气候变化领域集成服务门户(CCPortal): Late Miocene topographic inversion in southwest Tibet based on integrated paleoelevation reconstructions and structural history

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DOI	10.1016/j.epsl.2009.01.006
	Late Miocene topographic inversion in southwest Tibet based on integrated paleoelevation reconstructions and structural history
	Murphy, Michael A.; Saylor, Joel E.; Ding, Lin
通讯作者	Murphy, MA (通讯作者)
发表日期	2009
ISSN	0012-821X
起始页码	1
结束页码	9
卷号	282 期号:1-4
英文摘要	Investigations of the deformation history of the Himalayan orogen support interpretations of rapid and striking changes in the landscape of the Tibetan Himalaya and High Himalaya. We examine this issue by integrating oxygen isotope-based paleoelevation reconstructions of the Zada basin in southwestern Tibet with information on the structural evolution of the High and Tibetan Himalaya between 79 degrees E and 84 degrees 30'E. delta(18)O(psw) values were calculated from delta(18)O(cc) values from pristine fluvial Miocene gastropod shells. Analyses comparing the most negative delta(18)O(sw) and reconstructed delta(18)O(psw) values to Delta delta(18)O(sw) versus elevation relationships based on both thermodynamic models and an empirical data set suggest a decrease in the mean watershed elevation of 1 to 1.5 km since the Late Miocene. Geologic mapping and structural data from crustal scale fault systems in the Zada region and regions to its east indicate a phase of arc-normal shortening and vertical thickening since the Middle Miocene, followed by ongoing arc-parallel extension and vertical thinning. These results suggest that regions in this part of the orogen transitioned from undergoing arc-normal shortening to arc-parallel extension in the Late Miocene, and that arc-parallel extensional structures root deeply within the Himalayan thrust wedge. When combined with data on the distribution, age, and provenance of sedimentary basins, our geologic mapping, structural data, and paleoelevation results suggest that this transition from shortening to extension was accompanied by a topographic inversion from mountains to basins in <4 m.y. These observations can be explained by a foreland propagating fault system that accommodates outward radial expansion of the Himalayan orogen. (C) 2009 Elsevier B.V. All rights reserved.
关键词	FOLD-THRUST BELT ISOTOPE-BASED PALEOALTIMETRY KARAKORAM FAULT SYSTEM INDIA-ASIA COLLISION SOUTHERN TIBET CONTINENTAL SUBDUCTION WESTERN NEPAL HIMALAYAN ARC SUTURE ZONE TECTONIC IMPLICATIONS
英文关键词	Himalaya; syncollisional extension; oxygen isotopes; paleoelevation
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000266899800001
来源期刊	EARTH AND PLANETARY SCIENCE LETTERS
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/257698
推荐引用方式 GB/T 7714	Murphy, Michael A.,Saylor, Joel E.,Ding, Lin. Late Miocene topographic inversion in southwest Tibet based on integrated paleoelevation reconstructions and structural history[J]. 中国科学院青藏高原研究所,2009,282(1-4).
APA	Murphy, Michael A.,Saylor, Joel E.,&Ding, Lin.(2009).Late Miocene topographic inversion in southwest Tibet based on integrated paleoelevation reconstructions and structural history.EARTH AND PLANETARY SCIENCE LETTERS,282(1-4).
MLA	Murphy, Michael A.,et al."Late Miocene topographic inversion in southwest Tibet based on integrated paleoelevation reconstructions and structural history".EARTH AND PLANETARY SCIENCE LETTERS 282.1-4(2009).