Source-to-sink of Late carboniferous Ordos Basin: Constraints on crustal accretion margins converting to orogenic belts bounding the North China Block

Geoscience Frontiers

Xiuwei Jiang¹  Xiaoxing Zhang²  Hao Zou²  Shuai Yang³  Mingcai Hou⁴  Shenglin Xu⁵  James G. Ogg⁵  Anqing Chen⁵ 

[1] Corresponding author. College of Earth Science, Chengdu University of Technology, Chengdu 610059, Sichuan, China.;Department of Earth, Atmospheric and Planetary Sciences, Purdue University, West Lafayette, IN, 47907, USA;Key Laboratory of Tectonic Controls on Mineralization and Hydrocarbon Accumulation of Ministry of Land and Resources, Chengdu University of Technology, Chengdu 610059, Sichuan, China;State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu 610059, Sichuan, China;

关键词: Benxi formation;    Detrital zircons;    Central asian orogen belt;    Tectonics;    Paleogeography;    Moscovian and kasimovian;   

DOI  :  

来源: DOAJ

【 摘 要 】

The Upper Carboniferous Benxi Formation of the Ordos Basin is the lowest strata overlying Middle Ordovician above the major ca. 150-Myr sedimentary gap that characterizes the entire North China Block (NCB). We apply an integrated analysis of stratigraphy, petrography, and U–Pb dates and Hf isotopes on detrital zircons to investigate its provenance and relationships to the progressive collisions that formed the Xing’an-Mongolia Orogenic Belt to the north and the Qinling Orogenic Belt to the south. The results show that, in addition to regional patterns of siliciclastic influx from these new uplifted sources, the Benxi Formation is composed of two sequences corresponding to long-term glacial-interglacial cycles during the Moscovian to lower Gzhelian stages which drove global changes of eustatic sea level and weathering. The spatio-temporal distribution of sediment isopachs and facies indicate there were two sediment-infilling pulses, during which the southern and the northern Ordos Basin developed tidal-reworked deltas. The age spectra from detrital zircons, trace element patterns and εHf(t) values reveal that the siliciclastics forming the southern delta was sourced in the Qinling Orogenic Belt, whereas the northern delta was derived from the Xing’an-Mongolia Orogenic Belt. The source-to-sink evolution of this Upper Paleozoic system records the progressive development of orogenic belts and uplifts forming on the southern and northern margins of the NCB prior to its collisions with the South China and the Siberian plates, respectively.

【 授权许可】

Unknown