CN114233274B

CN114233274B - Image generation method and device based on while-drilling electrical imaging

Info

Publication number: CN114233274B
Application number: CN202210175437.3A
Authority: CN
Inventors: 于增辉; 牛德成; 刘耀伟; 王芝环; 侯洪为; 鲍东升; 张中庆; 刘保银; 邵晓程
Original assignee: China Oilfield Services Ltd
Current assignee: China Oilfield Services Ltd
Priority date: 2022-02-25
Filing date: 2022-02-25
Publication date: 2022-05-10
Anticipated expiration: 2042-02-25
Also published as: CN114233274A

Abstract

The invention discloses an image generation method and device based on while-drilling electrical imaging. The method comprises the following steps: calculating eccentric orientations corresponding to different logging depths according to measured response values of the electrical imaging while drilling; determining eccentricity and formation resistivity corresponding to different logging depths; constructing a first equivalent stratigraphic numerical model under the eccentric environment of the borehole; constructing a second equivalent stratigraphic numerical model under the non-borehole eccentric environment; taking the ratio of a second simulation response value of a second equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth to a first simulation response value of a first equivalent stratigraphic numerical model as an eccentricity correction coefficient; correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value; and generating an electrical imaging while drilling image. According to the scheme, the resolution and the definition of the while-drilling electrical imaging image can be improved, and the stratum analysis precision and the application precision based on the while-drilling electrical imaging image are improved.

Description

Image generation method and device based on while-drilling electrical imaging

Technical Field

The invention relates to the technical field of data processing, in particular to an image generation method and device based on while-drilling electrical imaging.

Background

The logging-while-drilling electrical imaging technology is a logging technology which measures by a logging-while-drilling instrument and converts measured data into images. The electrical imaging logging while drilling technology can intuitively restore the real situation of the stratum, so that the method has corresponding application in the aspects of stratum fracture identification, hole identification, stratum lithology analysis, reservoir analysis and the like.

However, the inventor finds that the following defects exist in the prior art in the implementation process: in the existing electrical imaging logging while drilling technology, after a measurement response value is obtained, only depth normalization or bad data restoration and other preprocessing are performed on the measurement response value, so that the defects of low precision, low resolution, unclear image and the like of a generated image are caused, and subsequent stratum evaluation and data application based on the image are influenced.

Disclosure of Invention

In view of the above, the present invention has been made to provide an image generation method and apparatus based on electrical imaging while drilling that overcome or at least partially solve the above-mentioned problems.

According to one aspect of the invention, an image generation method based on electrical imaging while drilling is provided, which comprises the following steps: calculating eccentric orientations corresponding to different logging depths according to measured response values of the while-drilling electrical imaging measurement; determining eccentricity and formation resistivity corresponding to different logging depths according to the measurement response value and the eccentric azimuths corresponding to the different logging depths; constructing a first equivalent stratum numerical model under the eccentric environment of the borehole by using the eccentric azimuth, the eccentric distance and the stratum resistivity corresponding to the different logging depths; constructing a second equivalent stratum numerical model under the non-borehole eccentric environment corresponding to the first equivalent stratum numerical model; aiming at any one well circumferential direction in any logging depth, taking the ratio of a second simulation response value of the second equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth and a first simulation response value of the first equivalent stratigraphic numerical model as an eccentricity correction coefficient; correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value; and generating an electrical while drilling image based on the eccentricity correction response value.

In an optional embodiment, the determining the eccentricity and the formation resistivity corresponding to the different logging depths according to the measured response value and the eccentricity orientations corresponding to the different logging depths further includes:

an interpretation chart of eccentricity-stratum resistivity-simulation response data is constructed in advance; the interpretation chart comprises simulation response values of corresponding eccentric azimuths under the conditions of a plurality of eccentric distances and a plurality of formation resistivities;

and respectively searching the interpretation chart by utilizing the eccentric azimuth corresponding to each logging depth so as to determine the eccentric distance and the formation resistivity corresponding to each logging depth.

In an alternative embodiment, the pre-constructed interpretation plate of eccentricity-formation resistivity-simulated response data specifically comprises:

constructing a dynamic parameter stratum numerical simulation model;

respectively taking the eccentricity and the formation resistivity as model dynamic parameters, obtaining a model set under various value combinations of the eccentricity and the formation resistivity through the change of the model dynamic parameters, and carrying out numerical simulation on the model set to obtain corresponding simulation response values under the conditions of a plurality of eccentricities and a plurality of formation resistivities;

and drawing an explanation plate of the eccentricity-stratum resistivity-simulation response data according to the corresponding simulation response values under the conditions of the multiple eccentricities and the multiple stratum resistivities.

In an optional embodiment, after the calculating the eccentric locations corresponding to the different logging depths, the method further comprises: and correcting abnormal points of the eccentric azimuths corresponding to the different logging depths.

In an alternative embodiment, after the obtaining the eccentricity correction response value, the method further comprises: carrying out focusing processing on the eccentricity correction response value to obtain a focusing correction response value;

then the generating an electrical while drilling image based on the eccentricity correction response value specifically includes: generating an electrical while drilling image based on the focus correction response value.

In an optional embodiment, the performing the focus processing on the eccentricity correction response value to obtain a focus correction response value further comprises:

constructing a third equivalent stratigraphic numerical model of the stratified stratum and a corresponding fourth equivalent stratigraphic numerical model which is uniform and infinitely thick;

aiming at any one well circumferential direction in any logging depth, taking the ratio of a fourth simulation response value of the fourth equivalent stratum numerical model corresponding to the well circumferential direction in the logging depth and a third simulation response value of the third equivalent stratum numerical model as a focusing correction coefficient;

and carrying out focus correction on the eccentricity correction response value by using the focus correction coefficient to obtain a focus correction response value.

In an optional embodiment, the constructing a third equivalent stratigraphic numerical model of the stratified formation further comprises:

identifying a resistivity layered interface, and determining each layer according to the resistivity layered interface;

and calculating the resistivity and the surrounding rock resistivity of each layer, and constructing a third equivalent stratum numerical model of the stratified stratum according to the resistivity and the surrounding rock resistivity of each layer.

According to another aspect of the present invention, there is provided an image generation apparatus based on electrical imaging while drilling, comprising:

the calculation module is used for calculating the eccentric orientations corresponding to different logging depths according to the measured response values of the electrical imaging while drilling;

the determining module is used for determining the eccentricity and the formation resistivity corresponding to different logging depths according to the measurement response value and the eccentric azimuths corresponding to the different logging depths;

the construction module is used for constructing a first equivalent stratum numerical model under the eccentric environment of the borehole by utilizing the eccentric azimuth, the eccentric distance and the stratum resistivity corresponding to the different logging depths; constructing a second equivalent stratum numerical model under the non-borehole eccentric environment corresponding to the first equivalent stratum numerical model;

the eccentricity correction module is used for aiming at any one circumferential direction in any logging depth, and taking the ratio of a second simulation response value of the second equivalent stratum numerical model corresponding to the circumferential direction in the logging depth and a first simulation response value of the first equivalent stratum numerical model as an eccentricity correction coefficient; and correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value;

and the image generation module is used for generating an electrical imaging while drilling image based on the eccentricity correction response value.

In an optional embodiment, the determining module is further configured to: an interpretation chart of eccentricity-stratum resistivity-simulation response data is constructed in advance; the interpretation chart comprises simulation response values of corresponding eccentric azimuths under the conditions of a plurality of eccentric distances and a plurality of formation resistivities; and respectively searching the interpretation chart by utilizing the eccentric azimuth corresponding to each logging depth so as to determine the eccentric distance and the formation resistivity corresponding to each logging depth.

In an optional embodiment, the determining module is further configured to: constructing a dynamic parameter stratum numerical simulation model;

In an alternative embodiment, the apparatus further comprises: and the abnormal point correction module is used for correcting the abnormal points of the eccentric azimuths corresponding to the different logging depths after calculating the eccentric azimuths corresponding to the different logging depths.

In an alternative embodiment, the apparatus further comprises: a focusing correction module, configured to perform focusing processing on the eccentricity correction response value after the eccentricity correction response value is obtained, so as to obtain a focusing correction response value;

the image generation module is further to: generating an electrical while drilling image based on the focus correction response value.

In an optional embodiment, the focus correction module is further configured to: constructing a third equivalent stratigraphic numerical model of the stratified stratum and a corresponding fourth equivalent stratigraphic numerical model which is uniform and infinitely thick;

In an optional embodiment, the focus correction module is further configured to: identifying a resistivity layered interface, and determining each layer according to the resistivity layered interface;

According to yet another aspect of the present invention, there is provided a computing device comprising: the system comprises a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface complete mutual communication through the communication bus;

the memory is used for storing at least one executable instruction, and the executable instruction enables the processor to execute the operation corresponding to the image generation method based on the electrical imaging while drilling.

According to still another aspect of the present invention, a computer storage medium is provided, wherein at least one executable instruction is stored in the storage medium, and the executable instruction causes a processor to execute operations corresponding to the image generation method based on while-drilling electrical imaging.

The invention discloses an image generation method and device based on while-drilling electrical imaging, which comprises the following steps: calculating eccentric orientations corresponding to different logging depths according to measured response values of the while-drilling electrical imaging measurement; determining eccentricity and formation resistivity corresponding to different logging depths; constructing a first equivalent stratigraphic numerical model under the eccentric environment of the borehole; constructing a second equivalent stratigraphic numerical model under the non-borehole eccentric environment; taking the ratio of a second simulation response value of a second equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth to a first simulation response value of a first equivalent stratigraphic numerical model as an eccentricity correction coefficient; correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value; and generating an electrical imaging while drilling image. According to the scheme, the resolution and the definition of the while-drilling electrical imaging image can be improved, and the stratum analysis and application precision based on the while-drilling electrical imaging image is improved.

The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the embodiments of the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a schematic flow chart illustrating an image generation method based on electrical imaging while drilling according to an embodiment of the present invention;

FIG. 2 is a flow chart illustrating a method for calculating an eccentric orientation according to an embodiment of the present invention;

FIG. 3 is a diagram illustrating a value pair fit curve corresponding to a logging depth according to an embodiment of the present invention;

fig. 4 is a schematic flow chart illustrating an anomaly correction method according to an embodiment of the present invention;

FIG. 5 is a schematic flow chart illustrating a method for determining eccentricity and formation resistivity for different logging depths according to an embodiment of the present invention;

FIG. 6 is a flowchart illustrating a method for generating an interpretive plate according to an embodiment of the present invention;

FIG. 7 is a graph showing simulated response value variation curves for different eccentricities according to an embodiment of the present invention;

FIG. 8 is a diagram illustrating an explanation plate according to an embodiment of the present invention;

FIG. 9 is a schematic diagram illustrating a comparison of an electrical while drilling imaging image provided by an embodiment of the invention;

FIG. 10 is a schematic flow chart illustrating an image generation method based on electrical imaging while drilling according to a second embodiment of the present invention;

fig. 11 is a schematic flow chart illustrating a method for generating a focus correction response value according to a second embodiment of the present invention;

FIG. 12 is a schematic diagram illustrating a comparison of an electrical while drilling imaging image provided by a second embodiment of the invention;

fig. 13 is a schematic structural diagram illustrating an image generating device based on while-drilling electrical imaging according to a third embodiment of the present invention;

fig. 14 shows a schematic structural diagram of a computing device according to a fifth embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Example one

Fig. 1 shows a schematic flowchart of an image generation method based on electrical imaging while drilling according to an embodiment of the present invention.

In the electrical imaging logging while drilling well, the electrical imaging while drilling instrument has wide application. The electric imaging while drilling instrument adopts a rotation measurement mode. I.e., at each logging depth, data for multiple azimuths is measured at a 360 deg. azimuth around the well. However, in logging environments such as highly deviated wells and horizontal wells, the electrical imaging while drilling instrument usually has a certain degree of eccentricity, so that the electrical imaging while drilling instrument is located at the same logging depth, and the gap between the instrument and the well wall is different during measurement around the well, so that the measured data is affected by the gap in different directions and is different in size, thereby the formation state cannot be truly reflected, and the image accuracy and definition are affected.

The image generation method based on while-drilling electrical imaging provided by the embodiment of the invention improves the accuracy and definition of the final image by performing eccentricity correction on the measurement response value obtained by measurement of the while-drilling electrical imaging instrument.

As shown in fig. 1, the method comprises the steps of:

and step S110, calculating the eccentric orientations corresponding to different logging depths according to the measured response values of the electrical imaging while drilling measurement.

The response value of the measurement while drilling electric imaging is data obtained by actual measurement of the while drilling electric imaging instrument, and eccentric directions corresponding to different logging depths can be obtained by analyzing the measurement response value.

In an alternative embodiment, the method shown in fig. 2 may be specifically used to calculate the eccentric orientation for different logging depths. As shown in fig. 2, the method includes the following steps S111 to S114:

and step S111, performing time-depth conversion on the measurement response value according to the measured while-drilling electrical imaging measurement response value.

The data obtained by the initial measurement of the electrical imaging while drilling instrument is time domain data, and in order to facilitate subsequent data processing, time-depth conversion is carried out on the time domain data in the step so as to convert the time domain data into depth domain data. The subsequent processing steps are processed on the basis of the depth domain data after the time-depth conversion.

The depth domain data obtained by time-depth conversion of the measurement response values are in particular the measurement response values of 360 degrees around the well with the logging depth as an index, namely the measurement response values corresponding to all azimuth angles around the well at different logging depths can be obtained through time-depth conversion. In some electrical while drilling instruments, the measured response is specifically a current mode response.

Step S112, aiming at any logging depth, a numerical value pair of an azimuth angle corresponding to the logging depth and a measurement response value is constructed.

Each log depth corresponds to a plurality of azimuth angles, each azimuth angle having a respective measured response value. Each azimuth angle and the corresponding measurement response value form a value pair, and each logging depth can correspond to a plurality of value pairs, and the number of the value pairs is consistent with the number of the divided azimuth angles.

For example, 120 columns of measurement response values are generated after time-depth conversion, the 120 columns of measurement response values are expanded according to the lower edge, the first column of measurement response values corresponds to the periwellic azimuth angle of 0 degrees, the second column of data corresponds to the periwellic azimuth angle of 3 degrees, … … degrees, and the like, the 120 th column of data corresponds to the periwellic azimuth angle of 357 degrees, and the periwellic azimuth angle is taken as an independent variableX：

X=（x₁，x₂，x₃……，x₁₁₉，x₁₂₀) = (0, 3, 6 … …, 354, 357) (equation 1)

Taking the measured response value as a dependent variable Y:

Y=（y₁，y₂，y₃……，y₁₁₉，y₁₂₀) (formula 2)

The value pair is (x)_i，y_i) I =1, 2 … … 120, i.e. each logging depth corresponds to 120 pairs of values.

Step S113, fitting the numerical value pair corresponding to any logging depth to identify the extreme value corresponding to the logging depth.

And fitting the plurality of numerical value pairs corresponding to each logging depth by adopting a corresponding fitting mode, thereby obtaining a numerical value pair fitting curve corresponding to each logging depth, and identifying a maximum value or a minimum value in the curve.

In an alternative implementation, the embodiment of the present invention uses a gaussian fitting algorithm in the non-linear fitting algorithm to perform the fitting. For example, the fitting may be performed using the following equation 3.

(formula 3)

In the formula 3, the first and second groups,μis the average of the pair of values,σis the standard deviation of the value pairs.

Fig. 3 is a schematic diagram illustrating a value pair fitting curve corresponding to a logging depth according to an embodiment of the present invention. Each scatter in fig. 3 corresponds to each value pair, and the abscissa of the scatter is the periazimuth (corresponding to the periazimuth in fig. 3) and the ordinate is the measured response (corresponding to the current mode response in fig. 3). The curve in fig. 3 is a fitted curve for each scatter point. And the extreme value of the fitting curve is the extreme value corresponding to the logging depth.

And S114, determining the eccentric azimuth of the logging depth according to the azimuth angle of the extreme value corresponding to any logging depth.

Specifically, the opposite direction of the azimuth angle of the maximum value corresponding to the logging depth is the eccentric azimuth of the logging depth; or the azimuth angle of the minimum value corresponding to the logging depth is the eccentric azimuth of the logging depth.

Furthermore, in an alternative embodiment, the determined off-center orientation is normalized for subsequent data processing. Specifically, after the eccentric bearing is determined, the bearing number of the eccentric bearing, that is, the eccentric bearing number, is identified. Wherein each off-center azimuth number corresponds to a divided azimuth.

Taking the example that the first column of measurement response values corresponds to the well circumference azimuth angle of 0 °, the second column of data corresponds to the well circumference azimuth angle of 3 °, … …, and so on, and the 120 th column of data corresponds to the well circumference azimuth angle of 357 °, the relation between the eccentric azimuth number and the eccentric azimuth corresponding to each logging depth is as shown in formula 4:

Azi _i =EccN _i *3°，i=1，2，3……M (formula 4)

In the formula 4, the first and second groups of the compound,EccN _idenotes the firstiThe eccentric azimuth number corresponding to each logging depth,Azi _iis shown asiThe eccentric position corresponding to each logging depth,ithe well-logging depth numbers are numbered,Mis the total number of log depths.

As an optional implementation manner of the embodiment of the present invention, after calculating the eccentric orientations corresponding to different logging depths in step S110, in order to improve the processing accuracy of subsequent data, the embodiment of the present invention further includes: and correcting the abnormal point of the eccentric azimuth obtained by calculation. The specific implementation process of correcting the abnormal point may refer to steps S115 to S118 shown in fig. 4:

and step S115, calculating the eccentric azimuth mean value corresponding to each logging depth unit.

To improve data processing efficiency, the embodiment of the present invention divides the whole well depth into a plurality of logging depth units, which may be 1 meter or the like. And then calculating the eccentric azimuth mean value corresponding to each logging depth unit. For example, the eccentric azimuth mean corresponding to each logging depth unit can be obtained by the following formula 5.

(formula 5)

In the formula 5, the first and second groups of the chemical substances,Lrepresenting the number of measurement depths contained within each logging depth unit,Azi _jiis shown asjThe first unit of logging depthiThe eccentric position corresponding to each measured depth,nrepresents the number of units of logging depth,Ф _jis shown asjMean value of the eccentricity azimuth of the individual logging depth units.

And S116, dividing the window length according to the eccentric azimuth mean value corresponding to each logging depth unit.

Specifically, in order to further reduce subsequent data processing capacity, improve execution efficiency of the method and reduce misjudgment rate of abnormal points, after calculating the eccentric azimuth mean value corresponding to each logging depth unit, the logging depth units are aggregated by adopting a corresponding aggregation algorithm based on the eccentric azimuth mean value corresponding to each logging depth unit, and a corresponding window length is generated according to an aggregation result. Wherein each cluster corresponds to a window length, one window length corresponding to one or more logging depth units.

For example, a difference between the mean values of the eccentric orientations of the adjacent logging depth units may be calculated, and if the difference is smaller than a preset angle threshold (e.g., 5 °), the adjacent logging depth units are merged.

And step S117, acquiring a variation curve of the eccentric azimuth corresponding to each window length along with the logging depth, and taking a jumping point in the variation curve as an abnormal point in the window length.

In the case of no outliers, the curve of the eccentricity orientation corresponding to each window length as a function of the logging depth is continuous, and the eccentricity orientation corresponding to each logging depth within each window length should be within a certain range. Based on this, the embodiment of the present invention uses the jumping point in the variation curve as the abnormal point within the window length. For example, for any window length, if the eccentric azimuth of a certain logging depth is greater than twice the mean value of the eccentric azimuths of all logging depths in the window length, or if the eccentric azimuth of a certain logging depth is less than half the mean value of the eccentric azimuths of all logging depths in the window length, the point corresponding to the logging depth is taken as an abnormal point.

In step S118, the abnormal point is corrected.

In an optional correction mode, the abnormal point can be corrected by using the eccentric position corresponding to the normal point adjacent to the abnormal point. For example, the correction of the outlier can be performed using the following equation 6:

(formula 6)

In the formula 6, the first and second groups,MD _cthe logging depth corresponding to the abnormal point C is obtained,MD _A、MD _Brespectively, the logging depths corresponding to the normal point A, B before and after the adjacent outlier C,Azi _A、Azi _Bare respectively provided withIndicating an off-center orientation corresponding to the normal point A, B,Azi _cthe corrected eccentric azimuth of the abnormal point C is shown.

In addition, in order to further simplify subsequent operation, eliminate statistical errors and improve the data processing precision of the method. The embodiment of the invention can also carry out curve filtering on the eccentric azimuth curve of the eccentric azimuth in each window length along with the change of the logging depth. For example, a five-point mean filtering algorithm may be used for the filtering process, and so on. And then subsequently processing data based on the eccentric position after the filtering processing. The five-point mean filtering algorithm can be specifically referred to as formula 7.

(equation 7)

In the formula 7, the first and second groups,Azi _jfor filtering the front window lengthjThe eccentric position corresponding to each logging depth,

for filtering the rear window lengthjAnd (4) eccentric position corresponding to each logging depth.

And S120, determining the eccentricity and the formation resistivity corresponding to different logging depths according to the measurement response value and the eccentric orientations corresponding to different logging depths.

And simulating the mapping relation of the eccentricity, the formation resistivity, the eccentricity azimuth and the response value by adopting a numerical simulation algorithm, and determining the eccentricity and the formation resistivity corresponding to different logging depths based on the mapping relation and the eccentricity azimuth corresponding to different logging depths.

In an alternative embodiment, the method of FIG. 5 may be used to determine the eccentricity and formation resistivity for different logging depths. As shown in fig. 5, the method includes the following steps S121 to S122.

Step S121, constructing an interpretation plate of eccentricity-formation resistivity-simulation response data in advance; the explanation chart contains simulation response values of corresponding eccentric azimuths under the conditions of a plurality of eccentricity and a plurality of formation resistivity.

Specifically, the explanation plate can be obtained by steps S1211 to S1213 shown in fig. 6:

s1211, constructing a dynamic parameter stratum numerical simulation model.

The eccentricity parameter and the formation resistivity parameter in the dynamic parameter formation numerical simulation model can be dynamically changed. The stratum numerical simulation model is a uniform infinite thick stratum model, and the adopted simulation algorithm can be a finite element method and the like. Specifically, according to the structure and the working principle of the while-drilling electrical imaging instrument, a finite element method is adopted to construct the dynamic parameter stratum numerical simulation model.

According to the working principle of the electrical imaging while drilling instrument, a magnetic field wave equation is constructed to obtain the electromagnetic response condition of an excitation source in space, and specifically, a Maxwell equation set is written into a generalized form containing magnetic charge and magnetic current as follows:

(formula 8)

(formula 9)

(formula 10)

(formula 11)

In the equations 8, 9, 10 and 11,▽the rotation operator is represented by a rotation operator,Ewhich represents the strength of the electric field,rwhich is indicative of a variable of the displacement,ta time variable is represented by a time variable,Bwhich represents the intensity of the magnetic induction,Hwhich is indicative of the strength of the magnetic field,Mwhich is indicative of the density of the magnetic flow,ρ _mwhich represents the density of the magnetic charge,Dthe electrical displacement is represented by a displacement of potential,Jit is shown that the current density is,ρrepresents the total charge density.

Then, the symmetry of Maxwell equation system in a generalized form is utilized for replacement, wherein the field quantity is understood as the superposition of fields generated by two types of sources: the electric charge and current are referred to as the electrical source and the magnetic charge and current are referred to as the magnetic source.

The alternative relationship is shown in equation 12:

(formula 12)

Then the above equations 8-11 are converted to complex form to obtain the following equations 13-16:

(formula 13)

(formula 14)

(formula 15)

(formula 16)

In the equations 13, 14, 15 and 16,Hin order to assist the magnetic field,wis the frequency of the electromagnetic wave and is,μin order to have a magnetic permeability,εin order to have a dielectric constant,iin units of imaginary numbers.

In the special case of being passive, the alternative relation, which is usually called duality principle, only needs to conform to equation 17:

(formula 17)

Based on Maxwell's equations, the magnetic field can be obtainedHThe wave equation of (2) is shown in formula 18, and the wave equation of the magnetic field is solved by using a vector edge finite element method to obtainH：

(formula 18)

Solving and obtaining the magnetic field on the edge of each element in the space by a vector edge finite element methodHThe magnitude of the current flowing out of the surface of the measuring electrode can be solved by applying ampere loop lawIThe current ofIInformation on the formation resistivity parameters may be reflected,Iis solved as shown in equation 19 below:

(formula 19)

In the formula 19, the process is described,Hthe magnetic field intensity of the edges of each element in the space,

for the value of the current flowing out of the electrode surface,dlis the magnetic field integral path infinitesimal.

The formation apparent resistivity information is defined by equation 20:

R_a=K/I(formula 20)

In the formula 20, R_aThe apparent resistivity is shown as a function of,Kin order to be a scale factor,Iis the electrode current.

Step S1212, respectively using the eccentricity and the formation resistivity as dynamic parameters of the model, obtaining a model set under a plurality of value combinations of the eccentricity and the formation resistivity through changes of the dynamic parameters of the model, and performing numerical simulation on the model set to obtain corresponding simulation response values under the conditions of a plurality of eccentricities and a plurality of formation resistivities.

To simplify the construction process of the interpretation plate, the well diameter, mud resistivity and instrument radius of the common well log can be obtained in advance. And keeping the well diameter, the mud resistivity and the instrument radius fixed in the subsequent simulation process of the model, so that an interpretation chart of eccentricity-formation resistivity-simulation response data under the specified well diameter and the specified mud resistivity is obtained subsequently. It should be understood herein that one skilled in the art can construct interpretation charts for different specified hole diameters and/or different mud resistivities to suit different logging environment requirements according to actual needs. The maximum eccentricity corresponding to the dynamic parameter formation numerical simulation model can be determined through the following formula 21 according to the determined hole diameter, mud resistivity and instrument radius.

ECCmax = (R-R)/2 (equation 21)

In the formula 21, the first and second groups,ECCmaxthe maximum eccentricity is represented by the maximum eccentricity,Rthe diameter of the well is shown,rrepresenting the instrument radius.

And further setting the value of the eccentricity parameter to be 0-ECCmax, wherein the value range of the formation resistivity is changed from 0.1-100 times of the resistivity measured by the instrument.

As shown in FIG. 7, FIG. 7 shows simulated response values (corresponding to the current mode response of FIG. 7) for the circumferential well locations with eccentricity Ecc of 0in and 0.7in, respectively.

And step S1213, drawing an interpretation chart of the eccentricity-stratum resistivity-simulation response data according to the corresponding simulation response values under the conditions of a plurality of eccentricities and a plurality of stratum resistivities.

The embodiment of the invention does not limit the drawing mode of the specific explanation plate. For example, in order to increase the search rate, the eccentric azimuth can be determined according to different eccentricities and simulated response values corresponding to different formation resistivities, then the simulated response value corresponding to the difference of 180 degrees with the eccentric azimuth is used as an independent variable, the quotient of the simulated response value corresponding to the difference of 180 degrees with the eccentric azimuth and the simulated response value corresponding to the eccentric azimuth is used as a dependent variable, the value of an eccentricity parameter is 0-ECCmax, the formation resistivity value range is changed from the resistivity measured by an instrument by 0.1-100 times, and an interpretation chart of eccentricity-formation resistivity-simulated response data is drawn.

As for the explanation plate shown in fig. 8, the operating frequency 200KHz, the fixed borehole diameter 8.5in, the mud resistivity 0.08 Ω · m, the analog response value corresponding to the difference of 180 ° from the eccentric azimuth (corresponding to the current mode response Max in fig. 8) as an independent variable, the quotient of the analog response value corresponding to the difference of 180 ° from the eccentric azimuth and the analog response value corresponding to the eccentric azimuth (corresponding to the current mode response Max/Min in fig. 8) as a dependent variable, the eccentricity Ecc respectively takes 0in, 0.4in, 0.6in, 0.7in, 0.8in, and the formation resistivity rt respectively takes 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000.

And S122, respectively searching an interpretation plate by using the eccentric azimuth corresponding to each logging depth to determine the eccentricity and the formation resistivity corresponding to each logging depth.

Each logging depth corresponds to an eccentric azimuth, and the eccentricity and the formation resistivity corresponding to each logging depth can be accurately determined by searching the interpretation chart according to the eccentric azimuth and logging response data at the depth.

S130, constructing a first equivalent stratum numerical model in the eccentric environment of the borehole by using the eccentric azimuth, the eccentric distance and the stratum resistivity corresponding to different logging depths; and constructing a second equivalent stratum numerical model in the non-borehole eccentric environment corresponding to the first equivalent stratum numerical model.

The first equivalent formation numerical model is used for simulating the currently measured well section formation under the condition that the well hole eccentricity exists. The model parameters include the eccentric azimuth and logging response data corresponding to the different logging depths obtained in step S110, and the eccentricity and formation resistivity corresponding to the different logging depths obtained in step S120. And also including hole diameter, mud resistivity parameters. The embodiment of the invention is to construct a first equivalent stratum numerical model under the eccentric environment of the borehole by combining the parameters of the borehole diameter and the mud resistivity.

The second equivalent stratigraphic numerical model is used for simulating the currently measured interval stratigraphic under the condition that the borehole eccentricity does not exist. Compared with the first equivalent formation numerical model, the second equivalent formation numerical model does not consider the influences of the borehole diameter, the mud (namely, the mud resistivity is equal to the formation resistivity), the eccentricity (ECC =0 in) and the eccentricity azimuth (Azi = 0) under the condition of the same formation resistivity.

Specifically, the model can be constructed by the parameters and a corresponding model construction method.

Step S140, regarding any one of the circumferential directions in any one of the logging depths, taking a ratio of a second simulation response value of the second equivalent stratigraphic numerical model corresponding to the circumferential direction in the logging depth to a first simulation response value of the first equivalent stratigraphic numerical model as an eccentricity correction coefficient.

And aiming at any well circumferential direction of any logging depth, the first equivalent stratum numerical model outputs a corresponding first simulation response value, the second equivalent stratum numerical model outputs a corresponding second simulation response value, and the ratio of the second simulation response value to the first simulation response value is used as the eccentricity correction coefficient of the well circumferential direction of the logging depth.

Specifically, the eccentricity correction coefficient can be calculated using the following equation 22:

Cor _i =RA _Ci /RA _i(formula 22)

In the formula 22, the first and second groups of the functional groups,Cor _irepresenting well log depthPLower partiThe eccentricity correction coefficient of the well circumferential direction,RA _Cirepresenting well log depthPLower partiA second simulated response value for the well circumferential location,RA _irepresenting well log depthPLower partiA first simulated response value for the well circumferential orientation.

And S150, correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value.

Specifically, for each circumferential position at each logging depth, the measurement response value of the circumferential position at the logging depth is corrected according to the eccentricity correction coefficient of the circumferential position at the logging depth, for example, the product of the eccentricity correction coefficient and the measurement response value may be used as the eccentricity correction response value of the circumferential position at the logging depth.

Specifically, fixing the logging depth, reading the measurement response value of each well circumferential direction under the logging depth, and correcting the measurement response value under the logging depth to obtain an eccentric correction response value under the logging depth; and then correcting the corresponding measurement values of all the well circumferential directions of the next logging depth by adopting a corresponding method until all the measurement response values are corrected.

And step S160, generating an electrical imaging while drilling image based on the eccentricity correction response value.

As shown in fig. 9, image a is a still image obtained by using the prior art, image B is a moving image obtained by using the prior art, image C is a still image obtained by using the method according to the embodiment of the present invention under the same conditions as image a, and image D is a moving image obtained by using the method according to the embodiment of the present invention under the same conditions as image B. As can be seen from the figure, image C has a higher sharpness than image a, and image D has a higher sharpness than image B.

Therefore, the borehole eccentricity correction is further performed after the measurement response value is obtained, and the while-drilling electrical imaging image is generated based on the corrected data, so that the resolution and the definition of the while-drilling electrical imaging image are improved, and the stratum analysis and application accuracy based on the while-drilling electrical imaging image are improved; in addition, a first equivalent stratigraphic numerical model and a second equivalent stratigraphic numerical model under the eccentric environment of the borehole are constructed in the embodiment of the invention; and taking the ratio of the second simulation response value of the second equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth to the first simulation response value of the first equivalent stratigraphic numerical model as an eccentricity correction coefficient, thereby improving the eccentricity correction precision.

Example two

Fig. 10 is a flowchart illustrating an image generation method based on electrical imaging while drilling according to a second embodiment of the present invention. As shown in fig. 10, the method includes the steps of:

in step S1010, the decentering correction response value is subjected to focusing processing to obtain a focusing correction response value.

After the eccentricity correction response value is obtained, in order to further eliminate the influence of the surrounding rock, the embodiment of the invention further performs focusing processing on the obtained eccentricity correction response value, so as to obtain a focusing correction response value.

In an alternative embodiment, the focus correction response value may be obtained using the focus processing method shown in fig. 11. As shown in fig. 11, the focus processing method includes steps S1011 to S1014:

step S1011, a third equivalent stratigraphic numerical model of the stratified stratigraphic is constructed.

Specifically, a resistivity layered interface is identified, and each layer is determined according to the resistivity layered interface. And acquiring the formation resistivity corresponding to the different logging depths obtained in the first embodiment, and identifying the resistivity layered interface by adopting a squaring difference algorithm.

And acquiring the formation resistivity corresponding to the different logging depths obtained in the first embodiment, and performing squaring treatment by adopting a threshold segmentation method. The squaring processing formula may be the following formula 23:

(formula 23)

In the formula 23, the first and second groups,numthe number of the logging depths is the number,mthe window length is controlled for the purpose of squaring,Rt _jis as followsjThe resistivity value corresponding to each logging depth,A ₀in order to be a segmentation threshold value, the segmentation threshold value,Pthe calculated segment reference line.

As can be seen from equation 23, when P: (Rt _j) Value greater thanA ₀And is window longmAnd when the inner extreme value is the boundary position of the squaring treatment.

After the squared boundary locations are obtained, two adjacent boundary locations form a log segment. And regarding the logging section generated after any square waveform processing, taking the average value of the measurement values of the central length of the logging section as the measurement value of the logging section. And determining a resistivity layering interface according to the boundary of the square wave curve, and then determining each layer.

And further calculating the resistivity of each layer and the resistivity of the surrounding rock, and constructing a third equivalent stratum numerical model of the stratified stratum according to the resistivity of each layer and the resistivity of the surrounding rock. Specifically, setting fixed wellbore size, offset0in heart distance, 0 off-center azimuth, and resistivity of each layerRTiAnd resistivity of surrounding rockRSiAnd constructing a third equivalent stratigraphic numerical model of the stratified stratum.

Step S1012, a fourth equivalent stratigraphic numerical model with uniform infinite thickness corresponding to the third equivalent stratigraphic numerical model is constructed.

Setting the fixed borehole size (consistent with the third equivalent formation numerical model), the eccentricity of 0in, the eccentricity azimuth of 0 DEG, and the resistivity equal to the resistivity in the square-wave back layerRT=RTiResistivity of surrounding rockRS= RSiAnd establishing a uniform infinite thickness model.

Step S1013, regarding any one well circumferential direction in any logging depth, taking a ratio of a fourth simulation response value of a fourth equivalent formation numerical model corresponding to the well circumferential direction in the logging depth and a third simulation response value of a third equivalent formation numerical model as a focusing correction coefficient.

Specifically, for a measurement point in any one well circumferential direction in any logging depth, the position relationship between the measurement point and the resistivity layered interface is determined, and a response value of the measurement point is simulated by using a third equivalent stratigraphic numerical model, where the response value is a third simulated response value RA of the third equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth_Bi(Azi)。

Correspondingly, a fourth simulation response value RA of a fourth equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth is obtained_0i。

The focus correction factor for any well circumferential location in any log depth is then obtained by equation 24 as follows:

Cor_Bi(Azi)=RA_0i/RA_Bi(Azi) (equation 24)

In formula 24, RA_0iA fourth simulated response value, RA, of a fourth equivalent stratigraphic numerical model representing any peri-well orientation at any log depth_Bi(Azi) is a third simulated response, Cor, of a third equivalent stratigraphic numerical model of the well circumferential orientation in the logging depth_Bi(Azi) is the convergence of the peri-well location in the logging depthThe coke correction factor, Azi, represents the well circumferential orientation, which is greater than or equal to 0 ° and less than or equal to 360 °.

In step S1014, focus correction is performed on the decentering correction response value using the focus correction coefficient to obtain a focus correction response value.

And if any one of the well circumference directions in any logging depth has a corresponding focusing correction coefficient, taking the product of the focusing coefficient corresponding to the well circumference direction in the logging depth and the correction response value of the well circumference direction in the logging depth as the focusing correction response value of the well circumference direction in the logging depth. Specifically, the focus correction response value can be obtained by the following equation 25:

(equation 25)

In the formula 25, the process is described,

representing an eccentricity correction response value, Cor_BiWhich represents the focus correction factor, is,

indicating the focus correction response value.

In addition, in order to further improve the correction effect, the embodiment of the invention further uses the corresponding truncation condition as a constraint. Specifically, the focus correction response value is compared with a value with the minimum influence of the interface on the two sides of the interface to be used as a truncation condition for constraint, and the constrained data is used as the constrained focus correction response value. Wherein, the constraint formula is shown in formula 26:

(formula 26)

In the formula 26, the process is as follows,RA _Rt (Azi)representing the squared value of the layer in which the measurement point is located,RA _Rs (Azi)representing squared values of the surrounding rock

Indicating the focus correction response value after the constraint.

In step S1020, an while-drilling electrical imaging image is generated based on the focus correction response value.

If the step S1010 is subjected to the constraint processing, an electrical imaging while drilling image is further generated according to the constrained focus correction response value.

As shown in fig. 12, an image a is a still image obtained by using the prior art, an image B is a moving image obtained by using the prior art, an image C is a still image obtained by using the method according to the first embodiment of the present invention under the same conditions as the image a, an image D is a moving image obtained by using the method according to the first embodiment of the present invention under the same conditions as the image B, an image E is a still image obtained by using the method according to the second embodiment of the present invention under the same conditions as the image a, and an image F is a moving image obtained by using the method according to the second embodiment of the present invention under the same conditions as the image B. As can be seen, image E has a higher image sharpness than images a and C, and image F has a higher image sharpness than images B and D.

Therefore, the embodiment of the invention further performs focusing processing on the eccentricity correction response value on the basis of eccentricity correction, thereby eliminating the influence of surrounding rocks, further realizing image enhancement processing on the while-drilling electrical imaging image, and improving the definition and resolution of the while-drilling electrical imaging image.

EXAMPLE III

Fig. 13 shows a schematic structural diagram of an image generation apparatus based on electrical imaging while drilling according to a third embodiment of the present invention.

As shown in FIG. 13, the apparatus 1300 includes a calculation module 1310, a determination module 1320, a construction module 1330, an eccentricity correction module 1340, and an image generation module 1350.

The calculation module 1310 is used for calculating eccentric orientations corresponding to different logging depths according to measured while-drilling electrical imaging measurement response values;

a determining module 1320, configured to determine eccentricity and formation resistivity corresponding to different logging depths according to the measurement response value and the eccentric orientations corresponding to the different logging depths;

a constructing module 1330, configured to construct a first equivalent formation numerical model in the borehole eccentric environment by using the eccentric azimuth, the eccentric distance, and the formation resistivity corresponding to the different logging depths; constructing a second equivalent stratum numerical model under the borehole-free eccentric environment corresponding to the first equivalent stratum numerical model;

the eccentricity correction module 1340 is configured to, for any one circumferential direction in any logging depth, use a ratio of a second simulation response value of the second equivalent formation numerical model corresponding to the circumferential direction in the logging depth to a first simulation response value of the first equivalent formation numerical model as an eccentricity correction coefficient; and correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value;

an image generation module 1350 configured to generate an electrical while drilling image based on the eccentricity correction response value.

In an alternative embodiment, the determining module 1320 is further configured to:

In an alternative embodiment, the determining module 1320 is further configured to: constructing a dynamic parameter stratum numerical simulation model;

In an alternative embodiment, the apparatus 1300 further comprises: and an abnormal point correction module (not shown in the figure) for performing abnormal point correction on the eccentric orientations corresponding to the different logging depths after calculating the eccentric orientations corresponding to the different logging depths.

In an alternative embodiment, the apparatus 1300 further comprises: a focus correction module (not shown in the figure) for performing a focus process on the eccentricity correction response value after the eccentricity correction response value is obtained to obtain a focus correction response value;

the image generation module 1350 is further configured to: generating an electrical while drilling image based on the focus correction response value.

and calculating the resistivity and the surrounding rock resistivity of each layer, and constructing the third equivalent stratum numerical model according to the resistivity and the surrounding rock resistivity of each layer.

Therefore, the device can improve the resolution and definition of the while-drilling electrical imaging image and improve the stratum analysis and application precision based on the while-drilling electrical imaging image.

Example four

The fourth embodiment of the present invention provides a non-volatile computer storage medium, where the computer storage medium stores at least one executable instruction, and the computer executable instruction may execute the image generation method based on while-drilling electrical imaging in any of the above method embodiments.

EXAMPLE five

Fig. 14 shows a schematic structural diagram of a computing device according to a fifth embodiment of the present invention. The specific embodiments of the present invention are not intended to limit the specific implementations of computing devices.

As shown in fig. 14, the computing device may include: a processor (processor)1402, a Communications Interface 1404, a memory 1406, and a communication bus 1408.

Wherein: the processor 1402, communication interface 1404, and memory 1406 communicate with each other via a communication bus 1408. A communication interface 1404 for communicating with network elements of other devices, such as clients or other servers. The processor 1402, configured to execute the procedure 1410, may specifically perform relevant steps in the above-described embodiments of the method for generating an image based on while drilling electrical imaging.

In particular, program 1410 may include program code that includes computer operating instructions.

Processor 1402 may be a central processing unit CPU, or an Application Specific Integrated Circuit (ASIC), or one or more Integrated circuits configured to implement an embodiment of the present invention. The computing device includes one or more processors, which may be the same type of processor, such as one or more CPUs; or may be different types of processors such as one or more CPUs and one or more ASICs.

Memory 1406 is used to store programs 1410. Memory 1406 may comprise high-speed RAM memory and may also include non-volatile memory (non-volatile memory), such as at least one disk memory. Program 1410 may be specifically configured to cause processor 1402 to perform operations in any of the method embodiments described above.

The algorithms or displays presented herein are not inherently related to any particular computer, virtual system, or other apparatus. Various general purpose systems may also be used with the teachings herein. The required structure for constructing such a system will be apparent from the description above. In addition, embodiments of the present invention are not directed to any particular programming language. It is appreciated that a variety of programming languages may be used to implement the teachings of the present invention as described herein, and any descriptions of specific languages are provided above to disclose the best mode of the invention.

In the description provided herein, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, various features of the embodiments of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the invention and aiding in the understanding of one or more of the various inventive aspects. However, the disclosed method should not be interpreted as reflecting an intention that: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Those skilled in the art will appreciate that the modules in the device in an embodiment may be adaptively changed and disposed in one or more devices different from the embodiment. The modules or units or components of the embodiments may be combined into one module or unit or component, and furthermore they may be divided into a plurality of sub-modules or sub-units or sub-components. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where at least some of such features and/or processes or elements are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Moreover, those of skill in the art will appreciate that while some embodiments herein include some features included in other embodiments, not others, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments may be used in any combination.

The various component embodiments of the invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that a microprocessor or Digital Signal Processor (DSP) may be used in practice to implement some or all of the functionality of some or all of the components according to embodiments of the present invention. The present invention may also be embodied as apparatus or device programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such programs implementing the present invention may be stored on computer-readable media or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names. The steps in the above embodiments should not be construed as limiting the order of execution unless specified otherwise.

Claims

1. An image generation method based on while-drilling electrical imaging is characterized by comprising the following steps:

calculating eccentric orientations corresponding to different logging depths according to measured response values of the while-drilling electrical imaging measurement;

determining eccentricity and formation resistivity corresponding to different logging depths according to the measurement response value and the eccentric azimuths corresponding to the different logging depths;

constructing a first equivalent stratum numerical model under the eccentric environment of the borehole by using the eccentric azimuth, the eccentric distance and the stratum resistivity corresponding to the different logging depths; constructing a second equivalent stratum numerical model under the non-borehole eccentric environment corresponding to the first equivalent stratum numerical model;

aiming at any one well circumferential direction in any logging depth, taking the ratio of a second simulation response value of the second equivalent stratigraphic numerical model corresponding to the well circumferential direction in the logging depth and a first simulation response value of the first equivalent stratigraphic numerical model as an eccentricity correction coefficient;

correcting the measured response value by using the eccentricity correction coefficient to obtain an eccentricity correction response value;

and generating an electrical while drilling image based on the eccentricity correction response value.

2. The method of claim 1, wherein determining the eccentricity and formation resistivity for different logging depths from the measured response values and the eccentricity orientations for different logging depths further comprises:

3. The method of claim 2, wherein the pre-constructing an interpretation template of eccentricity-formation resistivity-simulated response data specifically comprises:

constructing a dynamic parameter stratum numerical simulation model;

4. The method of claim 1, wherein after the calculating the eccentric orientations corresponding to the different logging depths, the method further comprises:

and correcting abnormal points of the eccentric azimuths corresponding to the different logging depths.

5. The method according to any one of claims 1-4, wherein after said obtaining an eccentricity correction response value, the method further comprises: carrying out focusing processing on the eccentricity correction response value to obtain a focusing correction response value;

6. The method of claim 5, wherein the focus processing the eccentricity correction response value to obtain a focus correction response value further comprises:

7. The method of claim 6, wherein constructing a third equivalent stratigraphic numerical model of a stratified formation further comprises:

8. An image generation device based on while-drilling electrical imaging, characterized by comprising:

9. A computing device, comprising: the system comprises a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface complete mutual communication through the communication bus;

the memory is used for storing at least one executable instruction, and the executable instruction causes the processor to execute the operation corresponding to the image generation method based on the electrical imaging while drilling as described in any one of claims 1-7.

10. A computer storage medium having at least one executable instruction stored therein, the executable instruction causing a processor to perform operations corresponding to the method for generating an image based on while-drilling electrical imaging as recited in any one of claims 1-7.