【作者】 宋殿光；

【导师】 张贵宾；

【作者基本信息】 中国地质大学（北京） ， 地球探测与信息技术， 2014， 博士

【摘要】 随钻测井技术现已成为油田开发获得最大效益的至关重要手段，在国内外油田应用非常普遍。随钻电磁波测井仪器是随钻测井仪器的核心之一，在地层评价和地质导向方面被广泛应用，但少见该类仪器在地质导向应用中的系统理论研究，因而，本文基于正反演数值模拟，对随钻电磁波仪器的地质导向应用进行了详细研究。正演数值模拟主要采用磁偶极子源并矢格林函数理论，利用矩阵递推原理推导出各向异性任意多层介质中的并矢格林函数。该方法适用于分析线圈任意方向放置的随钻电磁波测井仪器的响应，具有计算速度快，精度高的优点。反演中开发了自适应阻尼型高斯牛顿和变形波恩迭代方法，并给出一种新的正则化方法以及不等式约束条件施加方法。利用开发的正反演方法模拟了常规及倾斜线圈随钻电磁波测井仪在大斜度井中的响应规律和在地质导向中的应用。模拟结果表明，常规电磁波测井仪在大斜度井中靠近地层边界时，响应有极化角现象可作为预示界面存在的依据，受各向异性的影响随相对倾角的增大而增大，薄互层呈现出宏观各向异性特征。新一代单发单收倾斜线圈采用更低的频率和更长的源距，在靠近地层上下界面时分别呈现相反的信号特征，能有效识别界面方向。对双发双收倾斜线圈结构定义了一种新的定向信号，使该结构形式同时具备地层评价和地质导向方位探测能力。模拟结果表明，电阻率响应受各向异性的影响更加敏感，而定向测量则基本不受影响，对界面的响应特征与单发单收线圈结构相同。对地质导向矢量角理论进行了研究，利用空间重叠算法进行数值模拟，发现该矢量角始终指向电导率更大的方向，与倾斜线圈的定向信号结合可以判断仪器从哪个方向靠近边界，该理论适用于地层界面不平行的情况。采用多种地层模型，对随钻电磁波仪器进行了反演数值模拟。提出了一种多初值法，通过模拟发现，该方法可以有效改善由于初值给定不合适引起的迭代发散以及多解性问题。总结了相对倾角及地层电阻率参数误差对反演结果的影响规律，验证了地质导向反演中三层模型的可行性。在具有多个薄层的地层模型下，常规电磁波电阻率曲线比深探测定向曲线具有更好的界面识别效果，而厚地层中深探测定向测量曲线则具有更好的界面识别效果。更多还原

【Abstract】 Logging-while-drilling (LWD) technology has become a key method for oil field toget the maximum production, and it is worldwide used in the oil fields at home and abroad.Electromagnetic LWD tool is one of the core logging tools which is widely used information evaluation and geosteering. However, very little researches of systematic theoryof such instrument have been carried on. Thus in this thesis, based on forward andinversion numerical simulation, the geosteering applications of electromagnetic tool werestudied detailed.The forward numerical simulation was based on the dyadic Green’s functionproduced by magnetic dipole. The dyadic Green’s function of anisotropy formation withany number of layers was deduced using matrix recursive principle. This method is withhigh calculation speed and high accuracy, and it is suitable for the analysis of the responseof electromagnetic LWD tool with the coils placed in any direction. In the inversionnumerical simulation, adaptive damping Gauss Newton and distort Born iterative method,a new regularization method and inequality constraint imposed method were developed.In this thesis, the response rules and application in geosteering in highly deviatedwells of the electromagnetic LWD tool with conventional and tilted coils were simulatedby using the developed forward and inverse methods. The results showed that in highlydeviated wells, when the conventional electromagnetic LWD tool is near the formationboundary, there is a polarization angle phenomenon of the response which can indicatesexisting of the boundary, and the response is affected by the anisotropy and increases withthe increasing of relative angle. The thin alternating layers showing macroscopicanisotropy. The new generation tool with single transmitter and single receiver with tiltedcoils uses a lower operating frequency and the spacing is longer. When it is near the upperand lower formation boundaries, the response shows opposite signal characteristicsrespectively, and that can effectively help identifying the direction of the boundary. A newdefinition of directional signal was developed in the tool with two transmitters and tworeceivers with tilted coils, so that the tool had the capabilities of formation evaluation aswell as geosteering. The numerical simulation results showed that the resistivitymeasurement is more sensitive to anisotropy than conventional tools’ measrement, while the geosteering direction measurement is not affected, and the boundary responsecharacteristics of two tansmitters two receivers system is same with the single tansmittersingle receiver system. Geosteering vector angle theory was studied using numericalsimulation with space superposition algorithm. The results showed that the vector angle isalways pointing to the direction of greater conductivity. Combined with directional signalsof tilted coils, it can be determined that from which direction the tool is getting close tothe boundary. This theory can apply in the case in which the formation boundary is notparallel.Several formation models were built and the inversion numerical simulations ofelectromagnetic LWD tool were done using these models. A multi-initial method wasintroduced. The results showed that the method can resolve the problems of iterationdivergence and multiple solutions caused by the inappropriate initial value. The influencerule of relative dip and formation resistivity parameter errors were summarized and thefeasibility of the inversion of three layers model was verified. In the models of several thinlayers, the conventional electromagnetic resistivity curve is more effective than the deepdirectional curve in boundary identify, while in the models of thick layers, the deepdirectional curve is more effective.更多还原