辽河西部凹陷优质页岩层段岩石学类型及其有机地球化学特征  

Petrology types and organic geochemical characteristics of shale in the Western Depression,Liaohe

作　　者：毛俊莉[1,2] 荆铁亚[3] 韩霞[2] 尚灿[2] 黄双泉[2] 马满兴[2] 

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]辽河油田勘探开发研究院,辽宁盘锦124010 [3]中国华能集团清洁能源技术研究院有限公司,北京102209

出　　处：《地学前缘》2016年第1期185-194,共10页Earth Science Frontiers

基　　金：国家科技重大专项(2009GYXQ-150704);中石油重大攻关课题(2011A-4804)

摘　　要：本文从辽河西部凹陷岩心观察入手,结合岩石薄片鉴定与X衍射全岩定量分析技术,完善了湖相泥质岩类岩石学分类方法。根据新的分类方案,页岩可分为黏土型页岩、长英型页岩和混合型页岩等。其中黏土型页岩呈密集层状构造,黏土矿物为主,有机质层状富集,发育在陆源输入相对较弱的环境里;长英型页岩以泥级石英长石为主,镜下层状结构不明显,发育于陆源输入较强的淡水沉积环境;混合型页岩中发育黏土矿物、长英质和碳酸盐岩矿物,无主体成分,有机质以湖泊藻类为主,有机质纹层与黏土或者与碳酸盐岩纹层间互层结构,发育在微咸水至咸水的闭塞湖相环境。有机地化分析和生烃动力学实验研究表明半深湖相-深湖相的具有纹层结构黏土型页岩及混合型(含碳酸盐质)页岩,有机质类型以Ⅰ-Ⅱ1型为主,生烃能力很强,长英类页岩和块状泥岩次之。混合型页岩主要分布盘山洼陷沙四上亚段杜二层段和高升层段,黏土型页岩主要分布在杜家台和曙光斜坡区沙四上亚段杜一层段。混合型页岩区为油田公司近期非常规油气勘探的主攻方向。Based on the core observation of the Western Sag of Liaohe,combined with rock slice and X-diffraction quantitative analysis of whole rock,this study improves the lacustrine mudstone lithology classification method.According to the new classification scheme,shale can be divided into three types：clay shale,felsic shale and mixed shale.Clay shale is characterized by dense layer structure and organic layered enrichment.It is dominated by clay minerals and developed in the environment with relatively weak,terrestrial input.The felsic shale mainly consists of mud-scale quartz feldspar with unclear layered structure under microscope.It is developed in the freshwater sedimentary environment with strong terrigenous input.Mixed shale consists of clay minerals,carbonate and felsic minerals,no main composition.Organic matter is dominated by lucstrine alage.Organic laminae is interbedded with clay or carbonate laminae.It is developed in occlusion lacustrine environment with brackish water to salt water.Organic geochemical analysis and hydrocarbon generation kinetic experiments show that the organic matter of the clay shale and mixed shale（including carbonate type）developed in the semi-deep to deep lake with laminated structure is dominated by type Ⅰ-Ⅱ1.It has strong hydrocarbon generation potential,and is followed by felsic shale and massy mudstones.Mixed shale is mainly distributed in the Du2 and Gaosheng sections of the upper 4th Member of Shahejie Fm.of Pansan sub-sag.Clay shale is mainly distributed in the Du1 section of the upper 4th member of Shahejie Fm.in the Dujiatai and Shuguang slope areas.Mixed shale area is the main direction of unconventional oil and gas exploration of the oil field.

关 键 词：泥页岩分类 页岩岩石学 地球化学特征 辽河西部凹陷 

分 类 号：P618.130.21[天文地球—矿床学]