文档介绍：The Factors Controlling the Reservoirs Forming of
Y gas fields in Jinxi flexural fold beltOrdos Basin
A Dissertation Submitted for the Degree of Master
Candidate:Cao Baidi
Supervisor: Wang Feng
Prof. Zheng Congbin
Chang’an University, Xi’an, China
摘要
Y 气田位于鄂尔多斯盆地晋西挠褶带,近年来该区的天然气勘探取得了重大突破,
发现了高产气藏和多口工业气流井,展示了该区天然气勘探的良好前景。
Y 气田属于低孔、低渗、低丰度、大面积分布的隐蔽性气藏,与构造油气藏相比
较,隐蔽性气藏形成机制及分布规律复杂,勘探难度大,技术要求高。
气田主力气层富存于二叠系太原组、山西组和石盒子组地层中,其下伏地层为中
奥陶统马家沟组,两者呈平行不整合接触,其上覆地层为下三叠统的刘家沟组。早期
构造的稳定沉降,为本区本溪组、太原组、山西组的海相烃源岩奠定了烃源岩发育的基
础,而山西组和石盒子组较为发育的砂岩作为储层,上石盒子组和石千峰组的泥岩作
为本区盖层,三者构成良好的生储盖组合。晚期构造的持续抬升,控制了天然气运聚的
指向,而岩性-成岩圈闭的多层段发育,构成了下生上储式、自生自储式及穿越式三种
生储盖组合。
综上,本文通过现代油气勘探理论和技术方法,以上古生界沉积特征与后期构造
演化为基础,以烃源岩生烃后运移为线索,以高渗储层成因与天然气富集成藏为重点,
进行古生界地质综合研究,结合典型气藏的解剖,建立上古生界天然气成藏模式,进
一步总结天然气主控因素,评价天然气勘探潜力,为该区下一步隐蔽油气藏的勘探开
发提供了思路。
关键词:鄂尔多斯盆地, 晋西挠褶带, 岩性油气藏, 天然气成藏特征, 成藏模式
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Abstract
Y gas field is located in the Jinxi flexural fold belt in Ordos Basin. In recent years, gas
exploration obtains important breakthrough with high-yield gas reservoir and multi-port
industrial air well being found, showing good prospects for gas exploration in the area.
Y gas belongs to the hidden gas reservoir with low porosity, low permeability, low
abundance and large distribution area. Compared with structural reservoir, hidden gas
reservoir has characteristics plex formation mechanism and distribution law, difficult
exploration and high technical requirements.
Main gas reservoirs overlie in the strata of PermianTaiyuan, Shanxi and Shihezi,
which parallel sunconformity to underlying strata of Middle Ordovician Majiagou
Formation, the overlying strata is lower Triassic settlement of earlier
structures laied the foundation for marine source rocks development in the group Taiyuan,
Benxi and Shanxi. Sandstone developed in the Shanxi and Xiashihezi group became
reservoirs, mudstone developed in