摘要
鄂尔多斯盆地西南部侏罗系低阻油层的广泛分布,油、水层测井识别存在困难,在一定程度上制约了该地区勘探、开发的高效推进.本次研究针对该地区低阻油层成因进行了分析,并在明确主控因素的基础上提出了相适应的油、水层识别方法,旨在为该地区勘探、开发提供技术保障.本文从合道地区侏罗系基础地质规律出发,充分利用试油结论、试采动态、地层水分析等资料,对该地区低阻油层成因进行分析.认为造成该区域普遍发育低阻油层的主要控制因素为高地层水矿化度,束缚水饱和度、鼻隆构造幅度属于次要因素,其差异也在一定程度上影响了储层视电阻率.对于整体区域而言,受控于基础地质特征的诸多差异,利用储层声波时差与视电阻率交会图等常规图版,已无法对油、水层进行有效识别.结合低阻油层成因,在整体区域范围内,利用地层水矿化度与储层视电阻率建立交会图,油、水层识别精度得到提升.考虑到钻井液侵入作用进一步降低了测井对比度,引入视电阻增大率与地层水矿化度构建油、水层识别图版,识别精度进一步提高.通过具体区块实例验证,该方法对于低阻油层具有良好的识别效果.此外,该方法能够反应出储层视电阻增大率随地层水矿化度的变化规律,在满足油、水层定量识别精度要求的基础上,具有一定的地质意义.
It is difficult to identify oil and water layers by conventional logging because of the wide distribution of Jurassic low resistivity reservoirs in the southwest of Ordos basin,which restricts the exploration and development of this area to a certain extent.Aiming at providing technical support for exploration and development in this area,this study analyzes the genesis of low resistivity oil reservoir in this area,and puts forward corresponding identification methods of oil and water layers on the basis of clarifying the main control factors.Based on the basic geological law of Jurassic in Hedao area,this paper makes full use of the data of oil test,production test,and formation water analysis to make a analysis of the genesis of low resistivity oil reservoir in this area.It is considered that the main controlling factors for the development of low resistivity reservoirs in this area is the high salinity of formation water.The irreducible water saturation and the structural amplitude of nose structures are secondary factors whose differences also affect the apparent resistivity of the reservoir to a certain extent.For the whole area,controlled by many differences in basic geological characteristics,it is impossible to effectively identify oil and water layers by using conventional charts such as crossplot of acoustic moveout and apparent resistivity of reservoir.In the whole stduy area,combined with the genesis of low resistivity reservoir,the cross plot is established by using the salinity of formation water and the apparent resistivity of reservoir,and the identification accuracy of oil and water layers is improved.Considering that the invasion of drilling fluid further reduces the logging contrast,the apparent resistivity increase rate and formation water salinity are introduced to build the oil and water layer identification chart,and the identification accuracy is further improved.Through the verification of specific block examples,this method has good recognition effect for low resistivity reservoir.In add
作者
郭京哲
李娅
韩斌虎
张攀
GUO JingZhe;LI Ya;HAN BinHu;ZHANG Pan(Department of Geology,Northwest University,Xi'an 710069,China;State Key Laboratory for Continental Dynamics,Northwest University,Xi'an 710069,China;Exploration and Development Research Institute of PetroChina Changqing Oil Field Company Limited,Xi'an 710018,China;National Engineering Laboratory for Exploration and Development of LowPermeability Oil and Gas Fields,Xi'an 710018,China;No.11 Oil Production Plant of PetroChina Changqing Oil Field Company Limited,Qingyang 745000,China)
出处
《地球物理学进展》
CSCD
北大核心
2022年第6期2381-2394,共14页
Progress in Geophysics
基金
国家科技重大专项“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程”(2016ZX05050)资助。
关键词
鄂尔多斯盆地
侏罗系
低阻油层
地层水矿化度
视电阻增大率
Ordos basin
Jurassic
Low resistivity reservoir
Formation water salinity
Apparent resistivity increasing rate
