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介电测井是评价井下储油层的一种方法。这种方法的依据,即地层的介电特性是随着它含油气和地下水的相对饱和度而变化的。要提高某个地区介电测井的适用性,就要降低理论测井的误差。这里提出了有限误差的四个要求。我们曾经用测井模型研究了它固有的误差(不精确性)。理论测井中提出的可接受的误差是15％或小于15％。第一,目前四极电路发射线圈是用来激发偶极电流的。为了使得四极电路具有可接受的误差水平,测井线圈的直经必须小于井下波长的0.09。第二,我们已经知道,对于接收线来讲,要不影响四极偶合,它取决于线圈的距离。线圈的距离较小,四极偶合的误差也较小。我们得到的一组曲线说明,若选用线圈直经为5厘米,为了获得满意的误差水平,线圈距离必须从225厘米、测井频率15兆赫减小到50厘米、45兆赫。这组曲线用于设
Dielectric logging is a method of evaluating downhole reservoirs. The basis of this approach is that the dielectric properties of the formation vary with the relative saturation of its hydrocarbon and groundwater. To improve the applicability of dielectric logging in a certain area, it is necessary to reduce the theoretical logging error. Here are four requirements for finite error. We have studied its inherent error (inaccuracies) with logging models. Acceptable error in theoretical logs is 15% or less. First, the current quadrupole transmitter coil is used to excite dipole current. In order for the quadrupole circuit to have an acceptable level of error, the straightness of the logging coil must be less than 0.09 of the downhole wavelength. Second, we already know that for the receive line it does not affect the quadrupole coupling, it depends on the distance of the coil. The smaller the coil distance, the smaller the error of the quadrupole coupling. The set of curves we have obtained shows that if the coil is chosen to be 5 centimeters straight, the coil distance must be reduced from 225 centimeters to 15 centimeters down to 50 centimeters at 45 MHz in order to obtain a satisfactory level of error. This set of curves is used for setting