固井质量评价仪在井周不同岩性的响应分析

Response Analysis of Different Circumference Lithologyies with Cementing Quality Assessment Instrument

通过刻度井群中的1、2号模拟井分别进行CBL-VDL、SGDT-MAK-Ⅱ和SBT固井质量测井实验,模拟水泥固结良好时井周不同地层模块的情况。通过对这些测井数据与1、2号井井周不同岩性对比分析,总结出在水泥固结好时,声幅受地层岩性影响较小,VDL受地层岩性影响比较大;当Ⅰ界面固结好时,快速地层波与套管波可能会叠加,使CBL值增大,在定量评价时对不同的岩性剖面应采用不同的评价标准;当Ⅰ界面固结不好时,受Ⅱ界面胶结程度影响,在快速地层有时可能观察到地层波。在用SGDT和SBT评价固井质量时因受地层岩性影响较大,应根据不同岩性进行相应的校正。

The CBL-VDL, SGDT MAK II and SBT log tests about cementing quality are made respectively in the No. 1 and No. 2 simulated wells in scale well group to estimate influence of lithologies on these logs when the cementing quality is better. Comparison between these log data and different circumference lithologies in the No. 1 and No. 2 wells indicates that when the cementing quality is better, the CBL is less influenced by the lithology; VDL is much influenced by the lithology; When cementing quality of boundary-I is better, fast formation wave and casing wave may stagk, which makes CBL value increase, so different evaluation standards should be used for different lithology profiles when making quantitative evaluations; When the cementing quality of boundary-I is not good, the formation wave may be found in fast formation due to boundary- Ⅱ cementing influence. Different lithologies should be correspondingly corrected because SGDT and SBT logs are much influenced by the lithologies in cementing quality evaluations.