川西地区中二叠统栖霞组沉积体系  

Depositional system of the Middle Permian Qixia Formation in the western Sichuan Basin

作　　者：魏国齐[1] 杨威[1] 朱永刚[2] 金惠[1] 李跃纲[2] 施振生[1] 沈珏红[1] 

机构地区：[1]中国石油天然气股份有限公司勘探开发研究院廊坊分院,河北廊坊065007 [2]中国石油天然气股份有限公司西南油气田分公司川西北气矿,四川江油621700

出　　处：《石油与天然气地质》2010年第4期442-448,共7页Oil & Gas Geology

基　　金：国家"十一五"油气重大专项(2008ZX05007-002)

摘　　要：通过对川西地区中二叠统栖霞组大量露头和岩心的观察分析及样品的分析化验,认为栖霞组主要发育生物(屑)石灰岩、砂屑石灰岩、泥晶石灰岩和豹斑石灰岩;主要发育3种生物组合,即腕足类-藻类-有孔虫类组合、珊瑚组合和薄壳腕足类组合,它们分别是台地、斜坡和斜坡-盆地环境的产物。从大地构造背景、台地边缘滩特征、斜坡-盆地相特征及斜坡相与台地边缘相带的关系等方面分析,认为川西地区栖霞组为碳酸盐镶边台地沉积体系,主要的沉积相为斜坡相、台地边缘滩相和开阔台地相;其中,台地边缘滩相是栖霞组重要的储层,分布范围广。Observation and analysis of numerous outcrops and cores as well as laboratory tests of samples from the Qixia Formation in western Sichuan Basin reveal that the formation mainly consists of bioclastic limestone, calcarenite, micrite, and leopard limestone. There are mainly three fossil assemblages, including brachiopods-al- gae-foraminifera, corals and thin shell brachiopods. They were formed in platform, slope and slope-basin environ- ments respectively. Judging from geotectonic settings, bank features of platform edge and slope-basin facies, and the relationship between slope facies and platform edge facies etc, we conclude that the Qixia Formation in wes- tern Sichuan Basin is the carbonate-fringed platform depositional system with slope, platform edge bank and open platform as the main facies, of which the platform edge bank facies is widely distributed and the most favorable for hydrocarbon accumulations.

关 键 词：台地边缘滩相 镶边台地 沉积体系 栖霞组 中二叠统 川西地区 

分 类 号：TE121.3[石油与天然气工程—油气勘探]