梨树断陷七棵树地区油田水水化学特征及成因分析  

Characterization and genesis of oilfield water hydrochemistry in the Qikeshu,Lishu Fault

作　　者：王聪毅 WANG Congyi(Beijing Institute of Geological Hazard Prevention,Beijing 100120,China)

机构地区：[1]北京市地质灾害防治研究所,北京100120

出　　处：《城市地质》2024年第4期500-507,共8页Urban Geology

基　　金：国家自然科学基金项目(41272170)资助。

摘　　要：为查明七棵树地区油田水水化学特征及其离子来源,在研究区采集了10组油田水样品,综合采用了描述性统计、Piper三线图法、Gibbs图法、相关性分析、D函数规律分析等方法对样品测试结果进行了分析。结果表明:七棵树地区油田水水化学类型主要为低SO_(4)^(2-)、低HCO_(3)^(-)的Cl^(-)Na·K型水和低SO_(4)^(2-)、低Cl^(-)的HCO_(3)^(-)Na·K型水;油田水水化学特征主要受蒸发结晶作用的影响,在演化过程中水体主要受大气降水补给,油藏储存环境封闭性较差;离子相关性分析结果显示,TDS与Na^(+)+K^(+)和Cl^(-)均具有很强的正相关性(R=1,P<0.01),验证了Na^(+)+K^(+)和Cl^(-)是决定油田水盐化的主要变量;D函数规律表明,七棵树地区油田水的形成是由于阳离子分异显著所致,符合阳型油田水的特征,分异现象主要与油田水形成的蒸发结晶作用、阳离子交换作用有关。In order to identify the chemical characteristics and ion sources of oilfield water in the Qikeshu area,10 sets of oilfield water samples were collected in the study area,and comprehensive analyses were carried out through descriptive statistics method,Piper three-line diagram method,Gibbs plot method,D-function analysis and so on.The research results indicate that the main types of oilfield water chemistry in the Qikeshu area are mainly Cl^(-)Na·K water with low SO_(4)^(2-)and low HCO_(3)^(-)and HCO_(3)^(-)Na·K water with low SO_(4)^(2-)and low Cl^(-).The hydrochemical characteristics of oilfield water are mainly affected by evaporation and crystallization,and the water body is mainly recharged by atmospheric precipitation during the evolution process,and the reservoir storage environment is poorly closed.The results of ionic correlation analysis show that TDS has a strong positive correlation with both Na^(+)+K^(+)and Cl^(-)(R=1,P<0.01),which verifies that Na^(+)+K^(+)and Cl^(-)are the main variables determining the salinization of oilfield water.The D-function law indicates that the formation of oilfield water in the Qikeshu area is due to cation differentiation,which is consistent with the characteristics of cationic oilfield water.And the differentiation phenomenon is mainly related to the evaporation and crystallization effect and cation exchange effect of oilfield water formation.

关 键 词：七棵树地区 油田水 水化学特征 D函数 

分 类 号：P641[天文地球—地质矿产勘探] P618.13[天文地球—地质学] TE14[石油与天然气工程—油气勘探]