Study on Washing Laws and Remaining Oil Characteristics of Sealed Coring Wells in X Oilfield

会议论文
发表日期：

2026年

查看全文

Shuai Wang,
Fei-fei Zhang,
Peng-kun Liu,
Dong-mei Cai,
Xian-di Fu,
Hui-dong Yang,
Li Si,
Shu Yan,
Guo-hong Sun,
Jian-hua Xiao,
Li-Ying Yang,
Sheng-nan Hu,
Yang Wang

摘要

There are a large number of sealed coring wells, with wild distribution in X Oilfield, but there is a lack of systematic research on core data. The article applies the results of core observation and description of 25 sealed coring wells in X Oilfield in different periods, along with experimental results such as permeability pore saturation, and combined with fine reservoir depiction results of dense well network, to quantitatively analyze the washing laws and residual oil distribution characteristics of oil layers at different development stages in terms of oil layer types and displacement methods, The results show that: The use of chemical flooding in class I and class II oil layer has significantly improved the oil displacement efficiency. The oil displacement efficiency of class I oil layer is 62.8% after ASP flooding, which is 7.9% higher than after polymer flooding and 11.5% higher than after water flooding. The oil displacement efficiency of class II oil layer is 60.1% after ASP flooding, which is 6.4% higher than after polymer flooding and 13.7% higher than after water flooding. After water flooding and chemical flooding in class I and class II oil layer, the proportion of remaining oil thickness in moderately weakly washed and below accounts for 22.4% and 40.5%, respectively. After water flooding in class III oil layer, the proportion accounts for 51.1%.After chemical flooding, the remaining oil in class I oil layer is mainly in form of interlayer interference and interlayer shielding; in class II oil layer, the remaining oil is mainly enriched in sedimentary face transitions, diversion lines, and fault edges; in class III oil layer, the remaining oil is mainly type of interlayer interference and poor physical property. The potential for residual oil in different types of oil layers remains huge. It has made great improvements in tailored tapping countermeasures for residual oil based on types of oil layer and residual oil.