气候变化领域集成服务门户(CCPortal): Development of contrasting folding styles in the western Yangtze block, South China: Insights from numerical modeling

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DOI	10.1016/j.tecto.2020.228579
	Development of contrasting folding styles in the western Yangtze block, South China: Insights from numerical modeling
	Huang G.; Zhang Z.; Zhang H.; Huangfu P.; Li Z.-H.
发表日期	2020
ISSN	00401951
卷号	792
英文摘要	Two contrasting folding styles are well developed along both sides of the Qiyueshan fault, South China. The western part is characterized by chevron anticlines and box synclines in the Eastern Sichuan domain, while the eastern part features typical chevron synclines and box anticlines in the western Hunan-Hubei domain. These contrasting structures are important in better understanding the intracontinental orogeny around the eastern Sichuan Basin. In this study, we conducted a series of 2-D numerical simulations using the finite difference method. The model results indicate that the key parameters include stratigraphic competence, number and distribution of intermediate weak layers, and thickness of basal weak layer. Among them, the thickness of basal weak layer plays the most important role in shaping the two distinct structural styles. In the models with thin basal weak layer (<1 km), high-quality chevron anticlines are developed with the presence of multiple intermediate weak layers. These folds are mainly characterized by fault-propagation folds or fault-bend folds. The basal weak layer corresponds to the relatively thin Cambrian evaporite layer in the Eastern Sichuan domain. In contrast, in the models with thick basal weak layer (>8 km), a series of coherent chevron synclines are developed, and mainly form décollement folds. These characteristics are similar to the structural styles revealed by seismic profiles in the western Hunan-Hubei domain. This weak layer may represent the accumulation of mechanically weak rocks (e.g., slate, schist and phyllite) in Neoproterozoic Lengjiaxi and Tieshajie Groups in the western Hunan-Hubei domain, which is also consistent with the geophysical observations (e.g., weak seismic reflection, high electrical conductivity, and Bouguer gravity low anomaly). Both the differential thickness of basal weak layer along the “flat-ramp-flat” décollement and the overlying multiple intermediate weak layers contribute to the formation of the contrasting folding styles around the eastern Sichuan Basin. © 2020 Elsevier B.V.
关键词	Chevron anticline Chevron syncline Fault-related fold Multiple décollements Numerical modeling
英文关键词	Numerical methods; Numerical models; Seismic waves; Seismology; Stratigraphy; 2-D numerical simulation; Bouguer gravity; Fault-propagation folds; Geophysical observations; High electrical conductivity; Seismic profiles; Seismic reflections; Structural styles; Finite difference method; anticline; computer simulation; decollement; finite difference method; folding; numerical model; orogeny; China; Sichuan Basin; Yangtze Platform
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207774
作者单位	Key Laboratory of Computational Geodynamics, University of Chinese Academy of Sciences, Beijing, 100049, China; Beijing PST Service Corporation, Beijing, 100049, China; Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
推荐引用方式 GB/T 7714	Huang G.,Zhang Z.,Zhang H.,et al. Development of contrasting folding styles in the western Yangtze block, South China: Insights from numerical modeling[J],2020,792.
APA	Huang G.,Zhang Z.,Zhang H.,Huangfu P.,&Li Z.-H..(2020).Development of contrasting folding styles in the western Yangtze block, South China: Insights from numerical modeling.Tectonophysics,792.
MLA	Huang G.,et al."Development of contrasting folding styles in the western Yangtze block, South China: Insights from numerical modeling".Tectonophysics 792(2020).