Method and device for determining formation overpressure category during drilling

Abstract

An embodiment of the present invention discloses a method and device for determining the formation overpressure category during drilling. Among them, the method includes: determining the change trend of the organic carbon content of each mudstone sample in the first-depth formation according to the rock pyrolysis logging data of each mudstone sample in the first-depth formation of the drilled section during drilling, and determining the change trend of the maximum cracking peak parameter of kerogen of each mudstone sample in the first-depth formation; wherein, the number of mudstone samples in the first-depth formation is at least one; the first-depth formation is an overpressure formation; determining the formation overpressure category in the first-depth formation of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameter of kerogen. By implementing the technical solution provided by the embodiment of the present invention, it is possible to determine the formation overpressure type in real time during drilling, improve the accuracy of formation pressure monitoring while drilling, promote the oil and gas exploration process, and improve the resource development efficiency.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of pressure measurement while drilling, and in particular, to a method and device for determining the formation overpressure category during the drilling process. Background Art

[0002] As oil and gas exploration gradually moves towards deeper layers and the deep sea, the situations of drilling failure or out-of-control blowout caused by sudden formation overpressure during drilling are endless. The former will result in losses to the exploration investment of operators, and the latter often causes adverse consequences such as personnel and property losses, environmental pollution, etc.

[0003] In actual drilling operations, timely and effective pressure monitoring of the formation while drilling is an important basis for ensuring drilling safety. If the causes of overpressure can be objectively identified in a timely manner, the accuracy of pressure monitoring of the formation while drilling will be significantly improved, which is also conducive to promoting the process of oil and gas exploration and enhancing the efficiency of resource development.

[0004] In the formation overpressure cause discrimination methods in the related art, the application scenarios are lagging. The relevant data required in the overpressure cause discrimination methods need to be obtained after the drilling is completed, with poor timeliness, and it is impossible to determine the types of formation overpressure during the drilling process. Summary of the Invention

[0005] The embodiments of the present invention provide a method and device for determining the formation overpressure category during the drilling process, which can realize the real-time determination of the formation overpressure type during the drilling process, improve the accuracy of pressure monitoring of the formation while drilling, promote the process of oil and gas exploration, and enhance the efficiency of resource development.

[0006] In a first aspect, the embodiments of the present invention provide a method for determining the formation overpressure category during the drilling process, and the method includes:

[0007] Determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section during the drilling process, and determine the change trend of the maximum cracking peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section; wherein, the number of mudstone samples in the first-depth formation of the drilled section is at least one; the first-depth formation of the drilled section is an overpressure formation;

[0008] Determine the formation overpressure category in the first-depth formation of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameter of the kerogen.

[0009] Second aspect, an embodiment of the present invention further provides a device for determining the formation overpressure category during drilling. The device includes: a variation trend determination module, configured to determine the variation trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section during drilling according to the rock pyrolysis logging data of each mudstone sample in the formation at the first depth of the drilled section, and determine the variation trend of the highest cracking peak parameter of kerogen of each mudstone sample in the formation at the first depth of the drilled section; wherein, the number of mudstone samples in the formation at the first depth of the drilled section is at least one; the formation at the first depth of the drilled section is an overpressure formation;

[0010] a formation overpressure category determination module, configured to determine the formation overpressure category in the formation at the first depth of the drilled section according to the variation trend of the organic carbon content and the variation trend of the highest cracking peak parameter of kerogen.

[0011] Third aspect, an embodiment of the present invention further provides an electronic device, which includes:

[0012] one or more processors;

[0013] a storage device, configured to store one or more programs,

[0014] when the one or more programs are executed by the one or more processors, the one or more processors implement the method for determining the formation overpressure category during drilling according to any one of the embodiments of the present invention.

[0015] Fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, it implements the method for determining the formation overpressure category during drilling according to any one of the embodiments of the present invention.

[0016] The technical solution provided by the embodiment of the present invention determines the variation trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section during drilling according to the rock pyrolysis logging data of each mudstone sample in the formation at the first depth of the drilled section, and determines the variation trend of the highest cracking peak parameter of kerogen of each mudstone sample in the formation at the first depth of the drilled section; wherein, the number of mudstone samples in the formation at the first depth of the drilled section is at least one; the formation at the first depth of the drilled section is an overpressure formation; and determines the formation overpressure category in the formation at the first depth of the drilled section according to the variation trend of the organic carbon content and the variation trend of the highest cracking peak parameter of kerogen. By executing the technical solution provided by the embodiment of the present invention, it is possible to determine the formation overpressure type in real time during drilling, improve the accuracy of formation pressure monitoring while drilling, promote the oil and gas exploration process, and improve the resource development efficiency. Description of the Drawings

[0017] Figure 1It is a flowchart of a method for determining the formation overpressure category during the drilling process provided by an embodiment of the present invention;

[0018] Figure 2 It is a schematic diagram of an application scenario in the drilling of overpressure oil and gas wells in non-hydrocarbon-generating formation during the drilling process provided by an embodiment of the present invention;

[0019] Figure 3 It is a flowchart of another method for determining the formation overpressure category during the drilling process provided by an embodiment of the present invention;

[0020] Figure 4 It is a flowchart of yet another method for determining the formation overpressure category during the drilling process provided by an embodiment of the present invention;

[0021] Figure 5 It is a schematic diagram of an application scenario in the drilling of overpressure oil and gas wells in hydrocarbon-generating formation during the drilling process provided by an embodiment of the present invention;

[0022] Figure 6 It is a schematic diagram of the structure of a device for determining the formation overpressure category during the drilling process provided by an embodiment of the present invention;

[0023] Figure 7 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. Detailed implementation manners

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of convenience of description, only parts related to the present invention are shown in the accompanying drawings, rather than all the structures.

[0025] Figure 1 It is a flowchart of a method for determining the formation overpressure category during the drilling process provided by an embodiment of the present invention. The method can be executed by a device for determining the formation overpressure category during the drilling process. The device can be implemented in a software and / or hardware manner, and the device can be configured in an electronic device for determining the formation overpressure category during the drilling process. The method is applied to a scenario for effectively identifying hydrocarbon generation overpressure during the drilling process. As Figure 1 shown, the technical solution provided by the embodiment of the present invention specifically includes:

[0026] S110: Determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section during the drilling process according to the rock pyrolysis logging data of each mudstone sample in the first-depth formation of the drilled section, and determine the change trend of the maximum cracking peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section.

[0027] Among them, the number of mudstone samples in the formation at the first depth of the drilled section is at least one; the formation at the first depth of the drilled section is an overpressure formation.

[0028] Among them, as Figure 2 shown, the formation at the first depth of the drilled section can be a formation at a well depth of 1500m - 3000m, or the formation at the first depth of the drilled section can also be a formation at a well depth of 3000m - 4000m. The formation at the first depth of the drilled section can be set according to actual needs. The formation at the first depth of the drilled section should be an overpressure formation. An overpressure formation means a formation where overpressure occurs. During the drilling process, cuttings are continuously generated, and mudstone samples are obtained by collecting from the cuttings. In this solution, at least one (for example, ten) mudstone samples can be determined by sampling the cuttings at fixed intervals from the formation at the first depth of the drilled section. Among them, the fixed distance can be 5m, the fixed distance can be 10m, and the fixed distance can be set according to actual needs. And the organic carbon content of each mudstone sample is determined through the rock pyrolysis logging data of each mudstone sample in the formation at the first depth of the drilled section, and furthermore, the highest pyrolysis peak parameter of kerogen of each mudstone sample is determined through the rock pyrolysis logging data of each mudstone sample in the formation at the first depth of the drilled section, and then the change trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section and the change trend of the highest pyrolysis peak parameter of kerogen of each mudstone sample in the formation at the first depth of the drilled section are determined.

[0029] Among them, in this solution, a rock pyrolysis analyzer can be used to analyze the rock pyrolysis logging data of each mudstone sample in the formation at the first depth of the drilled section in real time, and the gas hydrocarbon content (S 0 ), free hydrocarbon content (S 1 ), kerogen hydrocarbon content (S 2 ), residual organic carbon content (S 4 ) and the highest pyrolysis peak parameter of kerogen (T max ) of each mudstone sample in the formation at the first depth of the drilled section are obtained. Then, the formula TOC = 0.083×(S 0 + S 1 + S 2 ) + (S 4 / 10) is used to calculate the organic carbon content (TOC) of each mudstone sample in the formation at the first depth of the drilled section. Furthermore, the change trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section and the change trend of the highest pyrolysis peak parameter of kerogen of each mudstone sample in the formation at the first depth of the drilled section are obtained.

[0030] S120: Determine the formation overpressure category in the formation at the first depth of the drilled section according to the change trend of the organic carbon content and the change trend of the highest pyrolysis peak parameter of kerogen.

[0031] Among them, in the formation at the first depth of the drilled section, when the total organic carbon content increases as the well depth increases, and the overall highest pyrolysis peak of kerogen remains unchanged, it indicates that the overpressure in the formation at the first depth of the drilled section encountered is non-hydrocarbon-generation-related overpressure. When the total organic carbon content increases as the well depth increases, and the overall highest pyrolysis peak of kerogen also increases, it indicates that the overpressure in the formation at the first depth of the drilled section encountered is hydrocarbon-generation-related overpressure. Exemplarily, as Figure 2 shown, assuming that the formation at the first depth of the drilled section is in the formation at a well depth of 4400m - 5000m, from Figure 2 it can be seen that in the formation at a well depth of 4400m - 4800m, when the total organic carbon content increases as the well depth increases, and the overall highest pyrolysis peak of kerogen remains unchanged, the overpressure in the formation at a well depth of 4400m - 4800m is non-hydrocarbon-generation-related overpressure. In the formation at a well depth of 4800m - 5000m, when the total organic carbon content increases as the well depth increases, and the overall highest pyrolysis peak of kerogen also increases, the overpressure in the formation at a well depth of 4800m - 5000m is hydrocarbon-generation-related overpressure.

[0032] The technical solution provided by the embodiment of the present invention determines the change trend of the total organic carbon content of each mudstone sample in the formation at the first depth of the drilled section during the drilling process, and determines the change trend of the highest pyrolysis peak parameter of kerogen of each mudstone sample in the formation at the first depth of the drilled section; wherein, the number of mudstone samples in the formation at the first depth of the drilled section is at least one; the formation at the first depth of the drilled section is an overpressure formation; according to the change trend of the total organic carbon content and the change trend of the highest pyrolysis peak parameter of kerogen, the formation overpressure category in the formation at the first depth of the drilled section is determined. By implementing the technical solution provided by the embodiment of the present invention, it is possible to determine the formation overpressure type in real time during the drilling process, improve the accuracy of formation pressure monitoring while drilling, promote the oil and gas exploration process, and improve the resource development efficiency.

[0033] Figure 3 is a flowchart of the method for determining the formation overpressure category during the drilling process provided by the embodiment of the present invention, and this embodiment is optimized on the basis of the above embodiment. As Figure 3 shown, the method for determining the formation overpressure category during the drilling process in the embodiment of the present invention may include:

[0034] S210: Determine the drillability parameters of each mudstone sample in the formation at the second depth of the drilled section during the drilling process.

[0035] Among them, the maximum formation depth value in the formation at the second depth of the drilled section is less than or equal to the minimum formation depth value in the formation at the first depth of the drilled section.

[0036] Exemplarily, assume that the formation at the first depth in the drilled section is a formation located at a well depth of 4400m - 5000m. Then, the maximum formation depth value in the formation at the second depth in the drilled section must be less than or equal to 4400m. In this solution, the rock drillability parameter (dc) of the entire well can be extracted from the data monitored in real time by the comprehensive logging instrument, for example, the sampling interval is 1m / point; then, according to the cuttings logging profile, mudstone layers with a thickness greater than 3m in the formation at the second depth in the drilled section are extracted, and the rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section are obtained.

[0037] S220: Preprocess the rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section to determine the change trend line of the rock drillability parameter with the well depth.

[0038] Among them, in this solution, the rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section can be fitted with a power function to obtain the change trend line of the rock drillability parameter of the entire well with the well depth.

[0039] In a feasible implementation, optionally, preprocessing the rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section to determine the change trend line of the rock drillability parameter with the well depth includes: performing linear regression on the actual rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section and the depth where each mudstone sample is located in a semi-logarithmic coordinate system to determine the change trend line of the rock drillability parameter with the well depth.

[0040] Among them, since the uniform change of the rock drillability parameter with the well depth shows a power-law exponential change trend, this solution can perform linear regression on the rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section and the well depth in a semi-logarithmic coordinate system to obtain the change trend line of the rock drillability parameter of the entire well with the well depth, and this change trend line is a straight line.

[0041] Thus, by performing linear regression on the actual rock drillability parameters of each mudstone sample in the formation at the second depth in the drilled section and the depth where each mudstone sample is located in a semi-logarithmic coordinate system to determine the change trend line of the rock drillability parameter with the well depth, a linear correspondence relationship between the rock drillability parameter of the entire well and the well depth can be established, providing an accurate reference basis for the subsequent steps.

[0042] S230: Determine the formation pressure state of the formation at the first depth in the drilled section according to the change trend line and the actual rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section.

[0043] Among them, the formation pressure state can be a normal pressure formation, or it can be an overpressure formation, and the formation pressure state can be set according to actual needs. In this solution, real-time monitoring data can be generated by comprehensively logging the cuttings logging profiles of each mudstone sample in the formation at the first depth of the drilled section through a comprehensive logging tool, and the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section can be extracted from the real-time monitoring data. Then, the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section with the well depth can be obtained. And according to the variation trend line of the rock drillability parameters with the well depth, the variation trend of the predicted rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section with the well depth can be determined. Based on the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section with the well depth and the variation trend of the predicted rock drillability parameters with the well depth, the formation pressure state of the formation at the first depth of the drilled section can be determined.

[0044] In another feasible implementation manner, optionally, determining the formation pressure state of the formation at the first depth of the drilled section according to the variation trend line and the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section includes: determining the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section with the well depth according to the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section; determining the formation pressure state of the formation at the first depth of the drilled section according to the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section with the well depth and the variation trend of the predicted rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section with the well depth.

[0045] Exemplarily, as Figure 2 shown, assuming that the formation at the first depth of the drilled section is the formation located at a well depth of 4400 m - 5000 m, by Figure 2It can be seen that this solution can determine the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth according to the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section. And according to the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth and the variation trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section, the formation pressure state of the first-depth formation of the drilled section is determined. For example, if the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is consistent with the variation trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section, it is determined that the formation pressure state of the first-depth formation of the drilled section is an atmospheric-pressure formation. If the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section are less than the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section, it is determined that the formation pressure state of the first-depth formation of the drilled section is an overpressure formation.

[0046] Thus, by determining the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section according to the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section; and determining the formation pressure state of the first-depth formation of the drilled section according to the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth and the variation trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section. It is possible to quickly and efficiently directly determine the overpressure formation through real-time logging data, thereby providing a reliable data basis for determining the overpressure cause category of the overpressure formation.

[0047] In this embodiment, optionally, determining the formation pressure state of the first-depth formation of the drilled section according to the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth and the variation trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section includes: if it is determined that the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is inconsistent with the variation trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section, it is determined that the formation pressure state of the first-depth formation of the drilled section is an overpressure formation; or, if it is determined that the variation trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is consistent with the variation trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section, it is determined that the formation pressure state of the first-depth formation of the drilled section is an atmospheric-pressure formation.

[0048] Exemplarily, such as Figure 2As shown, it is assumed that the formation at the first depth in the drilled section is the formation located at a well depth of 4400m - 5000m, and by Figure 2 It can be seen that in the formation at the first depth in the drilled section, the actual rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section are smaller than the predicted rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section. That is, the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section with the well depth is inconsistent with the variation trend of the predicted rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section with the well depth. Then, it is determined that the formation at the first depth in the drilled section is an overpressure formation.

[0049] Exemplarily, as Figure 2 shown, it is assumed that the first-depth formation is the formation located at a well depth of 4100m - 4400m, and by Figure 2 It can be seen that in the formation at the first depth in the drilled section, the actual rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section are basically the same as the predicted rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section. That is, the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section with the well depth is consistent with the variation trend of the predicted rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section with the well depth. Then, it is determined that the formation at the first depth in the drilled section is an underpressure formation.

[0050] Thus, by the variation trend of the actual rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section with the well depth and the variation trend of the predicted rock drillability parameters of each mudstone sample in the formation at the first depth in the drilled section with the well depth, the formation pressure state of the formation at the first depth in the drilled section is determined, and it is possible to quickly and efficiently directly determine the overpressure formation through real-time logging data, thereby providing a reliable data basis for determining the overpressure type of the overpressure formation.

[0051] S240: Determine the variation trend of the organic carbon content of each mudstone sample in the formation at the first depth in the drilled section according to the rock pyrolysis logging data of each mudstone sample in the formation at the first depth in the drilled section during the drilling process, and determine the variation trend of the maximum cracking peak parameter of kerogen of each mudstone sample in the formation at the first depth in the drilled section.

[0052] S250: Determine the formation overpressure category in the formation at the first depth in the drilled section according to the variation trend of the organic carbon content and the variation trend of the maximum cracking peak parameter of kerogen.

[0053] In yet another feasible embodiment, optionally, according to the variation trend of the organic carbon content and the variation trend of the maximum pyrolysis peak parameter of kerogen, determining the formation overpressure category in the formation at the first depth of the drilled well section includes: If it is determined that in the formation at the first depth of the drilled well section, the organic carbon content of each mudstone sample shows an increasing trend with the increase in depth, and the maximum pyrolysis peak parameter of kerogen in each mudstone sample remains unchanged with the increase in depth, then it is determined that the formation overpressure in the formation at the first depth of the drilled well section is non-hydrocarbon-generation overpressure; or, if it is determined that in the formation at the first depth of the drilled well section, the organic carbon content of each mudstone sample shows an increasing trend with the increase in depth, and the maximum pyrolysis peak parameter of kerogen in each mudstone sample also shows an increasing trend with the increase in depth, then it is determined that the formation overpressure in the formation at the first depth of the drilled well section is hydrocarbon-generation overpressure.

[0054] Exemplarily, assume that the formation at the first depth of the drilled well section is in the formation at a well depth of 4400m - 4800m, and it consists of Figure 2 It can be seen that when the organic carbon content increases as a whole with the increase in well depth, and the maximum pyrolysis peak of kerogen remains unchanged as a whole, the overpressure in the formation at the first depth of the drilled well section with a well depth of 4400m - 4800m is non-hydrocarbon-generation overpressure, that is, non-hydrocarbon-generation overpressure. Assume that the formation at the first depth of the drilled well section is in the formation at a well depth of 4800m - 5000m. When the organic carbon content increases as a whole with the increase in well depth, and the maximum pyrolysis peak of kerogen also increases as a whole, the overpressure in the formation at the first depth of the drilled well section with a well depth of 4800m - 5000m is hydrocarbon-generation overpressure, that is, hydrocarbon-generation overpressure.

[0055] Thus, by determining the formation overpressure type of the overpressure formation through the variation trend of the organic carbon content of each mudstone sample with the well depth and the variation trend of the maximum pyrolysis peak parameter of kerogen in each mudstone sample with the well depth in the formation at the first depth of the drilled well section, it is possible to quickly and efficiently directly determine the formation overpressure type through real-time logging data, and the timeliness of monitoring the formation pressure during the logging process can be ensured.

[0056] The technical solution provided by the embodiment of the present invention determines the rock drillability parameters of each mudstone sample in the formation at the second depth of the drilled section during the drilling process; preprocesses the rock drillability parameters of each mudstone sample in the formation at the second depth of the drilled section to determine the change trend line of the rock drillability parameters with the well depth; determines the formation pressure state of the formation at the first depth of the drilled section according to the change trend line and the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section; determines the change trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section according to the rock pyrolysis logging data of each mudstone sample in the formation at the first depth of the drilled section during the drilling process, and determines the change trend of the maximum cracking peak parameter of kerogen of each mudstone sample in the formation at the first depth of the drilled section; determines the formation overpressure category in the formation at the first depth of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameter of kerogen. By implementing this solution, it is possible to determine the formation pressure state and the formation overpressure type in real time during the drilling process, improve the accuracy of formation pressure monitoring while drilling, promote the oil and gas exploration process, and improve the resource development efficiency.

[0057] The main methods for determining the formation overpressure category in the related art can be summarized as the following several types:

[0058] 1. Acoustic - density - effective stress chart method. This method was proposed and continuously improved by Bowers G L. It is necessary to collect acoustic logging, density logging and formation pressure data of a single well. First, calculate the formation vertical effective stress by combining the regional overlying formation pressure model, then cross - plot the compressional wave velocity, density and vertical effective stress at the same depth in pairs, and then identify the overpressure cause corresponding to the theoretical discrimination chart. This method has a lot of theoretical basis and application examples, and is highly recognized in the industry. However, its disadvantage is that its application premise is that the formation pressure data is known, and it cannot be applied in the formation pressure monitoring while drilling.

[0059] 2. Eaton index back - calculation method. The theoretical basis of this method is the Eaton method, that is, the model constants (Eaton index, dimensionless parameter) of different - origin overpressures are different when calculating the formation pressure using the Eaton method. For example, the Eaton index corresponding to overpressure caused by undercompaction is usually 1.2, while the Eaton index corresponding to overpressure caused by hydrocarbon generation, fluid conduction, etc. is 1.8, 2.0 or even larger. Therefore, under the condition of known formation pressure data, the Eaton index applicable to a certain depth formation can be back - calculated according to the Eaton method model, and the overpressure cause can be discriminated using the Eaton index. This method is similar to the first method. In essence, it is a post - hoc back - calculation method and cannot be applied in the formation pressure monitoring while drilling.

[0060] 3. Porosity contrast method. The porosity contrast method is to compare the porosity of the overpressure section with the porosity under normal pressure at the same depth to determine whether there is porosity anomaly in the overpressure section and its cause. Since formation overpressure caused by undercompaction generally has the characteristic of abnormally high porosity, the overpressure caused by unbalanced compaction can be determined by porosity contrast. In specific applications, density logging data is generally used to characterize the volume properties of rocks, and the inflection points of the density logging curve and other response parameters (such as acoustic logging, resistivity logging, and modified drill pressure index) are compared (a regression trend line is made in the normal pressure section of the curve, and the deviation from the trend line is regarded as the appearance of an inflection point). If the inflection points of the density curve and other curves appear synchronously, it is caused by undercompaction. If the inflection point depth of the density curve lags, it is caused by hydrocarbon generation, fluid conduction, etc. Compared with the previous two methods, this method can be implemented during the drilling process, but it is limited by the harsh environment of abnormally high pressure formations (usually with high temperature, and current downhole acoustic logging and other measurement instruments cannot work properly) and economic benefits (the daily cost of downhole acoustic logging and other measurement instruments is extremely high). Currently, oil and gas wells using downhole acoustic and density logging during drilling are extremely rare, and these two parameters are usually obtained during the post-drilling completion logging. Therefore, this method is generally applied to post-drilling evaluation, and its application range during the drilling process is limited.

[0061] In view of the current technical situation that there are many hydrocarbon generation overpressures encountered during drilling but they cannot be effectively identified, this solution provides a method that can accurately identify hydrocarbon generation overpressure using drilling data, thereby improving the accuracy of formation pressure monitoring during drilling.

[0062] Figure 4 The following is a flow chart of the method for determining the type of formation overpressure during drilling provided by the embodiments of the present invention. To more clearly describe the technical solution of the present invention, the technical solution provided by the embodiments of the present invention may include the following steps:

[0063] Step 1: Determine the drillability parameters of each mudstone sample in the formation at the second depth of the drilled section during the drilling process.

[0064] This solution can extract the drillability parameters (dc) of the whole well from the data monitored by the comprehensive logging tool in real time, with a sampling interval of 1 m / point; then, according to the cuttings logging profile, mudstone layers with a thickness greater than 3 m in the formation at the second depth of the drilled section are extracted to obtain the drillability parameters of each mudstone sample in the formation at the second depth of the drilled section.

[0065] Step 2: Preprocess the drillability parameters of each mudstone sample in the formation at the second depth of the drilled section to determine the change trend line of the drillability parameters with well depth.

[0066] This solution can analyze the rock drillability parameter data of each mudstone sample in the second-depth formation of the drilled section obtained in Step 1, perform a linear regression of the rock drillability parameters and depth in a semi-logarithmic coordinate system, and obtain the normal compaction trend line of the rock drillability parameters, that is, the trend line of the change of the rock drillability parameters with the well depth.

[0067] Step 3: Determine the formation pressure state of the first-depth formation of the drilled section according to the change trend line and the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section.

[0068] This solution can analyze the relative change relationship between the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section and the normal compaction trend line: in the normal pressure formation, the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section generally increase with the increase of depth along the normal compaction trend line. When the actual rock drillability parameter of the mudstone in the newly drilled section is smaller than the predicted value of the trend line, it is considered that the formation overpressure is encountered.

[0069] Step 4: Determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section according to the rock pyrolysis logging data of each mudstone sample in the first-depth formation of the drilled section during the drilling process, and determine the change trend of the maximum cracking peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section.

[0070] This solution can obtain the rock pyrolysis logging parameters of each mudstone sample in the first-depth formation of the drilled section through a rock pyrolysis analyzer, including the gaseous hydrocarbon content (S 0 ), the free hydrocarbon content (S 1 ), the kerogen hydrocarbon content (S 2 ), the residual organic carbon content (S 4 ), and the maximum cracking peak parameter of the kerogen (T max ). The sampling interval depends on the specific logging construction requirements. And from the data processed in real time by the rock pyrolysis analyzer, extract the gaseous hydrocarbon content (S 0 ), the free hydrocarbon content (S 1 ), and the kerogen hydrocarbon content (S 2 ) parameters of the mudstone sample, and then use the following formula to calculate the organic carbon content (TOC) of the mudstone sample: TOC = 0.083×(S 0 + S 1 + S 2 ) + (S 4 / 10).

[0071] Among them, TOC represents the total organic carbon content, expressed in %; S 0 represents the hydrocarbon content in the unit mass of mudstone detected at 90°C, with the unit of mg / g; S 1It represents the hydrocarbon content in per unit mass of mudstone detected at 300°C, with the unit of mg / g; S 2 It represents the hydrocarbon content in per unit mass of mudstone detected at 300°C to 600°C, with the unit of mg / g; S 4 It represents the residual organic carbon content in per unit mass of mudstone after pyrolysis, with the unit of mg / g.

[0072] Step 5: Determine the formation overpressure category in the first-depth formation of the drilled well section according to the change trend of the organic carbon content and the change trend of the maximum pyrolysis peak parameter of kerogen.

[0073] This solution can determine the formation overpressure category in the first-depth formation of the drilled well section by analyzing the relative change relationship between the organic carbon content of the mudstone sample and the maximum pyrolysis peak parameter of kerogen: when the organic carbon content increases as a whole with the increase of well depth and the maximum pyrolysis peak of kerogen remains unchanged as a whole, the formation overpressure encountered is non-hydrocarbon-generation origin overpressure; when the organic carbon content increases as a whole with the increase of well depth and the maximum pyrolysis peak of kerogen also increases as a whole, the formation overpressure encountered is hydrocarbon-generation origin overpressure. It improves the accuracy of formation pressure monitoring while drilling from the overpressure formation mechanism.

[0074] As Figure 4 shown, the technical solution provided by the embodiment of the present invention, through real-time processing of rock pyrolysis logging data, calculates the organic carbon content (TOC) and collects the maximum pyrolysis peak parameter of kerogen (T max ); through the comprehensive logging instrument, real-time data collection is carried out to obtain the drillability parameter (dc) of the rock, and the change trend of the dc index is analyzed. If the dc index increases along the normal trend line with the increase of depth, the drilled well section is normal pressure. If the dc index is negatively deviated relative to the normal trend line after entering a certain section, abnormal pressure is encountered. When abnormal pressure is encountered, further analyze the change trend of TOC and T max curves in the abnormal pressure section. If TOC increases with the increase of depth and the T max curve remains unchanged with the increase of depth, it indicates that the hydrocarbon generation of mudstone is inhibited, and the encountered abnormal pressure belongs to non-hydrocarbon-generation overpressure, and its origin type is fluid conduction; if TOC increases with the increase of depth and the T max curve increases with the increase of depth, it indicates that the hydrocarbon generation of mudstone is not inhibited, and the encountered abnormal pressure is hydrocarbon-generation overpressure.

[0075] Figure 2 shows the application scenario schematic diagram of this solution in the oil and gas drilling with non-hydrocarbon-generation origin formation overpressure: The A formation encountered in Well X is developed with overpressure. During drilling, first collect the rock pyrolysis logging data to obtain the organic carbon content (TOC) of this well and collect the maximum pyrolysis peak parameter of kerogen (T max) data, and then judge that the abnormal pressure section is entered in Group A by monitoring the drillability data of the mudstone points. Further analyze the total organic carbon content (TOC) and the parameter of the highest cracking peak of kerogen (T max ) curve: while the depth increases, the total organic carbon content (TOC) increases, and the parameter of the highest cracking peak of kerogen (T max ) no longer increases after entering Group A, judge that hydrocarbon generation is inhibited, so the overpressure encountered in this well section is non-hydrocarbon-generation overpressure. Combining with the common overpressure formation types in this area, it is considered to be caused by fluid conduction.

[0076] Figure 5 The schematic diagram of the application scenario of the present solution in the drilling of overpressure oil and gas wells in hydrocarbon-generation formation is shown: The overpressure develops in the B group and C group formations encountered by Well Y. During the drilling, first collect the rock pyrolysis logging data to obtain the total organic carbon content (TOC) of this well and collect the parameter of the highest cracking peak of kerogen (T max ) data, and then judge that the abnormal pressure section is entered in the C group well section by monitoring the drillability data of the mudstone points. Further analyze the total organic carbon content (TOC) and the parameter of the highest cracking peak of kerogen (T max ) curve: while the depth increases, the total organic carbon content (TOC) increases, and the parameter of the highest cracking peak of kerogen (T max ) also increases uniformly with the increase of depth, judge that hydrocarbon generation is not inhibited. Combining with the common overpressure formation types in this area, it is considered that the overpressure encountered in this well section is hydrocarbon-generation overpressure.

[0077] The present invention has been applied in the monitoring of formation pressure while drilling in more than 10 wells in a certain basin. The coincidence rate of the judgment of hydrocarbon-generation formation overpressure while drilling reaches 95%. It is basically consistent with the analysis results of the commonly used methods such as the chart method, the back-calculation method, and the porosity comparison method, and real-time analysis while drilling is achieved, with the convenience of operation and good application effect.

[0078] The application in this basin shows that the method of identifying hydrocarbon-generation formation overpressure by using the variation characteristics of geochemical logging parameters of rocks while drilling has a good discrimination coincidence rate under different well depths and different formation conditions. This method is not affected by factors such as the geological condition background and the change of drilling engineering conditions. It can identify hydrocarbon-generation formation overpressure in a timely and accurate manner in both the development blocks with a higher well control degree and the new area exploration with a lower well control degree. Its application results effectively improve the accuracy and reliability of formation pressure monitoring while drilling in the area, and successfully guarantee the safety of oil and gas drilling engineering.

[0079] The technical solution provided by the embodiment of the present invention is based on the real-time logging data at the drilling site, and timely determines the occurrence of hydrocarbon generation overpressure on the basis of overpressure identification, providing a reliable basis for the accurate monitoring of formation overpressure. Furthermore, it improves the real-time performance and accuracy of the existing formation pressure monitoring method while drilling, providing a basis for the adjustment of drilling fluid density and on-site operation decision-making.

[0080] Figure 6 It is a schematic structural diagram of a device for determining the type of formation overpressure during drilling, and the device can be configured in an electronic device for determining the type of formation overpressure during drilling, such as Figure 6 shown, the device includes:

[0081] The change trend determination module 310 is used to determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section during drilling according to the rock pyrolysis logging data of each mudstone sample in the first-depth formation of the drilled section, and to determine the change trend of the highest cracking peak parameter of kerogen of each mudstone sample in the first-depth formation of the drilled section; wherein, the number of mudstone samples in the first-depth formation of the drilled section is at least one; the first-depth formation is an overpressure formation;

[0082] The formation overpressure type determination module 320 is used to determine the formation overpressure type in the first-depth formation of the drilled section according to the change trend of the organic carbon content and the change trend of the highest cracking peak parameter of kerogen.

[0083] Optionally, the formation overpressure type determination module 320 includes a non-hydrocarbon generation overpressure determination unit, which is used to determine that the formation overpressure in the first-depth formation of the drilled section is non-hydrocarbon generation overpressure if it is determined that the organic carbon content of each mudstone sample in the first-depth formation of the drilled section shows an increasing trend with the increase of depth, and the highest cracking peak parameter of kerogen of each mudstone sample shows an unchanged trend with the increase of depth; or, a hydrocarbon generation overpressure determination unit, which is used to determine that the formation overpressure in the first-depth formation of the drilled section is hydrocarbon generation overpressure if it is determined that the organic carbon content of each mudstone sample in the first-depth formation of the drilled section shows an increasing trend with the increase of depth, and the highest cracking peak parameter of kerogen of each mudstone sample also shows an increasing trend with the increase of depth.

[0084] Optionally, the device further includes a rock drillability parameter determination unit, configured to determine the rock drillability parameters of each mudstone sample in the second-depth formation of the drilled section during the drilling process before determining the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section based on the rock pyrolysis logging data of each mudstone sample in the first-depth formation of the drilled section during the drilling process, and determining the change trend of the maximum pyrolysis peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section; wherein, the maximum formation depth value in the second-depth formation of the drilled section is less than or equal to the minimum formation depth value in the first-depth formation of the drilled section; a first change trend line determination unit, configured to preprocess the rock drillability parameters of each mudstone sample in the second-depth formation of the drilled section, and determine the change trend line of the rock drillability parameters with the well depth; a formation pressure state determination unit, configured to determine the formation pressure state of the first-depth formation according to the change trend line and the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section.

[0085] Optionally, the first change trend line determination unit is specifically configured to perform linear regression on the actual rock drillability parameters of each mudstone sample in the second-depth formation of the drilled section and the depths of each mudstone sample in a semi-logarithmic coordinate system, and determine the change trend line of the rock drillability parameters with the well depth.

[0086] Optionally, the formation pressure state determination unit includes a second change trend determination subunit, configured to determine the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth according to the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section; a formation pressure state determination subunit, configured to determine the formation pressure state of the first-depth formation of the drilled section according to the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth and the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth.

[0087] Optionally, the formation pressure state determination subunit is specifically configured to, if it is determined that the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is inconsistent with the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth, determine that the formation pressure state of the first-depth formation of the drilled section is an overpressure formation; or, if it is determined that the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is consistent with the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth, determine that the formation pressure state of the first-depth formation of the drilled section is an atmospheric pressure formation.

[0088] The device provided in the above embodiments can execute the method for determining the formation overpressure category during drilling provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects for executing the method.

[0089] Figure 7 It is a schematic structural diagram of an electronic device provided in an embodiment of the present invention. As Figure 7 shown, the device includes:

[0090] One or more processors 410, Figure 7 Taking one processor 410 as an example;

[0091] A memory 420;

[0092] The device may further include: an input device 430 and an output device 440.

[0093] The processor 410, the memory 420, the input device 430, and the output device 440 in the device may be connected through a bus or other means, Figure 7 Taking connection through a bus as an example.

[0094] The memory 420, as a non-transitory computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as program instructions / modules corresponding to a method for determining the formation overpressure category during drilling in an embodiment of the present invention. The processor 410 executes various functional applications and data processing of the computer device by running the software programs, instructions, and modules stored in the memory 420, that is, to implement a method for determining the formation overpressure category during drilling in the above method embodiment, that is:

[0095] Determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section during drilling, and determine the change trend of the maximum cracking peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section; wherein, the number of mudstone samples in the first-depth formation of the drilled section is at least one; the first-depth formation of the drilled section is an overpressure formation;

[0096] Determine the formation overpressure category in the first-depth formation of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameter of the kerogen.

[0097] The memory 420 may include a program storage area and a data storage area. The program storage area may store an operating system and application programs required for at least one function. The data storage area may store data created according to the use of the computer device and the like. In addition, the memory 420 may include high-speed random access memory and may also include non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory 420 may optionally include a memory remotely provided with respect to the processor 410, and these remote memories may be connected to the terminal device through a network. Examples of the above networks include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0098] The input device 430 may be used to receive input digital or character information and generate key signal inputs related to the user settings and function controls of the computer device. The output device 440 may include display devices such as a display screen.

[0099] Embodiments of the present invention provide a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements a method for determining the formation overpressure category during the drilling process provided by the embodiments of the present invention, that is:

[0100] Determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section during the drilling process, and determine the change trend of the maximum pyrolysis peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section; wherein, the number of mudstone samples in the first-depth formation of the drilled section is at least one; the first-depth formation of the drilled section is an overpressure formation;

[0101] Determine the formation overpressure category in the first-depth formation of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum pyrolysis peak parameter of the kerogen.

[0102] Any combination of one or more computer-readable media may be employed. The computer-readable media may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

[0103] A computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, in which the computer-readable program code is carried. Such a propagated data signal may take many forms, including—but not limited to—electromagnetic signals, optical signals, or any suitable combination of the foregoing. The computer-readable signal medium may also be any computer-readable medium that is not a computer-readable storage medium and that can send, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

[0104] The program code embodied on the computer-readable medium may be transmitted using any appropriate medium, including—but not limited to—wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0105] The computer program code for carrying out operations of the present invention may be written in one or more programming languages, or combinations thereof, including object-oriented programming languages such as Java, Smalltalk, C++, and also including conventional procedural programming languages such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer, or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., through the Internet using an Internet service provider).

[0106] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for determining the formation overpressure category during drilling, characterized in that, it includes: Determining the change trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section during drilling, and determining the change trend of the maximum cracking peak parameters of the kerogen of each mudstone sample in the formation at the first depth of the drilled section; wherein, the number of mudstone samples in the formation at the first depth of the drilled section is at least one; the formation at the first depth of the drilled section is an overpressure formation; Determining the formation overpressure category in the formation at the first depth of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameters of the kerogen; Among them, determining the formation overpressure category in the formation at the first depth of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameters of the kerogen includes: If it is determined that in the formation at the first depth of the drilled section, the organic carbon content of each mudstone sample shows an increasing trend with the increase of depth, and the maximum cracking peak parameters of the kerogen of each mudstone sample remain unchanged with the increase of depth, then it is determined that the formation overpressure in the formation at the first depth of the drilled section is non-hydrocarbon-generating overpressure; or, If it is determined that in the formation at the first depth of the drilled section, the organic carbon content of each mudstone sample shows an increasing trend with the increase of depth, and the maximum cracking peak parameters of the kerogen of each mudstone sample also show an increasing trend with the increase of depth, then it is determined that the formation overpressure in the formation at the first depth of the drilled section is hydrocarbon-generating overpressure.

2. The method according to claim 1, characterized in that, Before determining the change trend of the organic carbon content of each mudstone sample in the formation at the first depth of the drilled section during drilling and determining the change trend of the maximum cracking peak parameters of the kerogen of each mudstone sample in the formation at the first depth of the drilled section, it further includes: Determining the rock drillability parameters of each mudstone sample in the formation at the second depth of the drilled section during drilling; wherein, the maximum formation depth value in the formation at the second depth of the drilled section is less than or equal to the minimum formation depth value in the formation at the first depth of the drilled section; Preprocessing the rock drillability parameters of each mudstone sample in the formation at the second depth of the drilled section to determine the change trend line of the rock drillability parameters with the well depth; Determining the formation pressure state of the formation at the first depth of the drilled section according to the change trend line and the actual rock drillability parameters of each mudstone sample in the formation at the first depth of the drilled section.

3. The method according to claim 2, characterized in that, Preprocessing the rock drillability parameters of each mudstone sample in the formation at the second depth of the drilled section to determine the change trend line of the rock drillability parameters with the well depth, including: Performing linear regression on the actual rock drillability parameters of each mudstone sample in the formation at the second depth of the drilled section and the depth where each mudstone sample is located in a semi-logarithmic coordinate system to determine the change trend line of the rock drillability parameters with the well depth.

4. The method according to claim 2, characterized in that, Determine the formation pressure state of the first-depth formation in the drilled section according to the change trend line and the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section, including: Determine the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth according to the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section; Determine the formation pressure state of the first-depth formation in the drilled section according to the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth and the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth.

5. The method according to claim 4, wherein, Determine the formation pressure state of the first-depth formation in the drilled section according to the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth and the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth, including: If it is determined that the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is inconsistent with the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth, then determine that the formation pressure state of the first-depth formation in the drilled section is an overpressure formation; Or, if it is determined that the change trend of the actual rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth is consistent with the change trend of the predicted rock drillability parameters of each mudstone sample in the first-depth formation of the drilled section with the well depth, then determine that the formation pressure state of the first-depth formation in the drilled section is an atmospheric pressure formation.

6. A device for determining the formation overpressure category during drilling, wherein, comprising: A change trend determination module, configured to determine the change trend of the organic carbon content of each mudstone sample in the first-depth formation of the drilled section according to the rock pyrolysis logging data of each mudstone sample in the first-depth formation of the drilled section during the drilling process, and determine the change trend of the maximum cracking peak parameter of the kerogen of each mudstone sample in the first-depth formation of the drilled section; wherein, the number of mudstone samples in the first-depth formation of the drilled section is at least one; the first-depth formation of the drilled section is an overpressure formation; A formation overpressure category determination module, configured to determine the formation overpressure category in the first-depth formation of the drilled section according to the change trend of the organic carbon content and the change trend of the maximum cracking peak parameter of the kerogen; Among them, the formation overpressure category determination module includes: A non-hydrocarbon-generation overpressure determination unit, configured to determine that the formation overpressure in the first-depth formation of the drilled section is a non-hydrocarbon-generation overpressure if it is determined that in the first-depth formation of the drilled section, the organic carbon content of each mudstone sample shows an increasing trend with the increase of depth, and the maximum cracking peak parameter of the kerogen of each mudstone sample remains unchanged with the increase of depth; or, A hydrocarbon generation overpressure determination unit is configured to determine that the formation overpressure in the formation at the first depth in the drilled well section is a hydrocarbon generation overpressure if it is determined that in the formation at the first depth in the drilled well section, the organic carbon content of each mudstone sample shows an increasing trend with the increase in depth, and the maximum pyrolysis peak parameter of the kerogen in each mudstone sample also shows an increasing trend with the increase in depth.

7. An electronic device, characterized in that, it includes: one or more processors; a storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, enabling the one or more processors to implement the method for determining the formation overpressure category during the drilling process according to any one of claims 1 - 5.

8. A computer-readable storage medium, on which a computer program is stored, characterized in that, when the program is executed by a processor, it implements the method for determining the formation overpressure category during the drilling process according to any one of claims 1 - 5.

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