第38卷第5期 2017年10月
文章编号：10013873(2017)050524-06
新疆石油地质
XINJIANGPETROLEUM GEOLOGY DOI:10.7657/XJPG20170504
Vol.38,No.5 Oct.2017
准噶尔盆地腹部中生界地层水特征及油气地质意义
宫亚军
（中国石化胜利油田分公司勘探开发研究院，山东东营257000）
摘要：地层水作为油气运移和聚集的介质，对油气成藏具有重要指示意义。为深入认识两者之间的内在关系，在准噶尔盆地腹部中生界水动力体系划分的基础上，分析了水动力体系内地层水的压力、矿化度、类型，以及含油气性特征，并结合地层水的来源及成因机制分析，阐述了地层水的油气地质意义。结果表明，研究区中生界纵向发育3大水动力体系，形成3大类10小类地层水类型。NaHCO,型地层水主要与地表淡水、泥页岩压释水及有机质生烃等有关； Na,SO.型地层水主要起源于盐岩溶水的下渗和煤系烃源岩的生排烃；CaCl型和MgCl,型地层水则受正向浓缩及离子交换作用控制。不同地层水类型的油气差异性取决于含烃流体是否充注、充注时序及充注程度，对于地质过程中的
一系列流体充注，含烃流体充注越早，充注持续时间越长，充注度超高，则油气富集程度越高。关键调：准噶尔盆地；中生界；水动力体系；地层水；流体成因；油气成藏
中图分类号：TE124.2
文献标识码：A
Mesozoic Formation Water Characteristics and Hydrocarbon Geological Significance in the
Hinterland of JunggarBasin
GONGYajun
(Research Institute of Exploration and Development, Shengli Oilfield Company,Sinopec, Dongying, Shandong 257000, China)
Abstract: As a medium for hydrocarbon migration and accumulation, formation water plays an important role in oil and gas entrapment. In order to further understand the relationship between formation water and hydrocarbon accumulation, based on hydrodynamic system classi adod ueaqe [ro pue ad iues anssad sazkeue aded useq egun jo puey u oey aeosa o uoeag ties of the formation water in the hydrodynamic system, and demonstrates geological significance of the formation water by combining with the analyses on formation water origin and its genetic mechanism. The results show that 3 hydrodynamic systems are developed vertically in the Mesozoic strata; the formation water can be divided into 10 subclasses of 3 types. NaHCO,-type formation water is mainly related to sur-face fresh water, compaction released water of shales and hydrocarbon generation of organic matter; Na;SO,-type formation water mainly originates from infltration of saline karst water and hydrocarbon generation and expulsion of coal-measure souree rocks; CaCl-type and Mg Cl-type formation water are controlled by forward concentration and cation exchange. The differences of hydrocarbons with different forma-tion water types depend on whether the hydrocarbon-bearing fluid is charged, charging sequence and duration and charging degree. For a series of fluid charging during geological processes, the earlier the hydrocarbon-bearing fluid charges, the longer the charging duration and the higher the charging degree is, the higher the hydrocarbon enrichment degree will be.
Keywords: Junggar basin; Mesozoic; hydrodynamic system; fomation water; fluid genesis; hydrocarbon accumulation
盆地内地层水与油气通常具有独特的共生组合关系。开展这方面的研究对揭示油气成藏规律、降低勘探风险等有重要意义(I-。本文以准噶尔盆地腹部中生界地层水分析数据为基础，研究了地层水类型、主离子组合、矿化度、压力及其与含油气性之间的关系，进而分析中生界地层水的类型、来源、成因机制及其油气地质意义。
研究区成藏地质背景 1
准噶尔盆地腹部具凹凸相间的构造格局(图1)。
收稿日期：2017-05-31
修订日期：201708-01
中生界现今已发现油气主要来自二叠系下乌尔禾组和侏罗系八道湾组2套主力烃源岩。燕山运动早期，二叠系下乌尔禾组烃源岩成熟，伴随燕山运动中期断裂活动强烈，车排子一莫索湾古隆起形成，构造转换带发育大型断裂体系沟通烃源岩和储集层6-}，二叠系油气首次大规模跨体系充注，并沿构造转换带及古隆起分布。燕山运动晚期一喜马拉雅运动早期，中生界整体沉降并南倾，二叠系烃源岩进人生烃高峰期，中拐凸起沙2井区、莫索湾凸起莫西庄油田等油气充注，早期油藏沿保罗系砂体等横向调整，陆梁油田等更
基金项目：国家科技重大专项（2016ZX05002-002）；中国石化股份公司课题（P16040）
作者简介：宫亚军（1984-），男，甘肃正宁人，工程师，油气成激，（Tel)18754612677(E-mail)278365907@qq.com 万方数据