Uplift of NW margin of Qaidam Basin in the Late Eocene: Implications for the initiation of Altyn Fault
-
摘要:
研究阿尔金断裂的演化是理解青藏高原隆升过程的重要环节。本文以柴达木盆地西北缘的地震剖面、残余厚度图、沉积相图等资料进行沉积、构造的综合研究,揭示了柴达木盆地西北缘在始新世晚期开始抬升,因此导致柴达木盆地西北缘生长地层的发育。这种抬升作用在平面上则表现为与阿尔金断裂呈~30°相交的NWW-SEE走向古隆起,以及与之相关的如冲积扇等边缘沉积相。本文分析认为阿尔金断裂在始新世晚期开始孕育,在深部形成左旋性质的韧性剪切带,在地表则通过形成左阶雁列式褶皱(即古隆起)来调节深部的位移量。
Abstract:The evolution of Altyn Fault holds a key link in understanding the formation process of Tibet Plateau. The sedimentary and tectonic study of seismic sections, strata isopach maps and sedimentary facies maps of NW Qaidam Basin reveals the initial uplifting related with Altyn Fault at the Late Eocene, which led to the formation of the growth strata at the NW margin of Qaidam Basin. While in the map view, these NWW-SEE trending uplift sintersect with Altyn Fault by an angle of ~30°and induce marginal sedimentary environment such as alluvial fan etc. Based on these observations, we conclude the initial development of Altyn Fault started at the Late Eocene, which may form a ductile sinistral shear zone in the deep and as a result a left-ordered echelon folding zone on the surface for accommodating the displacement.
-
Key words:
- Tibet Plateau /
- Qaidam /
- Altyn Fault /
- sinistral strike-slip
-
-
Chen WP, Chen CY and Belek J. 1999. Present-day deformation of the Qaidam basin with implications for intra-continental tectonics. Tectonophysics, 305(1-3): 165-181
Clark MK and Royden LH. 2000. Topographic ooze: Building the eastern margin of Tibet by lower crustal flow. Geology, 28(8): 703
Fang XM, Zhang WL, Meng QQ, Gao JP, Wang XM, King J, Song CH, Dai S and Miao YF. 2007. High-resolution magnetostratigraphy of the Neogene Huaitoutala section in the eastern Qaidam Basin on the NE Tibetan Plateau, Qinghai Province, China and its implication on tectonic uplift of the NE Tibetan Plateau. Earth and Planetary Science Letters, 258(1-2): 293-306
Jamison WR. 1991. Kinematics of compressional fold development in convergent wrench terrances. Tectonophysics, 190(2-4): 209-232
Li HB, Yang JS, Xu ZQ, Sun ZM, Tapponnier P, van der Woerd J and Meriaux AS. 2006. The constraint of the Altyn Tagh fault system to the growth and rise of the northern Tibetan plateau. Earth Science Frontiers, 13(4): 59-79 (in Chinese with English abstract)
Liu L, Chen DL, Wang C and Zhang CL. 2009. New progress on geochronology of high-pressure/ultrahigh-pressure metamorphic rocks from the South Altyn Tagh, the North Qaidam and the North Qinling orogenic, NW China and their geological significance. Journal of Northwest University (Natural Science Edition), 39(3): 472-479 (in Chinese with English abstract)
Meng QR and Fang X. 2008. Cenozoic tectonic development of the Qaidam Basin in the northeastern Tibetan Plateau. Geological Society of America Special Papers, 444: 1-24
Molnar P and Tapponnier P. 1975. Cenozoic tectonics of Asia: Effects of a continental collision. Science, 189(4201): 419-426
Ritts BD and Ulderico B. 2001. Mesozoic northeast Qaidam basin: Response to contractional reactivation of the Qilian Shan, and implications for the extent of Mesozoic intracontinental deformation in central Asia. Geological Society of America Bulletin, 194: 293-316
Sun ZM, Yang ZY, Pei JL, Ge XH, Wang XS, Yang TS, Li WM and Yuan SH. 2005. Magnetostratigraphy of Paleogene sediments from northern Qaidam Basin, China: Implications for tectonic uplift and block rotation in northern Tibetan Plateau. Earth and Planetary Science Letters, 237(3-4): 635-646
Tapponnier P, Xu ZQ, Roger F, Meyer B, Arnaud N, Wittlinger G and Yang JS. 2001. Oblique stepwise rise and growth of the Tibet Plateau. Science, 294(5547): 1671-1677
Tikoff B and Peterson K. 1998. Physical experiments of transpressional folding. Journal of Structural Geology, 20(6): 661-672
Titus SJ, Housen B and Tikoff B. 2007. A kinematic model for the Rinconada fault system in central California based on structural analysis of en echelon folds and paleomagnetism. Journal of Structural Geology, 29(6): 961-982
Wang J, Ni J and Liu P. 2007. Control of the early faulted depression of superimposed basins on uplift belts and depression belts: A new explanation for the origin of uplift belts and depression belts in the northern Qaidam Basin. Journal of Guilin University of Technology, 27(3): 299-303
Wang L, Xiao AC, Gong QL, Liu D, Shen ZY, Zhou SP, Wu L, Lou QQ and Sun XW. 2010. The unconformity in Miocene sequence of western Qaidam Basin and its tectonic significance. Scientia Sinica (Terrae), 40(11): 1582-1590 (in Chinese)
Wu L. 2011. The Cenozoic tectonic process of central segment of the Altyn Tagh Fault and its basin response. Ph. D. Dissertation. Hangzhou: Zhejiang University (in Chinese with English summary)
Wu L, Xiao AC, Wang LQ, Shen ZY, Zhou SP, Chen YZ, Wang L, Liu D and Guan JY. 2011. Late Jurassic-Early Cretaceous northern Qaidam Basin, NW China: Implications for the earliest Cretaceous intracontinental tectonism. Cretaceous Research, 32(4): 552-564
Wu L, Xiao AC, Wang LQ, Mao LG, Wang L, Dong YP and Xu B. 2012a. EW-trending uplifts along the southern side of the central segment of the Altyn Tagh Fault, NW China: Insight into the rising mechanism of the Altyn Mountain during the Cenozoic. Science China (Earth Sciences), 55(6): 926-939
Wu L, Xiao AC, Yang SF, Wang LQ, Mao LG, Wang L, Dong YP and Xu B. 2012b. Two-stage evolution of the Altyn Tagh Fault during the Cenozoic: New insight from provenance analysis of a geological section in NW Qaidam Basin, NW China. Terra Nova, 24(5): 387-395
Wu YZ, Li RS, Wang Z, Lei XW, Zhang Z and Xie CR. 2007. The attribution of Altyn marginal faults. Earth Science, 32(5): 662-670 (in Chinese with English abstract)
Xia WC, Zhang N, Yuan X, Fan LS and Zhang BS. 2001. Cenozoic Qaidam Basin, China: A stronger tectonic inversed, extensional rifted basin. AAPG Bulletin, 85(4): 715-736
Yang F, Ma Z, Xu T and Ye S. 1992. A Tertiary paleomagnetic stratigraphic profile in Qaidam basin. Acta Petrologica Sinica, 13(2): 97-101 (in Chinese with English abstract)
Yin A, Rumelhart PE, Butler R, Cowgill E, Harrison TM, Foster DA, Ingersoll RV, Qing Z, Xian QZ and Xiao FW. 2002. Tectonic history of the Altyn Tagh Fault system in northern Tibet inferred from Cenozoic sedimentation. Geological Society of America Bulletin, 114(10): 1257-1295
Yin A, Dang YQ, Zhang M, Chen XH and Mcrivette MW. 2008. Cenozoic tectonic evolution of the Qaidam Basin and its surrounding regions (Part 3): Structural geology, sedimentation, and regional tectonic reconstruction. Geological Society of America Bulletin, 120(7-8): 847-876
Zhang WL. 2006. High-resolution megnetostratigraphy of the Cenozoic Qaidam Basin, implications for the uplift of Tibetan Plateau. Ph. D. Dissertation. Lanzhou: Lanzhou University (in Chinese with English summary)
Zhou Y and Pan YS. 1999. The initial shear sense of the Allun Fault and its timing. Geological Review, 45(1): 1-9 (in Chinese with English abstract)
Zhu L, Wang C, Zheng H, Xiang F, Yi H and Liu D. 2006. Tectonic and sedimentary evolution of basins in the northeast of Qinghai-Tibet Plateau and their implication for the northward growth of the plateau. Palaeogeography, Palaeoclimatology, Palaeoecology, 241(1): 49-60
李海兵, 杨经绥, 许志琴, 孙知明, Tapponnier P, van der Woerd J, Meriaux AS. 2006. 阿尔金断裂带对青藏高原北部生长, 隆升的制约. 地学前缘, 13(4): 59-79
刘良, 陈丹玲, 王超, 张成立. 2009. 阿尔金, 柴北缘与北秦岭高压-超高压岩石年代学研究进展及其构造地质意义. 西北大学学报(自然科学版), 39(3): 472-479
王亮, 肖安成, 巩庆霖, 刘东, 沈中延, 周苏平, 吴磊, 楼谦谦, 孙晓文. 2010. 柴达木盆地西部中新统内部的角度不整合及其大地构造意义. 中国科学(地球科学), 40(11): 1582-1590
吴磊. 2011. 阿尔金断裂中段新生代活动过程及盆地响应. 博士学位论文. 杭州: 浙江大学
伍跃中, 李荣社, 王战, 雷学武, 张转, 谢丛瑞. 2007. 阿尔金山各边界断裂的归属性. 地球科学, 32(5): 662-670
杨藩, 马志强, 许同春, 叶素娟. 1992. 柴达木盆地第三纪磁性地层柱. 石油学报, 13(2): 97-101
张伟林. 2006. 柴达木盆地新生代高精度磁性地层与青藏高原隆升. 博士学位论文. 兰州: 兰州大学
周勇, 潘裕生. 1999. 阿尔金断裂早期走滑运动方向及其活动时间探讨. 地质论评, 45(1): 1-9