8 results about "Apparent conductivity" patented technology

The present invention discloses a method for determining the degree of shale lamination development based on electrical imaging data, comprising the following steps: 1: acquiring electrical imaging data from a shale well and processing it to obtain dynamic imaging apparent conductivity data corresponding to each depth point; 2: eliminating abnormal data points; 3: dividing the dynamic imaging apparent conductivity data at each depth point into data segments and calculating the single-point arithmetic mean of each data segment; 4: calculating the overall average of all depth points within any depth range; 5: setting the apparent conductivity fluctuation rate and determining the apparent conductivity fluctuation rate based on the relationship between the single-point arithmetic mean and the overall average of two adjacent depth points; 6: calculating the apparent conductivity difference; 7: calculating the lamination development index; and 8: determining the degree of lamination development. This method also has an improved recognition effect for fine shale laminations and laminations with poor clarity. It is simple to operate, has good recognition effect, fast recognition speed, high response, and strong replicability, and has good universality and promotion value.

The invention provides a method and a device for determining the position of a near-well lamellar low-resistance body, which are used for determining the position parameters of the near-well lamellar low-resistance body by establishing an orthogonal coil system to measure the distribution of an electromagnetic field in a well. The method comprises the following steps: collecting first apparent conductivity of all depths and all preset directions; according to the first apparent conductivity, determining the depth of the thin-layer-shaped low-resistance body beside the well; based on the first apparent conductivity, obtaining the orientation of the thin-layer-shaped low-resistance body beside the well; when the thin-layer-shaped low-resistance body is located in the 0-degree direction and the intersection point of the thin-layer-shaped low-resistance body and the well axis is located in the middle point of the receiving and transmitting coil, second apparent conductivity, measured by all the receiving coils, in all the preset directions is obtained; based on the second apparent conductivity data, obtaining an inclination angle of the well-side lamellar low-resistance body; according to the position relation between the instrument coordinate system and the stratum coordinate system, the position of the well-side thin-layer-shaped low-resistance body in the stratum coordinate system is determined based on the depth of the well-side thin-layer-shaped low-resistance body, the orientation of the well-side thin-layer-shaped low-resistance body and the dip angle of the well-side thin-layer-shaped low-resistance body.

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.

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 propaga

The invention relates to a magnetic phase gradient-based apparent conductivity rapid imaging method and application thereof, and the method combines the recognition capability of a magnetic phase and an electromagnetic field gradient to an underground electrical structure, takes the phase gradient of a magnetic field Hz component as an imaging parameter for imaging, and avoids the error interference of magnetic field multi-component collection. The method can be applied to rapid imaging of the underground electrical structure; particularly, the conductivity is far greater than that of a metal mine area with dielectric loss. Compared with a traditional apparent resistivity imaging method, imaging is carried out through the phase gradient of the Hz component of the magnetic field, high adaptability is shown in different burial depths, electrical characteristics and noise environments, background field correction is not needed in the imaging process, the adverse effect of background resistivity calculation errors on the imaging result is avoided, and the imaging accuracy is improved. And meanwhile, the calculation process is simplified, the complexity of the imaging process is reduced, and the working efficiency and practicability of the method are effectively improved.