【作者】 程相志；

【导师】 范宜仁；

【作者基本信息】 中国石油大学 ， 地质资源与地质工程， 2008， 博士

【摘要】 低阻油气层作为一种特殊的、隐蔽性极强的油气层,具有巨大的勘探潜力,但由于其复杂的地质成因和形成条件,导致其识别评价具有极大的难度。针对低阻油气层识别评价困难的问题,论文通过对大量岩石实验结果的分析和典型低阻油气层测井响应特征的整理与分析,系统总结了形成低阻油气层的内因和外因,内因主要有高不动水和高阳离子交换量,外因主要有泥浆侵入、砂泥岩薄互层及油水层矿化度的差异等,每一种成因都对应着独特的地质条件。对于某一地区而言,这些成因都是广泛存在的,而且往往是以一两种为主控因素的多因素共同影响着油气层的电阻率。所以,文中提出了基于主控成因的低阻油气层识别评价思路,针对不同成因低阻油气层提出了低阻油气层测井系列和测井环境设计思想及原则,在此前提下创建了基于主控成因分析的、利用常规测井资料识别低阻油气层的多种新方法,这些方法主要有:①首次提出了泥浆性能优化设计下利用自然电位信息识别低阻油气层的方法技术,即咸水泥浆条件下的油气层自然电位为小幅度的正异常或负异常;②创建了多种综合参数交会图油水层识别图版,图版制作过程中,每一个坐标向量的选取都首先考虑了影响储层电阻降低的岩性、水性、泥浆等因素,通过多种测井信息的有效融合将这些影响因素由综合参数体现出来,并且放大油层与水层之间的差异,通过综合参数的两两交会达到低阻油气层识别的目的;③针对岩性细、孔隙结构复杂、水性变化导致的低阻油气层,建立了模型参数m、n与泥质含量、孔隙结构指数和地层水电阻率之间的经验公式,通过低阻主控成因在模型参数中的体现来应用阿尔奇模型计算低阻油气层饱和度,这是对阿尔奇模型的发展和完善;④针对高阳离子交换量低阻油气层,提出W-S模型在低阻油层评价中的实用化思路和实现方法,依据多温度、多矿化度下的岩石电阻率实验结果,建立了W-S模型参数Bws与温度和地层水电阻率的实验关系,采用激发极化测井资料计算储层阳离子交换量和地层水电阻率,由此可以实现了W-S模型的推广应用;⑤论文还提出了测井与地质相结合的低阻油气层判别原则:即分层位、细分解释单元、合理的地层对比。低阻油气层识别评价思路和技术在冀东滩海油田得到了有效的推广和深化应用,而且在勘探和储量落实过程中发挥了非常重要作用。更多还原

【Abstract】 As strongly subtle and special oil and gas reservoir, the low-resistivity pay has enormous exploration potentiality. But because of its complex geologic genesis, the low-resistivity pay is very difficult to indentify and evaluate. Aimed at the question of indentifying and evaluating the low-resistivity pay, this paper systematically summarizes the internal genesis and external genesis of low-resistivity pay by analysising the results of enough rock experiments and collecting the log response of typical low-resistivity pay. The internal genesis mainly include high bound water and high cation exchange capacity, and the main external genesis are mud invasion, sand shale sequence and different water salinity in oil/water layers, each kind of genesis is link to the peculiar geologic condition. To a certain area, the genesis are wildly existed, but only one or two is the major genesis which effect the resistivity of oil and gas layers. Therefore, it is developed that the approach and scheme of identifying and evaluating the low-resistivity pay based on the major genesis, the design concept and principle of log system and environment are established, and many new methods based on the major genesis and conventional logging data are proposed. Those new methods are as follows:①A new technique of recognizing low-resistivity pay by SP is first proposed, it is based on optimizing design of drilling-mud property,.oil reservoir has low amplitude positive or negative SP anomaly under brine mud.②The axis of crossplots of identifying oil layers represents integrated parameters, on this parameters, lithology, salinity and mud are considered. This parameters enlarged micro-difference between oil and water layers, two of this parameters are used to identify low-resistivity pay.③According to the difference on the main genesis, this paper develops and improves Archie’s Model. Aimed at low-resistivity pay due to fine lithology, complex pore structure and the changed salinity, this paper has established empirical formula between parameters in the model (m, n) and shale content, porous structure exponent, formation water resistivity. Archie’s Model is used to calculate saturation of low-resistivity pay by considering main control factors into model parameters.④This paper supplements and popularizes W-S Model. According to low-resistivity pay with higher cation exchange capacity, this paper establishes the relationship between Bws and temperature based on the experiment results of rock resistivity in various temperature, and calculates cation exchange capacity and water resistivity by induced polarization log data. So W-S Model can be applied.⑤This paper has also proposed an identification principle combined well-logging and geology: stratigraphic position separation, fine division of interpretation unit and reasonable stratigraphic correlation.⑥New well technology plays an effective role in recognition of low-resistivity pay. In a word, the idea and technology of identification and evaluation on low resistivity pay are effectively popularized and applied in Jidong Oil Field, and they have played an important role in exploration and reserve confirmation.更多还原