Method, medium and equipment for predicting leakage of permian igneous rock

Abstract

The invention relates to the technical field of oil exploration and development, in particular to a method, medium and equipment for predicting permian igneous rock leakage, and the method comprises the steps: collecting the data of an adjacent drilled well; well-seismic calibration is completed; and summarizing the reflection characteristics of the Yingan rock and tuff layer sections of the drilled well, predicting the distribution of the Yingan rock and the tuff according to the reflection characteristics of the to-be-drilled well, and further predicting the permian igneous rock leakage well section. According to the method, the well drilling data and the seismic data are combined, and the lateral change of the seismic data is utilized to predict the development conditions of the permian Inan rock and the tuff, so that the leakage prediction precision is improved. Compared with the prior art that the position of the leaked section is detected after drilling, the method has the advantages that prediction of the to-be-drilled permian igneous rock leakage section is achieved, the leakage risk is predicted for drilling engineering, the drilling engineering can respond in advance, the drilling difficulty is reduced, and the drilling efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil exploration and development, and specifically provides a method, medium and device for predicting Permian igneous rock leakage. Background Art

[0002] At the present stage, well leakage is a common phenomenon in most oilfields at home and abroad. Well leakage can lead to increased operating costs and delays in the construction period. At the same time, the plugging fluid used after leakage will pollute the reservoir, resulting in the logging curve being unable to reflect the true formation information, bringing great difficulties to the identification of formation fluids in the later stage.

[0003] In the Permian igneous rocks in the Shunbei area, due to the development of porphyritic reservoir in dacite and the looseness of tuff, leakage often occurs when drilling through dacite and tuff, which will cause drilling well control risks. In the early stage, it was mainly predicted based on the drilling situation of adjacent wells. However, due to the large lateral variation of igneous rocks, the prediction error of igneous rock lithology is large.

[0004] In the Chinese invention patent with the application publication number CN 116150695 A and the application publication date of May 23, 2023, a method for determining the leakage position of drilling fluid and calculating leakage parameters is disclosed, which is used to find the position where well leakage occurs during drilling, calculate the leakage rate and leakage volume of drilling fluid to estimate the leakage scale. The present invention expounds the principle that the photoelectric absorption cross-section Pe value of barite contained in drilling fluid is abnormally high compared with any other rock, mineral and fluid, accurately locates the leakage position through the high-value characteristics of the Pe curve measured by litho-density logging in the leakage interval, predicts the leakage rate by using the correlation between the Pe logging value and the instantaneous leakage rate, and calculates the leakage volume by combining the method of multi-mineral analysis with the actual content of barite in drilling fluid. The existing methods are usually for determining the leakage position of drilling fluid in drilled wells, and cannot predict the distribution of dacite and tuff according to the reflection characteristics of the well to be drilled, and further predict the leakage interval of Permian igneous rocks.

[0005] Therefore, there is an urgent need for a method, medium and device for predicting Permian igneous rock leakage. Summary of the Invention

[0006] To avoid the above problems existing in the prior art, the purpose of the present invention is to provide a method, medium and device for predicting Permian igneous rock leakage.

[0007] To achieve the above purpose, the present invention provides the following technical solutions: A method for predicting Permian igneous rock leakage, comprising the following steps:

[0008] S1: Collect data of adjacent drilled wells;

[0009] S2: Perform well-seismic calibration;

[0010] S3: Summarize the reflection characteristics of the drilled dacite and tuff intervals, predict the distribution of dacite and tuff based on the reflection characteristics of the well to be drilled, and further predict the lost circulation intervals of the Permian igneous rocks.

[0011] The present invention is further configured such that the data in step S1 includes the acoustic travel time curve and density logging curve of the drilled wells, the interface depths of the Permian, Carboniferous, and Silurian systems, the lithology and depth data of the Permian igneous rocks, the time-migrated seismic data volume, and the interpreted top layer data of the Permian and Carboniferous systems.

[0012] The present invention is further configured such that step S2 is specifically to calibrate the positions of the Permian and Carboniferous interfaces on the seismic section by making synthetic seismograms.

[0013] The present invention is further configured such that the synthetic seismograms are made by applying the acoustic travel time, density data curves, seismic data, and layer data of the logging on a conventional seismic comprehensive interpretation software.

[0014] The present invention is further configured such that the reflection characteristics in step S3 include reflection intensity and reflection continuity. The reflection intensity is judged by the amplitude value of the seismic data, and the reflection continuity is judged by the lateral change shape.

[0015] The present invention is further configured such that the seismic reflection characteristics of the dacite interval are that the amplitude value of the seismic data is within the range of 12.5% of the amplitude value of the seismic data volume at the two extreme values of the amplitude value range of the seismic data volume, and the lateral change is in an interval shape or a wavy shape.

[0016] The present invention is further configured such that the seismic reflection characteristics of the tuff interval are that the amplitude value of the seismic data is within the range of ±12.5% of the median value of the amplitude value range of the seismic data volume, and the lateral change is in a straight line shape.

[0017] The present invention is further configured such that step S3 is specifically to observe the reflection characteristics through the seismic section of the well to be drilled. If the amplitude value of the seismic data is within the range of 12.5% of the amplitude value of the seismic data volume at the two extreme values of the amplitude value range of the seismic data volume, and the lateral change is in an interval shape or a wavy shape, it is predicted that the Permian of the well to be drilled develops dacite, the dacite reservoir is developed, and lost circulation is likely to occur during the drilling process;

[0018] If the reflection characteristics observed through the seismic section of the well to be drilled are that the amplitude value of the seismic data is within the range of ±12.5% of the median value of the amplitude value range of the seismic data volume, and the lateral change is in a straight line shape, it is predicted that the Permian of the well to be drilled develops tuff, the tuff is prone to fracture-induced lost circulation, and attention should be paid to controlling the mud density during the drilling process.

[0019] It should be noted that after summarizing the reflection characteristics of the drilled Permian basalt and completing the calibration of the synthetic seismogram, the seismic reflection characteristics of the dacite formation are summarized as strong reflection intensity and poor continuity, and the seismic reflection characteristics of the tuff are summarized as weak reflection intensity and good continuity. The size of the reflection intensity refers to the strength of the amplitude of the seismic data. Good continuity means small lateral changes, and poor continuity means large lateral changes. In conventional interpretation, it is all identified by the human eye.

[0020] The present invention also includes an electronic device, and the electronic device includes:

[0021] A memory storing executable instructions;

[0022] A processor that runs the executable instructions in the memory to implement the above method for predicting Permian igneous rock leakage.

[0023] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the above method for predicting Permian igneous rock leakage.

[0024] In summary, the beneficial effects of the above technical solutions of the present invention are as follows:

[0025] 1. By combining the drilled data and seismic data, the present invention uses the lateral changes of seismic data to predict the development of Permian dacite and tuff, thereby improving the accuracy of leakage prediction. Compared with the prior art that detects the position of the leaked section after drilling, the present invention realizes the prediction of the leakage section of Permian igneous rock in the well to be drilled, predicts the leakage risk for the drilling project, enables the drilling project to respond in advance, reduces the drilling difficulty, and improves the drilling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0027] Figure 1 It is a flowchart of a method for predicting Permian igneous rock leakage according to the present invention.

[0028] Figure 2 It is a schematic diagram of a seismic profile of the distribution of Permian dacite in Embodiment 1 of the present invention.

[0029] Figure 3 It is a schematic diagram of a seismic profile of the distribution of Permian tuff in Embodiment 1 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0030] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Based on the embodiments in the present invention, other similar embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0031] In addition, the direction words mentioned in the following embodiments, such as "up", "down", "left", "right", etc. are only references to the directions in the accompanying drawings. Therefore, the direction words used are for illustration rather than for limiting the present invention.

[0032] The present invention will be further described below in conjunction with the accompanying drawings and preferred embodiments.

[0033] Embodiment 1:

[0034] As Figure 1 shown, it is a preferred embodiment of the present invention. A method for predicting the loss of Permian igneous rocks includes the following steps:

[0035] S1: Collect data of adjacent drilled wells;

[0036] The data includes the acoustic travel-time curve and density log curve of the drilled well, the interface depths of the Permian, Carboniferous, and Silurian systems, the lithology and depth data of the Permian igneous rocks, the time-migrated seismic data volume, and the interpreted top layer data of the Permian and Carboniferous systems.

[0037] S2: Perform well-seismic calibration;

[0038] On the conventional seismic comprehensive interpretation software, use the acoustic travel-time, density data curve, seismic data, and layer data of the well to make the synthetic seismic record. By making the synthetic seismic record, calibrate the positions of the Permian and Carboniferous interfaces on the seismic section; as Figures 2 - 3 shown.

[0039] S3: Summarize the reflection characteristics of the rhyolite and tuff intervals in the drilled wells, predict the distribution of rhyolite and tuff according to the reflection characteristics of the well to be drilled, and then predict the lost well intervals of the Permian igneous rocks.

[0040] The reflection characteristics described in step S3 include reflection intensity and reflection continuity; the reflection intensity is judged by the amplitude value of the seismic data, and the reflection continuity is judged by the lateral change shape.

[0041] Summarize the seismic reflection characteristics of the rhyolite interval according to the reflection characteristics of the rhyolite and tuff intervals in the drilled wells. The seismic reflection characteristics of the rhyolite interval are that the amplitude value of the seismic data is within the 12.5% seismic data amplitude value range at the two extreme values of the seismic data amplitude value range, and the lateral change is in an interval shape or a wavy shape.

[0042] The seismic reflection characteristics of the tuff layer are that the amplitude value of the seismic data is within the range of the median value of the amplitude values of the seismic data volume ±12.5%, and the lateral variation is linear.

[0043] As Figure 2 shown, by observing the reflection characteristics through the seismic profile of the well to be drilled, the reflection intensity is large, the continuity is poor, and the lateral variation is intermittent or wavy. It can be judged that the Permian system of the well to be drilled develops dacite, the dacite reservoir is developed, and lost circulation is likely to occur during the drilling process; Figure 2 In [Figure], area A is the area where the actual drilled lithology in the adjacent drilled well is mainly dacite, and area B is the predicted distribution area of dacite in the well to be drilled.

[0044] As Figure 3 shown, the reflection characteristics observed through the seismic profile of the well to be drilled are that the reflection intensity is small, the continuity is good, and the lateral variation is linear. It is predicted that the Permian system of the well to be drilled develops tuff, and the tuff is prone to fracture and lost circulation. Pay attention to controlling the mud density during the drilling process. Figure 3 In [Figure], area C is the area where the actual drilled lithology in the adjacent drilled well is mainly tuff, and area D is the predicted distribution area of tuff in the well to be drilled.

[0045] It should be noted that the size of the reflection intensity refers to the strength of the amplitude of the seismic data, and the amplitude is dimensionless. It only represents the relative size. The amplitude value ranges of different processed data are different. In the present invention, the reflection intensity is described by a proportional range.

[0046] Taking the amplitude value range of an 8-bit seismic data volume from -127 to 128 in general as an example, the ±12.5% amplitude value range of the seismic data volume at the 0 value, that is, the seismic data volume amplitude value within -32 to 32 is generally weak amplitude, that is, the reflection intensity is small, while the 12.5% amplitude value range of the seismic data volume close to -127 or 128, that is, the seismic data volume amplitude value within -95 to -127 or 96 to 128 is considered strong amplitude, that is, the reflection intensity is large. Good continuity means small lateral variation, approaching a linear shape, and poor continuity means large lateral variation, with the lateral variation being intermittent or wavy, which is judged by manual visual recognition in conventional interpretation.

[0047] Example 2:

[0048] An electronic device, the electronic device includes:

[0049] A memory storing executable instructions;

[0050] A processor that runs the executable instructions in the memory to implement the above-mentioned method for predicting lost circulation of Permian igneous rocks.

[0051] Example 3:

[0052] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned method for predicting Permian igneous rock leakage is implemented.

[0053] The above are only the preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the idea of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, several improvements and refinements made without departing from the principle of the present invention should also be regarded as within the protection scope of the present invention.

Claims

1. A method for predicting Permian igneous rock losses, characterized in that, It includes the following steps: S1: Collect data of adjacent drilled wells; S2: Conduct well-seismic calibration; S3: Summarize the reflection characteristics of the dacite and tuff intervals in the drilled wells, predict the distribution of dacite and tuff based on the reflection characteristics of the well to be drilled, and then predict the lost circulation intervals of the Permian igneous rocks.

2. The method for predicting Permian igneous rock leakage according to claim 1, wherein The data described in step S1 includes the acoustic travel time curve and density logging curve of the drilled wells, the interface depths of the Permian, Carboniferous, and Silurian systems, the lithology and depth data of the Permian igneous rocks, the time-migrated seismic data volume, and the interpreted top layer data of the Permian and Carboniferous systems.

3. A method for predicting Permian igneous rock leakage according to claim 2, characterized in that, Step S2 specifically is to calibrate the positions of the Permian and Carboniferous interfaces on the seismic profile by making synthetic seismograms.

4. A method for predicting Permian igneous rock loss according to claim 3, characterized in that, Apply the acoustic travel time, density data curve, seismic data, and layer data of the well logging to make the synthetic seismogram on the conventional seismic comprehensive interpretation software.

5. A method for predicting Permian igneous rock leakage according to claim 4, characterized in that, The reflection characteristics described in step S3 include reflection intensity and reflection continuity. The reflection intensity is judged by the amplitude value of the seismic data, and the reflection continuity is judged by the lateral variation shape.

6. The method for predicting Permian igneous rock leakage according to claim 5, characterized in that The seismic reflection characteristics of the dacite interval are that the amplitude value of the seismic data is within the range of 12.5% of the amplitude value of the seismic data volume at the two extreme values in the amplitude value range of the seismic data volume, and the lateral variation is in an interval or wavy shape.

7. A method for predicting Permian igneous rock loss according to claim 6, characterized in that, The seismic reflection characteristics of the tuff interval are that the amplitude value of the seismic data is within the range of ±12.5% of the median value of the amplitude value of the seismic data volume in the amplitude value range of the seismic data volume, and the lateral variation is in a straight line shape.

8. A method for predicting Permian igneous rock leakage according to claim 7, characterized in that, Step S3 specifically is to observe the reflection characteristics through the seismic profile of the well to be drilled. If the amplitude value of the seismic data is within the range of 12.5% of the amplitude value of the seismic data volume at the two extreme values in the amplitude value range of the seismic data volume, and the lateral variation is in an interval or wavy shape, then predict that the Permian system of the well to be drilled develops dacite, the dacite reservoir is developed, and lost circulation is likely to occur during the drilling process; If the reflection characteristics observed through the seismic profile of the well to be drilled are that the amplitude value of the seismic data is within the range of ±12.5% of the median value of the amplitude value of the seismic data volume in the amplitude value range of the seismic data volume, and the lateral variation is in a straight line shape, then predict that the Permian system of the well to be drilled develops tuff, and the tuff is prone to fracture-induced lost circulation.

9. An electronic device, characterized in that, The electronic device includes: A memory storing executable instructions; A processor that runs the executable instructions in the memory to implement a method for predicting lost circulation of Permian igneous rocks according to any one of claims 1-8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements a method for predicting lost circulation of Permian igneous rocks according to any one of claims 1-8.

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