埋地非金属管道雷达探测成像定位方法研究

非金属管道在地下管网建设中得到广泛应用。探地雷达法作为地下公共设施主要检测方法之一,常被用于地下非金属管线探测中。由于探测过程中存在非金属管道回波信号微弱、地下结构复杂、波速难以精确估算等问题,使雷达探测成像及定位成为难题。针对上述问题,研究了适用于埋地非金属管道的波速估算和回波信号处理方法,提出了空间频域插值成像和二值化定位算法;通过数值仿真验证了所述成像定位方法的可行性,并进行了0.400、0.600和1.100 m埋深的非金属管道现场测试。实验结果表明,所提方法能够有效消除双曲线效应,探测区域的成像定位误差分别为0.006、0.006和0.012 m,满足埋地非金属管道定位需求。研究成果可为埋地非金属管道成像及定位提供技术支持,有益于提高探地雷达对地下非金属管线的探测精度。

Porosity Estimation from Compressional Wave Velocity： A Study Based on Egyptian Carbonate Samples

The porosity of a rock is one of the most important reservoir properties. It controls the reservoir storage capacity. In other words, porosity quantifies the amount of fluids that the rock can store. Most of the world＇s giant fields produce hydrocarbons from carbonate reservoirs. Carbonate rocks contain more than 50% of the world＇s hydrocarbon reserves. Porosity and compressional wave velocity of 41 carbonate samples were determined under ambient conditions in laboratory. The samples were collected from seven shallow wells in west Tushka area, south Western Desert, Egypt. This paper evaluates the well known Wyllie and Raymer equations, an empirical linear equation, and a generalized model for porosity estimation from compressional wave velocity of saturated carbonate samples. Based on the comparison of the predicting identified to provide the most reliable porosity estimation. qualities, the Raymer equation and the empirical linear equation were