Sedimentary System of Platformal Trough of Feixianguan Formation of Lower Triassic in Northern Sichuan Basin and Its Evolution
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摘要: 川北地区下三叠统飞仙关组沉积主要受开江梁平海槽控制,短期存在的海槽在其两侧形成了较为对称的类似于威尔逊相模式的碳酸盐岩沉积体系。通过详细的钻井、露头等岩石学资料的研究,认为飞仙关组主要发育蒸发台地、局限台地、开阔台地、台地边缘滩、斜坡和盆地相共六类沉积相。其盆地相较深海盆地相浅,主要发育深色泥灰岩和灰质泥岩;斜坡沉积特征明显,见浊流、碎屑流沉积,但陆棚相不发育,可能是海槽深度小、面积小引起的;随着海槽的关闭,海水变浅,海槽内部的沉积由盆地相向斜坡、台地边缘滩、开阔台地、局限台地、蒸发台地相演化特征明显;到飞四段顶部,整个川北地区均一化为局限台地相或蒸发台地相沉积。由于海槽存在时间短,沉积相在平面上和纵向上的演化过程十分清晰。随着海槽的关闭,海水向广海方向退却,台缘鲕滩也向海槽边界,即向广海方向发生了迁移,而且其发育层位逐渐变高。Abstract: Kaijiang-Liangping trough existed for 700 My.controlled the deposition of Feixianguan Formation of lower Triassic in the northern Sichuan Basin. In the short period of the trough existed, relativelysymmetrical carbonate rock sedimentary system that be analogous to Wilson facies pattern could be formed in its both sides. Through researching on petrology data of detailled drilling, outcrop and so on, Feixianguan Formation mainly developed six types of sedimentary facies including evaporate platform, restricted platform, open-platform, platform marginbeach, slope and basin facies. The basin facies that was shallower than deep-sea basin which mainly developed dark marl and lime mudstone; the depositonal characteristics of the slope facies are distinct, but shelf facies poor developed which may be for the sake of the depth of the trough, because it is so small; with the gradual close of the trough, seawater became shallow, the characteristics of the depositional evolution from basin facies to slope, platform margin beach, open-platform, restricted platform and evaporate platform within the trough are dinstinct; to the top of the Member 4 of Feixianguan Formation, all of the Northern Sichuan basin were deposited equally by restricted platform facies or evaporate platform facies. The period of the trough existed is so short that the course of evolution of sedimentary facies is quite clear in plane and longitude. With the gradual close of the trough, seawater receded toward to open sea, platform margin oolitic beaches moved toward to trough too, that was open sea, growing horizons of them rised gradually at the same time.
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Key words:
- platformal trough /
- sedimentary system /
- platform margin oolitic beach /
- pattern /
- evolution /
- Sichuan /
- Feixianguan Formation
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[1] 王一刚,文应初,张帆,等.川东地区上二叠统长兴组生物礁分布规律.天然气工业,1998,18(6):10-15[Wang Yigang, Wen Yinchu, Zhang Fan, et al. Distribution law of the organic reefs in Changxin formation of upper permian in east Sichuan. Natural Gas Industry, 1998, 18(.6):10～15] [2] 杨家静,王一刚,王兰生,等.四川盆地东部长兴组-飞仙关组气藏地球化学特征及气源讨论.沉积学报,2002,20(2):349-353[Yang Jiajing, Wang Yigang, Wang Lansheng, et al. The origin of natural gas pool,geochemistry characters of Changxin reef and Feixiangguan oolitic beach gas reservoir in Eastern Sichuan basins. Acta Sedimentologica Sinica,2002,20(2):349-353]. [3] 王一刚,刘划一,文应初,等.川东飞仙关组鲕滩储层分布规律勘探方法与远景预测.天然气工业, 2002,22(增刊):14～19[Wang Yigang, Liu Huayi, Wen Yingchu, et al. Distribution law, exploration method and prospectiveness prediction of the oolitic beach reservoirs in FeiXianGuan Formation in northeast Sichuan basin. Natural Gas Industry, 2002,(Supp.):14～19] [4] 杨雨,文应初.川东北开江-梁平海槽发育对T1f鲕粒岩分布的预测. 天然气工业.2002,22(增刊):30～32[Yang Yu,Wen Yinchu. Control of Kaijiang- Liangping trough growing on T1f oolite distribution in north east Sichuan basin. Natural Gas Industry, 2002,(Supp.):30-32] [5] 王兴志,张帆,马青,等.四川盆地东部晚二叠世-早三叠世飞仙关组礁滩特征与海平面变化. 沉积学报,2002,20(2):249-254[Wang Xingzhi, Zhang Fan, Ma Qing, et al. The characteristic of reef and bank and the fluctuation of sea level in Feixingguan period of late Permain- early Triassic, east Sichuan basin. Acta Sedimentologica Sinica, 2002,20(2):249-254] [6] 许效松,刘宝珺,赵玉光,等.上扬子西缘二叠纪-三叠纪层序地层与盆山转换耦合.北京:地质出版社:1997. 9～16[Xu Xiaoshong, Liu Baojin, Zhao Yuguang, et al. Sequence stratigraphy and basin- orogen coupling in Permain- Triassic in upper Yangtze platform. Beijing: Geological Publishing House,1997. 9～16] [7] 刘宝珺,张锦泉. 沉积成岩作用. 北京: 科学出版社, 1994. 237～255[Liu Baojin, Zhang Jinquan.Sedimentary diagenesis. Beijing: Science Press, 1994. 237～255] [8] 冯增昭.沉积岩石学(上、下册).北京:石油工业出版社,1991[Feng Zhenzhao. Sedimentary Petrography. Beijing: Petroleum Industry Press, 1991] -
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