论文部分内容阅读
四川盆地页岩气勘探已在川东南—川南海相下志留统、川东—川东北湖相下侏罗统泥页岩层系获得了商业发现和工业气流,展示了四川盆地页岩气具有多领域、多层系、多类型的特点。采用氩离子抛光—扫描电镜、压汞—吸附联合测定、脉冲渗透率和X-射线衍射等实验测试方法,通过对海相、湖相泥页岩沉积相、生烃条件、储集特征、可压裂性和富集类型多方面对比表明,海相龙马溪组优质页岩主要发育于克拉通台内凹陷深水陆棚沉积,具有分布广,厚度稳定,有机碳含量高,有机质孔、页理、有机硅均发育的良好的生、储、可压裂一体的页岩气物质基础,3类页岩气富集类型(盆内超高压页岩气型、盆内缘超压页岩气型和盆外常压页岩气型),其中盆内超高压页岩气型和盆内缘超压页岩气型为最有利的页岩气勘探类型;湖相大安寨段有利的页岩与灰岩薄互层岩性组合,主要发育于最大湖进期碳酸盐岩湖泊的湖坡风暴滩与湖坡泥交替沉积环境,具累计厚度大,有机碳含量较高,粒缘孔缝发育,渗透性较好,钙质脆性矿物含量高的较好的生、储、可压裂近配的页岩气物质基础,是湖相有利的页岩气勘探类型。针对海、湖相不同类型页岩气的形成特点,开展适应性勘探开发技术的攻关,是实现多领域页岩气经济有效开发的关键。
Shale gas exploration in the Sichuan Basin has obtained commercial discoveries and industrial gas flows in the Lower Jurassic shale formations in the southeastern Sichuan-South Sichuan Sea facies, and shows that the shale gas in the Sichuan Basin has Multi-field, multi-tiered, multi-type features. The experimental methods such as argon ion polishing - scanning electron microscopy, mercury intrusion - adsorption determination, pulse permeability and X - ray diffraction were used to study the sedimentary facies, hydrocarbon generation conditions and reservoir characteristics of marine and lacustrine mud shale. Comparisons of fracturing and enrichment types show that the high-quality shale in the marine Longmaxi Formation mainly develops in deep-water shelf sediments in the craton Passai depression and has the characteristics of wide distribution, stable thickness, high organic carbon content, organic matter pores, , Organic silicon have developed a good raw, reservoir, fissile integrated shale gas material base, three types of shale gas enrichment types (ultra-high pressure shale gas in the basin, overpressured shale gas And the normal pressure shale gas type outside the basin). Among them, ultra-high pressure shale gas and overpressured shale gas in the basin are the most favorable shale gas exploration types. The favorable shale in the Daanzhai section of the lake facies and The limestone and thin interbedded lithologic assemblages are mainly developed in the alternate lake and lake slopes with the largest lacustrine carbonate rock lakes and mud deposits with large accumulative thickness and high organic carbon content, , Better permeability, better calcium content of calcium fragile minerals, storage, fracturing The material basis of shale gas, is advantageous lacustrine shale gas exploration type. In view of the formation characteristics of different types of shale gas in the sea and lakes, it is the key to realize the economical and effective development of shale gas in various fields to carry out research on adaptive exploration and development technologies.