Data acquisition method, system and equipment for anisotropic stratum in inclined shaft and medium

Abstract

The invention discloses a data acquisition method, system, equipment and medium for anisotropic strata in an inclined shaft, and relates to the technical field of logging data processing.The method comprises the steps that a continuous oblique angle of any measuring point in the inclined shaft serves as an estimated value of a borehole inclination angle of the measuring point, and the variation range of the borehole inclination angle of the measuring point is set; based on the estimated value of the borehole dip angle of each measuring point, the borehole dip angle change range and the three-dimensional induction logging data, a logging response component combination curve of each measuring point is constructed; performing skin effect correction on the two curves corresponding to each measurement point; and determining the intersection point in the two-dimensional cross plot of the two corrected curves corresponding to each measuring point as the truth value of the borehole dip angle and the truth value of the horizontal conductivity of the corresponding measuring point, and further calculating to obtain the truth value of the vertical conductivity of each measuring point. According to the invention, the truth value of the horizontal conductivity and the truth value of the vertical conductivity of the stratum can be obtained with high precision.

Description

Technical Field

[0001] This invention relates to the field of well logging data processing technology, and in particular to a method, system, equipment and medium for acquiring data from anisotropic formations in a deviated well. Background Technology

[0002] It is estimated that about 30% of the world's oil and gas reserves are located in thin sandstone-mudstone interbedded layers. These thin interbedded reservoirs can be considered as macroscopic uniaxial anisotropic strata (or, laterally isotropic strata, abbreviated as TI strata). Detection and identification of these strata are of great significance for the development of oil and gas resources.

[0003] For existing axial induction logging instruments, the vertical resolution is not high enough, so thin, interbedded oil reservoirs are often mistaken for high water saturation layers and missed during logging. Three-dimensional induction logging instruments consist of three perpendicular transmitting coils and three parallel receiving coils. They can detect the horizontal and vertical conductivity of the formation, and can identify formation characteristics from a three-dimensional perspective, giving them an inherent advantage in detecting thin and complex reservoirs.

[0004] Generally, the logging response of three-dimensional induction logging instruments in deviated wells is simultaneously related to the formation's horizontal conductivity, vertical conductivity, and wellbore dip angle, and is highly nonlinear. In addition, the influence of adjacent layers on different components of the logging response is different, all of which increase the difficulty of real-time data processing, interpretation, and evaluation.

[0005] Currently, the main method for processing 3D induction logging data is the multi-parameter nonlinear iterative inversion method. While iterative inversion methods can obtain formation parameters close to the true values, they are typically slow, with the majority of computation time spent calculating the Jacobi matrix of the objective function. Furthermore, the inversion of 3D induction logging data is significantly affected by the estimated values ​​of anisotropic formation conductivity parameters and wellbore dip angle. Inappropriate selection of these estimated values ​​can lead to large errors in the formation conductivity and wellbore dip angle results. Moreover, there are currently no mature technologies, either domestically or internationally, for real-time processing of 3D induction logging data to obtain wellbore dip angle and formation conductivity for reference. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the shortcomings of existing technologies. Specifically, it provides a method, system, equipment, and medium for acquiring data from anisotropic formations within deviated wells, as detailed below:

[0007] 1) In a first aspect, the present invention provides a method for acquiring data from anisotropic formations within a deviated well, the specific technical solution of which is as follows:

[0008] The inclination angle of any measurement point in the deviated well is used as the estimated value of the wellbore inclination angle of that measurement point, and the range of variation of the wellbore inclination angle of that measurement point is set. Based on the estimated value of the wellbore inclination angle of that measurement point, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of that measurement point, the logging response component combination curve of that measurement point is constructed until the logging response component combination curve of each measurement point is obtained. The logging response component combination curve includes two curves that are only related to the horizontal conductivity and the wellbore inclination angle.

[0009] Skin effect correction is performed on the two curves corresponding to each measurement point to obtain two corrected curves for each measurement point.

[0010] The intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point is determined as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point.

[0011] The true value of the vertical conductivity at each measurement point is calculated based on the true value of the horizontal conductivity and the true value of the wellbore inclination angle at each measurement point.

[0012] The beneficial effects of the data acquisition method for anisotropic strata in inclined wells provided by this invention are as follows:

[0013] 1) For each measurement point, it can process the three-dimensional induction logging data of anisotropic formations in deviated wells in real time, and quickly obtain the horizontal conductivity, vertical conductivity and wellbore dip parameters of anisotropic (TI) formation deviated wells. This greatly shortens the logging data processing time, improves the working efficiency of logging instruments, and significantly reduces the cost of testing instruments in the well. It enables three-dimensional induction logging data to be better applied to real-time processing and interpretation evaluation in the field, which is of great significance to the widespread application of three-dimensional induction logging instruments in the field.

[0014] 2) The results of this invention can be applied to the determination of anisotropic TI formation conductivity and wellbore dip angle in any deviated well, especially in highly deviated wells, which broadens the application range of three-dimensional induction logging instruments.

[0015] 3) Since the present invention can obtain the true values ​​of the horizontal and vertical electrical conductivity of the formation in anisotropic TI formation deviated wells with high accuracy, this processing method can accurately determine the thin sand-mudstone interbedded layer, avoiding the misidentification of such thin interbedded oil reservoirs as high water saturation layers in well logging and thus missing them, which is of great significance in well logging.

[0016] Based on the above scheme, the data acquisition method for anisotropic formations in inclined wells of the present invention can be further improved as follows.

[0017] Furthermore, the range of wellbore inclination angle is: (α0-Δα1, α0+Δα2), where α0 represents the estimated value of wellbore inclination angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value.

[0018] Furthermore, it also includes: performing logging in the inclined shaft using a three-dimensional induction logging instrument to obtain three-dimensional induction logging data for each measurement point in the inclined shaft, and performing logging in the inclined shaft using a connecting inclination instrument to obtain the connecting inclination angle for each measurement point in the inclined shaft.

[0019] Furthermore, the mathematical expression for one of the curves that is only related to horizontal conductivity and wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

[0020] 2) Secondly, the present invention also provides a data acquisition system for anisotropic formations within a deviated well, the specific technical solution of which is as follows:

[0021] It includes a curve construction module, a curve correction module, a first truth value determination module, and a second truth value determination module;

[0022] The curve construction module is used to: take the inclination angle of any measurement point in the deviated well as the estimated value of the wellbore inclination angle of that measurement point, and set the range of variation of the wellbore inclination angle of that measurement point. Based on the estimated value of the wellbore inclination angle of that measurement point, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of that measurement point, construct the logging response component combination curve of that measurement point, until the logging response component combination curve of each measurement point is obtained. The logging response component combination curve includes: two curves that are only related to the horizontal conductivity and the wellbore inclination angle.

[0023] The curve correction module is used to perform skin effect correction on the two curves corresponding to each measurement point, so as to obtain two corrected curves corresponding to each measurement point.

[0024] The first truth value determination module is used to: determine the intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point.

[0025] The second truth value determination module is used to calculate the true value of the vertical conductivity of each measurement point based on the true value of the horizontal conductivity and the true value of the wellbore inclination angle.

[0026] Based on the above scheme, the data acquisition system for anisotropic formations in inclined wells of the present invention can be further improved as follows.

[0027] Furthermore, the range of wellbore inclination angle is: (α0-Δα1, α0+Δα2), where α0 represents the estimated value of wellbore inclination angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value.

[0028] Furthermore, it also includes a data acquisition module, which is used to: perform logging in the inclined shaft using a three-dimensional induction logging instrument to obtain three-dimensional induction logging data for each measurement point in the inclined shaft, and perform logging in the inclined shaft using a connecting inclination instrument to obtain the connecting inclination angle for each measurement point in the inclined shaft.

[0029] Furthermore, the mathematical expression for one of the curves that is only related to horizontal conductivity and wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

[0030] 3) In a third aspect, the present invention also provides an electronic device, the electronic device including a processor coupled to a memory, the memory storing at least one computer program, the at least one computer program being loaded and executed by the processor, so as to enable the electronic device to implement the above-mentioned method for acquiring data of anisotropic formations in inclined shafts.

[0031] 4) In a fourth aspect, the present invention also provides a computer-readable storage medium storing at least one computer program, which is loaded and executed by a processor to enable a computer to implement the above-described method for acquiring data from anisotropic formations within a deviated well.

[0032] It should be noted that the beneficial effects of the technical solutions of the second to fourth aspects of the present invention and their corresponding possible implementations can be found in the above description of the technical effects of the first aspect and its corresponding possible implementations, and will not be repeated here. Attached Figure Description

[0033] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0034] Figure 1 Here is a flowchart illustrating a method for acquiring data from anisotropic formations within an inclined shaft, according to an embodiment of the present invention.

[0035] Figure 2 Here is a schematic diagram of the coil system of a three-dimensional induction logging instrument.

[0036] Figure 3 For: A schematic diagram used to illustrate the relationship between the formation coordinate system, the wellbore coordinate system, and the instrument coordinate system;

[0037] Figure 4 Table of 18 TI anisotropic strata parameters;

[0038] Figure 5 For example: the simulated curves of the principal components (XX / YY / ZZ) of the well logging response;

[0039] Figure 6 For: the simulated curves of the well logging response cross components (XZ / ZX) and their responses;

[0040] Figure 7 SECσ is the combined quantity after skin effect correction. HA and SECσ HC The response simulation curve;

[0041] Figure 8 For: SECσ HA and SECσ HC α~σ h Two-dimensional intersection diagram;

[0042] Figure 9 For example: when the estimated wellbore inclination angle is 60°, the range of wellbore inclination angle variation α∈(50°~70°) and α∈(40°~80°) is set, and the real-time processing results of wellbore inclination angle under different angle scanning ranges are obtained.

[0043] Figure 10 The following is a list of formation horizontal and vertical conductivity curves obtained with and without noise, when the estimated wellbore dip angle is 60° and the search range is (40°~80°).

[0044] Figure 11 The following is a list of formation horizontal and vertical conductivity curves obtained with and without noise, when the estimated wellbore dip angle is 60° and the search range is (50°~70°).

[0045] Figure 12 The results are: wellbore inclination angles with and without noise, when the estimated wellbore inclination angle is 30° and the angle scanning range is (10°~50°);

[0046] Figure 13 The search range for the wellbore inclination angle is (10°~50°) when the estimated value of the wellbore inclination angle is 30°, and the formation horizontal and vertical conductivity curves are obtained under noise conditions when the true value of the wellbore inclination angle is 30°.

[0047] Figure 14 The results are: when the estimated wellbore inclination angle is 80°, the wellbore inclination angle results are compared with and without noise within the angle scanning range (60°~88°);

[0048] Figure 15 The search range for the wellbore inclination angle is (60°~88°) when the estimated value of the wellbore inclination angle is 80°, and the formation horizontal and vertical conductivity curves obtained under noise conditions when the true value of the wellbore inclination angle is 80°.

[0049] Figure 16 Here is a schematic diagram of the structure of a data acquisition system for anisotropic formations within an inclined shaft, according to an embodiment of the present invention.

[0050] Figure 17 See: A schematic diagram of the structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0052] like Figure 1 As shown in the figure, a data acquisition method for anisotropic formations in a deviated well according to an embodiment of the present invention includes the following steps:

[0053] S1. Take the inclination angle of any measurement point in the deviated well as the estimated value of the wellbore inclination angle of that measurement point, and set the range of variation of the wellbore inclination angle of that measurement point. Based on the estimated value of the wellbore inclination angle of that measurement point, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of that measurement point, construct the logging response component combination curve of that measurement point until the logging response component combination curve of each measurement point is obtained. The logging response component combination curve includes two curves that are only related to the horizontal conductivity and the wellbore inclination angle.

[0054] S2. Perform skin effect correction on the two curves corresponding to each measurement point to obtain two corrected curves for each measurement point;

[0055] S3. The intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point is determined as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point.

[0056] S4. Calculate the true value of the vertical conductivity at each measurement point based on the true value of the horizontal conductivity and the true value of the wellbore inclination angle.

[0057] Optionally, in the above technical solution, the range of wellbore inclination angle is: (α0-Δα1, α0+Δα2), where α0 represents the estimated value of wellbore inclination angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value.

[0058] Optionally, the above technical solution also includes: performing logging in the inclined well using a three-dimensional induction logging instrument to obtain three-dimensional induction logging data for each measurement point in the inclined well, and performing logging in the inclined well using a connecting inclination instrument to obtain the connecting inclination angle for each measurement point in the inclined well.

[0059] Optionally, in the above technical solution, the mathematical expression for one of the curves that is only related to horizontal conductivity and wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

[0060] The data acquisition method for anisotropic formations in inclined wells according to the present invention is described in the following embodiments, including:

[0061] S101. Logging is performed in the inclined shaft using a three-dimensional induction logging instrument to obtain three-dimensional induction logging data for each measurement point in the inclined shaft. Logging is also performed in the inclined shaft using a connecting inclination instrument to obtain the connecting inclination angle for each measurement point in the inclined shaft. Among these steps, when using a three-dimensional induction logging instrument for logging, three-dimensional induction logging data with short source distance and high signal strength is preferred for real-time data processing.

[0062] like Figure 2 As shown, the coil system of the three-dimensional induction logging instrument consists of three transmitting coils T, which are centered at a common point and perpendicular to each other. x T y T z Three receiving coils R parallel to it x R y R z (source distance is L1) and three shielding coils B x B y B z Composed of (source distance L2), specifically:

[0063] The coil system of a three-dimensional induction logging instrument includes: three transmitting coils, three receiving coils, and three shielding coils. The centers of the three transmitting coils are at the same point and perpendicular to each other. The centers of the three receiving coils are at the same point and perpendicular to each other. The centers of the three shielding coils are at the same point and perpendicular to each other. The three transmitting coils are denoted as T. x T y and T z The three receiving coils are denoted as coil R. x R y R z The three shielded coils are denoted as B. x B y and B z T x B x and R x Arranged sequentially and collinear, T x With B x The source distance between them is L2, T x With R x B x The source distance between them is L1, T y B y and R y Arranged sequentially and collinear, T y and B y The source distance between them is L2, Ty and R y The source distance between them is L1, T z B z and R z Arranged sequentially and collinear, T z With B z The source distance between them is L2, T z and R z The source distance between them is L1, L1 > L2, T x B x and R x The line T y B y and R y The line and T z B z and R z The line it lies on is parallel.

[0064] When the transmitting coil system emits sinusoidal alternating current into the surrounding environment, it is possible to simultaneously measure nine magnetic field components on the receiving coil system, denoted as H. ij , (i=x,y,z; j=x,y,z), where, H ij H represents the magnetic field strength generated by the emission in direction i and the reception in direction j. Specifically, H xx H represents the magnetic field strength generated by a signal emitted and received in the x-direction. xy H represents the magnetic field strength generated by a signal emitted in the x-direction and received in the y-direction. xz H represents the magnetic field strength generated by a signal emitted in the x-direction and received in the z-direction. yx H represents the magnetic field strength generated by a signal emitted in the y direction and received in the x direction. yy H represents the magnetic field strength generated by a signal emitted and received in the y-direction. yz H represents the magnetic field strength generated by a signal emitted in the y direction and received in the z direction. zx H represents the magnetic field strength generated by a signal emitted in the z-direction and received in the x-direction. zy H represents the magnetic field strength generated by a signal emitted in the z-direction and received in the y-direction. zz It represents the magnetic field strength generated by a signal emitted in the z-direction and received in the z-direction.

[0065] To examine the three-dimensional induction logging response in inclined wells, three coordinate systems need to be introduced: the formation coordinate system OX. f Y f Z f Wellbore coordinate system OX w Y w Z w and instrument coordinate system OX t Y t Zt ,like Figure 3 As shown, the magnetic field tensors in these three coordinate systems satisfy the following rotation transformation rule:

[0066]

[0067] Among them, H w Indicates: the magnetic field strength in the wellbore coordinate system. Represents: R α The inverted matrix, H f H represents the magnetic field strength in the stratigraphic coordinate system. t Indicates: Magnetic field strength in the instrument coordinate system. express: The inverted matrix, α is the wellbore dip angle, defined as the Z-axis in formation coordinates (Z... f ) and the Z-axis in the wellbore coordinate system (Z w The angle between them; The instrument azimuth angle is defined as the angle between the instrument's projection onto the XY plane and the X-axis.

[0068] A shielding coil is introduced to counteract the direct coupling component generated by the transmitting coil in the receiving coil. Direct coupling refers to the induced signal directly induced in the receiving coil by the closed-loop characteristic of magnetic flux without the transmitting signal passing through a ground layer. The shielding coil and the receiving coil have opposite winding directions and unequal number of turns. In air, the direct-coupled electromotive forces generated in the shielding coil and the receiving coil cancel each other out. H ij After compensation (referring to the aforementioned "mutual cancellation of the direct-coupled electromotive forces generated in the shielding coil and the receiving coil in the air"), the magnetic field strength measured by the receiving coil is... It can be expressed by the following formula:

[0069]

[0070] Among them, H ij1 Represents: the magnetic field strength generated by the receiving coil when emitted from direction i and received from direction j, specifically: H xx1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted and received in the x-direction. xy1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted in the x-direction and received in the y-direction. xz1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted in the x-direction and received in the z-direction. yx1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted in the y direction and received in the x direction. yy1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted and received in the y-direction. yz1H represents the magnetic field strength generated by the receiving coil when the signal is emitted in the y direction and received in the z direction. zx1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted in the z-direction and received in the x-direction. zy1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted in the z direction and received in the y direction. zz1 H represents the magnetic field strength generated by the receiving coil when the signal is emitted and received in the z-direction; ij2 Represents: the magnetic field strength generated by the shielding coil when emitted from direction i and received from direction j; specifically, H. xx2 H represents the magnetic field strength generated by the shielding coil when the signal is emitted and received in the x-direction. xy2 H represents the magnetic field strength generated by the shielding coil when emitted in the x-direction and received in the y-direction. xz2 H represents the magnetic field strength generated by the shielding coil when emitted in the x-direction and received in the z-direction. yx2 H represents the magnetic field strength generated by the shielding coil when the signal is emitted in the y direction and received in the x direction. yy2 H represents the magnetic field strength generated by the shielding coil when the signal is emitted and received in the y-direction. yz2 H represents the magnetic field strength generated by the shielding coil when the signal is emitted in the y direction and received in the z direction. zx2 H represents the magnetic field strength generated by the shielding coil when emitted in the z-direction and received in the x-direction. zy2 H represents the magnetic field strength generated by the shielding coil when emitted in the z direction and received in the y direction. zz2 It represents the magnetic field strength generated by the shielding coil when the signal is emitted and received in the z direction.

[0071] To facilitate the comparison between well logging response and formation electrical parameters, it is common to... Measurements converted to the dimension of conductivity Indicates taking The imaginary part, K ij The instrument coefficient of the three-dimensional induction logging instrument is given when the signal is transmitted in the i direction and received in the j direction. ω represents the angular frequency, and μ0 represents the vacuum dielectric constant.

[0072] It should be noted that the above All calculations are performed in the stratigraphic coordinate system.

[0073] The above calculation and The process, known as forward modeling, first involves calculating the electromagnetic field generated by three orthogonal transmitting coils in the formation coordinate system. Then, through coordinate rotation transformation related to the wellbore dip angle α, the three-dimensional induction logging response in the wellbore coordinate system is obtained. Finally, the response is compared with the instrument azimuth angle. The relevant coordinate rotation transformation yields the three-dimensional induction logging response in the instrument coordinate system. Actual logging data is always obtained in the instrument coordinate system. In data processing, it is common practice to obtain the logging response curve in the wellbore coordinate system from the measured data through an inverse transformation of the instrument azimuth angle before further processing.

[0074] S102. Using the inclination angle of the deviated well as the estimated value α0 of the wellbore inclination angle, and setting the range of variation of the wellbore inclination angle, based on the estimated value of the wellbore inclination angle, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of each measurement point of the deviated well, a logging response component combination curve is constructed for each measurement point. The logging response component combination curve includes two curves that are only related to the horizontal conductivity σ. h The curve related to the wellbore dip angle α and the vertical conductivity σ v Irrelevant.

[0075] The range of wellbore inclination angle is (α0-Δα1, α0+Δα2), where α0 represents the estimated value of the wellbore inclination angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value. The values ​​of Δα1 and Δα2 can be the same or different. The continuous inclination angle of the deviated well is used as the estimated value α0 of the wellbore inclination angle. The wellbore inclination angle is continuously taken in (α0-Δα1, α0+Δα2). Combined with the three-dimensional induction logging data of each measurement point, a combination curve of logging response components for each measurement point is constructed.

[0076] The mathematical expression for one of the curves that is only related to horizontal conductivity and wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

[0077] S103. Perform skin effect correction on the two curves corresponding to each measurement point to obtain two corrected curves for each measurement point. Specifically:

[0078] right After performing skin effect correction, the first corrected curve is obtained, denoted as SECσ. HA ,right After performing skin effect correction, the first corrected curve is obtained, denoted as SECσ. HC .

[0079] S104. Obtain the true values ​​of the wellbore dip angle and horizontal conductivity at each measurement point:

[0080] SECσ HA and SECσ HC The intersection point in a uniform TI formation corresponds to the true value α of the wellbore dip angle. True The true value of horizontal conductivity σ h,True In other words, the intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point is determined as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point.

[0081] S105. Based on the true values ​​of the horizontal conductivity and the wellbore inclination angle at each measurement point, calculate the true value of the vertical conductivity at each measurement point. Specifically, obtain the true value α of the wellbore inclination angle. True The true value of horizontal conductivity σ h,True Then, the combined curve (σ) constructed using the cross components is used. zx +σ xz ) Determine the vertical conductivity. Select (σ zx +σ xz The reason is that the response curve becomes flat within the layer and is less affected by adjacent layers. This invention is not limited to using this method to determine the vertical conductivity of the formation; other methods can also be used to calculate the true value of the vertical conductivity at each measurement point.

[0082] The following section uses an 18-layer anisotropic TI formation as an example to illustrate and verify the method of using three-dimensional induction logging data to obtain the electrical conductivity and wellbore dip angle of anisotropic formation in real time. Figure 4 This is a parameter table for an 18-layer anisotropic TI formation model. The transmission frequency of the three-dimensional induction logging instrument is f = 25kHz. The preferred short source-pitch coil system is: main receiving coil source pitch L1 = 30in, shielding coil source pitch L2 = 20.5in, where 1in = 2.54cm.

[0083] Figure 5 It is: the principal component logging response numerical simulation curve obtained by the three-dimensional induction logging instrument at the measurement point with a wellbore inclination angle α = 60°, where the horizontal axis is the vertical measurement depth and the vertical axis is the apparent conductivity of the coil system. Figure 6 It refers to the numerical simulation curves of the cross-component and combined-component logging responses obtained by a three-dimensional induction logging instrument at a measurement point with a wellbore inclination angle α = 60°. From... Figure 6 It can be seen from σzx and σ xz Compared to the curve, (σ) zx +σ xz The curve flattens out within the layer, indicating less influence from adjacent layers. Therefore, in homogeneous anisotropic TI formations, once the horizontal conductivity and wellbore dip angle are determined, solving for the vertical conductivity becomes a single-parameter problem. A response combination (σ) that is less affected by adjacent layers can be selected. zx +σ xz Using this method to determine the vertical conductivity yields better results.

[0084] Figure 7 The text shows the use of... Figure 5 and Figure 6 The combined quantity σ is constructed from the logging response in the well. HA and σ HC After skin effect correction, the combined curve SECσ is obtained. HA and SECσ HC ,from Figure 7 It can be seen from SECσ HA and SECσ HC They can all reconstruct the horizontal conductivity σ of each layer very well. h In other words, their values ​​are very close to the true values ​​of the formation's horizontal conductivity. Then, for each measurement point, the wellbore dip angle is varied within the range of α∈(50°~70°), and the combined quantity SECσ is calculated. HA and SECσ HC By analyzing the two-dimensional intersection diagram, we can find the common solution, which is the formation conductivity and wellbore dip angle.

[0085] Figure 8 It is the combination quantity SECσ HA and SECσ HC α~σ h Two-dimensional cross plot, in a homogeneous TI formation, the combination amount SECσ HA and SECσ HC The x-coordinate of the intersection of the two curves corresponds to the calculated wellbore dip angle, and the y-coordinate corresponds to the calculated horizontal electrical conductivity SECσ of the formation. HA =SECσ HC =σ h Once the horizontal conductivity and wellbore dip angle are determined, a response combination (σ) that is less affected by adjacent layers can be selected. zx +σ xz To determine the vertical conductivity σ v This will yield better results.

[0086] The following tests and analyses examine the anisotropic formation conductivity and wellbore dip angle results obtained using this method under different wellbore dip angles. Figures 10 to 13In this context, psh and psv represent the formation horizontal and vertical conductivity results without considering the influence of noise, while pshN and psvN represent the formation horizontal and vertical conductivity results considering the influence of 5% random noise.

[0087] Figure 9 For example, when the estimated wellbore inclination angle is 60°, the ranges of wellbore inclination angle variation α∈(50°~70°) and α∈(40°~80°) are set, and the real-time processing results of the wellbore inclination angle are obtained under different angle scanning ranges. Figure 9 It can be seen that the smaller the angle scanning range, the more accurate the result. At the same time, it can be seen that increasing the wellbore dip angle scanning range has little impact on the angle calculation result. Figure 10 The parameters are: the formation horizontal and vertical conductivity curves obtained with and without noise when the estimated wellbore dip angle is 60° and the search range is (40°~80°). Figure 11 This refers to the formation horizontal and vertical conductivity curves obtained with and without noise, when the estimated wellbore dip angle is 60° and the search range is (50°~70°). Figure 10 and Figure 11 It can be seen that when the search range of wellbore inclination angle is α∈(40°~80°) and α∈(50°~70°), the obtained formation horizontal and vertical conductivity are very close to the true values ​​of formation horizontal and vertical conductivity. Figure 12 The results are: when the estimated wellbore inclination angle is 30°, and the angle scanning range is (10°~50°), the wellbore inclination angle results are obtained with and without noise.

[0088] Figure 13 It is: when the estimated wellbore inclination angle is 30°, the search range of the wellbore inclination angle is (10°~50°), and the formation horizontal and vertical conductivity curves obtained under noise conditions when the true value of the wellbore inclination angle is 30°.

[0089] Figure 14 Yes: When the estimated wellbore inclination angle is 80°, the wellbore inclination angle results are obtained with and without noise within the angle scanning range (60°~88°).

[0090] Figure 15 It is: when the estimated wellbore dip angle is 80°, the search range of the wellbore dip angle is (60°~88°), and when the true value of the wellbore dip angle is 80°, the formation horizontal conductivity and vertical conductivity curves are obtained under noise conditions.

[0091] from Figure 10 , Figure 11 , Figure 13 and Figure 15As can be seen, the data acquisition method for anisotropic formations in inclined wells of the present invention can calculate the electrical conductivity and wellbore inclination angle of anisotropic formations in real time, and is applicable to the calculation of wellbore inclination angles of any inclined well, such as small angles of 30°, intermediate angles of 60°, and large angles of 80°. Furthermore, even considering random noise, the calculated formation electrical conductivity results match the actual horizontal and vertical electrical conductivity curves of the formation very well.

[0092] In summary, this invention, for each measurement point, utilizes a two-dimensional intersection plot of two constructed three-dimensional induction logging data combination curves to quickly obtain information on the horizontal conductivity, vertical conductivity, and wellbore dip angle of the deviated well formation. Because the method of this invention can obtain the true values ​​of the horizontal and vertical conductivity of the formation in anisotropic TI formation deviated wells with high accuracy, this processing method can accurately identify thin sandstone-mudstone interbedded layers, avoiding the misidentification of such thin interbedded oil reservoirs as high water saturation layers during logging and thus preventing their omission. This is of great significance in logging.

[0093] The beneficial effects of the data acquisition method for anisotropic strata in inclined wells provided by this invention are as follows:

[0094] 1) For each measurement point, it can process the three-dimensional induction logging data of anisotropic formations in deviated wells in real time, and quickly obtain the horizontal conductivity, vertical conductivity and wellbore dip parameters of anisotropic (TI) formation deviated wells. This greatly shortens the logging data processing time, improves the working efficiency of logging instruments, and significantly reduces the cost of testing instruments in the well. It enables three-dimensional induction logging data to be better applied to real-time processing and interpretation evaluation in the field, which is of great significance to the widespread application of three-dimensional induction logging instruments in the field.

[0095] 2) The results of this invention can be applied to the determination of anisotropic TI formation conductivity and wellbore dip angle in any deviated well, especially in highly deviated wells, which broadens the application range of three-dimensional induction logging instruments.

[0096] 3) Since the present invention can obtain the values ​​of horizontal and vertical electrical conductivity of the formation with high accuracy in anisotropic TI formation deviated wells, this processing method can accurately determine the thin sand-mudstone interbedded layer, avoiding the misidentification of such thin interbedded oil reservoirs as high water saturation layers in well logging and thus missing them, which is of great significance in well logging.

[0097] In the above embodiments, although the steps are numbered S1, S2, etc., they are only specific embodiments given by the present invention. Those skilled in the art can adjust the execution order of S1, S2, etc. according to the actual situation, which is also within the protection scope of the present invention. It can be understood that in some embodiments, some or all of the above embodiments may be included.

[0098] like Figure 16 As shown, a data acquisition system 200 for anisotropic formations in a deviated well according to an embodiment of the present invention includes a curve construction module 201, a curve correction module 202, a first truth value determination module 203, and a second truth value determination module 204.

[0099] The curve construction module 201 is used to: take the inclined angle of any measurement point in the deviated well as the estimated value of the wellbore inclination angle of the measurement point, and set the range of variation of the wellbore inclination angle of the measurement point. Based on the estimated value of the wellbore inclination angle of the measurement point, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of the measurement point, construct the logging response component combination curve of the measurement point until the logging response component combination curve of each measurement point is obtained. The logging response component combination curve includes two curves that are only related to the horizontal conductivity and the wellbore inclination angle.

[0100] The curve correction module 202 is used to: perform skin effect correction on the two curves corresponding to each measurement point to obtain two corrected curves corresponding to each measurement point;

[0101] The first truth value determination module 203 is used to: determine the intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point.

[0102] The second truth value determination module 204 is used to: calculate the true value of the vertical conductivity of each measurement point based on the true value of the horizontal conductivity and the true value of the wellbore inclination angle of each measurement point.

[0103] Optionally, in the above technical solution, the range of wellbore inclination angle is: (α0-Δα1, α0+Δα2), where α0 represents the estimated value of wellbore inclination angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value.

[0104] Optionally, the above technical solution also includes a data acquisition module, which is used to: The mathematical expression of one of the curves that is only related to the horizontal conductivity and the wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zxσ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

[0105] It should be noted that the beneficial effects of the data acquisition system 200 for anisotropic formations in inclined shafts provided in the above embodiments are the same as those of the data acquisition method for anisotropic formations in inclined shafts described above, and will not be repeated here. Furthermore, the system provided in the above embodiments is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the system can be divided into different functional modules according to the actual situation to complete all or part of the functions described above. In addition, the system and method embodiments provided in the above embodiments belong to the same concept, and their specific implementation process is detailed in the method embodiments, and will not be repeated here.

[0106] like Figure 17 As shown, an electronic device 300 according to an embodiment of the present invention includes a processor 320 coupled to a memory 310. The memory 310 stores at least one computer program 330, which is loaded and executed by the processor 320 to enable the electronic device 300 to implement any of the above-mentioned methods for acquiring data from anisotropic formations within a deviated well. Specifically:

[0107] The electronic device 300 can vary considerably due to differences in configuration or performance. It may include one or more processors 320 (Central Processing Units, CPUs) and one or more memories 310. The memories 310 store at least one computer program 330, which is loaded and executed by the processors 320 to enable the electronic device 300 to implement any of the data acquisition methods for anisotropic formations within inclined shafts provided in the above embodiments. Of course, the electronic device 300 may also have wired or wireless network interfaces, a keyboard, and input / output interfaces for input and output. It may also include other components for implementing device functions, which will not be elaborated here. Specifically, the electronic device may be a computer, etc.

[0108] An embodiment of the present invention provides a computer-readable storage medium storing at least one computer program, which is loaded and executed by a processor to enable a computer to implement any of the above-described methods for acquiring data from anisotropic formations within a deviated well.

[0109] Alternatively, the computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), magnetic tape, a floppy disk, and an optical data storage device, etc.

[0110] In an exemplary embodiment, a computer program product or computer program is also provided, which includes computer instructions stored in a computer-readable storage medium. A processor of an electronic device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the electronic device to perform any of the above-described methods for acquiring data from anisotropic formations within a deviated well.

[0111] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and represent a limitation on a specific order or sequence. Where appropriate, the order of use for similar objects can be interchanged so that the embodiments of this application described herein can be implemented in an order other than that shown or described.

[0112] Those skilled in the art will recognize that this invention can be implemented as a system, method, or computer program product. Therefore, this invention can be specifically implemented in the following forms: it can be entirely hardware, entirely software (including firmware, resident software, microcode, etc.), or a combination of hardware and software, generally referred to herein as a "circuit," "module," or "system." Furthermore, in some embodiments, this invention can also be implemented as a computer program product contained in one or more computer-readable media, which includes computer-readable program code.

[0113] Any combination of one or more computer-readable media can be used. A computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this invention, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0114] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for acquiring data from anisotropic formations within an inclined shaft, characterized in that, include: The inclination angle of any measurement point in the deviated well is used as the estimated value of the wellbore inclination angle of that measurement point, and the range of variation of the wellbore inclination angle of that measurement point is set. Based on the estimated value of the wellbore inclination angle of that measurement point, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of that measurement point, the logging response component combination curve of that measurement point is constructed until the logging response component combination curve of each measurement point is obtained. The logging response component combination curve includes two curves that are only related to the horizontal conductivity and the wellbore inclination angle. Skin effect correction is performed on the two curves corresponding to each measurement point to obtain two corrected curves for each measurement point. The intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point is determined as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point. The true value of the vertical conductivity at each measurement point is calculated based on the true value of the horizontal conductivity and the true value of the wellbore inclination angle at each measurement point.

2. The method for acquiring data from anisotropic formations within an inclined shaft according to claim 1, characterized in that, The range of wellbore dip angle is: (α0-Δα1, α0+Δα2), where α0 represents the estimated value of the wellbore dip angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value.

3. A method for acquiring data from anisotropic formations within an inclined shaft according to claim 1 or 2, characterized in that, Also includes: Three-dimensional induction logging instruments are used to log in the inclined shaft to obtain three-dimensional induction logging data for each measurement point in the inclined shaft. Inclination connection instruments are used to log in the inclined shaft to obtain the inclination connection angle for each measurement point in the inclined shaft.

4. The method for acquiring data from anisotropic formations within an inclined shaft according to claim 2, characterized in that, The mathematical expression for one of the curves that is only related to horizontal conductivity and wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

5. A data acquisition system for anisotropic formations within an inclined shaft, characterized in that, It includes a curve construction module, a curve correction module, a first truth value determination module, and a second truth value determination module; The curve construction module is used to: take the inclination angle of any measurement point in the deviated well as the estimated value of the wellbore inclination angle of that measurement point, and set the range of variation of the wellbore inclination angle of that measurement point. Based on the estimated value of the wellbore inclination angle of that measurement point, the range of variation of the wellbore inclination angle, and the three-dimensional induction logging data of that measurement point, construct the logging response component combination curve of that measurement point, until the logging response component combination curve of each measurement point is obtained. The logging response component combination curve includes two curves that are only related to the horizontal conductivity and the wellbore inclination angle. The curve correction module is used to: perform skin effect correction on the two curves corresponding to each measurement point to obtain two corrected curves corresponding to each measurement point; The first truth value determination module is used to: determine the intersection point of the two corrected curves in the two-dimensional intersection diagram corresponding to each measurement point as the true value of the wellbore dip angle and the true value of the horizontal conductivity of the corresponding measurement point; The second truth value determination module is used to calculate the true value of the vertical conductivity of each measurement point based on the true value of the horizontal conductivity and the true value of the wellbore inclination angle of each measurement point.

6. The data acquisition system for anisotropic formations within an inclined shaft according to claim 5, characterized in that, The range of wellbore dip angle is: (α0-Δα1, α0+Δα2), where α0 represents the estimated value of the wellbore dip angle, Δα1 represents the first preset angle value, and Δα2 represents the second preset angle value.

7. A data acquisition system for anisotropic formations within an inclined shaft according to claim 5 or 6, characterized in that, It also includes a data acquisition module, which is used to: perform logging in the inclined shaft using a three-dimensional induction logging instrument to obtain three-dimensional induction logging data for each measurement point in the inclined shaft, and perform logging in the inclined shaft using a connecting inclination instrument to obtain the connecting inclination angle for each measurement point in the inclined shaft.

8. A data acquisition system for anisotropic formations within an inclined shaft according to claim 6, characterized in that, The mathematical expression for one of the curves that is only related to horizontal conductivity and wellbore dip angle is: The mathematical expression for another curve that is only related to horizontal conductivity and wellbore dip angle is: Where α represents the wellbore dip angle, σ zz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the z-direction. xx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission and reception in the x-direction. xz σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the x-direction and reception in the z-direction. zx σ represents the apparent conductivity calculated from the magnetic field strength generated by the emission in the z-direction and the reception in the x-direction. HA Indicates: through The horizontal conductivity, σ, is calculated. HC Indicates: through The calculated horizontal conductivity.

9. An electronic device, characterized in that, The electronic device includes a processor coupled to a memory, the memory storing at least one computer program, which is loaded and executed by the processor to enable the electronic device to implement a data acquisition method for anisotropic formations in a deviated well as described in any one of claims 1 to 4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one computer program, which is loaded and executed by a processor to enable the computer to implement a data acquisition method for anisotropic formations in a deviated well as described in any one of claims 1 to 4.

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