气候变化领域集成服务门户(CCPortal): The crust and upper mantle discontinuity structure beneath Alaska inferred from receiver functions

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DOI	10.1016/j.pepi.2004.12.002
	The crust and upper mantle discontinuity structure beneath Alaska inferred from receiver functions
	Ai, YH; Zhao, DP; Gao, X; Xu, WW
发表日期	2005
ISSN	0031-9201
EISSN	1872-7395
起始页码	339
结束页码	350
卷号	150 期号:4
英文摘要	In this study, three receiver function stacking methods are used to study the detailed crust and upper mantle structure beneath south-central Alaska. We used teleseismic waveform data recorded by 36 stations in the Broadband Experiment Across the Alaska Range (BEAAR) and 4 permanent stations in Alaska. H-kappa stacking method using P-to-S converted wave and its multiply reflected waves between the Earth's surface and the Moho discontinuity is adopted to estimate the crustal thickness (H) and average crustal V-P/V-S ratio (K) in this region. The receiver function results for 24 stations show that the crustal thickness under Alaska ranges from 26.0 to 42.6 km with an average value of 33.8 km, and the V-P/V-S ratio varies from 1.66 to 1.94 with an average value of 1.81 which corresponds to an average Poisson's ratio of 0.277 with a range from 0.216 to 0.320. High Poisson's ratios under some stations are possibly caused by partial melting in the crust and the uppermost mantle. Common converted point (CCP) stacking results of receiver functions along three lines show clear Moho and slab images under this subduction zone. The depths of the slab from our CCP stacking images are consistent with those estimated from the Wadati-Benioff Zone (WBZ). In the area between two stations DH2 (147.8 degrees W, 63.3 degrees N) and DH3 (147.1 degrees W, 63.0 degrees N), a Moho depth offset of about 10 km is found by both the H-kappa and CCP stacking techniques. Common depth point (CDP) stacking of receiver functions shows not only the 410, 520- and 660-km discontinuities, but also significant variations (-30 to 15 km) in the transition zone thickness under the southwest and southeast parts of the study region. The transition zone becomes thinner by 20-30 km, indicating that the temperature there is 150-200 K higher than that of the normal mantle. (c) 2004 Elsevier B.V. All rights reserved.
关键词	TRANSITION ZONE BENEATH SAN-ANDREAS FAULT SOUTHERN CALIFORNIA SEISMIC EVIDENCE EARTHQUAKE IMAGES WAVES TIBET RATIO
英文关键词	receiver functions; crustal thickness; Poisson's ratio; the upper mantle discontinuities; Alaska
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000229418900006
来源期刊	PHYSICS OF THE EARTH AND PLANETARY INTERIORS
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/257375
推荐引用方式 GB/T 7714	Ai, YH,Zhao, DP,Gao, X,et al. The crust and upper mantle discontinuity structure beneath Alaska inferred from receiver functions[J]. 中国科学院青藏高原研究所,2005,150(4).
APA	Ai, YH,Zhao, DP,Gao, X,&Xu, WW.(2005).The crust and upper mantle discontinuity structure beneath Alaska inferred from receiver functions.PHYSICS OF THE EARTH AND PLANETARY INTERIORS,150(4).
MLA	Ai, YH,et al."The crust and upper mantle discontinuity structure beneath Alaska inferred from receiver functions".PHYSICS OF THE EARTH AND PLANETARY INTERIORS 150.4(2005).