Block-like versus distributed crustal deformation around the   northeastern Tibetan plateau

doi:10.1016/j.jseaes.2017.02.040

CORC > 北京大学 > 地球与空间科学学院

	Block-like versus distributed crustal deformation around the northeastern Tibetan plateau
	Wang, Yanzhao ; Wang, Min ; Shen, Zheng-Kang
刊名	JOURNAL OF ASIAN EARTH SCIENCES
	2017
关键词	GPS Northeastern Tibetan plateau Crustal deformation Deformable-block-motion model Seismic moment rate POSITIONING SYSTEM MEASUREMENTS UPPER-MANTLE BENEATH WESTERN HAIYUAN FAULT LEFT-SLIP RATE KUNLUN FAULT CONTINENTAL COLLISION ACTIVE DEFORMATION SOUTHERN CALIFORNIA STRAIN ACCUMULATION VELOCITY STRUCTURE
DOI	10.1016/j.jseaes.2017.02.040
英文摘要	It has been debated for decades whether crustal deformation in and around the Tibetan plateau is distributed or block-like. We model crustal deformation in northeastern Tibet using a deformable-block-motion model, in which kinematic parameters of block motion and internal deformation and the associated boundary slip rates are inverted for using GPS velocity data. The F-test is used to screen out station velocity outliers, justify independence of neighboring blocks, and determine the significance of block internal strains through an iteration process. As a result, fifteen blocks are identified, with their boundary faults slipping at rates of 1-10 mm/a. Blocks located east and north of the plateau have large sizes (>10(4) km(2) in area) in general, with little internal deformation. Six blocks within the plateau, in contrast, are smaller in sizes, with internal strain rates on the order of 1-10 nanostrain/a. Five blocks sitting at the northeast borderland of the plateau have small block sizes but no significant internal deformation. Our results show sinistral slip rates of 4.3 +/- 1.6 and 4.6 +/- 1.8 mm/a across the western and eastern segments of the Haiyuan fault, and 10.8 +/- 2.3, 4.6 +/- 2.6, and 3.8 +/- 2.1 mm/a across the western, central, and eastern segments of the East Kunlun fault, respectively. The southwestern, central, and northeastern segments of the Longmenshan fault slip right-laterally at rates of 1.7 +/- 1.1, 1.1 +/- 0.8, and 1.1 +/- 0.8 mm/a, with shortening rates of 1.1 +/- 1.2, 0.4 +/- 0.8, and 0.8 +/- 1.1 mm/a, respectively. We also develop a scheme to convert geodetic strain rate into seismic moment accumulation rate within blocks and at block boundaries, and estimate the two rates as,similar to 8.40 x 10(18) and similar to 2.06 x 10(19) N.m/a, respectively. In comparison, the corresponding seismic moment release rates are estimated as similar to 6.06 x 10(18) and similar to 2.44 x 10(19) N.m/a using an contemporary earthquake catalog of 1920-2015. Such results indicate that the seismic moment accumulation and release rates are comparable for the latest 95 years when the earthquake catalog is complete for strong to large events. Both geodetic and seismic estimates suggest that a major portion (similar to 70-80%) of the total seismic moment is accumulated and released at block boundaries, and a minor but still significant portion (similar to 20-30%) is accumulated and released within blocks. (C) 2017 The Author(s). Published by Elsevier Ltd.; National Natural Science Foundation of China [41474028, 41090294, 41104008]; China Earthquake Administration [200708002]; US National Science Foundation [EAR-1323052]; SCI(E); ARTICLE; 31-47; 140
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/472984]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Wang, Yanzhao,Wang, Min,Shen, Zheng-Kang. Block-like versus distributed crustal deformation around the northeastern Tibetan plateau[J]. JOURNAL OF ASIAN EARTH SCIENCES,2017.
APA	Wang, Yanzhao,Wang, Min,&Shen, Zheng-Kang.(2017).Block-like versus distributed crustal deformation around the northeastern Tibetan plateau.JOURNAL OF ASIAN EARTH SCIENCES.
MLA	Wang, Yanzhao,et al."Block-like versus distributed crustal deformation around the northeastern Tibetan plateau".JOURNAL OF ASIAN EARTH SCIENCES (2017).