气候变化领域集成服务门户(CCPortal): Seismic detection of the X-discontinuity beneath the Ryukyu subduction zone from the SdP conversion phase

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DOI	10.26464/epp2018020
	Seismic detection of the X-discontinuity beneath the Ryukyu subduction zone from the SdP conversion phase
	Cui, QingHui; Li, WenLan; Li, GuoHui; Ma, MaiNing; Guan, XiaoYu; Zhou, YuanZe
通讯作者	Cui, QH ; Zhou, YZ (通讯作者)
发表日期	2018
ISSN	2096-3955
起始页码	208
结束页码	219
卷号	2 期号:3
英文摘要	The X-discontinuity, which appears at the depth of approximately 300 km, is an important seismic interface with positive velocity contrasts in the upper mantle. Detecting its presence and topography can be useful to understand phase transformations of relevant mantle minerals under the high-temperature and high-pressure circumstance of the Earth's interior. In this study, we detect the X-discontinuity beneath the Ryukyu subduction zone using five intermediate-depth events recorded by the dense Alaska Regional Network (AK). The X-discontinuity is successfully revealed from the robust slant stacking of the secondary down-going and converting SdP phases. From the depth distribution of conversion points, we find that the X-discontinuity's depth ranges between 269 km and 313 km, with an average depth of 295 km. All the conversion points are located beneath the down-dipping side of the Philippine Sea slab. From energy comparisons in vespagrams for observed and synthetic seismograms, the strong converted energy is more likely from a thin high-velocity layer, and the S-wave velocity jumps across the X-discontinuity are up to 5% to 8% with an average of 6.0%. According to previous petrological and seismological studies, the X-discontinuity we detected can be interpreted as the phase transformation of coesite to stishovite in eclogitic materials within the oceanic crust.
关键词	UPPER-MANTLE DISCONTINUITIES PHILIPPINE SEA PLATE WAVE-FORM DATA TONGA TRANSITION PRECURSORS SHARPNESS PRESSURE ECLOGITE MOTION
英文关键词	Ryukyu subduction zone; X-discontinuity; coesite-stishovite transformation; dense network; SdP conversion phase
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000448277400003
来源期刊	EARTH AND PLANETARY PHYSICS
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/259121
推荐引用方式 GB/T 7714	Cui, QingHui,Li, WenLan,Li, GuoHui,et al. Seismic detection of the X-discontinuity beneath the Ryukyu subduction zone from the SdP conversion phase[J]. 中国科学院青藏高原研究所,2018,2(3).
APA	Cui, QingHui,Li, WenLan,Li, GuoHui,Ma, MaiNing,Guan, XiaoYu,&Zhou, YuanZe.(2018).Seismic detection of the X-discontinuity beneath the Ryukyu subduction zone from the SdP conversion phase.EARTH AND PLANETARY PHYSICS,2(3).
MLA	Cui, QingHui,et al."Seismic detection of the X-discontinuity beneath the Ryukyu subduction zone from the SdP conversion phase".EARTH AND PLANETARY PHYSICS 2.3(2018).