摘要
分析研究表明,快速地层水泥完全胶结时的地层波与套管波的主频差别较大,套管波主频明显偏高。通过在频域内计算套管波能量,可有效消除快速地层对固井Ⅰ界面胶结质量评价的影响。另外,结合现场变密度测井资料研究发现,地层波能量不仅反映固井Ⅱ界面胶结情况且受地层声速的严重影响,Ⅰ、Ⅱ界面水泥完全胶结时地层波能量和声波时差存在一定的指数关系。考虑地层声速的影响,可定义出主要反映水泥胶结质量的Ⅱ界面胶结指数。给出了快速地层和复杂岩性地层的现场变密度资料的处理实例,处理结果表明,通过计算套管波能量和定义Ⅱ界面胶结指数基本消除了地层声速对固井Ⅰ、Ⅱ界面胶结质量评价的影响。
The results obtained indicate that the center frequency of cased wave is obviously higher than that of formation wave in fast formation. The effects of fast formation on first interface evaluation can be effectively eliminated by calculating cased wave energy in frequency domain. In addition, based on field VDL data, it is found that formation wave energy that actually reflects the cement quality of second interface is affected by formation velocity. When the cement of first and second interface bonds well, there exists exponential relationship between formation wave energy and slowness. Considering the effects of formation velocity on formation wave energy, a bond index of second interface that mainly reflects the cement bond quality is defined. Examples of processing fast formation and complicated lithology formation with field VDL data are offered in this paper. The processed results show that basically the influence of formation velocity on the bond quality of first and second interface is eliminated.
出处
《石油钻探技术》
CAS
北大核心
2005年第4期39-41,共3页
Petroleum Drilling Techniques
关键词
固井质量
声波时差
声波全波列测井
cementing quality
interval transit time
full wavetrain acoustic logging
