5 results about "Apparent conductivity" patented technology

The present application relates to a kind of based on the apparent conductivity fast imaging method of magnetic phase gradient and its application, the method combines magnetic phase and electromagnetic field gradient identification ability to underground electrical structure, with the phase gradient of magnetic field Hz component as imaging parameter and carries out imaging, avoids the error interference of magnetic field multiple component acquisition.The present application can be applied to the fast imaging of underground electrical structure;Particularly, the metal mine area of conductivity far greater than dielectric loss.Compared with the traditional apparent resistivity imaging method, the present application carries out imaging by the phase gradient of magnetic field Hz component, shows strong adaptability under different burial depth, electrical characteristics and noise environment, without background field correction in imaging process, avoids the adverse effects of background resistivity calculation error on imaging result, while simplifying the calculation process, reduces the complexity of imaging process, effectively improves the working efficiency and practicality of the method.

The invention provides an induction logging skin effect correction method and device and an induction logging device.A subarray is simulated in advance to detect a sample medium, apparent conductivity measured under various working frequencies and corresponding true conductivity are obtained, and the first apparent conductivity under the target frequency is determined according to the apparent conductivity and the corresponding true conductivity; calculating a first relative skin depth according to the first apparent conductivity and the source distance, calculating a ratio of the true conductivity to the first apparent conductivity under the target frequency as a conductivity ratio, and fitting each conductivity ratio with the corresponding first relative skin depth to obtain a skin depth value; obtaining a quantitative relationship among the true conductivity, the first apparent conductivity under the target frequency and the first relative skin depth; during actual well logging, second apparent conductivity and second relative skin depth under the target frequency are calculated on the basis of a method similar to that during simulation detection, and then the measured apparent conductivity is corrected by combining the quantitative relation. The scheme can improve the accuracy and reliability of the correction result.

A method for estimating an apparent conductivity of a subterranean formation includes acquiring at least first and second electromagnetic propagation measurements made using an electromagnetic propagation tool having at least one transmitting antenna spaced apart from at least one receiving antenna. A ratio is computed using the measurements and further evaluated to estimate the apparent conductivity.

The present application belongs to the technical field of induction logging data processing, and discloses an induction logging iterative borehole correction method and device. The data of n sub-arrays under different hole diameters and borehole influence factors are fitted to determine a first formula of the borehole influence factors and the first ratio of the n sub-arrays under different hole diameters. According to the first formula, the coefficients a, b and c of different sub-arrays under different hole diameters are determined. A given initial formation apparent conductivity value is used to calculate the borehole influence factor according to the first formula. The borehole influence factor is brought into a second formula to calculate the formation apparent conductivity. The formation apparent conductivity is brought into the first formula to calculate the borehole influence factor, and the result is brought into the second formula for iterative calculation to obtain the formation conductivity response value not affected by the borehole mud. The present application can be applied in induction logging data inversion and does not have the inversion process, and can obtain the formation conductivity response value not affected by the borehole mud.