油气田地层水分析数据的可信度评价方法与影响因素分析  

Data credibility evaluation method for formation water in oil and gas fields and its influencing factors

作　　者：李伟[1] 谢武仁[1] 武赛军[1] 帅燕华[1] 马行陟[1] LI Wei;XIE Wuren;WU Saijun;SHUAI Yanhua;MA Xingzhi(PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China)

机构地区：[1]中国石油勘探开发研究院,北京100083

出　　处：《石油勘探与开发》2025年第2期320-333,共14页Petroleum Exploration and Development

基　　金：中国石油天然气股份有限公司重大科技攻关项目“叠合盆地中下组合叠加地质构造与成因机制研究”(2023ZZ0202)。

摘　　要：针对油气田地层水样品易受污染而导致水化学性质信息数据失真的问题,开展对中国含油气盆地油气田地层水判别方法对比和数据可信度评价方法研究。结果表明:①地层水判识方法包含物理特征、水化学组成特征、水型特征、特征系数等单因素的基本方法,以及在此基础上提出的主要根据钠氯系数与脱硫酸系数相关性分析、并结合地质背景评价的数据可信度综合评价方法;②地层水判识的基本方法有利于现场对水化学数据的初步判别与数据的初步筛选,综合方法将CaCl_(2)型水分为A-Ⅰ-A-Ⅵ6种类型、将NaHCO3型水分为B-Ⅰ-B-Ⅳ4种类型进行评估,以便研究人员对水化学数据可信度开展深入评价与影响因素的分析;③采用基本方法判别地层水时,存在CO_(3)^(2-)、OH^(-)、NO_(3)^(-)等阴离子的地层水,或钠氯系数和脱硫酸系数与地质环境不符的地层水等都是有地表水侵入或施工液污染;④采用综合方法判别地层水的数据可信度时,虽然认为A-Ⅰ型、A-Ⅱ型、B-Ⅰ型和B-Ⅱ型是可信度较高的地层水,但都必须与地层环境、采样条件、凝析水、酸液、古风化壳淋滤、古大气淡水等影响因素的地质背景分析相结合,才能更有效与更准确地确定其数据可信度。The formation water sample in oil and gas fields is highly susceptible to being polluted,making the properties of formation water not be reflected truly.This paper discusses the identification methods and data credibility evaluation method for formation water in oil and gas fields of petroliferous basins within China.It is indicated that formation water is identified by some basic methods based on single factor such as physical properties,hydrochemical composition,water type and characteristic coefficient.On this basis,a comprehensive data credibility evaluation method is proposed,which is mainly realized by analyzing the correlation between sodium chloride coefficient and desulfurization coefficient and evaluating the geological setting.The basic identifying methods for formation water enable the preliminary identification of hydrochemical data and the preliminary screening of data on site.The proposed comprehensive method realizes the evaluation by classifying the CaCl_(2)-type water into types A-Ⅰ to A-Ⅵ and the NaHCO_(3)^(-)type water into types B-Ⅰ to B-Ⅵ,so that researchers can make in-depth evaluation on the credibility of hydrochemical data and analysis of influencing factors.When the basic methods are used to identify the formation water,the formation water containing anions such as CO_(3)^(2-),OH-and NO_(3)^(-),or the formation water with the sodium chloride coefficient and desulphurization coefficient not matching the geological setting,are all invaded with surface water or polluted by working fluid.When the comprehensive method is used,the data credibility of A-Ⅰ,A-Ⅱ,B-Ⅰ and B-Ⅱ formation water can be evaluated effectively and accurately only if the geological setting analysis in respect of the factors such as formation environment,sampling conditions,condensate water,acid fluid,leaching of ancient weathering crust,and ancient atmospheric fresh water,is combined,although such formation water is believed with high credibility.

关 键 词：油气田水文地质 地层水 水化学数据 可信度评价方法 水化学特征指标 影响因素 

分 类 号：TE122.1[石油与天然气工程—油气勘探]