A method for predicting depth while drilling based on comprehensive electrical response of sedimentary filling rocks

Abstract

The invention discloses a method for predicting depth while drilling based on the comprehensive response of sedimentary filling rock electricity. The method comprehensively analyzes the regional stratum sedimentary filling law and rock electricity characteristics, combines the velocity model established under the drive of seismic data, introduces the improved Faust statistical relationship formula, constructs the acoustic wave curve using the resistivity curve, and judges the stratum lithology according to various curves during the drilling process. The method timely adopts the method of integrating various information responses such as phase-controlled constant velocity estimation to predict the depth while drilling, accurately controls the stratum velocity, locates the drill bit position and predicts the depth of the target layer, provides the accurate casing lowering depth, ensures the smooth drilling, and effectively solves the technical problem that the prior art cannot accurately predict the depth while drilling in deep water areas.

Description

Technical Field

[0001] The present invention relates to the technical field of geological exploration, and more specifically, to a method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks. Background Art

[0002] In the actual drilling process, when drilling to a critical position, it is necessary to timely determine the current bottom hole position and determine the lithology of the formation below the bottom hole position, and then adjust the drilling fluid density and drilling technology in subsequent drilling. Therefore, it is very important to determine the formation during the drilling process.

[0003] The prior art discloses a method for determining formations during drilling, wherein the drilling process includes a drilled portion and an undrilled portion, wherein the drilled portion includes a logged section and an unlogged section, and the method for determining formations includes: (1) establishing a three-dimensional map representing the relationship between depth, drilling time, and formation velocity for different lithologies at different depths according to the drilling time and formation velocity corresponding to different lithologies at different depths in adjacent drilled wells; (2) obtaining the lithology and drilling time corresponding to different depths of the unlogged section, and obtaining the formation velocity corresponding to different depths of the unlogged section according to the three-dimensional map of step (1), and obtaining the formation density corresponding to different depths of the unlogged section. ; (3) obtaining the formation velocity and formation density of the measured section; (4) using the formation velocity of the measured section obtained in step (3) and the formation velocities corresponding to different depths of the unmeasured section obtained in step (2) as the formation velocity data of the drilled portion of the well being drilled, and using the formation density of the measured section obtained in step (3) and the formation density corresponding to different depths of the unmeasured section obtained in step (2) as the formation density data of the drilled portion of the well being drilled; using the formation velocity data and the formation density data to obtain a synthetic seismic record corresponding to the drilled portion of the well being drilled; and determining the formation lithology of the undrilled portion based on the synthetic seismic record.

[0004] However, the existing technologies mainly use velocity models established under the drive of seismic data or a relatively simple method of time-depth relationship of drilled wells to predict the depth of exploration wells before drilling and while drilling. These methods have large prediction errors for complex geological conditions in deepwater areas. In addition, due to the impact of drilling costs, acoustic wave and density logging curves are often lacking during the drilling process. Traditional acoustic wave estimation methods are mainly based on theoretical models of rock physics or empirical formulas based on porosity-mud content, which are not suitable for real-time depth prediction of target layers during drilling. Therefore, there is a technical problem in the existing technologies that it is impossible to accurately predict the depth of deepwater areas while drilling. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiency of the prior art that the drilling depth in deep water areas cannot be accurately predicted, and to provide a method for predicting the drilling depth based on the comprehensive electrical response of sedimentary filling rocks.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks comprises the following steps:

[0008] S1. Analyze the sedimentation and filling evolution process of the basin, and clarify the lithological characteristics and rock-electric response characteristics of different strata;

[0009] S2. Construct the acoustic wave curve of the mud-rich section based on the improved Faust statistical relationship of regional parameters;

[0010] 21) Calculate the longitudinal wave velocity of rock through the physical properties of rock;

[0011] 22) Calculate the resistivity of rock through the porosity of rock and pore fluid;

[0012] 23) Establish the statistical relationship between the longitudinal wave velocity of rock and the resistivity of rock, and perform well seismic calibration;

[0013] S3. Prediction of formation velocity using the constant velocity stripping method based on sedimentation and filling constraints;

[0014] 31) Based on the understanding of sedimentary filling evolution, different source-reservoir areas are divided and the distribution sections and distribution areas of the marker layers are described;

[0015] 32) Find the marker layer through the relative relationship between the source and reservoir areas, and combine the drilling speed information and resistivity response to determine whether the marker layer has been drilled and the location of the marker layer on the corresponding well;

[0016] 33) Based on the constant speed stripping method with sedimentation and filling constraints, the velocity of the formation to be drilled below the drill bit is predicted, and then the depth of the formation to be drilled is predicted.

[0017] The invention discloses a method for predicting depth while drilling based on comprehensive response of sedimentation and filling rock electricity. The method takes the problem of predicting depth while drilling in complex geological conditions in deepwater exploration areas, such as rugged seabed, large vertical and horizontal changes in formation velocity, and missing acoustic logging curves, as the research object. The method comprehensively analyzes the regional formation sedimentation and filling laws and rock electricity characteristics, combines the velocity model established under the drive of seismic data, introduces the improved Faust statistical relationship formula to construct acoustic wave curves using resistivity curves, and judges the formation lithology according to various curves during the drilling process. The method adopts the method of integrating various information responses such as phase-controlled constant velocity estimation to predict depth while drilling accurately, control the formation velocity, locate the drill bit position, and predict the depth of the target layer, provide accurate casing lowering depth, ensure smooth drilling, and effectively solve the technical problem that the existing technology cannot accurately predict the depth while drilling in deepwater areas.

[0018] Further, step S1 specifically includes: comprehensively analyzing the properties of the basin sedimentary source area, hydrodynamic conditions, and diagenetic field characteristics, characterizing the sedimentary facies belt, dividing the vertical segmentation and lateral distribution areas of different source-reservoir properties, identifying the lithology of different source-reservoir formations and the corresponding rock-electric response characteristics, and combining the formation velocity model obtained by inversion of seismic data to give the initial velocity along the trajectory to be drilled. Identify the corresponding box-shaped sand or bell-shaped sand in the gamma curve, the resistivity curve showing obvious peaks in the ash-bearing formation, and the acoustic wave curve showing low values ​​in the reservoir with better physical properties, so as to clarify the rock-electric response of the iconic formation.

[0019] Furthermore, in step 21), the formula for calculating the longitudinal wave velocity of the rock using the elastic modulus, porosity and pore fluid properties of the rock is:

[0020]

[0021]

[0022]

[0023] Where K d and K m are the bulk moduli of the rock skeleton and rock matrix, is the rock porosity, μ m and μ d Corresponding to the shear modulus of rock matrix and rock skeleton, K f is the bulk modulus of the fluid saturated at the corresponding position underground in the work area, μ s is the shear modulus of the saturated fluid, ρ s is the density value obtained from well logging, V p Represents the longitudinal wave velocity value of the rock.

[0024] Further, in step 22), the formula for calculating the resistivity of the rock using the porosity of the rock and the pore fluid is: Where R t is the resistivity value of fully saturated rock, R w is the resistivity of pore fluid, S w is the saturation, n is the saturation index, and m is the adhesion index.

[0025] Further, in step 23), the statistical relationship between the formation resistivity curve and the acoustic wave curve of similar source-reservoir areas under the same sedimentary and diagenetic field environment is used to establish the Faust statistical relationship formula based on regional parameters: V sonic =A rock ×log 10 (RT)+B rock , where V sonicis the acoustic wave velocity, RT is the resistivity value, and the correction factor A rock and the regularization parameter B rock The resistivity and acoustic wave curves of neighboring wells with good resistivity under the same sedimentary environment can be selected and fitted using the Faust statistical relationship formula. Most of the minerals that make up the rock are semiconductors and insulators, so the properties and saturation of the fluid in the rock have a greater impact on the resistivity than the acoustic wave. The fluid properties in sandstone are relatively complex, which will have a stronger impact on the resistivity. For mudstone, it contains very little fluid and the resistivity value is relatively stable, so this formula is more accurate for constructing the acoustic wave curve for the mudstone section.

[0026] Further, step 31) is specifically as follows: by performing lateral comparison of the drilled marker layer, analyzing and obtaining the disturbance velocity δV of the regional marker layer, combining the distribution law of the marker layer based on the recognition of the characteristic distribution of the source-reservoir area, identifying and determining the seismic phase characteristics of the marker layer.

[0027] Furthermore, step 32) is specifically as follows: during the drilling process, the logging lithology, drilling speed information and gamma, resistivity and other response characteristics are integrated to determine whether the marker layer and the development position of the marker layer on the corresponding well are drilled, and the disturbance velocity δV of the marker layer is given in combination with the regional drilling marker layer velocity data, and then the logging lithology, resistivity curve and corresponding marker layer seismic phase characteristics are integrated to accurately locate the marker layer position for time-depth calibration.

[0028] Furthermore, in step 33), after the time-depth calibration of the drilled formation, the time-depth relationship formula of the drilled formation is obtained by integrating the logging lithology, drilling speed information, gamma, resistivity and other information responses: T = f(V sonic , Z), where T is the two-way travel time of the time domain earthquake corresponding to the drill bit depth, V sonic is the speed of sound waves, and Z is the depth of the drill bit above sea level during drilling.

[0029] Further, in step 33), the velocity formula of the drilled formation is obtained by integrating the time-depth relationship of the drilled formation: V aver =2Z / T, where Z is the depth of the drill bit above sea level while drilling, T is the two-way travel time of the time domain seismic corresponding to the drill bit depth, V aver It is the average velocity of the drilled formation after calibration.

[0030] Further, in step 33), the time-depth relationship of the drilled formation and the velocity of the drilled formation are combined to obtain the formula for the depth of the formation to be drilled: Where V aver is the average velocity of the drilled formation after calibration, δV is the disturbance velocity generated by the marker layer, T target and Z target are the round-trip travel time and depth of the formation to be drilled, respectively.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The invention discloses a method for predicting depth while drilling based on the comprehensive response of sedimentary filling rock electricity. The method comprehensively analyzes the regional stratum sedimentary filling law and rock electricity characteristics, combines the velocity model established under the drive of seismic data, introduces the improved Faust statistical relationship formula, constructs the acoustic wave curve using the resistivity curve, and judges the stratum lithology according to various curves during the drilling process. The method timely adopts the method of integrating various information responses such as phase-controlled constant velocity estimation to predict the depth while drilling, accurately controls the stratum velocity, locates the drill bit position and predicts the depth of the target layer, provides the accurate casing lowering depth, ensures the smooth drilling, and effectively solves the technical problem that the prior art cannot accurately predict the depth while drilling in deep water areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a flowchart of a method for predicting the depth while drilling based on the comprehensive electrical response of sedimentary filling rocks;

[0034] Figure 2 This is the Faust statistical relationship curve improved according to the parameters of the deepwater Baodao area in the Qiongdongnan Basin in the northern South China Sea;

[0035] Figure 3 This is a comparison chart of the actual drilling velocity curve and the initial velocity curve of the X-7d well. DETAILED DESCRIPTION

[0036] The present invention is further described below in conjunction with specific implementation methods. The accompanying drawings are only used for exemplary descriptions and are only schematic diagrams, not actual drawings, and cannot be understood as limiting this patent; in order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the accompanying drawings may be omitted.

[0037] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0038] Embodiment 1

[0039] like Figure 1The figure shows the first embodiment of a method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks according to the present invention.

[0040] A method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks comprises the following steps:

[0041] S1. Analyze the sedimentation and filling evolution process of the basin, and clarify the lithological characteristics and rock-electric response characteristics of different strata;

[0042] S2. Construct the acoustic wave curve of the mud-rich section based on the improved Faust statistical relationship of regional parameters;

[0043] 21) Calculate the longitudinal wave velocity of rock through the physical properties of rock;

[0044] 22) Calculate the resistivity of rock through the porosity of rock and pore fluid;

[0045] 23) Establish the statistical relationship between the longitudinal wave velocity of rock and the resistivity of rock, and perform well seismic calibration;

[0046] S3. Prediction of formation velocity using the constant velocity stripping method based on sedimentation and filling constraints;

[0047] 31) Based on the understanding of sedimentary filling evolution, different source-reservoir areas are divided and the distribution sections and distribution areas of the marker layers are described;

[0048] 32) Find the marker layer through the relative relationship between the source and reservoir areas, and combine the drilling speed information and resistivity response to determine whether the marker layer has been drilled and the location of the marker layer on the corresponding well;

[0049] 33) Based on the constant speed stripping method with sedimentation and filling constraints, the velocity of the formation to be drilled below the drill bit is predicted, and then the depth of the formation to be drilled is predicted.

[0050] In this embodiment, if Figure 1 As shown in the figure, the problem of depth prediction while drilling in the complex geological conditions of deepwater exploration areas, such as rugged seabed, large vertical and horizontal changes in formation velocity, and missing acoustic logging curves, is taken as the research object. The regional formation sedimentary filling rules and rock electrical characteristics are comprehensively analyzed, and the velocity model established under the drive of seismic data is combined. The improved Faust statistical relationship formula is introduced to construct the acoustic curve using the resistivity curve. In the process of drilling, the lithology of the formation is judged according to various curves. The depth prediction while drilling is carried out in a way of integrating various information responses such as phase-controlled constant velocity estimation. The formation velocity is accurately controlled, the drill bit position is located, and the depth of the target layer is predicted. The accurate casing lowering depth is provided to ensure smooth drilling, which effectively solves the technical problem that the existing technology cannot accurately predict the depth while drilling in deepwater areas.

[0051] Among them, step S1 specifically includes: comprehensively analyzing the properties of the basin sedimentary source area, hydrodynamic conditions, and diagenetic field characteristics, characterizing the sedimentary facies belt, dividing the vertical segmentation and lateral distribution areas of different source-reservoir properties, identifying the lithology of different source-reservoir formations and the corresponding rock-electric response characteristics, combining the formation velocity model obtained by inversion of seismic data, and giving the initial velocity along the trajectory to be drilled.

[0052] In this embodiment, the corresponding box-shaped sand or bell-shaped sand in the gamma curve, the resistivity curve showing obvious peaks in the ash-containing strata, and the acoustic wave curve showing low values ​​in the good reservoir properties are identified, thereby clarifying the rock electrical response of the iconic strata.

[0053] Embodiment 2

[0054] like Figure 2 The figure shows a second embodiment of a method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks according to the present invention.

[0055] This embodiment is similar to the first embodiment, except that in step 21), the formula for calculating the longitudinal wave velocity of the rock using the elastic modulus, porosity and pore fluid properties of the rock is:

[0056]

[0057]

[0058]

[0059] Where K d and K m are the bulk moduli of the rock skeleton and rock matrix, is the rock porosity, μ m and μ d Corresponding to the shear modulus of rock matrix and rock skeleton, K f is the bulk modulus of the fluid saturated at the corresponding position underground in the work area, μ s is the shear modulus of the saturated fluid, ρ s is the density value obtained from well logging, V p Represents the longitudinal wave velocity value of the rock. Wherein, in step 22), the formula for calculating the resistivity of the rock using the porosity of the rock and the pore fluid is: Where R t is the resistivity value of fully saturated rock, R w is the resistivity of pore fluid, S wis saturation, n is saturation index, and m is cementation index. In step 23), the statistical relationship between the formation resistivity curve and the acoustic wave curve of similar source-reservoir areas under the same sedimentary and diagenetic field environment is used to establish the Faust statistical relationship formula based on regional parameters: V sonic =A rock ×log 10 (RT)+B rock , where V sonic is the acoustic wave velocity, RT is the resistivity value, and the correction factor A rock and the regularization parameter B rock It can be obtained by selecting the better resistivity and acoustic wave curves of adjacent wells under the same sedimentary environment and fitting them using the Faust statistical relationship formula.

[0060] In this embodiment, most of the minerals that make up the rock are semiconductors and insulators, so the properties and saturation of the fluid in the rock have a greater impact on the resistivity than the sound wave. The fluid properties in sandstone are relatively complex and will have a stronger impact on the resistivity. For mudstone, it contains very little fluid and the resistivity value is relatively stable. Therefore, this formula is more accurate for constructing the sound wave curve for the mudstone section.

[0061] In addition, in this embodiment, a method for predicting depth while drilling based on the comprehensive response of sedimentary filling rock electricity in this embodiment can be applied to the exploration of the deepwater Baodao X area in the Qiongdongnan Basin in the northern South China Sea. The seabed in the deepwater area of ​​the western South China Sea is rugged, the water depth is about 1200m, and the formation velocity varies greatly in the vertical and horizontal directions. During the drilling of the X-7d well in this area, only gamma and resistivity logging while drilling were performed, and there was no acoustic wave and density curve. The test process is as follows:

[0062] In the pre-drilling design stage, the P-wave velocity ratio and P-wave impedance obtained by pre-stack AVO inversion are combined with the lithology of adjacent wells and the seismic velocity model to comprehensively analyze and fit the pre-drilling predicted time-depth relationship; from the regional sedimentary filling background and pre-stack inversion, it can be seen that the target layer as a whole shows high P-wave impedance and high P-wave velocity ratio response, which is predicted to be a large set of mudstone characteristics, and there are thin sand layers locally, which meets the conditions of the Faust statistical relationship formula in this embodiment. Therefore, during the drilling process, the acoustic wave curve can be constructed according to the Faust statistical relationship formula improved by the target area parameters for prediction;

[0063] During the drilling process, the shallow strata are calibrated using logging lithology and seismic velocity bodies to preliminarily determine the drill bit position and the predicted depth of the target layer. The target layer is covered by a thick mud-rich stratum, such as Figure 2As shown, the Faust statistical relationship improved by the target area parameters is used to construct the acoustic wave curve for time-depth calibration using the resistivity curve. The blue points are the measured data points, and the red line is a curve obtained by fitting the blue points using a logarithmic relationship. The position where the velocity of the fitted acoustic wave curve increases significantly corresponds to a set of gray sandstone top surfaces, which is in line with the regional geological laws, confirms the accuracy of the Faust statistical relationship formula, and shows that a relationship can be established between velocity and resistivity. Subsequently, the acoustic wave curve can be obtained through the resistivity curve, which confirms that the downhole depth prediction method based on the comprehensive electrical response of sedimentary filling rocks in this embodiment has high actual prediction time-depth accuracy, can accurately control the formation velocity, locate the drill bit position and predict the target layer depth, provide accurate casing lowering depth, and control the depth error between the predicted formation and the actual drilled formation within 10m, ensuring smooth drilling and obtaining better gas layer discovery.

[0064] Embodiment 3

[0065] like Figure 3 The third embodiment of the present invention is a method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks.

[0066] This embodiment is similar to the first embodiment or the second embodiment, except that: Step 31) is specifically as follows: by performing a lateral comparison with the drilled marker layer, analyzing and obtaining the disturbance velocity δV of the regional marker layer, and combining the distribution law of the marker layer based on the distribution of the source-reservoir characteristics, the seismic phase characteristics of the marker layer are identified and determined. Wherein, step 32) is specifically as follows: during the drilling process, the logging lithology, drilling speed information, gamma, resistivity and other response characteristics are integrated to determine whether the marker layer and the development position of the marker layer on the corresponding well are drilled, and the disturbance velocity δV of the marker layer is given in combination with the regional drilling marker layer velocity data, and then the logging lithology, resistivity curve and the corresponding marker layer seismic phase characteristics are integrated to accurately locate the marker layer position for time-depth calibration. Wherein, in step 33), after the time-depth calibration of the drilled formation is performed, the logging lithology, drilling speed information, gamma, resistivity and other information responses are integrated to obtain the time-depth relationship formula of the drilled formation: T=f(V sonic , Z), where T is the two-way travel time of the time domain earthquake corresponding to the drill bit depth, V sonic is the acoustic wave velocity, and Z is the altitude depth of the drill bit during drilling. In step 33), the velocity formula of the drilled formation is obtained by integrating the time-depth relationship of the drilled formation: V aver =2Z / T, where Z is the depth of the drill bit above sea level while drilling, T is the two-way travel time of the time domain seismic corresponding to the drill bit depth, V aver is the average velocity of the drilled formation after calibration. Wherein, in step 33), the formula for the depth of the formation to be drilled is obtained by combining the time-depth relationship of the drilled formation and the velocity of the drilled formation: Where V averis the average velocity of the drilled formation after calibration, δV is the disturbance velocity generated by the marker layer, T target and Z target are the round-trip travel time and depth of the formation to be drilled, respectively.

[0067] In addition, in this embodiment, a method for predicting depth while drilling based on the comprehensive response of sedimentary filling rock electricity in this embodiment can be applied to the exploration of the deepwater Baodao X area in the Qiongdongnan Basin in the northern South China Sea. When drilling into a section with complex fluidity (such as when there is a gas logging display), the Faust statistical relationship of regional parameters is no longer applicable. Therefore, it is necessary to combine sedimentary filling and the corresponding velocity body to comprehensively predict the time-depth and give the predicted depth of the target layer. The strata below 4200m of the X-7d well in this area are delta deposits. Affected by the source area, ash-bearing reservoirs may be encountered. The specific drilling process is as follows:

[0068] like Figure 3 As shown, the ordinate of each column is time, the abscissa of the first column is depth, the abscissa of the second column is layer velocity, the abscissa of the third column is average velocity, the abscissa of the fourth column is root mean square velocity, the red curve is the actual drilling velocity curve, the blue is the initial velocity curve, the layer velocity of the second column reflects the velocity change between different layers, and the third and fourth columns can be combined to reflect the rationality of the overall time-depth relationship; after drilling to 4400m, the drilling speed dropped sharply and the resistance increased significantly. When drilling into the high-speed reservoir containing ash, the constant-speed stripping method based on the regional ash reservoir seismic phase characteristics and sedimentary filling constraints was used to give a layer velocity of about 4424m / s for the ash-containing reservoir for depth prediction. The predicted depth of the target layer to be drilled is within 10m of the actual drilling revelation. The time depth is calibrated by subsequent cable supplementary measurement of acoustic waves and density curves, which is basically consistent with the speed updated in real time during the drilling process. Therefore, a method for predicting the depth while drilling based on the comprehensive response of sedimentary filling rock electricity in this embodiment can ensure the smooth and safe completion of the drilling operation and successfully realize the discovery of gas layers.

[0069] In the specific contents of the above-mentioned specific implementation methods, the various technical features can be combined in any non-contradictory manner. In order to make the description concise, not all possible combinations of the above-mentioned technical features are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rocks, characterized in that: The following steps are involved: S1. Analyze the sedimentation and filling evolution process of the basin, and clarify the lithological characteristics and rock-electric response characteristics of different strata; S2. Construct the acoustic wave curve of the mud-rich section based on the improved Faust statistical relationship of regional parameters; 21) Calculate the longitudinal wave velocity of rock through the physical properties of rock; 22) Calculate the resistivity of rock through the porosity of rock and pore fluid; 23) Establish the statistical relationship between the longitudinal wave velocity of rock and the resistivity of rock, and perform well seismic calibration; S3. Prediction of formation velocity using the constant velocity stripping method based on sedimentation and filling constraints; 31) Based on the understanding of sedimentary filling evolution, different source-reservoir areas are divided and the distribution sections and distribution areas of the marker layers are described; 32) Find the marker layer through the relative relationship between the source and reservoir areas, and combine the drilling speed information and resistivity response to determine whether the marker layer has been drilled and the location of the marker layer on the corresponding well; 33) Based on the constant speed stripping method with sedimentation and filling constraints, the velocity of the formation to be drilled below the drill bit is predicted, and then the depth of the formation to be drilled is predicted; In step 21), the formula for calculating the longitudinal wave velocity of the rock using the elastic modulus, porosity and pore fluid properties of the rock is: Where K d and K m are the bulk moduli of the rock skeleton and rock matrix, is the rock porosity, μ m and μ d Corresponding to the shear modulus of rock matrix and rock skeleton, K f is the bulk modulus of the fluid saturated at the corresponding position underground in the work area, μ s is the shear modulus of the saturated fluid, ρ s is the density value obtained from well logging, V p Represents the longitudinal wave velocity value of the rock.

2. The method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 1 is characterized in that: Step S1 specifically includes: comprehensively analyzing the properties of the basin's sedimentary source area, hydrodynamic conditions, and diagenetic field characteristics, characterizing the sedimentary facies belt, dividing the vertical segmentation and lateral distribution areas of different source-reservoir properties, identifying the lithology of different source-reservoir formations and the corresponding rock-electric response characteristics, combining the formation velocity model obtained by inversion of seismic data, and giving the initial velocity along the trajectory to be drilled.

3. The method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 1 is characterized in that: In step 22), the formula for calculating the resistivity of the rock using the porosity of the rock and the pore fluid is: Where R t is the resistivity value of fully saturated rock, R w is the resistivity of pore fluid, S w is the saturation, n is the saturation index, and m is the adhesion index.

4. The method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 3 is characterized in that: In step 23), the statistical relationship between the formation resistivity curve and the acoustic wave curve of similar source-reservoir areas under the same sedimentary and diagenetic environment is used to establish the Faust statistical relationship formula based on regional parameters: V sonic =A rock ×log 10 (RT)+B rock , where V sonic is the acoustic wave velocity, RT is the resistivity value, and the correction factor A rock and the regularization parameter B rock The resistivity and acoustic wave curves of adjacent wells with better resistivity in the same sedimentary environment are selected and fitted using the Faust statistical relationship formula.

5. The method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 4 is characterized in that: Step 31) is specifically as follows: by performing lateral comparison of the drilled marker layer, analyzing and obtaining the disturbance velocity δV of the regional marker layer, combining the distribution law of the marker layer based on the recognition of the characteristic distribution of the source-reservoir area, identifying and determining the seismic phase characteristics of the marker layer.

6. A method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 5, characterized in that: Step 32) is specifically as follows: during the drilling process, the logging lithology, drilling speed information, gamma and resistivity response characteristics are integrated to determine whether the marker layer and the development position of the marker layer on the corresponding well are drilled, and the disturbance velocity δV of the marker layer is given in combination with the regional marker layer velocity data. Then, the logging lithology, resistivity curve and seismic phase characteristics of the corresponding marker layer are integrated to accurately locate the marker layer position for time-depth calibration.

7. A method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 6, characterized in that: In step 33), after the time-depth calibration of the drilled formation, the time-depth relationship formula of the drilled formation is obtained by integrating the logging lithology, drilling speed information, gamma, resistivity and other information responses: T = f(V sonic , Z), where T is the two-way travel time of the time domain earthquake corresponding to the drill bit depth, V sonic is the speed of sound waves, and Z is the depth of the drill bit above sea level during drilling.

8. The method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 7, characterized in that: In step 33), the velocity formula of the drilled formation is obtained by integrating the time-depth relationship of the drilled formation: V aver =2Z / T, where Z is the depth of the drill bit above sea level while drilling, T is the two-way travel time of the time domain seismic corresponding to the drill bit depth, V aver It is the average velocity of the drilled formation after calibration.

9. The method for predicting depth while drilling based on the comprehensive electrical response of sedimentary filling rock according to claim 8, characterized in that: In step 33), the time-depth relationship of the drilled formation and the velocity of the drilled formation are combined to obtain the formula for the depth of the formation to be drilled: Where V aver is the average velocity of the drilled formation after calibration, δV is the disturbance velocity generated by the marker layer, T target and Z target are the round-trip travel time and depth of the formation to be drilled, respectively.

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