摘要
受中三叠世末印支运动早期的影响,川西地区中三叠统碳酸盐岩普遍受到剥蚀和岩溶作用。通过多口井和多个露头剖面的岩心、岩屑观察分析和地球化学分析表明,该区中三叠统雷口坡组顶,古表生岩溶特征明显。古岩溶作用为雷口坡组顶储层的发育创造了条件,雷口坡组上部发育了一套岩溶孔隙型储层,主要分布于四段上亚段,在新场地区储层段累计厚度达38~75m,岩性主要为微—粉晶白云岩、灰质白云岩、白云质灰岩、(藻)砂屑白云岩及(藻)砂屑灰岩等,以Ⅱ—Ⅲ类储层为主。认为该套储层的发育主要受岩性组合、微古地貌及埋藏期岩溶作用控制。
By influence of early Indosinian movement,the middle Triassic carbonate rocks were generally subjected to denudation and karstification in western Sichuan Basin. Observation and geochemical analysis of cores and rock debris from several wells and outcrops show many distinct features of epikarstification on the upper part of Middle Triassic Leikoupo Formation. The paleokarstification created good conditions for reservoir development on the upper part of Leikoupo Formation. A set of porous karst reservoirs develops in the Upper Submember of Leikoupo 4th Member, which mainly consists of dolomicrite, crystalline dolostone, lime-dolostone, dolomitic limestone and algal dolarenite/ calcarenite and is 38-75 m of accumulated thickness in Xinchang Gas Field. The Leikoupo 4th Member reservoirs are mainly TypesⅡ and Ⅲ. It is deemed that the development of reservoirs is controlled by lithology combination, microtopography and burial karstification.
出处
《海相油气地质》
北大核心
2013年第2期8-14,共7页
Marine Origin Petroleum Geology
关键词
雷口坡组
岩溶作用
岩溶储层
储层特征
控制因素
四川盆地西部
Middle Trassic
Leikoupo Formation
Karstification
Karst Reservoir
Reservoir characteristics
Controllingfactor
Sichuan Basin