摘要
根据岩心及其分析化验资料,从岩石的颜色、成分、结构、有机质丰度等方面划分泥页岩岩相类型;从古气候、古物源、古水深、古盐度和古水体的氧化还原性5个方面分析古环境,建立环境指标分级量化标准。研究结果表明,东营凹陷沙四上亚段—沙三下亚段沉积环境特征具有气候由干燥—半干燥—半潮湿,水体由半深水到深水、从强还原性逐渐到还原性、盐度从盐水到咸水到半咸水,物源从较少到较多的规律变化,共划分了6个环境组合;并建立了沉积环境与泥页岩岩相之间的关系,即有机质丰度主要受盐度控制,盐水区为含有机质的岩相,咸水区和半咸水区为富有机质的岩相;结构主要受气候和水深控制,气候干燥—半干燥、半深水环境发育纹层状的岩相,气候半潮湿、深水环境发育层状的岩相;岩性主要受气候和物源控制,气候干燥、物源少的环境发育泥质灰(云)岩和灰(云)岩的岩相,气候半潮湿、物源较多的环境发育灰质泥岩的岩相。
According to the core color, component, structure organic matter abundance of system cored wells, shale facies of the lower Es3-upper Es4 in Dongying sag were divided. The ancient environment was analyzed by climate, provenance, water depth, salinity, oxidation and reduction, and a standard of classification and quantification was established. The findings in-clude: climate from arid to semiarid to semi-humid, water from semi-deep to deep and strong reduction to reduction, salinity from saline to salt to brackish, and provenance from less to more. The ancient environment can be divided into six environ-mental combinations. This study establishes the following relationships between the sedimentary environment and facies. The organic matter content of shale facies are mainly affected by salinity: saline range develops less organic matter facies, and salt and brackish range develops rich organic matter facies. Structure of shale facies are mainly controlled by climate and water depth: arid and semiarid climate and semi-deep water environment develops lamina facies, and semi-humid climate and deep water develops stratiform facies. Lithology of shale facies are mainly affected by climate and provenance: arid climate and less provenance environment develops argillaceous limestone and limestone, and demi-humid climate and more provenance environment develops lime mudstone.
出处
《中国石油大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2015年第4期19-26,共8页
Journal of China University of Petroleum(Edition of Natural Science)
基金
国家'973'计划项目(2014CB239104)
关键词
东营凹陷
泥页岩岩相
沉积环境
古气候
Dongying sag
shale facies
sedimentary environment
climate