A shale gas horizontal well reservoir quality-drilling quality real-time evaluation method and system

Abstract

The application discloses a shale gas horizontal well reservoir quality-drilling quality real-time evaluation method and system, and acquires a reservoir quality coefficient through normalized evaluation logging data; the influence of human subjective empowerment is reduced; and acquires mechanical specific energy through collected real-time drilling parameters; effectively evaluates drilling efficiency under normal working conditions; the application acquires a mechanical specific energy curve, a mechanical drilling speed curve and a drilling pressure curve through a horizontal well guide model and mechanical specific energy, and selects a positive area of reservoir quality-drilling quality; realizes reservoir quality-drilling quality evaluation in a real drilling process through positive overlap between mechanical specific energy and the reservoir quality coefficient and positive overlap between drilling pressure and mechanical drilling speed, guarantees shale gas block horizontal well reservoir drilling rate, improves drilling efficiency, and can effectively solve the contradiction between shale gas reservoir drilling rate and drilling efficiency.

Description

Technical Field

[0001] This invention belongs to the field of unconventional oil and gas reservoir drilling and exploration technology, and relates to a method and system for real-time evaluation of shale gas horizontal well reservoir quality and drilling quality. Background Technology

[0002] Given the complexity and unique characteristics of shale gas drilling engineering in China, good reservoir quality is the geological foundation for successful shale gas development. Drilling quality determines the difficulty, technical direction, and overall cost of drilling and completion techniques and engineering implementation, and is a fundamental support for achieving breakthroughs and economic benefits in shale gas development. Currently, shale gas block quality evaluation technologies mainly rely on pre-drilling or post-drilling reservoir and completion quality evaluations based on seismic and well logging data, and a few post-drilling reservoir and completion quality evaluations using experimental methods. Very few technologies and methods address reservoir and drilling quality evaluation during the drilling process. Pre-drilling or post-drilling evaluations often lead to a polarization in shale gas production, long drilling cycles, high drilling costs, and an increasingly prominent contradiction between reservoir encounter rate and drilling efficiency, making it difficult to meet the needs of integrated and efficient exploration and development of shale gas geology and engineering. Summary of the Invention

[0003] The purpose of this invention is to address the problems in existing technologies where pre-drilling or post-drilling evaluations often lead to a polarization in shale gas production, resulting in long drilling cycles, high drilling costs, and very little evaluation of reservoir quality and drilling quality during the drilling process. This invention provides a method and system for real-time evaluation of reservoir quality and drilling quality in shale gas horizontal wells.

[0004] To achieve the above objectives, the present invention employs the following technical solution: A real-time evaluation method for reservoir quality and drilling quality in shale gas horizontal wells includes: Collect logging data from neighboring wells around the well to be drilled, and perform normalized evaluation on the logging data; Reservoir quality coefficients are obtained based on logging data from normalized evaluation. Real-time drilling parameters are collected, and mechanical specific energy is obtained based on the collected real-time drilling parameters; Based on the reservoir quality coefficient, and combined with the logging curves, trajectory data, and stratigraphic information of the pilot well and adjacent vertical wells, a single-well steering model for adjacent wells is constructed. Collect logging-while-drilling data, drilling engineering data, and logging parameters, and construct a horizontal well steering model based on the adjacent well single-well steering model; Based on the horizontal well steering model and mechanical specific energy, mechanical specific energy curves, mechanical drilling rate curves, and drilling pressure curves are obtained. Based on the reservoir quality coefficient, mechanical specific energy curve, mechanical drilling rate curve and drilling pressure curve, the positive region of reservoir quality-drilling quality is selected. Real-time comparison of the directional models of adjacent wells and horizontal well models, updating and iterating the horizontal well model to perform real-time directional tracking of horizontal wells, and combining logging while drilling and drilling engineering parameters to analyze the positive region changes of trajectory reservoir quality-drilling quality in real time.

[0005] A further improvement of the present invention is that: Furthermore, logging data from adjacent wells surrounding the well to be drilled includes logging curves for evaluating reservoir quality: porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT).

[0006] Furthermore, based on the normalized evaluation logging data, the reservoir quality coefficient is obtained, specifically as follows: Normalized porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT) were determined as the indicators N1, N2, ..., N for evaluating reservoir quality. i ; Based on the independence weight coefficient method, the collinearity relationship between any indicator and other indicators is determined; Based on the collinearity relationship between any indicator and other indicators, obtain the multiple correlation coefficient between any indicator and other indicators; Based on the correlation coefficient method and the reciprocal of the multiple correlation coefficient between any index and other indices, the comprehensive coefficient of each index is obtained, and the independence weight of the index items for evaluating reservoir quality is obtained. Based on independence weights, the reservoir quality coefficient of shale formations is obtained.

[0007] Furthermore, based on the collinearity between any indicator and other indicators, the multiple correlation coefficient between any indicator and other indicators is obtained, specifically as follows: If any index N i Other indicators The multiple correlation coefficient is negative; the multiple correlation coefficient is:

[0008] in, ; In the formula: This is the multiple correlation coefficient; For a certain reservoir quality index; This represents the average value of reservoir quality indicators; This is a linear combination of other reservoir quality indicators; , It is a constant; The independence weights of the indicators for evaluating reservoir quality are as follows:

[0009] In the formula: The independent weights for each indicator; The correlation coefficient; Based on independence weights, the reservoir quality coefficient of shale formations is obtained.

[0010] In the formula: Hg is the reservoir quality coefficient; m is the number of reservoir quality indicators; N i These are normalized reservoir quality parameters.

[0011] Furthermore, before obtaining the mechanical specific energy based on the collected real-time drilling parameters, the following steps are also included: Collect drilling engineering parameters, including mechanical parameters, hydraulic parameters, drilling fluid properties, and rheological parameters; Based on rough set theory, the positive domain of rough set is used to determine the relative importance of mechanical parameters, hydraulic parameters, drilling fluid properties and rheological parameters to the evaluation results, and to obtain the importance ranking of attribute evaluation indicators. The mechanical parameters with the highest importance ranking among the attribute evaluation indicators are selected to evaluate drilling efficiency.

[0012] Furthermore, mechanical parameters include drilling pressure and rotational speed; hydraulic parameters include riser pump pressure, displacement, and nozzle combination; drilling fluid properties and rheological parameters include drilling fluid density, viscosity, slice size, fluid loss, mud cake, solids content, and pH.

[0013] Furthermore, based on the collected real-time drilling parameters, the mechanical specific energy is obtained, specifically:

[0014] in, WOB Drilling pressure (kN); RPM (rotation speed, r / min); T (torque, kN·m); ROP The drilling speed is mechanical, in m / h; The value is the drill bit diameter, in cm.

[0015] Furthermore, logging-while-drilling data, drilling engineering data, and logging parameters are collected, and a horizontal well steering model is constructed based on the adjacent well single-well steering model; specifically: Real-time logging-while-drilling data, drilling engineering data, and logging parameters are acquired using WITSML; real-time logging-while-drilling data and adjacent well directional models are imported into the horizontal well directional model using LOGXD directional software.

[0016] Furthermore, based on the horizontal well steering model and mechanical specific energy, the mechanical specific energy curve, mechanical drilling rate curve, and drilling pressure curve are obtained; specifically: The reservoir quality coefficient curve is plotted based on the horizontal well steering model. The mechanical specific energy curve is calculated using real-time drilling parameters through the mechanical specific energy model established by Teale. The mechanical drilling rate curve and drilling pressure curve are then loaded.

[0017] Furthermore, based on the reservoir quality coefficient, mechanical energy curve, mechanical drilling rate curve, and drilling pressure curve, a positive region between reservoir quality and drilling quality is selected; specifically: Place the reservoir quality coefficient and mechanical energy curve in the same curve channel, adjust the left and right scales of the reservoir quality coefficient and mechanical energy curve, select overlapping segments with varying lithology, and set the first positive overlap area and the first negative overlap area. Place the mechanical drilling rate curve and drilling pressure curve into another curve channel, adjust the left and right scales of the mechanical drilling rate and drilling pressure curves, select the overlapping segments where the mechanical drilling rate and drilling pressure are positively correlated, and set the second positive overlap area and the second negative overlap area; the selection of the positive area of ​​reservoir quality-drilling quality is: selecting the first positive overlap area and the second positive overlap area.

[0018] A real-time evaluation system for reservoir quality and drilling quality in shale gas horizontal wells includes: The acquisition module is used to acquire logging data from neighboring wells around the well to be drilled and to perform normalized evaluation on the logging data. A reservoir quality coefficient acquisition module, which acquires the reservoir quality coefficient based on normalized evaluation logging data; A mechanical energy specificity acquisition module, which collects real-time drilling parameters and acquires mechanical energy specificity based on the collected real-time drilling parameters; The adjacent well single-well steering model construction module constructs an adjacent well single-well steering model based on the reservoir quality coefficient and combined with the logging curves, trajectory data, and stratigraphic information of the pilot well and the adjacent vertical well. A horizontal well steering model construction module is provided, which collects logging-while-drilling data, drilling-while-drilling engineering data and logging parameters, and constructs a horizontal well steering model based on the steering model of an adjacent single well. The curve acquisition module acquires the mechanical specific energy curve, mechanical drilling rate curve, and drilling pressure curve based on the horizontal well steering model and mechanical specific energy. The selection module selects the positive region of reservoir quality versus drilling quality based on reservoir quality coefficient, mechanical energy curve, mechanical drilling rate curve and drilling pressure curve. The iterative module compares the directional model of adjacent wells and the horizontal well model in real time, updates and iterates the horizontal well model to perform real-time directional tracking of the horizontal well, and analyzes the positive region changes of the trajectory reservoir quality-drilling quality in real time by combining logging while drilling and drilling engineering parameters.

[0019] Compared with the prior art, the present invention has the following beneficial effects: This invention obtains reservoir quality coefficients through normalized evaluation logging data, reducing the influence of subjective human weighting. It also obtains mechanical specific energy through real-time drilling parameters, effectively evaluating drilling efficiency under normal operating conditions. Furthermore, this invention uses a horizontal well steering model and mechanical specific energy to obtain mechanical specific energy curves, mechanical drilling rate curves, and drilling pressure curves, selecting a positive region between reservoir quality and drilling quality. By employing positive overlap between mechanical specific energy and reservoir quality coefficients, and positive overlap between drilling pressure and mechanical drilling rate, it achieves reservoir quality-drilling quality assessment during actual drilling, ensuring the reservoir encounter rate in shale gas blocks, improving drilling efficiency, and effectively resolving the contradiction between shale gas reservoir encounter rate and drilling efficiency. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A flowchart of the real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to the present invention; Figure 2 This is a structural diagram of the real-time evaluation system for shale gas horizontal well reservoir quality and drilling quality according to the present invention. Figure 3 Another flowchart of the real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to the present invention; Figure 4 A schematic diagram illustrating the curve overlap method for identifying reservoir quality and well quality. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0028] The present invention will now be described in further detail with reference to the accompanying drawings: See Figure 1 This invention discloses a real-time evaluation method for reservoir quality and drilling quality in shale gas horizontal wells, comprising: S101: Collect logging data from neighboring wells around the well to be drilled, and perform normalized evaluation on the logging data.

[0029] Logging data from neighboring wells surrounding the well to be drilled includes logging curves for evaluating reservoir quality: porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT).

[0030] S102, based on normalized evaluation logging data, to obtain reservoir quality coefficient; S102.1, normalized porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT) are determined as the indicators N1, N2, ..., N for evaluating reservoir quality. i ; S102.2, Based on the independence weight coefficient method, determine the collinearity relationship between any indicator and other indicators; S102.3, Based on the collinearity relationship between any indicator and other indicators, obtain the multiple correlation coefficient between any indicator and other indicators; If any index N i Other indicators The multiple correlation coefficient is negative; the multiple correlation coefficient is:

[0031] ; In the formula: This is the multiple correlation coefficient; For a certain reservoir quality index; This represents the average value of reservoir quality indicators; This is a linear combination of other reservoir quality indicators; , It is a constant; S102.4, based on the correlation coefficient method and the reciprocal of the multiple correlation coefficient between any index and other indices, the comprehensive coefficient of each index is obtained, and the independence weight of the index items for evaluating reservoir quality is obtained.

[0032] The independence weights of the indicators for evaluating reservoir quality are as follows:

[0033] In the formula: The independent weights for each indicator; The correlation coefficient; S102.5, based on independence weights, obtains the reservoir quality coefficient of shale formations.

[0034] The reservoir quality coefficient of shale formations is obtained based on independence weights.

[0035] In the formula: Hg is the reservoir quality coefficient; m is the number of reservoir quality indicators; N i These are normalized reservoir quality parameters.

[0036] S103, collects real-time drilling parameters and obtains mechanical specific energy based on the collected real-time drilling parameters; Before obtaining the mechanical specific energy based on the collected real-time drilling parameters, the following steps are also included: collecting mechanical parameters, hydraulic parameters, drilling fluid properties, and rheological parameters from the drilling engineering parameters; Based on rough set theory, the positive domain of rough set is used to determine the relative importance of mechanical parameters, hydraulic parameters, drilling fluid properties and rheological parameters to the evaluation results, and to obtain the importance ranking of attribute evaluation indicators. The mechanical parameters with the highest importance ranking among the attribute evaluation indicators are selected to evaluate drilling efficiency.

[0037] Mechanical parameters include drilling pressure and rotational speed; hydraulic parameters include riser pump pressure, displacement, and nozzle combination; drilling fluid properties and rheological parameters include drilling fluid density, viscosity, slices, fluid loss, mud cake, solids content, and pH.

[0038] Based on the collected real-time drilling parameters, the mechanical specific energy is obtained, specifically...

[0039] in, WOB Drilling pressure (kN); RPM (rotation speed, r / min); T (torque, kN·m); ROP The drilling speed is mechanical, in m / h; The value is the drill bit diameter, in cm.

[0040] S104, based on the reservoir quality coefficient and combined with the logging curves, trajectory data and stratigraphic information of the pilot well and adjacent vertical well, constructs a single-well steering model for adjacent wells; S105 collects logging-while-drilling data, drilling-while-drilling engineering data, and logging parameters, and constructs a horizontal well steering model based on the adjacent well single-well steering model; Real-time logging-while-drilling data, drilling engineering data, and logging parameters are acquired using WITSML; real-time logging-while-drilling data and adjacent well directional models are imported into the horizontal well directional model using LOGXD directional software.

[0041] S106, based on the horizontal well steering model and mechanical specific energy, obtains the mechanical specific energy curve, mechanical drilling rate curve and drilling pressure curve; The reservoir quality coefficient curve is plotted based on the horizontal well steering model. The mechanical specific energy curve is calculated using real-time drilling parameters through the mechanical specific energy model established by Teale. The mechanical drilling rate curve and drilling pressure curve are then loaded.

[0042] S107, based on reservoir quality coefficient, mechanical specific energy curve, mechanical drilling rate curve and drilling pressure curve, selects the positive region of reservoir quality-drilling quality.

[0043] Place the reservoir quality coefficient and mechanical energy specificity curve in the same curve channel, adjust the left and right scales of the reservoir quality coefficient and mechanical energy specificity curves, select overlapping segments with varying lithology, and set the first positive overlap region and the first negative overlap region; place the mechanical drilling rate curve and drilling pressure curve in another curve channel, adjust the left and right scales of the mechanical drilling rate and drilling pressure curves, select overlapping segments with positive correlation between mechanical drilling rate and drilling pressure, and set the second positive overlap region and the second negative overlap region; select the positive region of reservoir quality-drilling quality as: select the first positive overlap region and the second positive overlap region.

[0044] S108 compares the directional models of adjacent wells and horizontal wells in real time, updates and iterates the horizontal well model to perform real-time directional tracking of horizontal wells, and analyzes the positive changes in the trajectory reservoir quality-drilling quality region in real time by combining logging while drilling and drilling engineering parameters.

[0045] See Figure 2 This invention discloses a real-time evaluation system for shale gas horizontal well reservoir quality and drilling quality, comprising: The acquisition module is used to acquire logging data from neighboring wells around the well to be drilled and to perform normalized evaluation on the logging data. A reservoir quality coefficient acquisition module, which acquires the reservoir quality coefficient based on normalized evaluation logging data; A mechanical energy specificity acquisition module, which collects real-time drilling parameters and acquires mechanical energy specificity based on the collected real-time drilling parameters; The adjacent well single-well steering model construction module constructs an adjacent well single-well steering model based on the reservoir quality coefficient and combined with the logging curves, trajectory data, and stratigraphic information of the pilot well and the adjacent vertical well. A horizontal well steering model construction module is provided, which collects logging-while-drilling data, drilling-while-drilling engineering data and logging parameters, and constructs a horizontal well steering model based on the steering model of an adjacent single well. The curve acquisition module acquires the mechanical specific energy curve, mechanical drilling rate curve, and drilling pressure curve based on the horizontal well steering model and mechanical specific energy. The selection module selects the positive region of reservoir quality versus drilling quality based on reservoir quality coefficient, mechanical energy curve, mechanical drilling rate curve and drilling pressure curve. The iterative module compares the directional model of adjacent wells and the horizontal well model in real time, updates and iterates the horizontal well model to perform real-time directional tracking of the horizontal well, and analyzes the positive region changes of the trajectory reservoir quality-drilling quality in real time by combining logging while drilling and drilling engineering parameters.

[0046] Example: See Figure 3 This invention proposes a real-time evaluation method for reservoir quality and drilling quality in shale gas horizontal wells, comprising: I. Reservoir quality evaluation technology includes the following steps: (1) Obtain logging data from neighboring wells near the well to be drilled, including logging curves for evaluating reservoir quality: porosity φ, total organic carbon TOC, total gas content QAL and brittleness index BRIT.

[0047] (2) Normalized logging curves for evaluating reservoir quality: porosity φ, total organic carbon TOC, total gas content QAL and brittleness index BRIT.

[0048] (3) Normalized porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT) are set as indicators N1, N2, ..., N for evaluating reservoir quality. i .

[0049] (4) The independence weighting method is used to determine the strength of collinearity between the above indicators and other indicators to determine the indicator weights. If N i Other indicators The larger the multiple correlation coefficient, the smaller the weight of that indicator. The multiple correlation coefficient can be expressed as:

[0050]

[0051] in, This is the multiple correlation coefficient; For a certain reservoir quality index; This represents the average value of reservoir quality indicators; This is a linear combination of other reservoir quality indicators; , It is a constant.

[0052] (5) Calculate the reciprocal of the multiple correlation coefficient between each index and other indices, and combine the correlation coefficient method to obtain the comprehensive coefficient of each index, and then obtain the weight of the index item for evaluating reservoir quality.

[0053] (6) By normalizing the data, the independence weights of each indicator can be obtained. The independence weights can be expressed as:

[0054] In the formula: The independent weights for each indicator; The correlation coefficient is denoted as .

[0055] (7) The reservoir quality coefficient of shale formations can be expressed using independence weights as follows:

[0056] Where Hg is the reservoir quality coefficient; m is the number of reservoir quality indicators, which is taken as m=4 in this paper; N i These are normalized reservoir quality parameters.

[0057] II. Engineering quality evaluation technology includes the following steps: (1) Drilling engineering parameters include: mechanical parameters, hydraulic parameters, drilling fluid properties and rheological parameters. Mechanical parameters include drilling pressure and rotation speed, etc.; hydraulic parameters include riser pump pressure, displacement and nozzle combination, etc.; drilling fluid properties and rheological parameters include drilling fluid density, viscosity, slice, fluid loss, mud cake, solid content, pH, n value, k value, etc.

[0058] (2) Based on rough set theory, the relative importance of various drilling engineering parameters to the evaluation results is determined by using the positive domain in the rough set. A knowledge expression system C representing drilling efficiency is established. The degree of influence on the decision attribute is evaluated after removing a certain subset of condition attributes from the set of drilling engineering parameters C. If removing the subset of condition attributes will change the drilling efficiency evaluation result accordingly, it indicates that the strength of the subset of condition attributes is high, that is, its importance is high; otherwise, it indicates that the strength of the condition attribute is low, that is, its importance is low.

[0059] (3) By using the method in (2), we can obtain the importance ranking of the attribute evaluation index. From the ranking above, we can know that the mechanical parameter attribute set is the most important, followed by the hydraulic parameters and rheological parameters, and the drilling fluid performance is the worst.

[0060] (4) Evaluation of drilling efficiency is achieved by prioritizing the mechanical parameter attribute set by ranking the importance of evaluation indicators.

[0061] (5) According to Teale’s concept of minimum mechanical specific energy, under the condition of obtaining ideal mechanical drilling speed, the smaller the mechanical specific energy consumed, the more reasonable the applied drilling parameters are, and the more the drill bit is adapted to the formation.

[0062] (6) Input drilling pressure (WOB), rotational speed (RPM), mechanical drilling speed (ROP), torque (T), and drill bit diameter (dbit). Calculate the mechanical specific energy model based on the influence of drill bit pressure and rotation on rock breaking efficiency established by Teale:

[0063] in, WOB Drilling pressure (kN); RPM (rotation speed, r / min); T (torque, kN·m); ROP The drilling speed is mechanical, in m / h; The value is the drill bit diameter, in cm.

[0064] (7) According to the relationship between drilling pressure and mechanical drilling speed, when the drill bit has not fully penetrated the rock, the mechanical drilling speed increases slowly with the increase of drilling pressure; after the drill bit has fully penetrated the formation, the mechanical drilling speed increases rapidly with the increase of drilling pressure; when the rock cuttings at the bottom of the well gradually increase and complex working conditions such as drill bit mud appear at the bottom of the well, the mechanical drilling speed gradually decreases with the increase of drilling pressure, and the vibration of the drill bit increases.

[0065] (8) Based on the relationship between drill bit pressure and mechanical drilling speed, analyze the changes in mechanical specific energy under normal working conditions, and comprehensively judge the quality of drilling project.

[0066] III. Establishing a real-time drilling quality evaluation technology based on the curve overlap method for reservoir quality identification. (1) Using the reservoir quality coefficient, combined with the logging curves, trajectory data and stratigraphic information of the pilot well and the adjacent vertical well, a single-well directional model of the adjacent well is established through directional analysis software.

[0067] (2) WITSML obtains logging-while-drilling data, drilling-while-drilling engineering data, and logging parameters in real time through a remote data center.

[0068] (3) Use LOGXD directional software to import real-time logging data and adjacent well directional models into the horizontal well directional model.

[0069] (4) Plot the reservoir quality coefficient curve in the horizontal well steering model, calculate the mechanical specific energy curve using real-time drilling parameters according to the mechanical specific energy model established by Teale, and load the mechanical drilling rate curve and drilling pressure curve in real time. (5) Place the reservoir quality coefficient and mechanical energy curve in the same curve channel, adjust the left and right scales of the reservoir quality coefficient and mechanical energy curve, select overlapping sections with obvious changes in lithology, and set the region with large reservoir quality coefficient and small mechanical energy as the positive overlap region; the region with small reservoir quality coefficient and large mechanical energy is the negative overlap region. (6) Place the mechanical drilling speed and drilling pressure curves into another curve channel, adjust the left and right scales of the mechanical drilling speed and drilling pressure curves, select the overlapping segments where the mechanical drilling speed and drilling pressure are positively correlated, and set the area with low drilling pressure and high mechanical drilling speed as the positive overlapping area; and the area with high drilling pressure and low mechanical drilling speed as the negative overlapping area.

[0070] (7) If the reservoir quality coefficient and mechanical specific energy of the drilling area are positively overlapping, and the drilling pressure and mechanical drilling speed are positively overlapping, then it is determined to be an area with good reservoir quality and drilling quality.

[0071] (8) By importing real-time drilling gamma, element logging and drilling gamma imaging from the field into the directional software LOGXD through WISML, the geometric relationship between the trajectory and the target layer can be accurately determined, such as geological structure, distance from the interface, dip angle, and upcut / downcut direction, so as to accurately depict the position of the trajectory in the target layer.

[0072] (9) Real-time comparison of adjacent well single-well directional models and horizontal well models, updating and iterating the horizontal well model to perform real-time directional tracking of the horizontal well, and combining real-time analysis of trajectory reservoir quality-drilling quality and real-time drilling encounters with logging and drilling engineering parameters; see [link to relevant documentation] Figure 4 .

[0073] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for real-time evaluation of shale gas horizontal well reservoir quality and drilling quality, characterized in that, include: Collect logging data from neighboring wells around the well to be drilled, and perform normalized evaluation on the logging data; Reservoir quality coefficients are obtained based on well logging data from normalized evaluation. Real-time drilling parameters are collected, and mechanical specific energy is obtained based on the collected real-time drilling parameters; Based on the reservoir quality coefficient, and combined with the logging curves, trajectory data, and stratigraphic information of the pilot well and adjacent vertical wells, a single-well steering model for adjacent wells is constructed. Collect logging-while-drilling data, drilling engineering data, and logging parameters. Based on the adjacent well single-well steering model, construct a horizontal well steering model, specifically as follows: Real-time logging-while-drilling data, drilling engineering data, and logging parameters are acquired using WITSML; real-time logging-while-drilling data and adjacent well directional models are imported into the horizontal well directional model using LOGXD directional software. Based on the horizontal well steering model and mechanical specific energy, the mechanical specific energy curve, mechanical drilling rate curve, and drilling pressure curve are obtained, specifically: The reservoir quality coefficient curve is plotted based on the horizontal well steering model. The mechanical specific energy curve is calculated using real-time drilling parameters through the mechanical specific energy model established by Teale. The mechanical drilling rate curve and drilling pressure curve are then loaded. Based on the reservoir quality coefficient, mechanical energy curve, mechanical drilling rate curve, and drilling pressure curve, the positive region of reservoir quality versus drilling quality is selected, specifically: Place the reservoir quality coefficient curve and mechanical energy curve in the same curve channel, adjust the left and right scales of the reservoir quality coefficient and mechanical energy curve, select overlapping segments with varying lithology, and set the first positive overlap area and the first negative overlap area. Place the mechanical drilling rate curve and drilling pressure curve into another curve channel, adjust the left and right scales of the mechanical drilling rate and drilling pressure curves, select the overlapping segments where the mechanical drilling rate and drilling pressure are positively correlated, and set the second positive overlap area and the second negative overlap area; the selection of the positive area of ​​reservoir quality-drilling quality is: selecting the first positive overlap area and the second positive overlap area. Real-time comparison of the directional models of adjacent wells and horizontal well models, updating and iterating the horizontal well model to perform real-time directional tracking of horizontal wells, and combining logging while drilling and drilling engineering parameters to analyze the positive region changes of trajectory reservoir quality-drilling quality in real time.

2. The real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to claim 1, characterized in that, The logging data of adjacent wells surrounding the well to be drilled includes logging curves for evaluating reservoir quality: porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT).

3. The real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to claim 1, characterized in that, The reservoir quality coefficient is obtained from the well logging data based on normalized evaluation, specifically as follows: Normalized porosity φ, total organic carbon (TOC), total gas content (QAL), and brittleness index (BRIT) were determined as the indicators N1, N2, ..., N for evaluating reservoir quality. i ; Based on the independence weight coefficient method, the collinearity relationship between any indicator and other indicators is determined; Based on the collinearity relationship between any indicator and other indicators, obtain the multiple correlation coefficient between any indicator and other indicators; Based on the correlation coefficient method and the reciprocal of the multiple correlation coefficient between any index and other indicators, the comprehensive coefficient of each index is obtained, and the independence weight of the index items for evaluating reservoir quality is obtained. Based on independence weights, the reservoir quality coefficient of shale formations is obtained.

4. The real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to claim 3, characterized in that, The method for obtaining the multiple correlation coefficient between any indicator and other indicators based on the collinearity relationship between any indicator and other indicators is as follows: If any index N i Other indicators The multiple correlation coefficient is negative; the multiple correlation coefficient is: in, ; In the formula: This is the multiple correlation coefficient; For a certain reservoir quality index; This represents the average value of reservoir quality indicators; This is a linear combination of other reservoir quality indicators; , It is a constant; The independence weights of the indicators for evaluating reservoir quality are as follows: In the formula: The independent weights for each indicator; The correlation coefficient; The reservoir quality coefficient of shale formations is obtained based on independence weights. In the formula: Hg is the reservoir quality coefficient; m is the number of reservoir quality indicators; N i These are normalized reservoir quality parameters.

5. The real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to claim 4, characterized in that, Before obtaining the mechanical specific energy based on the collected real-time drilling parameters, the method further includes: Collect drilling engineering parameters, including mechanical parameters, hydraulic parameters, drilling fluid properties, and rheological parameters; Based on rough set theory, the positive domain of rough set is used to determine the relative importance of mechanical parameters, hydraulic parameters, drilling fluid properties and rheological parameters to the evaluation results, and to obtain the importance ranking of attribute evaluation indicators. The mechanical parameters with the highest importance ranking among the attribute evaluation indicators are selected to evaluate drilling efficiency.

6. The real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to claim 5, characterized in that, The mechanical parameters include drilling pressure and rotational speed; the hydraulic parameters include riser pump pressure, displacement, and nozzle combination; and the drilling fluid properties and rheological parameters include drilling fluid density, viscosity, slice size, fluid loss, mud cake, solids content, and pH.

7. The real-time evaluation method for shale gas horizontal well reservoir quality and drilling quality according to claim 6, characterized in that, The mechanical specific energy is obtained based on the collected real-time drilling parameters, specifically as follows: in, WOB Drilling pressure (kN); RPM (rotation speed, r / min); T (torque, kN·m); ROP The drilling speed is mechanical, in m / h; The value is the drill bit diameter, in cm.

8. A real-time evaluation system for shale gas horizontal well reservoir quality and drilling quality, characterized in that, include: The acquisition module is used to acquire logging data from neighboring wells around the well to be drilled and to perform normalized evaluation on the logging data. A reservoir quality coefficient acquisition module, which acquires the reservoir quality coefficient based on normalized evaluation logging data; A mechanical energy specificity acquisition module, which collects real-time drilling parameters and acquires mechanical energy specificity based on the collected real-time drilling parameters; The adjacent well single-well steering model construction module constructs an adjacent well single-well steering model based on the reservoir quality coefficient and combined with the logging curves, trajectory data, and stratigraphic information of the pilot well and the adjacent vertical well. The horizontal well steering model construction module collects logging-while-drilling data, drilling engineering data, and logging parameters, and constructs a horizontal well steering model based on the steering model of adjacent single wells. Specifically: Real-time logging-while-drilling data, drilling engineering data, and logging parameters are acquired using WITSML; real-time logging-while-drilling data and adjacent well directional models are imported into the horizontal well directional model using LOGXD directional software. The curve acquisition module, based on the horizontal well steering model and mechanical specific energy, acquires the mechanical specific energy curve, mechanical drilling rate curve, and drilling pressure curve, specifically as follows: The reservoir quality coefficient curve is plotted based on the horizontal well steering model. The mechanical specific energy curve is calculated using real-time drilling parameters through the mechanical specific energy model established by Teale. The mechanical drilling rate curve and drilling pressure curve are then loaded. The selection module, based on the reservoir quality coefficient, mechanical energy curve, mechanical drilling rate curve, and drilling pressure curve, selects the positive region of reservoir quality versus drilling quality, specifically: Place the reservoir quality coefficient curve and mechanical energy curve in the same curve channel, adjust the left and right scales of the reservoir quality coefficient and mechanical energy curve, select overlapping segments with varying lithology, and set the first positive overlap area and the first negative overlap area. Place the mechanical drilling rate curve and drilling pressure curve into another curve channel, adjust the left and right scales of the mechanical drilling rate and drilling pressure curves, select the overlapping segments where the mechanical drilling rate and drilling pressure are positively correlated, and set the second positive overlap area and the second negative overlap area; the selection of the positive area of ​​reservoir quality-drilling quality is: selecting the first positive overlap area and the second positive overlap area. The iterative module compares the directional model of adjacent wells and the horizontal well model in real time, updates and iterates the horizontal well model to perform real-time directional tracking of the horizontal well, and analyzes the positive region changes of the trajectory reservoir quality-drilling quality in real time by combining logging while drilling and drilling engineering parameters.

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