过套管测井技术在南海西部油田油气藏综合评价中的应用

过套管测井是指在探井或开发井已经下入套管固井后的井段进行套管内测井作业，并在此基础上进行油气层识别、储层物性评价、水淹层评价等研究。早期，过套管测井主要应用在开发测井中进行油藏动态监测、剩余油分布监测、井区水驱效果、水淹层分析等方面，其方便实用的特点使其在油田生产中得到广泛应用。近些年，由于大斜度井、水平井、高温高压等高风险复杂结构井逐渐增多，裸眼测井面临无法录取资料的风险。为了降低测井作业事故发生概率，取全测井资料，缩短作业周期，可以利用过套管测井代替原有的裸眼测井。但对于过套管测井，由于套管的隔离作用以及井眼和地层等影响因素，相较于裸眼测井其探测范围更小，油气藏评价结果存在疑问。通过对过套管电阻率、中子、密度测井原理进行分析，厘清过套管测井响应的影响因素并进行相应的校正处理，结合同井眼裸眼随钻测井以及邻井同层位测井资料对比，验证了过套管测井资料的可靠性。在此基础上再进行油气藏综合解释，有效解决了过套管测井评价技术的难点。

The Application of the Through Casing Logging Technology in Comprehensive Evaluation of Oil and Gas Reservoir in Western South China Sea

Through casing logging refers to the research on reservoir identification, reservoir physical property evaluation and water-flooded zone evaluation on the basis of the casing well survey in the exploration well or development well after casing cementing. In the early stage, casing-through logging is mainly used in reservoir dynamic monitoring, remaining oil distribution monitoring, well area water flooding effect, water-flooded zone analysis and other aspects in the development logging. Because of its convenient and practical characteristics, it is widely used in oilfield production. In recent years, due to the increasing number of highly deviated wells, horizontal wells, high temperature and high pressure and other high-risk complex structure exploration wells, in order to reduce the probability of logging operations and shorten the logging period, casing-through logging can be used to replace the original open hole logging.It is worth noting that for cased hole logging, due to the isolation of casing and the influence of borehole and formation, the detection range is smaller than that of open hole logging, and the evaluation results of oil and gas reservoirs are in doubt.Through the analysis of the logging principles of casing through resistivity , neutron and density , the influencing factors of casing through logging response are clarified and the corresponding correction processing is carried out. On this basis, the comprehensive interpretation of the reservoir is carried out, which effectively solves the difficulty of casing through logging evaluation technology.