气候变化领域集成服务门户(CCPortal): Shortening Rates and Recurrence of Large Earthquakes From Folded and Uplifted Terraces in the Western Danghe Nan Shan Foreland, North Tibet

CCPortal

DOI	10.1029/2021JB023736
	Shortening Rates and Recurrence of Large Earthquakes From Folded and Uplifted Terraces in the Western Danghe Nan Shan Foreland, North Tibet
	Shao, Yanxiu; van der Woerd, Jerome; Liu-Zeng, Jing; Yuan, Daoyang; Yao, Yunsheng; Zou, Xiaobo; Wang, Pengtao
发表日期	2023
ISSN	2169-9313
EISSN	2169-9356
卷号	128 期号:1
英文摘要	Understanding the three-dimensional structure, segmentation, and kinematics of complex fault systems is essential to assessing the size of potential earthquakes and related seismic hazards. The Danghe Nan Shan thrust, a major splay of the Altyn Tagh fault (ATF) in north Tibet, is one of these complex fault junctions. Near the town of Subei, the western Danghe Nan Shan thrust composes two left-stepping faults outlined by fault scarps in front of folded and uplifted alluvial fans and terraces. Age constraints and 2D reconstructions of the accumulated slip above a transient base level of four terraces standing 7-60 m above the present stream bed yield shortening and vertical uplift rates of 0.5 +/- 0.1 and 1.1 +/- 0.3 mm/yr, respectively, over the last 130 ka on the southern thrust. Along the northern thrust, vertical terrace offsets of 1.5-3.6 m and horizontal slip of 4.5 m documented in a paleoseismological trench occurred after 12 +/- 4 ka, constraining coeval rates of 0.3 +/- 0.1 mm/yr for uplift and shortening. Overall, 1.4 +/- 0.4 mm/yr terrace uplift and 0.8 +/- 0.2 mm/yr shortening rates are determined, in agreement with late Miocene long-term exhumation rate estimates. Our fault mapping and geomorphic and structural observations imply that the western Danghe Nan Shan thrust accommodates slip transfer from the ATF to the west to thrusting and shortening farther east in the Qilian Shan region. Considering the scarp sizes, their lateral extent, the geometry of the faults at depth, and their slip-rate, we suggest the possible occurrence of Mw 7+ earthquakes near Subei. Plain Language Summary How faults slip is essential to understanding continental deformation and seismic hazards. In the western Qilian Shan region, the Danghe Nan Shan is one of the largest ranges bounded by active thrust faults. West and south of Subei, these thrusts can be followed for several kilometers along meter-high scarps and folded terraces. Quantifying the cumulative deformation of the folded and uplifted terraces and fans enables to constrain shortening rates of about 1 mm/yr over the last 130 ka. Evidence from surface geomorphology and sub-surface trenching across the faults indicates the occurrence of large magnitude potentially up to Mw 7 seismic events in the last 16 ka. Integrating age-controlled cumulative geological observations with field-documented co-seismic deformation increases the knowledge of slip rate and co-seismic displacement for seismic hazards.
英文关键词	ALTYN-TAGH FAULT; APATITE FISSION-TRACK; CONSTANT SLIP RATE; QILIAN-SHAN; LATE QUATERNARY; FLUVIAL TERRACES; M-W; TECTONIC EVOLUTION; HEXI CORRIDOR; KUNLUN FAULT
WOS研究方向	Geochemistry & Geophysics
WOS记录号	WOS:000943261000001
来源期刊	JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283361
作者单位	Tianjin University; Universites de Strasbourg Etablissements Associes; Universite de Strasbourg; Centre National de la Recherche Scientifique (CNRS); Lanzhou University; China Earthquake Administration
推荐引用方式 GB/T 7714	Shao, Yanxiu,van der Woerd, Jerome,Liu-Zeng, Jing,et al. Shortening Rates and Recurrence of Large Earthquakes From Folded and Uplifted Terraces in the Western Danghe Nan Shan Foreland, North Tibet[J],2023,128(1).
APA	Shao, Yanxiu.,van der Woerd, Jerome.,Liu-Zeng, Jing.,Yuan, Daoyang.,Yao, Yunsheng.,...&Wang, Pengtao.(2023).Shortening Rates and Recurrence of Large Earthquakes From Folded and Uplifted Terraces in the Western Danghe Nan Shan Foreland, North Tibet.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,128(1).
MLA	Shao, Yanxiu,et al."Shortening Rates and Recurrence of Large Earthquakes From Folded and Uplifted Terraces in the Western Danghe Nan Shan Foreland, North Tibet".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 128.1(2023).