Sequence stratigraphic analysis of superimposed coal measure gas-bearing system in Daning-Jixian block,eastern margin of Ordos Basin,China  

作　　者：Shizhuang YANG Song LI Wenguang TIAN Guanghao ZHONG Junjian WANG 

机构地区：[1]School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China [2]Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&Utilization,Beijing 100083,China [3]PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China [4]Klohn Crippen Berger Ltd.,Brisbane,Queensland 4101,Australia

出　　处：《Frontiers of Earth Science》2024年第3期611-622,共12页地球科学前沿（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42072198 and 42130802);the Fundamental Research Funds for the Central Universities(No.265QZ2021011).

摘　　要：The identification of superimposed gas-bearing systems in coal measures is the basis for expediting the optimization of coal measure gas co-production.Through the analysis of drill cores and log data of Upper Carboniferous Benxi Formation to the member 8 of Middle Permian Lower Shihezi Formation in Daning-Jixian block,eastern margin of Ordos Basin,four distinct superimposed coal measure gas-bearing systems were identified,and their formation mechanism was discussed from the sequence stratigraphic perspective.Type Ⅰ system mainly contains multiple coal seams,shales and sandstone layers.Type Ⅱ system is dominated by multiple coal seams and shales.Type Ⅲ is characterized by multiple sandstone layers,and type Ⅳ system is dominated by limestones and mudstones.In general,the gas-bearing systems deposited in barrier-lagoon are type Ⅱ,those deposited in carbonate tidal flats are type IV,and those deposited in the delta front are types Ⅰ and Ⅲ.The marine mudstone,acting as a key layer near the maximum flooding surface,exhibits very low permeability,which is the main factor contributing to the formation of superimposed gas-bearing systems.The sedimentary environment plays a significant role in controlling the distribution of gas-bearing systems.Notably,the vertical gas-bearing systems in the south-western region,where delta front and lagoon facies overlap,are more complex than those in the north-eastern delta front facies.

关 键 词：coal measure gas superimposed gas-bearing system sequence stratigraphic key layer 

分 类 号：P618.13[天文地球—矿床学]