古地理学报2012，Vol.14Issue(4)：477-486,10.
四川盆地上三叠统小塘子组沉积特征及地质意义
Depositional characteristics and its geological significance of the Upper Triassic Xiaotangzi Formation in Sichuan Basin
摘要
Abstract
Correct understanding of depositional systems of the Upper Triassic Xiaotangzi Formation of Sichuan Basin, is not only conducive to the restoration of the early Late Triassic palaeogeography, but also helps to be a correct evaluation of hydrocarbon potential. Comprehensive analysis of outcrops and single well manifest 3 types of depositional systems, namely, delta, barrier island-lagoon and shallow shelf, developed. Delta depositional systems are mainly distributed in the northwest and southwest of Sichuan, with a small delta developed in central Sichuan. Barrier island-lagoon depositional system is chiefly located in central and southern Sichuan, shallow shelf depositional system situated in the middle of western Sichuan Basin. In the Late Triassic, collision of the Yangtze Plate and North China Plate closed from east to west, leading to uplifting of the northern section of the Longmenshan Mountain and formation of the delta depositional systems in northern Sichuan. Provenance of the southern section of the western Sichuan is from Kangdian Old Land. In central and southern Sichuan, because of flat terrain and strong tidal reworking, a barrier island-lagoon depositional system formed. Be a large area of distribution of thick source rocks, with II - III kerogen mainly argillaceous source rock has a wide scope of carbon content and high organic carbon content of maturity. In shallow shelf areas and the lagoon subfacies, source rock with type II kerogens based, TOC content has the highest average content of greater than 2% . In remote sand bar and prodelta, TOC content is higher, ranging from 2% to 3%, and type III kerogen based.关键词
古地理/烃源岩/小塘子组/上三叠统/四川盆地Key words
palaeogeography, source rock, Xiaotangzi Formation, Upper Triassic , Sichuan Basin分类
天文与地球科学引用本文复制引用
施振生,赵正望,金惠,宋海敬..四川盆地上三叠统小塘子组沉积特征及地质意义[J].古地理学报,2012,14(4):477-486,10.基金项目
国家重点基础研究发展规划(973)项目(编号:2007CB209504)资助 （973）
