摘要
在岩性密度测井仪中使用的两能窗稳谱技术存在稳谱耗时长、效果不稳定,特别是在低密度岩层易使高压值跟踪在伪平衡点上等问题。四能窗稳谱处理技术使用线性近似基线谱校正本底或Compton散射伽马等对稳谱窗计数的影响;采用自适应递归数字时间延迟滤波,并根据纵向分辨率和测速的要求,通过测井实践得出了比较合理的稳谱调度周期和帧数;构建了合适的稳谱状态因子与高压调节增量之间的函数关系,克服了两能窗稳谱技术存在的不足。实际应用表明该技术原理正确,实施方法可行、有效。
2-window spectrum stabilization method in litho-density logging tool has some problems, such as too much long time being spent in spectrum stabilizing process, not so good stabilization effect, especially, the high voltage tracing false equilibrium point in low density layers. These problems are overcame by a 4-windows spectrum stabilization method, in which linear approximation baseline spectrum is used to correct effects of background and Compton scattering gamma to counts in spectrum stabilization windows; adaptive recursion time-delayed digital filter is utilized and reasonable operational period and number of frames for spectrum stabilization are extracted through practical loggings according to requirements of vertical resolution and logging speed; and satisfactory functional relation between status factor of spectrum stabilization and increment of high voltage adjusting. Practical applications of the method show that its principle is correct and its implementation is feasible and effective.
出处
《测井技术》
CAS
CSCD
2008年第1期76-79,共4页
Well Logging Technology
关键词
岩性密度测井仪
能窗
稳谱
高压
litho-density logging tool, energy window, spectrum stabilization, high voltage
