复电阻率测井仪中信号检测算法的研究

现代油田电测井法技术,通常只能测量井下地层电阻率值而不能测量地层相位差信息,因而影响了对地层含油饱和度的评估。复电阻率相位检测技术是目前复电阻率测井技术的一个主要的发展方向。本系统对经过地层的测试电压和电流信号进行采集及检测,并且将检测的信号经数字化处理后,从而获得地层复电阻率值。测量结果反映了在不同频率的地层测试信号下地层含油饱和度的情况,弥补了常规含油饱和度测井系列的不足。重点介绍了改进的检测复电阻率测井中信号相位差和幅度等参数的测量方法,并详细分析了影响测量精度的主要因素。在此基础上实现了数字化的复电阻率检测系统。

Algorithm Research of Signal Processing in Complex Resistivity Logging Tool

Modern oil-field electrical logging technique,usually only can be used to measure resistivity of underground strata,but stratigraphic phase shift information can't be measured,thereby the stratigraphic oil saturation assessment is affected.Complex resistivity phase detection is one of the development trend of complex resistivity logging technology.A stratigraphic test voltage and current signal acquisition and detection could be done in this system of logging.The tested data are processed in DSP(digital signal processor),and then the value of stratigraphic complex resistivity could be figured out.The oil saturation is indicated by measurement results in different frequency,which compensate the lack of traditional oil saturation logging.The improved correlation method of complex resistivity logging in phase and amplitude parameters detection is discussed and the main factors that effect on measuring accuracy are also analyzed in detailed.Based on this theory,a draft designing of digital complex resistivity measurement system is implemented.