While-drilling azimuth density clearance correction method and device, equipment and storage medium

Abstract

The invention discloses a while-drilling azimuth density clearance correction method and device, equipment and a storage medium, and relates to the field of petroleum and natural gas development. Comprising the following steps: inputting detector density energy window counting data corresponding to a target depth point in a target drilling well into a density calculation formula used for representing the generation of a while-drilling azimuth density instrument at the scales of standard scale wells with different densities, and outputting first density values of different detectors; a corresponding target radial density sensitivity function is determined from a density sensitivity function database based on the first density value, and a second density value, actually measured by the detector, of the target drilling well is obtained; and inputting the first density value and the second density value into a cost function model, correcting a real stratum density value and a gap in a target density response calculation formula containing a target radial density sensitivity function, and outputting a corrected target gap and a corrected target density value, so as to obtain an accurate gap value and a real stratum density value.

Description

Technical Field

[0001] The invention relates to the field of oil and gas development, and in particular to a method, device, equipment and storage medium for azimuth density gap correction while drilling. Background Art

[0002] Formation density is one of the important parameters for reservoir evaluation and is often used for formation lithology division, porosity calculation and mud content determination. In addition to the functions of conventional gamma-gamma density logging, azimuthal density logging can achieve 360-degree density scanning imaging of the wellbore through the rotation of the drill collar, thereby achieving formation interface determination and formation dip calculation. In the actual process, factors such as the irregular shape of the drilling wellbore and the vibration of the while-drilling instrument during measurement will cause a gap between the azimuthal density logging instrument and the wellbore wall, and the size of the gap changes irregularly and randomly. The detection depth of azimuthal density logging while drilling is shallow and it is very sensitive to changes in the wellbore environment. A tiny gap will lead to distortion of the formation density parameter measurement and low-resolution density imaging results, which is extremely unfavorable for reservoir evaluation and determination of formation structure parameters.

[0003] The exploration and development of tight unconventional oil and gas such as shale oil and shale gas has put forward higher requirements on the measurement accuracy of azimuthal density while drilling. At the same time, the increasingly complex actual drilling environment has brought new challenges to the measurement of azimuthal density while drilling. The traditional gap correction method using ridge rib diagrams and plates is no longer suitable for the gap correction of azimuthal density while drilling instruments.

[0004] In summary, how to correct the density measurement difference caused by the difference between interstitial fluid and formation medium, eliminate the influence of interstitial fluid on density measurement, and realize accurate calculation of formation density are technical problems to be solved in this field. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a method, device, equipment and storage medium for azimuthal density gap correction while drilling, which can correct the density measurement difference caused by the difference between gap fluid and formation medium, eliminate the influence of gap fluid on density measurement, and realize accurate calculation of formation density. The specific scheme is as follows:

[0006] In a first aspect, the present application discloses a method for azimuth density gap correction while drilling, comprising:

[0007] Inputting the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the density while drilling instrument at the standard scale well scale of different densities, so as to output the first density values ​​of different detectors;

[0008] Determine a corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, and obtain a second density value of the target well actually measured by the detector;

[0009] The first density value and the second density value are input into the cost function model so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula including the target radial density sensitivity function, and outputs the corrected target gap and target density value.

[0010] Optionally, before inputting the detector density energy window count data corresponding to the target depth point in the target well into the density calculation formula used to characterize the density while drilling instrument at the standard scale well scale of different densities, the method further includes:

[0011] The azimuth density while drilling instrument is used to perform calibration in standard wells with different densities, and a density calculation formula for the first density value measured by the detector is constructed.

[0012] Optionally, before determining the corresponding target radial density sensitivity function from a density sensitivity function database based on the density value, the method further includes:

[0013] The radial density sensitivity function is added to the density response calculation formula to construct a target density response calculation formula including a reference formation density value, a mud density value, a true formation density value and the radial density sensitivity function.

[0014] Optionally, before adding the radial density sensitivity function to the density response calculation formula, the method further includes:

[0015] A radial density sensitivity function is constructed based on the gap value between the azimuth density while drilling instrument and the wellbore wall of the target well, the gamma ray flux corresponding to the gap value, the detector density energy window count data corresponding to the reference formation density value, and the importance function.

[0016] Optionally, before determining the corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, the method further includes:

[0017] A sensitivity function simulation model is constructed according to the structural parameters of the while drilling azimuth density instrument, so as to use the sensitivity function simulation model to simulate the radial density sensitivity function and instrument response characteristics under different reference formation density conditions, so as to construct a density sensitivity function database.

[0018] Optionally, inputting the first density value and the second density value into a cost function model so that the cost function model corrects the true density value and the gap of the formation in a target density response calculation formula including a target radial density sensitivity function includes:

[0019] Inputting the first density value and the second density value into the cost function model, determining the iteration step length using the LM method to determine the minimum value of the absolute value of the cost function, and judging the relationship between the minimum value and the target threshold;

[0020] If the minimum value is less than the target threshold, the true density value and the gap value of the formation are output;

[0021] If the minimum value is greater than and / or equal to the target threshold, the true formation density value and the gap value are corrected until the minimum value is less than the target threshold.

[0022] Optionally, before inputting the first density value and the second density value into the cost function model, the method further includes:

[0023] A cost function model is constructed using target weights, an L2 norm of a difference between the first density value and the second density value, a regularization parameter, a true formation density value, a gap, and a borehole fluid density.

[0024] In a second aspect, the present application discloses a while-drilling azimuth density gap correction device, comprising:

[0025] A first density determination module is used to input the detector density energy window count data corresponding to the target depth point in the target wellbore into a density calculation formula used to characterize the density while drilling instrument at standard scale wells of different densities, so as to output first density values ​​of different detectors;

[0026] A second density determination module, configured to determine a corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, and obtain a second density value of the target well actually measured by the detector;

[0027] The density gap determination module is used to input the first density value and the second density value into the cost function model so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value.

[0028] In a third aspect, the present application discloses an electronic device, comprising:

[0029] Memory, used to store computer programs;

[0030] A processor is used to execute the computer program to implement the steps of the aforementioned while-drilling azimuth density gap correction method disclosed above.

[0031] In a fourth aspect, the present application discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, the steps of the aforementioned while-drilling azimuth density gap correction method are implemented.

[0032] It can be seen that the present application discloses a method for correcting azimuthal density gap while drilling, comprising: inputting the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the density calculation formula generated by the standard scale well scale of the azimuthal density instrument while drilling at different densities, so as to output the first density value of different detectors; based on the first density value, determining the corresponding target radial density sensitivity function from the density sensitivity function database, and obtaining the second density value of the target wellbore actually measured by the detector; inputting the first density value and the second density value into the cost function model, so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value. It can be seen that the first density value of the detector is determined by inputting the density energy window count data of the target depth point of the target well detected by the detector into the standard density calculation formula, and the corresponding target radial density sensitivity function is determined from the function database based on the correspondence between the first density value and the function, and then the actual density value of the target well measured by the detector is obtained, that is, the second density value, and the first density value and the second density value are input into the cost function model. The target density value and the target gap are inverted and solved through the cost function model, and corrected to obtain accurate gap values ​​and true formation density values, with fast calculation speed and high accuracy, and little influence by wellbore gap and wellbore fluid density. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0034] Figure 1 A flow chart of a method for azimuth density gap correction while drilling disclosed in the present application;

[0035] Figure 2 A flow chart of iterative inversion of azimuth density gap while drilling disclosed in the present application;

[0036] Figure 3A flow chart of a specific while-drilling azimuth density gap correction method disclosed in the present application;

[0037] Figure 4 It is an XZ view of a numerical calculation model of a remote detector of a while drilling azimuth density instrument disclosed in the present application;

[0038] Figure 5 It is an XY view of a numerical calculation model of a remote detector of a while drilling azimuth density instrument disclosed in the present application;

[0039] Figure 6 A near-detector radial density sensitivity function disclosed in this application;

[0040] Figure 7 A radial density sensitivity function of a remote detector disclosed in this application;

[0041] Figure 8 This is a comparison result diagram before and after the gap correction disclosed in the present application;

[0042] Fig. 9 This is a structural schematic diagram of a while-drilling azimuth density gap correction device disclosed in the present application;

[0043] Fig.10 This is a structural diagram of an electronic device disclosed in this application. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0045] Formation density is one of the important parameters for reservoir evaluation and is often used for formation lithology division, porosity calculation and mud content determination. In addition to the functions of conventional gamma-gamma density logging, azimuthal density logging can achieve 360-degree density scanning imaging of the wellbore through the rotation of the drill collar, thereby achieving formation interface determination and formation dip calculation. In the actual process, factors such as the irregular shape of the drilling wellbore and the vibration of the while-drilling instrument during measurement will cause a gap between the azimuthal density logging instrument and the wellbore wall, and the size of the gap changes irregularly and randomly. The detection depth of azimuthal density logging while drilling is shallow and it is very sensitive to changes in the wellbore environment. A tiny gap will lead to distortion of the formation density parameter measurement and low-resolution density imaging results, which is extremely unfavorable for reservoir evaluation and determination of formation structure parameters.

[0046] The exploration and development of tight unconventional oil and gas such as shale oil and shale gas has put forward higher requirements on the measurement accuracy of azimuthal density while drilling. At the same time, the increasingly complex actual drilling environment has brought new challenges to the measurement of azimuthal density while drilling. The traditional gap correction method using ridge rib diagrams and plates is no longer suitable for the gap correction of azimuthal density while drilling instruments.

[0047] To this end, the present application provides a while-drilling azimuthal density gap correction scheme, which can correct the density measurement difference caused by the difference between the gap fluid and the formation medium, eliminate the influence of the gap fluid on the density measurement, and realize the accurate calculation of the formation density.

[0048] Reference Figure 1 As shown, an embodiment of the present invention discloses a method for correcting azimuth density gap while drilling, comprising:

[0049] Step S11: input the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the density while drilling instrument at standard well scales of different densities, so as to output the first density values ​​of different detectors.

[0050] In this embodiment, density gap correction is achieved through a gamma source, an ultrasonic wellbore detector and at least two gamma detectors in the axial direction. Specifically, the density energy window count data of the far gamma detector and the near gamma detector are input into the density calculation formula so that the first density values ​​corresponding to the far gamma detector and the near gamma detector are output respectively through the density calculation formula.

[0051] In this embodiment, before the detector density energy window count data corresponding to the target depth point in the target well is input into the density calculation formula used to characterize the calibration of the while drilling azimuth density instrument in standard calibration wells of different densities, it also includes: using the while drilling azimuth density instrument to calibrate in standard calibration wells of different densities, and constructing a density calculation formula for the first density value measured by the detector. It can be understood that the while drilling azimuth density instrument is calibrated in standard calibration wells of different densities to generate corresponding calibration data, and a density calculation formula for calculating the first density value is constructed. The specific formula is as follows:

[0052]

[0053] Among them, N SS Represents the count value within the density energy window of the gamma detector, N L represents the count value within the density energy window of the far gamma detector, a1, b1, a2, b2 represent the related constants of the near gamma detector and the far gamma detector respectively, which can be obtained by fitting the calibration data; ρ SS represents the first density value measured by the near gamma detector, ρ LRepresents the first density value measured by the far gamma detector.

[0054] Step S12: determining a corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, and obtaining a second density value of the target well actually measured by the detector.

[0055] In this embodiment, the corresponding target radial density sensitivity function is determined from the density sensitivity function database according to the first density value. Specifically, the reference formation density value ρ0 and the corresponding target radial density sensitivity function are selected to obtain the second density value of the target well actually measured by the detector, wherein the drilling data specifically includes the mud density value of the target well, the ultrasonic well diameter, the true density value of the formation, etc.

[0056] In this embodiment, before determining the corresponding target radial density sensitivity function from the density sensitivity function database based on the density value, it also includes: adding the radial density sensitivity function to the density response calculation formula to construct a target density response calculation formula including the reference formation density value, the mud density value, the true formation density value and the radial density sensitivity function. It can be understood that the radial density sensitivity function is added to the density response calculation formula, and the density response calculation formula is Taylor expanded to obtain the expression form of the radial density sensitivity function, that is, the density response calculation formula, and the specific formula is expressed as follows:

[0057]

[0058] Where ρ is the first density value measured by the far and / or near gamma detectors, in g / cm 3 ; ρ0 represents the base bottom density value, ρ mud is the mud density, ρ b is the true density of the formation, in g / cm 3 ; r is the gap value between the azimuth density while drilling instrument and the wellbore wall of the target well, in cm; k1 is a constant coefficient, and PSF(r) is the radial density sensitivity function.

[0059] In this embodiment, before adding the radial density sensitivity function to the density response calculation formula, it also includes: constructing the radial density sensitivity function based on the gap value between the azimuth density instrument while drilling and the wellbore of the target well, the gamma-ray flux corresponding to the gap value, the detector density energy window count data corresponding to the reference formation density value, and the importance function. It can be understood that the radial density sensitivity function is constructed based on the gap value between the azimuth density instrument while drilling and the wellbore of the target well, the gamma-ray flux corresponding to the gap value, the detector density energy window count data corresponding to the reference formation density value, and the importance function. It should be noted that the selected azimuth density instrument while drilling includes 1 gamma source and at least 2 axial gamma detectors. This method is applicable to instruments with dual source distances, each of which has multiple gamma detectors distributed. In addition, ultrasonic caliper measurement data, that is, the second density value, is required in the actual calculation process. The calculation formula of the radial density sensitivity function is as follows:

[0060]

[0061] Where N0 represents the count value of the gamma detector when the reference formation density value is ρ0; Φ0(r D ,Ω') represents the gamma ray flux at space r under the condition of the current reference formation density value ρ0; G(r,Ω'→r D ,Ω) is expressed as the importance function; PSF(r) is only related to the radial distance, so in the above cylindrical coordinate system, the axial z and circumferential θ are integrated over all spatial ranges, where the gamma-ray flux and importance function can be obtained by numerical simulation.

[0062] Step S13: Input the first density value and the second density value into the cost function model so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value.

[0063] In this embodiment, the first density value and the second density value are input into the cost function model, and the cost function model is used to invert the formation true density value and the gap value in the target density response calculation formula, and output the corrected formation true density value and gap value. Figure 2As shown, by inputting the count values ​​within the energy window range of the near and far gamma detectors, the corresponding first density value of the gamma detector is calculated, and then the corresponding reference formation density value and the target radial sensitivity function are selected, and the gap value is inverted in combination with drilling data, such as mud density value, ultrasonic wellbore value, and true formation density value. The inversion result is compared with a preset threshold value, and the true formation density value and the gap value are output. Specifically, at a certain depth point, the density window counts N of the near and far detectors are first input. SS and N L , use the density calculation formula to calculate the density value ρ of the near and far detectors SS and ρ L Then choose the density and ρ L The target radial sensitivity functions of the near and far detectors under the benchmark formation conditions with a similar benchmark formation density value of ρ0, and the mud density ρ during drilling is given. mud and ultrasonic wellbore r are used as initial input parameters to calculate the near and far detector apparent densities, and the LM method is used to determine the iteration step size to obtain the minimum absolute value of the function.

[0064] It can be seen that the present application discloses a method for correcting azimuthal density gap while drilling, comprising: inputting the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the density calculation formula generated by the standard scale well scale of the azimuthal density instrument while drilling at different densities, so as to output the first density value of different detectors; based on the first density value, determining the corresponding target radial density sensitivity function from the density sensitivity function database, and obtaining the second density value of the target wellbore actually measured by the detector; inputting the first density value and the second density value into the cost function model, so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value. It can be seen that the first density value of the detector is determined by inputting the density energy window count data of the target depth point of the target well detected by the detector into the standard density calculation formula, and the corresponding target radial density sensitivity function is determined from the function database based on the correspondence between the first density value and the function, and then the actual density value of the target well measured by the detector is obtained, that is, the second density value, and the first density value and the second density value are input into the cost function model. The target density value and the target gap are inverted and solved through the cost function model, and corrected to obtain accurate gap values ​​and true formation density values, with fast calculation speed and high accuracy, and little influence by wellbore gap and wellbore fluid density.

[0065] Reference Figure 3As shown, the embodiment of the present invention discloses a specific method for azimuth density gap correction while drilling. Compared with the previous embodiment, this embodiment further illustrates and optimizes the technical solution. Specifically:

[0066] Step S21: input the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the density while drilling instrument at standard well scales of different densities, so as to output the first density values ​​of different detectors.

[0067] Step S22: construct a sensitivity function simulation model according to the structural parameters of the azimuth density instrument while drilling, so as to use the sensitivity function simulation model to simulate the radial density sensitivity function and instrument response characteristics under different reference formation density conditions, so as to construct a density sensitivity function database.

[0068] In this embodiment, according to the selected structural parameters of the azimuth density instrument while drilling, a Monte Carlo numerical calculation model, that is, a sensitivity function simulation model, is established to simulate the radial density sensitivity function and instrument response characteristics under different reference density formation conditions, and to construct a density sensitivity function database, such as Figure 4 and Figure 5 As shown in the figure, the sensitivity function simulation model includes: gamma source 1, source collimation port 2, tungsten nickel iron shield 3, near detector window 4, far detector window 5, formation 6, borehole 7, far gamma detector 8, near gamma detector 9, mud diversion channel 10 and drill collar 11. In the numerical calculation process, the formation is divided into grid units with a thickness of 0.25 cm in the radial direction to improve the accuracy of the radial density sensitivity function. The simulation results of the radial density sensitivity function of the near and far gamma detectors are shown in Figure 1. Figure 6 and Figure 7 As shown in the figure, with the increase of radial distance, the radial density sensitivity function first increases and then decreases, and there are obvious differences in the radial sensitivity functions corresponding to different reference formation densities. Therefore, in the actual processing process, it is necessary to establish a density range of 1.0 g / cm 3 ~3.2g / cm 3 , density interval is 0.1g / cm 3 The density sensitivity function database of near and far gamma detectors. It should be noted that the density sensitivity function database matches the azimuth density instrument while drilling. If the structure of the azimuth density instrument while drilling changes, the density sensitivity function database needs to be rebuilt. For example: Taking the dual-detector azimuth density instrument while drilling as an example, a Monte Carlo numerical calculation model is established, and the stratum is divided into 0.5 cm thick layered strata along the radial direction to simulate the radial sensitivity function. In addition, the detection depth and vertical resolution of the azimuth density instrument while drilling are simulated by changing the properties of the stratum. The two constitute the effective detection area of ​​the azimuth density instrument while drilling.

[0069] Step S23: determining a corresponding target radial density sensitivity function from the density sensitivity function database based on the first density value, and obtaining a second density value of the target well actually measured by the detector.

[0070] Step S24: input the first density value and the second density value into the cost function model, and use the LM method to determine the iteration step to determine the minimum value of the absolute value of the cost function, and judge the size relationship between the minimum value and the target threshold.

[0071] In this embodiment, the LM optimization method is used to invert and solve the cost function model, and a program is written to obtain accurate formation density values ​​through iterative calculation. Specifically, the minimum absolute value of the cost function in the cost function model is determined by determining the iteration step size, and the minimum value is judged to be in a magnitude relationship with the target threshold.

[0072] In this embodiment, before inputting the first density value and the second density value into the cost function model, it also includes: constructing a cost function model using a target weight, an L2 norm of the difference between the first density value and the second density value, a regularization parameter, a true formation density value, a gap, and a borehole fluid density. It can be understood that the cost function model is established as follows:

[0073]

[0074] Among them, the first calculated while drilling azimuth density response vector S(p) is consistent with the actual while drilling azimuth density instrument measurement result d s The L2 norm of the difference between the two, that is, e(p) = S(p)-d s , p is the parameter vector to be inverted, including formation density, borehole fluid density and clearance. The second term is the regularization term, which mainly prevents overfitting and suppresses the error caused by radioactive statistical fluctuations. p0 is the reference vector of the initial formation core characteristic parameters, λ is the regularization parameter, W A and W B is the weight.

[0075] Taylor expansion is performed on the above cost function model, and the second order is as follows:

[0076]

[0077] Where Δp is a small perturbation near vector p, g is the derivative of the cost function C(p) with respect to vector p, H is the Hessian matrix, (Δp) T is the transpose of the vector Δp. Perform iterative calculations using the LM method to find the optimal solution and obtain the accurate value of the formation density.

[0078] Step S25: If the minimum value is smaller than the target threshold, the true formation density value and the gap value are output.

[0079] In this embodiment, if the minimum value obtained by the inversion through the above point-by-point inversion method is less than the given target threshold ε, the true formation density value ρ is output. b and the gap value r.

[0080] Step S26: If the minimum value is greater than and / or equal to the target threshold, the true formation density value and the gap value are corrected until the minimum value is less than the target threshold.

[0081] In this embodiment, if the minimum value obtained by the inversion through the above point-by-point inversion method is greater than and / or equal to the given target threshold ε, the reference formation density value and the borehole clearance are corrected. Specifically, the execution jumps to the step of selecting the corresponding target radial sensitivity function until the minimum value is less than the target threshold and the result output condition is met. Figure 8 As shown in the figure, the calculation results of this method are given when the borehole fluid is clear water and the gaps are 1 cm and 2 cm respectively. After gap correction, the calculated formation density value is consistent with the true value of the formation density, and the error is basically within ±0.025 g / cm 3 Within.

[0082] It can be seen that the Monte Carlo numerical simulation method is used to simulate the radial density sensitivity function under different reference density formation conditions, and a database of near and far detector sensitivity functions of the while drilling azimuth density instrument is established. The corresponding target radial sensitivity function in the library is used to characterize the density measurement difference caused by the difference between the interstitial fluid and the formation medium. Through the iterative inversion of the cost function model, the influence of the interstitial fluid on the density measurement is eliminated, and the accurate calculation of the formation density is achieved.

[0083] Reference Fig. 9 As shown, the embodiment of the present invention also discloses a while-drilling azimuth density gap correction device, including:

[0084] The first density determination module 11 is used to input the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the standard well scale of the while drilling azimuth density instrument at different densities, so as to output the first density values ​​of different detectors;

[0085] A second density determination module 12 is used to determine a corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, and obtain a second density value of the target well actually measured by the detector;

[0086] The density gap determination module 13 is used to input the first density value and the second density value into the cost function model so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value.

[0087] It can be seen that the present application discloses inputting the detector density energy window count data corresponding to the target depth point in the target well into the density calculation formula used to characterize the standard scale well scale of the while-drilling azimuthal density instrument at different densities, so as to output the first density value of different detectors; based on the first density value, determining the corresponding target radial density sensitivity function from the density sensitivity function database, and obtaining the second density value of the target well actually measured by the detector; inputting the first density value and the second density value into the cost function model, so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value. It can be seen that the first density value of the detector is determined by inputting the density energy window count data of the target depth point of the target well detected by the detector into the standard density calculation formula, and the corresponding target radial density sensitivity function is determined from the function database based on the correspondence between the first density value and the function, and then the actual density value of the target well measured by the detector is obtained, that is, the second density value, and the first density value and the second density value are input into the cost function model. The target density value and the target gap are inverted and solved through the cost function model, and corrected to obtain accurate gap values ​​and true formation density values, with fast calculation speed and high accuracy, and little influence by wellbore gap and wellbore fluid density.

[0088] Furthermore, the present application also discloses an electronic device. Fig.10 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content in the diagram cannot be regarded as any limitation on the scope of use of the present application.

[0089] Fig.10 A schematic diagram of the structure of an electronic device 20 provided in an embodiment of the present application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 is used to store a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the while-drilling azimuth density gap correction method disclosed in any of the aforementioned embodiments. In addition, the electronic device 20 in this embodiment may specifically be an electronic computer.

[0090] In this embodiment, the power supply 23 is used to provide working voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and the external device, and the communication protocol it follows is any communication protocol that can be applied to the technical solution of the present application, and is not specifically limited here; the input and output interface 25 is used to obtain external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs and is not specifically limited here.

[0091] Among them, the processor 21 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 21 can be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 21 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 21 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 21 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0092] In addition, the memory 22, as a carrier for storing resources, can be a read-only memory, a random access memory, a disk or an optical disk, etc. The resources stored thereon can include an operating system 221, a computer program 222, etc., and the storage method can be temporary storage or permanent storage.

[0093] Among them, the operating system 221 is used to manage and control the hardware devices and computer programs 222 on the electronic device 20, so as to realize the operation and processing of the massive data 223 in the memory 22 by the processor 21, which can be Windows Server, Netware, Unix, Linux, etc. In addition to including a computer program that can be used to complete the drilling azimuth density gap correction method performed by the electronic device 20 disclosed in any of the aforementioned embodiments, the computer program 222 can further include a computer program that can be used to complete other specific tasks. In addition to data received by the electronic device and transmitted from an external device, the data 223 can also include data collected by its own input and output interface 25.

[0094] Furthermore, the present application also discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, the aforementioned disclosed method for correcting the azimuth density gap while drilling is implemented. The specific steps of the method can be referred to the corresponding contents disclosed in the aforementioned embodiments, and will not be repeated here.

[0095] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0096] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, computer software or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to the function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application. The steps of the method or algorithm described in conjunction with the embodiments disclosed herein can be directly implemented with a software module executed by a hardware or processor, or a combination of the two. The software module can be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the technical field.

[0097] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0098] The above is a detailed introduction to the method, device, equipment and storage medium for azimuth density gap correction while drilling provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for azimuth density gap correction while drilling, characterized in that: include: Inputting the detector density energy window count data corresponding to the target depth point in the target wellbore into the density calculation formula used to characterize the density while drilling instrument at the standard scale well scale of different densities, so as to output the first density values ​​of different detectors; Determine a corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, and obtain a second density value of the target well actually measured by the detector; The first density value and the second density value are input into the cost function model so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula including the target radial density sensitivity function, and outputs the corrected target gap and target density value.

2. The method for azimuth density gap correction while drilling according to claim 1, characterized in that: Before inputting the detector density energy window count data corresponding to the target depth point in the target well into the density calculation formula used to characterize the standard well scale of the while drilling azimuth density instrument at different densities, the method also includes: The azimuth density while drilling instrument is used to perform calibration in standard wells with different densities, and a density calculation formula for the first density value measured by the detector is constructed.

3. The method for azimuth density gap correction while drilling according to claim 1, characterized in that: Before determining the corresponding target radial density sensitivity function from the density sensitivity function database based on the density value, the method further includes: The radial density sensitivity function is added to the density response calculation formula to construct a target density response calculation formula including a reference formation density value, a mud density value, a true formation density value and the radial density sensitivity function.

4. The method for azimuth density gap correction while drilling according to claim 3, characterized in that: Before adding the radial density sensitivity function to the density response calculation formula, the method further includes: A radial density sensitivity function is constructed based on the gap value between the azimuth density while drilling instrument and the wellbore wall of the target well, the gamma ray flux corresponding to the gap value, the detector density energy window count data corresponding to the reference formation density value, and the importance function.

5. The method for azimuth density gap correction while drilling according to claim 1, characterized in that: Before determining the corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, the method further includes: A sensitivity function simulation model is constructed according to the structural parameters of the while drilling azimuth density instrument, so as to use the sensitivity function simulation model to simulate the radial density sensitivity function and instrument response characteristics under different reference formation density conditions, so as to construct a density sensitivity function database.

6. The method for azimuth density gap correction while drilling according to claim 1, characterized in that: The step of inputting the first density value and the second density value into a cost function model so that the cost function model corrects the true density value and the gap of the formation in a target density response calculation formula including a target radial density sensitivity function comprises: Inputting the first density value and the second density value into the cost function model, determining the iteration step length using the LM method to determine the minimum value of the absolute value of the cost function, and judging the relationship between the minimum value and the target threshold; If the minimum value is less than the target threshold, the true density value and the gap value of the formation are output; If the minimum value is greater than and / or equal to the target threshold, the true formation density value and the gap value are corrected until the minimum value is less than the target threshold.

7. The method for azimuth density gap correction while drilling according to any one of claims 1 to 6, characterized in that: Before inputting the first density value and the second density value into the cost function model, the method further includes: A cost function model is constructed using target weights, an L2 norm of a difference between the first density value and the second density value, a regularization parameter, a true formation density value, a gap, and a borehole fluid density.

8. A while drilling azimuth density gap correction device, characterized in that: include: A first density determination module is used to input the detector density energy window count data corresponding to the target depth point in the target wellbore into a density calculation formula used to characterize the density while drilling instrument at standard scale wells of different densities, so as to output first density values ​​of different detectors; A second density determination module, configured to determine a corresponding target radial density sensitivity function from a density sensitivity function database based on the first density value, and obtain a second density value of the target well actually measured by the detector; The density gap determination module is used to input the first density value and the second density value into the cost function model so that the cost function model corrects the true density value and gap of the formation in the target density response calculation formula containing the target radial density sensitivity function, and outputs the corrected target gap and target density value.

9. An electronic device, characterized in that: include: Memory, used to store computer programs; A processor is used to execute the computer program to implement the steps of the while drilling azimuth density gap correction method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Used to store computer programs; wherein, when the computer program is executed by a processor, the steps of the while-drilling azimuth density gap correction method as described in any one of claims 1 to 7 are implemented.

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