胜利油区早古生代沉积相

EARLY PALAEOZOIC SEDIMENTARY FACIES IN THE SHENGLI OIL PROVINCE,NORTH CHINA PLATFORM

关键词:  胜利油区  早古生代  沉积相  沉积旋回  油气勘探

Key words:  Shengli oil province  Early Palaeozoic  sedimentary fades  depositional cycles  oil and gas exploration

摘要:

早古生代,胜利油区作为华北地台的一部分,接受了一套以海相碳酸盐岩为主的沉积,其沉积相与其他地区既有相似性,又有特殊性。文中首先按沉积岩类型,将沉积相划分为碎屑沉积相系和碳酸盐岩沉积相系。根据岩石的沉积构造、指相矿物、生物化石等,将下古生界沉积相进一步划分为4个相9种亚相,并对各种相的特征进行了简要说明。在单井相分析的基础上,利用单因素和三端元作图法编制了基础图件,结合相序的变化规律和区域地质背景,对区内早古生代不同时期的沉积相展布特征进行了探讨;馒头期一徐庄期,基本为潮上到潮间带;张夏期一崮山期,发育有潮下浅滩和开阔海两种主要沉积相;长山期一早奥陶世,以潮间一潮下带为主;中奥陶世,以浅水的潮上、潮问带与较深水的潮下带间互出现。研究早古生代沉积相,对于评价碳酸盐岩储层和烃源岩有重要意义。

Abstract:

The marine carbonate sediments were laid down during the Early Palaeozoic in the Shengli oil province as part of the North China platform.The sedimentary facies in the study area consist of clastic sedimentary facies series and carbonate sedimentary facies se-ries according to sedimentary rock types,and the Lower Palaeozoic sedimentary facies may be subdivided into four facies and nine subfacies in the light of sedimentary structures,di-agnostic minerals and fossil organism.The present paper gives a more detailed description of the characteristics of the above-mentioned sedimentary facies in different stages of the Early Palaeozoic.For instance,the sedimentary facies comprise supratidal to intertidal zones during the Mantouan and Xuzhuangian,subtidal shoal and open sea facies during the Zhangxian and Gushanian,intertidal and subtidal zones during the Changshanian and Early Ordovician,the alternation of the shallow-water supratidal and intertidal zones and deeper-water subtidal zone during the Middle Ordovician.The research in this study is believed to have important implications for the evaluation of the carbonate reservoirs and source rocks in the study area.