A method for correcting horizontal well tracking seismic profiles

Abstract

The present invention discloses a method for correcting a horizontal well tracking seismic profile. By using the actual drilled formation data of the currently determined target horizontal well, adjacent wells, and related wells, and combining with 3D seismic data, the trend data reflected by the seismic and the possible trend data of the real formation are obtained, and the seismic profile is corrected by using the difference in the plane position of the two trend data. By making full use of various information such as seismic, logging, and drilling in horizontal well tracking, the seismic velocity field is not required in the correction process, reducing the uncertainty and error caused by data conversion and data smoothing that may exist in the correction process, ensuring the correction accuracy and reliability, and the fast correction speed meets the timeliness requirements of on-site tracking.

Description

Technical Field

[0001] The invention relates to the technical field of horizontal well geophysical tracking, in particular to a method for correcting a seismic profile of a horizontal well tracking. Background Art

[0002] The implementation of shale gas horizontal wells is very technically difficult. First of all, the well trajectory control is difficult. For most of China's shale gas exploration and development areas, the thickness of the best quality shale is not as thick as imagined. For example, the best quality shale of the Longmaxi Formation in southern Sichuan, with a TOC of 4%, a gas content of 4m3 / t, and a porosity of more than 6%, is only a few meters to more than ten meters thick. In order to ensure that after the implementation of the horizontal well, hydraulic fracturing can transform the best quality shale to the greatest extent and form the largest possible effective transformation volume, it is necessary to let the horizontal well trajectory pass through the high-quality shale according to the set position, and the vertical deviation shall not exceed 3 or 4 meters, which is very difficult to control.

[0003] Tracking, adjusting and controlling the horizontal well trajectory by using the formation reflection information of seismic data is an important part of horizontal well drilling tracking. High-quality and accurate seismic data can more accurately reflect the ups and downs of high-quality shale formations. The horizontal well track is drilled in the depth domain according to the seismic reflection axis information, and can pass through the high-quality shale according to the predetermined target. However, since the propagation of the seismic wave field itself is a very complex process, the imaging obtained by collecting and processing seismic waves does not directly reflect the situation of the geological body, but is only a response of the geological body in the seismic wave field. Due to the complexity of the geological body itself, the complexity of the propagation of the seismic wave field, and the complexity of seismic imaging, the formation ups and downs information reflected by the seismic wave may be different from the actual ups and downs of the high-quality shale formation. In order to enable seismic data to guide the drilling of horizontal wells more accurately and reliably, the seismic profile needs to be corrected.

[0004] In the prior art, seismic profile correction is usually performed based on seismic wave field velocity, which has high requirements on velocity. The effect of correction is basically determined by the reliability of the velocity model. For some problems that are not caused by the velocity deviation of the seismic wave field, correction based on velocity is not only difficult to achieve the ideal effect, but also lacks rationality. At the same time, the correction process is relatively complicated, time-consuming and labor-intensive, and has low timeliness. Summary of the invention

[0005] The purpose of the present invention is to provide a method for horizontal well tracking seismic profile correction to address the problems in the prior art of high speed requirements, difficult to ensure reliability, complicated correction process and low timeliness in seismic profile correction based on seismic wave field velocity.

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

[0007] A method for correcting a horizontal well tracking seismic profile, comprising the following steps:

[0008] S100 For the target horizontal well in the target work area, select adjacent wells and related wells, and obtain the actual drilled formation data of the target horizontal well and adjacent wells and related wells;

[0009] S200 According to the 3D seismic data of the target work area, obtain the 3D spatial variation data of the formation and the trend data reflected by the seismic;

[0010] S300 According to the actual drilled formation data of the target horizontal well and adjacent wells and related wells, as well as the 3D spatial variation data of the formation, determine the possible trend data of the true formation;

[0011] S400 Correct the seismic profile according to the possible trend data of the true formation and the trend data reflected by the seismic.

[0012] A method for correcting a horizontal well tracking seismic profile, using the actual drilled formation data of the currently determined target horizontal well and adjacent wells and related wells, combined with 3D seismic data, to obtain the trend data reflected by the seismic and the possible trend data of the true formation, and using the difference in the plane position of the two trend data to correct the seismic profile. By making full use of the seismic, logging, drilling and other information in horizontal well tracking, the correction process does not require the use of a seismic velocity field, reducing the uncertainty and error caused by data conversion and data smoothing that may exist in the correction process, ensuring the correction accuracy and reliability, and the fast correction speed meets the timeliness requirements of on-site tracking.

[0013] Preferably, the method for obtaining the actual drilled formation data of the target horizontal well in step S100:

[0014] The currently drilled formation of the target horizontal well includes the corresponding target formation and the upper formation, and the actual drilled formation data is obtained through logging technology, horizontal well logging while drilling and related means.

[0015] Preferably, the method for obtaining the actual drilled formation data of adjacent wells and related wells in step S100:

[0016] The actual drilled formation of adjacent wells and related wells includes the corresponding target formation and the upper formation, and the actual drilled formation data is obtained through logging technology, horizontal well logging while drilling and related means.

[0017] Preferably, in step S200, the 3D spatial variation data of the formation is obtained by layer tracking and interpretation of the target horizon from 3D seismic data in the time domain or spatial domain.

[0018] Preferably, step S300 includes:

[0019] S310 obtains the initial trend data of the real formation based on the actual drilled formation data of the target horizontal well, adjacent wells, and related wells;

[0020] S320 determines whether the initial trend data of the real formation is consistent with the trend data reflected by the seismic data. If they are consistent, the initial trend data of the real formation is determined as the possible trend data of the real formation; if not, it proceeds to step S330;

[0021] S330 analyzes the influencing factors causing the difference based on the three-dimensional spatial change data of the formation, and after removing the influencing factors, obtains the possible trend data of the real formation.

[0022] Preferably, the influencing factors include:

[0023] the deviation of imaging velocity, the deviation of migration effect, the influence of overlying formation faults, the influence of lithology changes in the overlying formation, the influence of other geological anomalies in the overlying formation, and the influence of lateral inhomogeneity of the target formation.

[0024] Preferably, the step S400 includes:

[0025] S410 matches the trend data reflected by the seismic data to the possible trend data of the real formation, and determines the numerical difference at each position of the two trend data;

[0026] S420 performs up and down translation on the seismic data traces corresponding to each planar position according to the numerical differences at each planar position of the two trend data, so that each seismic target reflection corresponds to the possible trend data of the real formation, and completes the correction of the seismic profile.

[0027] An electronic device includes at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and when the instructions are executed by the at least one processor, the at least one processor is enabled to execute the method described in any one of the above.

[0028] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are:

[0029] A method for correcting a horizontal well tracking seismic profile of the present invention utilizes the actual drilled formation data of the currently determined target horizontal well, adjacent wells, and related wells, and combines with 3D seismic data to obtain the trend data reflected by the seismic and the possible trend data of the real formation, and corrects the seismic profile by using the difference in the plane position of the two trend data. By making full use of various information such as seismic, logging, and drilling in horizontal well tracking, the correction process does not require the use of a seismic velocity field, reducing the uncertainty and error caused by data conversion and data smoothing that may exist in the correction process, ensuring the correction accuracy and reliability, and the fast correction speed meets the timeliness requirements of on-site tracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic flow chart of the method for correcting a horizontal well tracking seismic profile of the present invention.

[0031] Figure 2 is a schematic flow chart for obtaining the possible trend data of the real formation.

[0032] Figure 3 is a schematic diagram of the uncorrected seismic profile in Embodiment 1.

[0033] Figure 4 is a schematic diagram of the uncorrected 3D seismic data in the spatial domain in Embodiment 1.

[0034] Figure 5 is a schematic diagram of the uncorrected 3D seismic data in the depth domain in Embodiment 1.

[0035] Figure 6 is a schematic diagram of the corrected 3D seismic data in the depth domain in Embodiment 1.

[0036] Figure 7 is a schematic structural diagram of the electronic device provided by the present invention.

[0037] Markings in the figure: 1 - overlying formation fault, 2 - target horizontal well. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The present invention will be described in detail below with reference to the accompanying drawings.

[0039] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] As Figure 1 shown, a method for correcting a horizontal well tracking seismic profile includes the following steps:

[0041] S100 Select adjacent wells and related wells for the target horizontal well 2 in the target work area, and obtain the actual drilled formation data of the target horizontal well 2 and its adjacent wells and related wells; among them, the formations that have been actually drilled and determined for the target horizontal well 2 include the corresponding target formation and the upper formation, and the actual drilled formation data is obtained through logging technology, gamma ray while drilling for horizontal wells and related means; the actual drilled formations of the adjacent wells and related wells include the corresponding target formation and the upper formation, and the actual drilled formation data is obtained through logging technology, gamma ray while drilling for horizontal wells and related means.

[0042] S200 Obtain the three-dimensional spatial variation data of the formation and the trend data reflected by the seismic based on the three-dimensional seismic data of the target work area; the three-dimensional spatial variation data of the formation is obtained by horizon tracking and interpretation of the target horizon from three-dimensional seismic data in the time domain or spatial domain.

[0043] S300 Determine the possible trend data of the true formation based on the actual drilled formation data of the target horizontal well 2 and its adjacent wells and related wells, and the three-dimensional spatial variation data of the formation; specifically, as Figure 2 shown, it includes steps S310 - S330:

[0044] S310 Obtain the initial trend data of the true formation based on the actual drilled formation data of the target horizontal well 2 and its adjacent wells and related wells.

[0045] S320 Determine whether the initial trend data of the true formation is consistent with the trend data reflected by the seismic. If it is consistent, it means that the seismic and the actual drilled formation are in good agreement and no correction is required, that is, determine the initial trend data of the true formation as the possible trend data of the true formation; if it is not consistent, then go to step S330.

[0046] S330 If there are local or overall differences in the trends reflected by the seismic and the actual drilled formation (the differences can be judged by setting a difference threshold), analyze the influencing factors causing the differences based on the three-dimensional spatial variation data of the formation, and after removing the influencing factors, obtain the possible trend data of the true formation. Among them, the influencing factors include one or more of the following: deviation of imaging velocity, deviation of migration effect, influence of faults in the overlying formation, influence of lithology changes in the overlying formation, influence of other geological anomalies in the overlying formation, influence of lateral inhomogeneity of the target formation. In this embodiment, as Figure 3 shown, the initial trend data of the true formation is not consistent with the trend data reflected by the seismic. Analyze that the influencing factor is the influence brought by the overlying formation fault 1 in the figure, and its influence is as Figure 4 、 Figure 5 shown. Therefore, after removing the influence brought by the overlying formation fault 1, the correction is as Figure 6 shown.

[0047] The S400 corrects the seismic profile according to the possible trend data of the real formation and the trend data reflected by the seismic data.

[0048] Specifically, it includes steps S410 - S420:

[0049] S410 matches the trend data reflected by the seismic data to the possible trend data of the real formation, with the goal that the trend reflected by the seismic data can completely match the possible trend of the real formation, and determines the numerical difference between the two trend data at each position.

[0050] S420 performs vertical translation on the seismic data traces corresponding to each planar position according to the numerical difference between the two trend data at each planar position. After operating on all the seismic data traces, the target reflection of each seismic trace corresponds to the possible trend data of the real formation, and the correction of the seismic profile is completed.

[0051] As Figure 7 shown, according to an exemplary embodiment of the present invention, an electronic device (such as a computer server with program execution function) includes at least one processor, a power supply, and a memory and an input / output interface communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and when the instructions are executed by the at least one processor, the at least one processor is enabled to execute the method disclosed in any of the foregoing embodiments; the input / output interface may include a display, a keyboard, a mouse, and a USB interface for inputting and outputting data; the power supply is used to provide electrical energy for the electronic device.

[0052] Those skilled in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps including the above method embodiments; and the foregoing storage medium includes: removable storage devices, read-only memory (ROM), magnetic disks, or optical disks and other various media that can store program codes.

[0053] When the above integrated unit of the present invention is implemented in the form of a software functional unit and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the embodiments of the present invention essentially or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the methods described in the various embodiments of the present invention. And the foregoing storage medium includes: removable storage devices, ROM, magnetic disks, or optical disks and other various media that can store program codes.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for correcting a horizontal well tracking seismic profile, characterized in that, It includes the following steps: S100: For the target horizontal well in the target work area, select adjacent wells and related wells, and obtain the actual drilled formation data of the target horizontal well, adjacent wells, and related wells; S200: Based on the 3D seismic data of the target work area, obtain the 3D spatial change data of the formation and the trend data reflected by the seismic; the 3D spatial change data of the formation is obtained by layer tracking and interpretation of the target horizon from 3D seismic data in the time domain or spatial domain; S300: Based on the actual drilled formation data of the target horizontal well, adjacent wells, and related wells, and the 3D spatial change data of the formation, determine the possible trend data of the real formation; S400: Correct the seismic profile according to the possible trend data of the real formation and the trend data reflected by the seismic, and the correction process does not depend on the seismic velocity field; The step S400 includes: S410: Match the trend data reflected by the seismic to the possible trend data of the real formation, and determine the numerical difference at each position of the two trend data; S420: According to the numerical difference at each planar position of the two trend data, translate the seismic data trace corresponding to each planar position up and down, so that each seismic target reflection corresponds to the possible trend data of the real formation, and complete the correction of the seismic profile.

2. The method for correcting a horizontal well tracking seismic profile according to claim 1, characterized in that, The method for obtaining the actual drilled formation data of the target horizontal well in the step S100: The formation currently drilled and determined in the target horizontal well includes the corresponding target formation and the upper formation, and the actual drilled formation data is obtained through logging technology, gamma ray while drilling in horizontal wells and related means.

3. A method for correcting a horizontal well tracking seismic profile according to claim 1, characterized in that, The method for obtaining the actual drilled formation data of adjacent wells and related wells in the step S100: The formations actually drilled in adjacent wells and related wells include the corresponding target formation and the upper formation, and the actual drilled formation data is obtained through logging technology, gamma ray while drilling in horizontal wells and related means.

4. A method for correcting a horizontal well tracking seismic profile according to any one of claims 1-3, characterized in that, The step S300 includes: S310: Based on the actual drilled formation data of the target horizontal well, adjacent wells, and related wells, obtain the initial trend data of the real formation; S320: Determine whether the initial trend data of the real formation is consistent with the trend data reflected by the seismic. If it is consistent, determine the initial trend data of the real formation as the possible trend data of the real formation; if it is not consistent, go to step S330; S330: Analyze the influencing factors causing the difference according to the 3D spatial change data of the formation, and after removing the influencing factors, obtain the possible trend data of the real formation.

5. A method for correcting a horizontal well tracking seismic profile according to claim 4, characterized in that, The influencing factors include: Deviation of imaging velocity, deviation of migration effect, influence of overlying formation faults, influence of lithology changes in overlying formations, influence of other geological anomalies in overlying formations, influence of lateral inhomogeneity of target formations.

6. An electronic device, characterized in that, It includes at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method according to any one of claims 1 to 5.

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