudes from M-L amplitudes spread spherically with significant dispersion and scattering. M-S amplitudes show cylindrical spreading with little dispersion. Average crustal Q values for attenuation at 1 Hz are 737 and 505 for M-L and M-S, respectively, with substantial regional variations. Frequency dependence in the attenuation is also indicated. Regions with the lowest attenuation (high Q values) are beneath the south China Block, Sichuan Basin, Ordos Platform, the Daxinganling and the Korea Craton. These tend to be tectonically inactive regions, which are generally dominated by intrusive and cratonic rocks in the upper crust. Regions with the highest attenuation (low Q values) are beneath Bohai Basin, Yunnan, eastern Songpan-Ganzi Terrain, margins of the Ordos platform and the Qilian Shan. These are predominantly active basins, grabens and fold belts. The continental margin also highly attenuates both S and surface waves.
关键词	LG CODA ATTENUATION HIGH-PRESSURE ROCKS VELOCITY STRUCTURE WAVE-PROPAGATION QUALITY FACTOR UPPER-MANTLE NORTH CHINA EVOLUTION EXHUMATION TECTONICS
英文关键词	seismic attenuation; seismic tomography; crustal structure; Asia
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000256615300017
来源期刊	GEOPHYSICAL JOURNAL INTERNATIONAL
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/257575
推荐引用方式 GB/T 7714	Hearn, Thomas M.,Wang, Suyun,Pei, Shunping,et al. Seismic amplitude tomography for crustal attenuation beneath China[J]. 中国科学院青藏高原研究所,2008,174(1).
APA	Hearn, Thomas M.,Wang, Suyun,Pei, Shunping,Xu, Zhonghuai,Ni, James F.,&Yu, Yanxiang.(2008).Seismic amplitude tomography for crustal attenuation beneath China.GEOPHYSICAL JOURNAL INTERNATIONAL,174(1).
MLA	Hearn, Thomas M.,et al."Seismic amplitude tomography for crustal attenuation beneath China".GEOPHYSICAL JOURNAL INTERNATIONAL 174.1(2008).