上扬子地区五峰组—龙马溪组优质页岩沉积主控因素

发布时间：2018-01-08 00:09

本文关键词：上扬子地区五峰组—龙马溪组优质页岩沉积主控因素　出处：《天然气工业》2017年04期 　论文类型：期刊论文

【摘要】：为揭示上扬子地区优质页岩的分布规律和沉积主控因素,基于四川盆地南部(以下简称川南)野外露头剖面和钻井资料,结合地球化学元素测试和生物地层分析结果,从板块运动、海平面变化、古生产力、沉积速率、古地理环境等方面研究了该区上奥陶统五峰组—下志留统龙马溪组页岩的分布规律和沉积主控因素。结果表明:①扬子地块与周缘地块的碰撞、拼合及板内变形作用总体呈现早期和缓、晚期强烈,西北部和缓、东南部强烈的态势,造就了上扬子沉降沉积中心向西北迁移,川南海域封闭性出现早期弱、晚期强的演化特征;②海平面在奥陶纪—志留纪之交呈现由深→浅→深→浅的旋回变化,早期的高海平面与稳定海盆配置,形成了海底大面积缺氧、有机质有效保存的构造沉积空间;③受构造活动和海域封闭性的影响,川南海域古生产力呈现早期高、晚期低的变化趋势,沉积速率则表现为早期慢、晚期快的变化特点;④富有机质、富硅质页岩的规模沉积和分布主要受缓慢沉降的稳定海盆、相对较高的海平面、半封闭水体和低沉积速率等因素的控制。结论认为:①该区优质页岩多期叠置、横向连片、沉积时代向西北不断变新,优质页岩形成主要在五峰期—鲁丹期,其次为埃隆期;②主力勘探层系在川南—川东坳陷区为五峰组—鲁丹阶,在威远地区为鲁丹阶—埃隆阶,在川中—川北地区则为五峰组—特列奇阶。
[Abstract]:For the distribution and deposition of the master to reveal the upper Yangtze area of shale factors, southern Sichuan basin (hereinafter referred to as Sichuan) based on the outcrop and drilling data, combined with the geochemical test and biostratigraphic analysis results from plate movement, sea level change, paleo productivity, deposition rate, paleogeographic environment etc. study on the distribution and deposition of the main control area of Upper Ordovician five peak - Lower Silurian Longmaxi shale factors. The results show that the collision of the Yangtze block and the surrounding block, split and intraplate deformation in general is early and late, strong, northwest and Southeast, strong the situation, created the sedimentation center migrated to the northwest, South Sichuan area closed early weak, the evolution characteristics of late strong; the sea level in the Ordovician Silurian to show from deep to shallow to deep and shallow. To change the high sea level and stable basin configuration early, forming a large area of seafloor anoxia, tectonic and sedimentary organic matter preservation space effectively; the waters closed by tectonic movement and the influence of Sichuan, the southern waters of paleo productivity showed an early trend of advanced high, low, deposition rate is early slow. The change characteristics of advanced fast; the organic rich, scale deposition and distribution of rich siliceous shale is mainly affected by the stable slow subsidence of the basin, the sea level is relatively high, control of semi enclosed water bodies and low deposition rate and other factors. The conclusion is: the area of shale multi-phase superimposition and sedimentary Era to laterally. The constant changes of shale formation, mainly in the five peak - Lu Danqi, followed by eilon period; the main exploration strata in South Sichuan Sichuan depression area five peak group - Lu Danjie, in the Weiyuan area for Lu Dan eilon - order order, in Sichuan In North Sichuan area is five of peak - telychian.

【作者单位】：中国石油勘探开发研究院;
【基金】：国家重点基础研究发展计划(973计划)项目(编号:2013CB228001) 国家科技重大专项(编号:2011ZX05018-001)
【分类号】：P618.13
【正文快照】： Main factors controlling the sedimentation of high-quality shale inWufeng Longmaxi Fm,Upper Yangtze regionWang Yuman,Li Xinjing,Dong Dazhong,Zhang ChenchenWang Shufang(Petro China Petroleum ExplorationDevelopment Research Institute,Beijing 100083,Chin

【相似文献】