Three-dimensional target tracking drilling method

Abstract

The invention belongs to the technical field of petroleum drilling processes, and particularly provides a three-dimensional target tracking drilling method which adopts a sliding guide combination for drilling. Carrying out three-dimensional geological modeling, quantitatively determining the scale of the river channel according to the migration characteristics of the river channel in different periods, carrying out omnibearing three-dimensional seismic trajectory prediction and real-time guidance, and adjusting a corresponding reservoir target spot; the drilling track is adjusted according to the conditions that the top and the bottom are out of layers, the gas content of the sand body becomes poor, and the sand body is pinched out or laterally out of a river channel, and reservoir tracking drilling is completed; the problems that according to existing horizontal section drilling, after a target point is given, horizontal drilling is designed according to a track, the drilling encounter rate of a reservoir is reduced due to drilling encounter mudstone, sand body pinching and reservoir missing, the drilling construction efficiency is low, and the development cost is high are solved. According to the method, the reservoir target body is transversely adjusted, the reservoir target body is tracked through horizontal section'turning 'drilling, the reservoir of the central beach of the river channel is tracked through transverse adjustment of the target body when the reservoir encounters the river beach and drills out of the river channel, the drilling rate of the reservoir is increased, and the development cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil drilling technology, and particularly relates to a three-dimensional target tracking drilling method. Background Art

[0002] During the drilling process of the reservoir in the horizontal section of a horizontal well, the exploration and development of the reservoir mainly focuses on finding point bars and channel sand bodies. However, due to sedimentary environment and geological changes, the reservoir is thin, the lateral variation of sand bodies is fast, the gas content becomes poor, and the sand bodies pinch out and other changes in gas reservoir reservoirs, resulting in low drilling construction efficiency in the horizontal section, low drilling encounter rate of reservoir sand bodies, and increased development costs.

[0003] The existing horizontal section reservoir drilling has the following deficiencies: After a given target point is set in the existing horizontal section drilling, horizontal drilling is carried out according to the trajectory design. Encountering mudstone, sand body pinch-out, and reservoir loss leads to a decrease in the reservoir drilling encounter rate, a decrease in drilling construction efficiency, and an increase in development costs.

[0004] Chinese patent document with the publication number CN116341045A discloses a three-dimensional target horizontal well trajectory design method, which is specifically implemented as follows: Classify the wells that require three-dimensional target trajectory design for horizontal wells; Through the calculation and analysis of the actual drilling friction and torque, optimize the design parameters of the first build point, build section, tangent section, azimuth change point, second build point, and horizontal swing azimuth point of the horizontal well trajectory to minimize the drilling friction and torque of the three-dimensional target horizontal well and form an optimized design of the three-dimensional target horizontal well trajectory. It solves the problem in the prior art that the wellbore profile design cannot meet the requirements due to the migration of the main sand body not being in the same azimuth. This document designs the trajectory after a given target point, and the target point position is not adjusted during drilling. Summary of the Invention

[0005] The purpose of the three-dimensional target tracking drilling method provided by the present invention is to overcome the problems in the prior art that in the horizontal section drilling, after a given target point is set, horizontal drilling is carried out according to the trajectory design, and encountering mudstone, sand body pinch-out, and reservoir loss leads to a decrease in the reservoir drilling encounter rate, a decrease in drilling construction efficiency, and an increase in development costs.

[0006] To this end, the present invention provides a three-dimensional target tracking drilling method, including the following steps:

[0007] S1. Drill using a sliding steering assembly;

[0008] S2. Conduct three-dimensional geological modeling, adjust the corresponding reservoir target points according to the migration characteristics of different river channels, quantitatively determine the river channel scale, predict the three-dimensional seismic trajectory in all directions and real-time steering.

[0009] S3. Based on reservoir geological sedimentation, 3D geological modeling, and the adjusted reservoir target points, focusing on the spatial distribution law of reservoir sand bodies, for the situations of top and bottom out-of-layer, deterioration of gas-bearing property of sand bodies, sand body pinch-out, or lateral channel emergence, adjust the drilling trajectory to complete reservoir tracking drilling.

[0010] Preferably, in step S2, the 3D geological modeling is specifically as follows: Based on the sedimentary characteristics of the reservoir area, using the inter-well 3D seismic prediction and the actual drilling situation of horizontal wells, anatomize the reservoir sand bodies step by step to establish a 3D geological model.

[0011] Preferably, the actual drilling situation of the horizontal well includes real-time logging-while-drilling parameters, logging parameters, and drilling parameters.

[0012] Preferably, the logging parameters include drilling time, gas logging, and cuttings, the logging parameters include natural gamma and resistivity, and the drilling parameters include well inclination, azimuth, vertical depth, and displacement.

[0013] Preferably, the sliding steering assembly adopts a small-bore directional well single-bend screw oscillation drilling tool assembly.

[0014] Preferably, the adjustment of the drilling trajectory in step S3 includes two adjustment methods, and the two adjustment methods are adjusting the well inclination to control the vertical depth of the target body to track the reservoir and adjusting the azimuth to control the offset distance of the target body to track the reservoir.

[0015] Preferably, adjusting the well inclination to control the vertical depth of the target body to track the reservoir is: By increasing or decreasing the well inclination, adjust the vertical depth of the target body, and vertically adjust to track the reservoir target body.

[0016] Preferably, adjusting the azimuth to control the offset distance of the target body to track the reservoir is: Horizontally adjust laterally to track the reservoir target body.

[0017] Preferably, when the situations of top and bottom out-of-layer, deterioration of gas-bearing property of sand bodies, and sand body pinch-out occur, adjust the well inclination to control the vertical depth of the target body to track the reservoir.

[0018] Preferably, when the situation of lateral channel emergence occurs, adjust the azimuth to control the offset distance of the target body to track the reservoir.

[0019] Advantages of the present invention:

[0020] 1. The three-dimensional target tracking drilling method provided by the present invention solves the problems of low reservoir sandstone encounter rate and low drilling construction efficiency caused by problems such as encountering mudstone, drilling out the top and bottom of the reservoir, reservoirs with poor gas content, pinch-out of reservoir sand bodies or lateral channel exits, etc. Moreover, for the first time, lateral adjustment of the reservoir target is implemented, realizing "turning" drilling in the horizontal section to track the reservoir target. When drilling across the river beach or out of the river channel, the lateral adjustment of the target is used to track the channel bar reservoir, greatly improving the reservoir encounter rate, providing strong technical support for the efficient exploration and development of the reservoir in the horizontal section of horizontal wells, and having good market application prospects.

[0021] 2. The three-dimensional target tracking drilling method provided by the present invention uses a sliding guidance combination for drilling, which has mature technology, simple operation, and has the advantage of low cost.

[0022] 3. The three-dimensional target tracking drilling method provided by the present invention conducts three-dimensional geological modeling, adjusts the corresponding reservoir target points according to the migration characteristics of river channels in different periods, quantitatively determines the scale of river channels, predicts three-dimensional seismic trajectories in all directions and real-time guidance; fully combines geology and seismology to accurately judge and analyze the genetic type, scale, shape, and trend of the encountered sand bodies, providing guidance for the precise control of the reservoir target during the horizontal section drilling process, and greatly improving the reservoir encounter rate.

[0023] 4. The three-dimensional target tracking drilling method provided by the present invention uses azimuth adjustment to control the offset distance of the target to track the reservoir. For the first time, lateral adjustment of the reservoir target is realized, that is, "turning" target pursuit drilling in the horizontal section, solving the problems of encountering the river beach and drilling out of the river channel in the horizontal section. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described in detail below with reference to the drawings.

[0025] Figure 1 It is a schematic diagram of the target penetrating the top and bottom of the reservoir;

[0026] Figure 2 It is a schematic diagram of the vertical depth of the target being adjusted vertically downward;

[0027] Figure 3 It is a horizontal projection diagram of the lateral adjustment of the reservoir target in the horizontal section;

[0028] Figure 4 It is a real-time drilling trajectory tracking diagram of Well J XX-69H1;

[0029] Figure 5 It is a cross-sectional view of the three-dimensional geological modeling model of lithofacies and gas saturation of Well J XX-44H1;

[0030] Figure 6 It is a real-time drilling trajectory tracking diagram of Well J XX-44H1;

[0031] Figure 7 It is the horizontal projection map of the lateral "turning" of the horizontal section of Well J XX-22H1 to pursue the target;

[0032] Figure 8 It is the three-dimensional stereoscopic projection map of the lateral "turning" of the horizontal section of Well J XX-22H1 to pursue the target;

[0033] Figure 9 It is the horizontal projection map of the lateral "turning" of the horizontal section of Well SN XXX-07HST to pursue the target. Specific implementation manner

[0034] The principles and features of the present invention will be described below in conjunction with the accompanying drawings.

[0035] Example 1:

[0036] A three-dimensional target tracking drilling method includes the following steps:

[0037] S1. Drilling is carried out using a sliding steering assembly;

[0038] Preferably, the sliding steering assembly uses a single-bend screw oscillating drilling tool assembly for small-diameter directional wells. Specifically, a single-bend screw oscillating drilling tool assembly for small-diameter directional wells is shown in (ZL201921394040.3), which includes a PDC bit, a single-bend screw, a hydraulic oscillator, a back pressure valve, an MWD directional joint, a non-magnetic drill collar, a transition joint, a heavy drill pipe, and a regular drill pipe connected in sequence from bottom to top, and is equipped with an MWD wireless logging-while-drilling instrument that matches the natural gamma system. It has mature technology, simple operation, and the advantage of low cost.

[0039] S2. Three-dimensional geological modeling is carried out. According to the migration characteristics of river channels in different periods, the scale of river channels is quantitatively determined, and three-dimensional seismic trajectories are predicted and real-time guided in all directions to adjust the corresponding reservoir targets;

[0040] Preferably, in step S2, the three-dimensional geological modeling is specifically: based on the sedimentary characteristics of the reservoir area, using the three-dimensional seismic prediction between wells and the actual drilling situation of horizontal wells, the reservoir sand bodies are anatomized step by step to establish a three-dimensional geological model.

[0041] Preferably, the actual drilling situation of the horizontal well includes real-time logging-while-drilling parameters, logging parameters, and drilling parameters.

[0042] Preferably, the logging parameters include drilling time, gas logging, and cuttings, the logging parameters include natural gamma and resistivity, and the drilling parameters include well inclination, azimuth, vertical depth, and displacement.

[0043] Specifically, for the 3D geological modeling, multi-source information such as the completed well data of adjacent wells, 3D seismic data volume, stacking velocity spectrum, and interpretation results are used as constraint conditions. The "combination of determination and randomness, hierarchical phase control, and seismic constraint" technology is adopted to establish a high-precision 3D geological model. The real-time logging while drilling, logging, and drilling parameters are imported into the established 3D geological model to determine the spatial position of the drill bit, analyze the genetic type, scale, shape, and trend of the sand body encountered currently, and combine with the actual drilling situation to predict and guide the trajectory in a timely manner, guiding the horizontal section drilling. By fully combining geology and seismic data, the genetic type, scale, shape, and trend of the sand body encountered can be accurately judged and analyzed, providing guidance for the precise control of the reservoir target body during the horizontal section drilling process, and greatly improving the reservoir encounter rate.

[0044] S3. Based on the reservoir geological deposition, 3D geological modeling, and the adjusted reservoir target points, focusing on the spatial distribution law of the reservoir sand body, for the situations of top and bottom out-of-layer, poor gas-bearing property of the sand body, sand body pinch-out, or lateral channel emergence, adjust the drilling trajectory to complete the drilling.

[0045] Preferably, the adjustment of the drilling trajectory in step S3 includes two adjustment methods, which are adjusting the well inclination to control the vertical depth of the target body to track the reservoir and adjusting the azimuth to control the offset distance of the target body to track the reservoir.

[0046] Preferably, adjusting the well inclination to control the vertical depth of the target body to track the reservoir means: adjusting the vertical depth of the target body by increasing or decreasing the well inclination, and vertically adjusting to track the reservoir target body.

[0047] Preferably, adjusting the azimuth to control the offset distance of the target body to track the reservoir means: horizontally adjusting laterally to track the reservoir target body.

[0048] Preferably, when the situations of top and bottom out-of-layer, poor gas-bearing property of the sand body, and sand body pinch-out occur (see Figure 1 and Figure 2 ), adjust the well inclination to control the vertical depth of the target body to track the reservoir. Solve the problems of top and bottom out-of-layer, poor gas-bearing property of the sand body, and sand body pinch-out.

[0049] Preferably, when the situation of lateral channel emergence occurs (see Figure 3 ), adjust the azimuth to control the offset distance of the target body to track the reservoir. Solve the problem of lateral channel emergence.

[0050] The present invention is used in the efficient exploration and development process of the horizontal section of Sulige gas exploration horizontal wells to solve problems such as encountering mudstone, drilling out the top and bottom of the reservoir, reservoirs with poor gas content, pinch-out of reservoir sand bodies or lateral channel exits, which lead to low reservoir sandstone drilling encounter rate and low drilling construction efficiency. Moreover, for the first time, lateral adjustment of the reservoir target body is implemented, realizing "turning" drilling in the horizontal section to track the reservoir target body. When drilling through the river beach or out of the channel, through lateral adjustment of the target body, the channel point bar reservoir is traced, and the reservoir drilling encounter rate is greatly improved, providing strong technical support for the efficient exploration and development of the reservoir in the horizontal section of horizontal wells, and having good market application prospects.

[0051] Example 2:

[0052] Based on Example 1,

[0053] When situations such as drilling out of the top and bottom of the layer, deterioration of the gas content of the sand body, and pinch-out of the sand body occur, the well inclination is adjusted to control the vertical depth of the target body to track the reservoir, solving the problems of drilling out of the top and bottom of the layer, deterioration of the gas content of the sand body, and pinch-out of the sand body.

[0054] A three-dimensional target tracking drilling method, using a sliding guide combination for drilling;

[0055] When poor gas logging shows in the reservoir, the reservoir is missing, or the sand body is pinch-out during drilling, three-dimensional geological modeling is carried out. According to the migration characteristics of channels in different periods, quantitatively determining the scale of the channel, predicting three-dimensional seismic trajectories in all directions and real-time steering, controlling the well inclination during drilling, accurately adjusting the vertical depth of the target body, and tracking the effective gas-bearing sandstone reservoir.

[0056] For example, when drilling in the horizontal section of Well J XX-69H1 to a well depth of 3945 m and the horizontal section length is 520 m, there is no gas logging show, and mudstone is encountered ( Figure 4 Point A in the middle), the sandstone reservoir is missing. By reducing the well inclination to 88° and lowering the vertical depth to explore the reservoir, drilling to a well depth of 4195 m, the vertical depth is lowered by 3 m, and the lower developed gas-bearing tight sandstone reservoir is successfully encountered ( Figure 4 Point B in the middle). The horizontal section length of this well is 1841 m, the reservoir drilling encounter rate is 84.2%, the effective reservoir drilling encounter rate is 49.0%, and the open flow potential is 99,800 m³ / day.

[0057] When the reservoir sand body is pinch-out during drilling, three-dimensional geological modeling is carried out. According to the migration characteristics of channels in different periods, quantitatively determining the scale of the channel, predicting three-dimensional seismic trajectories in all directions and real-time steering, controlling the well inclination during drilling, accurately adjusting the vertical depth of the target body, and tracking the effective gas-bearing sandstone reservoir (new horizon).

[0058] For example, in Well J XX-44H1, through small layer correlation analysis of geology, the three-dimensional seismic conventional stack section shows a weak wave peak at Point A ( Figure 5), indicating that the reservoir sand body in the lower part of He 8 may pinch out, and the reservoir sand body in the lower part of He 8-1 will develop subsequently. After the horizontal section is drilled to 300 m, the lithology changes from light gray gas-bearing fine sandstone to gray mudstone, and the gamma ray (GR) value while drilling suddenly increases to more than 150 API. It is judged that the target layer is missing, and it is decided to adjust the well inclination to 91.5 - 92° to explore the reservoir at a large well inclination. After the vertical depth rises by 13 m, the reservoir in the lower part of He 8-1 is encountered ( Figure 6 ). The horizontal section of this well is 1,620 m long, with 1,193 m of sandstone, and the sandstone encounter rate is 73.64%. The effective reservoir is 1,021 m, and the effective reservoir encounter rate is 63.02%. The open flow potential is 443,800 m³ / day.

[0059] Example 3:

[0060] Based on Example 1,

[0061] When there is a lateral channel, the azimuth is adjusted to control the offset of the target to track the reservoir and solve the problem of lateral channels.

[0062] A three-dimensional target tracking drilling method uses a sliding steering assembly for drilling; three-dimensional geological modeling is carried out. According to three-dimensional seismic analysis, the direction of river channel change is predicted, and the offset is adjusted horizontally by twisting the azimuth in the horizontal section to achieve "turning" tracking of the reservoir during horizontal section drilling.

[0063] For example, when drilling the J XX-22H1 well to a depth of 4,235 m, the gas logging shows low, and argillaceous sandstone is encountered. According to three-dimensional seismic analysis, a river beach is encountered, and the direction of river channel change is predicted. By twisting the azimuth of the horizontal section from 0° to 335.5°, with a 24.5° azimuth twist, when drilling to a depth of 4,635 m, the gas logging shows obvious, and the lithology gradually changes from argillaceous sandstone to gas-bearing fine sandstone, successfully achieving reservoir target tracking ( Figure 7 ). The azimuth of the horizontal section of J XX-22H1 twists and swings by 25°. The horizontal section is 1,872 m long, and the sandstone encounter rate is 100%. The effective reservoir encounter rate is 74%. It realizes azimuth twisting in the horizontal section to track the river channel reservoir target during drilling, greatly improving the reservoir encounter rate ( Figure 8 ).

[0064] For example, when the horizontal section of the SN XXX-07HST horizontal well is drilled to a depth of 4,676 m, the horizontal section is 800 m long, and the length of the mudstone section encountered is 200 m. The offset is re-tracked by horizontally adjusting the offset by twisting the azimuth in the horizontal section. First, twist the azimuth to the right by 10 - 15°, and then twist the azimuth to the left by 25° to track and find the gas-bearing sandstone in the river channel reservoir, achieving "turning" tracking of the reservoir target during horizontal section drilling. The horizontal section of this well is deepened to 1,680 m, and the sandstone encounter rate in the horizontal section reaches 100% after "turning" to track the reservoir target ( Figure 9 ).

[0065] In the description of the present invention, it should be understood that if there are terms such as "front", "inside", "right", etc., indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and should not be construed as a limitation of the present invention.

[0066] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. Any design identical or similar to the present invention falls within the scope of protection of the present invention.

Claims

1. A three-dimensional target tracking drilling method, characterized in that: It includes the following steps: S1. Drilling is carried out by using a sliding guiding combination; S2. Three-dimensional geological modeling is carried out. According to the migration characteristics of river channels in different periods, the scale of river channels is quantitatively determined, and the three-dimensional seismic trajectory of the whole direction is predicted and real-time guided to adjust the corresponding reservoir target points; S3. Based on the reservoir geological deposition, three-dimensional geological modeling and the adjusted reservoir target points, focusing on the spatial distribution law of reservoir sand bodies, for the situations of top and bottom out-of-layer, poor gas-bearing property of sand bodies, sand body pinch-out or lateral river channels, the drilling trajectory is adjusted to complete the reservoir tracking drilling.

2. The three-dimensional target tracking drilling method according to claim 1, characterized in that: The three-dimensional geological modeling in step S2 is specifically as follows: Based on the sedimentary characteristics of the reservoir area, using the three-dimensional seismic prediction between wells and the actual drilling situation of horizontal wells, the reservoir sand bodies are anatomized step by step to establish a three-dimensional geological model.

3. The three-dimensional target tracking drilling method according to claim 2, characterized in that: The actual drilling situation of the horizontal well includes real-time logging-while-drilling parameters, logging parameters and drilling parameters.

4. The three-dimensional target tracking drilling method according to claim 3, wherein: The logging parameters include drilling time, gas logging and cuttings, the logging parameters include natural gamma and resistivity, and the drilling parameters include well inclination, azimuth, vertical depth and displacement.

5. The three-dimensional target tracking drilling method according to claim 1, characterized in that: The sliding guiding combination adopts a single-bend screw oscillation drilling tool combination for slimhole directional wells.

6. The three-dimensional target tracking drilling method according to claim 1, characterized in that: The adjustment of the drilling trajectory in step S3 includes two adjustment methods, and the two adjustment methods are adjusting the well inclination to control the vertical depth of the target body to track the reservoir and adjusting the azimuth to control the offset distance of the target body to track the reservoir.

7. The three-dimensional target tracking drilling method according to claim 6, characterized in that: Adjusting the well inclination to control the vertical depth of the target body to track the reservoir means: adjusting the vertical depth of the target body by increasing or decreasing the well inclination, and vertically adjusting to track the reservoir target body.

8. The three-dimensional target tracking drilling method according to claim 6, wherein: Adjusting the azimuth to control the offset distance of the target body to track the reservoir means: horizontally adjusting laterally to track the reservoir target body.

9. The three-dimensional target tracking drilling method according to claim 7, characterized in that: When the situations of top and bottom out-of-layer, poor gas-bearing property of sand bodies and sand body pinch-out occur, adjusting the well inclination to control the vertical depth of the target body to track the reservoir is adopted.

10. The three-dimensional target tracking drilling method according to claim 8, characterized in that: When the situation of lateral river channels occurs, adjusting the azimuth to control the offset distance of the target body to track the reservoir is adopted.

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