摘要
综合运用元素ICP-AES分析、地质录井等资料,结合古生物观察、镜下薄片观察及全岩矿物X衍射分析等手段,利用定性和定量相结合的方法,对东营凹陷始新统红层的古沉积环境进行了恢复。研究认为:红层沉积时期古气候干旱,孢粉以裸子植物为主,被子植物次之,大多为旱生的麻黄粉属和三肋麻黄粉;红层为陆上暴露环境中的氧化沉积物,古水介质的古盐度较高,为淡水一微咸水环境,水介质呈现弱碱性一碱性特征;古沉积环境对沉积相类型、成岩作用特征具有一定的控制作用,古气候和水介质氧化还原性决定沉积相类型及沉积体系的展布特征,形成了"冲积扇一洪水一漫湖一盐湖"过渡的沉积体系,水介质的古盐度和酸碱性控制了早期成岩作用,对埋藏成岩作用具有一定的影响,形成了大量早期碳酸盐胶结物,为后期的溶蚀作用奠定了物质基础。
Integrating ICP-AES element analysis, mud logging and other data, and moreover combining with the paleontologic and thin-section observations, full rock mineral X diffraction analysis and other means, the recovery of palaeosedimentary environment in Eocene red formations of Dong3/ing Sag is conducted with the integration of qualitative and quantitative methods. The results show that during the period of red formation deposition, the sporopollens are mianly from the gymnosperms, the next is angiosperms, most of them are xeric and three-rib Ephedripites; red formations are the oxidation deposit in the exposed environment on land. The paleosalinity of the palaeo-aqueous media are rather high, the fresh and brackish water environments are determined, the media are characterized by alkalescence and alkalinity. The types of sedimentary facies and diagenesis features are controlled to a certain degree by the palaeosedimentary environment, the former and distribution characteristics of the depositional system are determined by the redox conditions of the palaeoclimate and water media, thus the transitional depositional system of ＂ alluvial-fan-floods-diffuse lake-salt lake＂ is generated. The early diagenesis is controlled by the paleosalinity and pH of the media, and furthermore they have a certain impact on the burial diagenesis. In the end, a large number of early canbonate cements are formed, thus the material foundation for late dissolution is laid.
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2013年第2期43-48,共6页
Petroleum Geology & Oilfield Development in Daqing
基金
国家油气科技重大专项(2008ZX05051)
中央高校基本科研业务费专项资金(11CX06004A)资助
