摘要
水淹层测井评价的室内实验、理论模拟与实际应用等方面的研究存在某些不一致性。着重对大庆油田目前水淹机理研究和水淹层测井解释中比较突出的问题进行了理论思考和分析,以期对水淹机理实验与生产应用的矛盾作出进一步的解释探讨。在岩心水驱油实验机理研究方面,通过分析原始水和注入水对电阻率贡献的变化,重点阐述了淡水驱替过程中岩心电阻率的"S"形变化规律。综合分析水淹机理实验规律、密闭取心分析以及实际电测资料认为,在污水回注的注水条件下,大庆喇萨杏油田萨、葡、高油层水淹层电阻率呈逐渐降低的趋势。通过对岩心分析不同水洗级别下氯化盐含量下降规律的统计,总结了影响水驱油田水淹层地层水电阻率变化的因素,并指出混合液对地层岩石中氯化盐的溶解作用不容忽视。成藏动力条件的差异是造成油层电阻率高低的主要因素,也是导致在不同孔隙中束缚水分布不同的主要原因,在储层物性相近的条件下,随着束缚水饱和度的增大,油层电阻率逐渐降低。亲水性岩石的微观驱替机理可以看作成藏过程的逆过程,其水驱电性响应规律可以通过岩电参数实验中电阻增大率的变化来反映,在宏观上反映出,物性好的油层含水率曲线具有缓慢上升的阶段,物性差的油层则呈急剧上升的特点。
In recent years,water-flooded layer log evaluation has been one of the key technologies in the middle and late stages of water-flooded oilfields and great progresses have been made in laboratory experiments,theoretical modeling,practical application,etc.But the results of researches on different aspects have certain inconsistencies.In this article,the author analyzed some prominent issues in the current research on water-flooded mechanism and log interpretation of water-flooded layer,and intended to give some explanations and discussions on the contradiction between water-flooded mechanism experiments and the practical application.In the experiments of water-flooded mechanism,the author explicated the S change regularity of the resistivity of core in the course of fresh water displacement process,through the analysis of different contributions of connate water and injected water.After multidisciplinary analysis on the regulation of water-flooded mechanism experiments,sealed core data analysis and practical electrical logging data,the author concluded that the resistivity of water-flooded layer presents the tendency of declination in Daqing Lasaxing oilfield under the current condition of produced water re-injection.Through core data statistics of the declination rules of chlorate at different water flushed levels,the author summed up influential factors on the resistivity variance of water-flooded layers in water-flooded fields,and pointed it out that the dissolution of mixed fluid to chlorate should not be overlooked.The main factor which causes reservoir resistivity high or low is the difference of accumulation dynamics condition,which also is the main reason causing distribution of irreducible water in different pore types.Under the similar condition of reservoir physical property,the reservoir resistivity declines gradually with the increasing of irreducible water saturation.The microcosmic displacement mechanism of water wet rock can be considered as the reverse process of reservoir accumulation.The law of water-drive electric property can be got from the changes of the resistivity rate in rock electrical parameters experiments.In macro level,water cut plot of reservoir with good physical property presents the characteristic of slowly rising period,while that of poor reservoir shows steep rise.
出处
《测井技术》
CAS
CSCD
北大核心
2009年第6期511-516,共6页
Well Logging Technology
关键词
测井解释
水淹机理
水淹层
地层水电阻率
成藏动力
束缚水饱和度
亲水性油层
log interpretation
water-flooded mechanism
water-flooded layer
formation water resistivity
accumulation dynamics
irreducible water saturation
water wet reservoir log interpretation
water-flooded mechanism
water-flooded layer
formation water resistivity
accumulation dynamics
irreducible water saturation
water wet reservoir log interpretation
water-flooded mechanism
water-flooded layer
formation water resistivity
accumulation dynamics
irreducible water saturation
water wet reservoir
