Evolution of fold-thrust belts and Cenozoic uplifting of the South Tianshan Mountain range in the Kuqa region, Northwest China. (March 2017)

• Record Type: Journal Article
• Authors: Wen, Lei; Li, Yue-Jun; Zhang, Guang-Ya; Tian, Zuo-Ji; Peng, Geng-Xin; Qiu, Bin; Huang, Zhi-Bin; Luo, Jun-Cheng; Zhang, Qiang
• Is Part Of: Journal of Asian earth sciences. Volume 135(2017)
• Page Start: 327
• Page End: 337
• Publication Date: 2017-03
• Subjects: South Tianshan Mountain range -- Tectonic uplifting amount -- Kuqa fold-thrust belt -- Critical Taper Wedge Mechanics -- Cenozoic; Earth sciences -- Asia -- Periodicals; Sciences de la terre -- Asie -- Périodiques; Earth sciences; Asia; Periodicals; 555.05
• DOI: 10.1016/j.jseaes.2017.01.002
• Languages: English
• ISSNs: 1367-9120

Abstract

Graphical abstract: Highlights: We deduce a formula between orogen tectonic uplifting and FTB extending distance. The South Tianshan uplifts 4.1 km in the middle segment of Kuqa during 6~3 Ma. The South Tianshan uplifts 4.7 to 5.0 km in Kuqa during 3~0 Ma. Abstract: The evolution of the Kuqa fold-thrust belt is accompanied with the Cenozoic uplifting of South Tianshan Mountain range. The critical Coubomb wedge theory can be well applied to the structural evolution of the Kuqa fold-thrust belt where the décollement structures are well developed. Following the initial hypotheses of this theory, with the base of the taper wedge (not the sea level) as the reference level, we propose a geometric relationship between the evolution of fold-thrust belt and tectonic uplifting of orogen, and deduce a calculation formula between orogen tectonic uplifting amount (very different from the topographic uplifting) (∂H), fold-thrust belt extending distance (∂S) and crustal shortening amount (∂L): ∂H = (∂S − ∂L) ∗ tan(α + ∂α) + [tan(α + ∂α)/tanα − 1] ∗ H0 . In this paper we select two representative seismic profiles across the Kuqa fold-thrust belt to reconstruct the structural evolution, and use the calculation formula to get the uplifting amount of the South Tianshan Mountain range in Kuqa region during two geological periods. The results showed: during the end of Miocene to the end of Pliocene, the uplifting amount of the South Tianshan Mountain range in the middle segment of Kuqa (∂HM1 ) is 4.1 km; during the end of Pliocene to the present, the uplifting amount of the South Tianshan Mountain range in the middle segment of Kuqa (∂HM2 ) is 4.7 km, and in the east segment of Kuqa (∂HE ) is 5.0 km.