徐家围子断陷火成岩裂缝性地层的测井特征与识别

Features and identification of fractured igneous reservoirs on well logging data: A case study at Xujiaweizi Fault Depression

1. 吉林大学,吉林长春 130026;2. 吉林建设工程学院,吉林长春 130026;3. 大庆石油勘探开发研究院,黑龙江大庆 163412;4. 大庆测井公司,黑龙江大庆 163712

Jilin University, Changchun 130026, China

通过与成像测井提供的裂缝信息的对比,给出了火成岩裂缝性地层的测井曲线特征,并以此为基础讨论了根据测井曲线形态来识别火成岩裂缝性地层的方法。通过对测井曲线功率谱的分析,计算了与裂缝发育有关的分维值,并利用分维值来识别裂缝发育层段。针对采用功率谱不能连续对测井曲线进行处理的问题,提出了利用嵌入空间法来连续提取测井曲线的分维曲线。因为测井曲线是岩性和裂缝等因素的综合反映,故采用了多点平滑滤波的处理措施,得到的剩余变化曲线消除了火成岩岩性的影响,在此基础上提取分维值,提高了对裂缝发育带识别的可靠性。最后,给出了识别徐家围子断陷深部火成岩裂缝性地层的应用实例。

We describe the log features of igneous reser-voirs and discusse the identification method of frac-tured zones based on the fracture information fromimage logs. By analyzing power spectra of logs andcalculating fractal dimension the fractured zones canbe identified. In order to eliminate the effect of li-thology on the identification reliability, fractal di-mension is calculated on residual logs. The methodof embedded space is used to extract the fractal di-mention continuously since power spectrum cannotbe generated continuously from log curves. A realdata example is given in this paper.