摘要
通过露头、岩心、薄片、矿物X衍射、氩离子抛光、扫描电镜及钻井资料的综合研究,在上扬子地区寒武系梅树村组沉积期—筇竹寺组沉积期沉积地层中识别出9种页岩岩相、5类沉积相标志,提出了页岩沉积相类型精细划分方案,建立了页岩沉积演化发育模式。指出梅树村组沉积期与筇竹寺组沉积期在沉积作用方式、沉积体系类型及沉积相分布上均存在差异:梅树村组沉积期以机械-化学沉积和生物沉积为主,主体为碳酸盐缓坡台地—陆棚—斜坡—深水盆地沉积体系;筇竹寺组沉积期以砂质机械沉积、泥质絮凝及生物沉积为主,主体为滨岸—陆棚—斜坡—深水盆地沉积体系。资阳—长宁近南北向展布的地区、东南部鄂西—渝东—黔中及东北部宜昌—房县一线的地区为两个深水陆棚相富有机质页岩沉积中心,是页岩气勘探有利地区,但前者富有机质页岩以多层、薄层为特点,后者以连续厚层为特点,今后应考虑其差异进行有针对性的页岩气勘探部署。
Based on comprehensive analysis of outcrops, cores, rock thin sections, mineral X-ray diffraction and Argon ion-milling - scanning electron microscopy, nine lithofacies types and five facies marks in the Lower Cambrian Meishucun Formation and Qiongzhusi Formation in the Upper Yangtze are identified, a classification scheme of the shale sedimentary facies is proposed, and the deposition and evolution model of the shale in the Lower Cambrian is figured out. This research shows there are difference in sedimentation, types and distribution of the sedimentary facies in the Meishucun Formation and Qiongzhusi Formation. The main sedimentation modes in the Meishucun Stage were mechanical-chemical and biological sedimentation, the sedimentary facies （from west to east） were carbonate ramp, shelf, and slope and bathyal basin. The main sedimentation of the Qiongzhusi Stage was clastic mechanical, argillaceous flocculation and biological deposition, and the sedimentary facies were shore, shelf, and ramp and bathyal basin. There are two depositional centers of rich organic shale in the Upper Yangtze which are the prospective area for shale gas exploration. The first one is in the Ziyang-Changning area in nearly north-south strike, which is characterized by multiple thin layers. The other one is in the Western Hubei-Eastern Chongqing-Middle Guizhou and Yichang-Jianshi-Fangxian, which is characterized by the thick-layer shale. The shale gas exploration in these areas in the future should take pertinent strategies in line with their differences.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2017年第1期21-31,共11页
Petroleum Exploration and Development
基金
国家自然科学基金项目(41202103)
中国石油化工股份有限公司科技开发部项目(P15114)
关键词
页岩
岩相
沉积相
下寒武统筇竹寺纽
下寒武统梅树村组
上扬子地区
四川盆地
shale
lithofacies
sedimentary facies
Lower Cambrian Qiongzhusi Formation
Lower Cambrian Meishucun Formation
Upper Yangtze area
Sichuan Basin
