克拉通盆地层序样式与烃源岩评价——以中扬子区震旦系、寒武系为例

Sequence Patterns and Evaluation of Source Rocks in Cratonic Basins——By Taking Sinian and Cambrian Systems in Mid-Yangtze Area for Example

根据中扬子区震旦纪寒武纪层序特征,提出了T型、H型、TH型层序样式,并将3种层序样式的沉积特征进行了比较,明确了层序样式的发育与烃源岩的关系。认为烃源岩的富集层段主要位于H型样式的二级层序海侵体系域(TST)中,其中TST的三级层序样式中,T型数量较多或H型数量较少。以中扬子区震旦系、寒武系为例,对2套烃源岩所在的层序样式进行了研究,以层序分析为基础,参考地化特征对2套烃源岩进行了研究及评价,指出了有利烃源岩区。

The sequence patterns in Cratonic Basins are analyzed,the sequence patterns T,H and TH are proposed.Sedimentary characteristics of these 3 patuerns are correlated,the relationship between their development and source rocks are clarified.It is considered that enrichment of the source rocks is mainly located in TST of Pattern H(GradeⅡ transgressive sequence marine domain),while in Grade Ⅲ sequence of TST,the number of Pattern T is more and H is less.The sequence patterns of these 2 sets of source rocks are studied by using Sinian and Cambrian systems for example,and based on sequence analysis,the source rocks are studied and evaluated by using geochemistry characters as reference,thus beneficial areas of source rocks are pointed out.