摘要
针对套管井阵列声波测井的工程需要,用实轴积分法及二维谱技术研究了不同胶结状况的二维谱及频散曲线。从理论上肯定了对于快速地层,胶结状况良好和第Ⅰ界面窜槽不严重时在套管井内能够测量到地层的纵、横波时差。描述第Ⅰ界面窜槽的等效水环厚度增加,以地层的纵、横波速度传播的声波时差分布不再集中,直到最后消失。第Ⅱ界面脱粘时无法测量到地层的纵、横波时差。根据上述理论计算结果设计了阵列声波测井仪器,用多口套管井的实际测量波形和处理结果肯定了上述理论分析,得到了地层的纵、横波时差。这样,对于套管井,除了能够测量地层的纵、横波时差外,从固井质量评价上,第Ⅰ界面胶结质量的判别方法还可以使用相位信息,即用阵列波形的相位建立模型,得到地层纵波时差分布,该分布越离散,则第Ⅰ界面胶结的程度越差;当集中不起来,不能够显示地层的纵波时差时,则第Ⅰ界面窜槽已经相当严重。
Aimed at the engineering requirement of array sonic logging in cased hole, the real axis integration and 2-dimensional spectrum method are used to calculate 2-dimensional spectra and dispersion curves in different bonding conditions. For fast formation, the theoretical analysis affirmed that S and P wave slowness of formation can be measured if the cased hole is in good cemented condition and no serious channel in casing-cement interface; when thickness of an equivalent water annulus simulating the casing-cement interface channeling is increased, sonic slowness distribution of P and S wave of formation is gradually dispersed and finally disappeared; and if the cement-formation interface is adhesive failure, the slowness of P and S wave of formation will not be able to be measured. Based on abovementioned theoretical analysis, an array sonic logging tool is designed, its waveforms measured practically in several cased holes and their processing results have affirmed the theoretical analysis, and sonic slownesses of P and S wave of formation have been obtained. It implies that the dispersing of slowness distribution of P wave could also be used to distinguish cementation quality of casing-cement interface.
出处
《测井技术》
CAS
CSCD
2007年第2期128-134,共7页
Well Logging Technology
关键词
生产测井
套管井
阵列声波测井
实轴积分法
二维谱
时差
production logging
cased hole
array sonic logging
real axis integration
2-dimensional spectrum
slowness
