川西地区中三叠统雷口坡组古岩溶储层特征及发育主控因素

作    者:宋晓波,王琼仙,隆轲,许国明,石国山,冯霞,邓强,蔡左花
单    位:中国石化西南油气分公司勘探开发研究院贵阳研究所
基金项目:
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。
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

Characteristics and Main Controlling Factors of Middle Triassic Leikoupo Paleokarst Reservoirs in Western Sichuan Basin

Author's Name: Song Xiaobo, Wang Qiongxian, Long Ke, Xu Guoming, Shi Guoshan, Feng Xia, Deng Qiang, Cai Zuohua
Institution: Guiyang Institute of Exploration & Production Research Institute,SNOPEC Southwest Oil and Gas Branch Company
Abstract:
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 TypesⅡand Ⅰ. It is deemed that the development of reservoirs is controlled by lithology combination,microtopography and burial karstification.
Keywords: Middle Trassic; Leikoupo Formation; Karstification; Karst Reservoir; Reservoir characteristics; Controlling factor; Sichuan Basin
投稿时间: 2012-08-28  
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