CN-121997513-A - Track design method and related device for sand coal superimposed gas reservoir highly-deviated well

Abstract

The invention belongs to the technical field of natural gas exploration and development, and discloses a track design method and a related device of a sand coal superimposed gas reservoir high-inclination well, wherein the method comprises the steps of obtaining drilled well information in a target area, predicting reservoir plane spreading characteristics and analyzing geological adaptability; and according to the determined optimal track, designing a gas production process, a drilling process and a reconstruction process of the high-inclination well to complete the track design of the sand-coal superimposed gas reservoir high-inclination well. The multi-layer differentiated unconventional sand coal reservoir is utilized to the greatest extent, and the method has the advantages of large inclination, large well control reserves, safe and reliable drilling and production, environmental protection, sustainability and the like. The contact area of the gas storage layer can be effectively enlarged, the gas storage layer can be penetrated better, more oil gas reserves can be obtained, so that unconventional oil gas resources difficult to be mined can be better mined, and the oil gas exploitation efficiency is improved.

Inventors

• WANG YE
• XIA YONGHUI
• WANG YIFEI
• WANG JINGJIAN
• CHEN CUNLIANG
• ZHENG XIAOPENG
• ZHANG BOJIE
• ZHANG ZHENGTAO
• LUO WENQIN
• FAN PING
• HAO LONG
• Meng Peilong
• LU GUIYI
• WANG ZHUNBEI
• CHEN FENGXI
• WANG SHUJIE
• LAN YIFEI
• WANG HUA
• ZHANG FANG
• FEI SHIXIANG
• WU ZHENG
• FENG YANSONG

Assignees

• 中国石油天然气股份有限公司

Dates

Publication Date

20260508

Application Date

20241104

Claims (10)

1. 1. A track design method for a sand coal superimposed gas reservoir highly deviated well, which is characterized by comprising the following steps: acquiring drilled well information in a target area, predicting reservoir plane spreading characteristics and analyzing geological adaptability; according to the reservoir plane spreading characteristics and the geological adaptability, determining the optimal track of each gas-bearing interval in the target area; and designing a gas production process, a drilling process and a transformation process of the high-inclination well according to the determined optimal track, and completing the track design of the sand-coal superimposed gas reservoir high-inclination well.
2. 2. A method of trajectory planning for a sand-gas stacked gas reservoir highly deviated well as claimed in claim 1 wherein the drilled information comprises effective thickness, porosity, permeability and saturation of each of the gas bearing formations of the completed skeletal well.
3. 3. The track design method for the sand-coal stacked gas reservoir highly-deviated well according to claim 1, wherein the prediction method for the reservoir plane spreading characteristics is as follows: And (3) carrying out sorting analysis on the drilled information in the target area, and predicting the plane spreading characteristics of the reservoir in the target area by using a variation function, a kriging technology and a random simulation technology means through a geostatistical method by combining with the comparison of adjacent wells.
4. 4. The method for designing the track of the sand-coal stacked gas reservoir highly-deviated well according to claim 1, wherein the analysis method for the geological adaptability is as follows: According to the prediction result of the reservoir plane spreading characteristics, reservoir parameters of each longitudinal gas-bearing reservoir section are determined, and the combined production reservoir section is determined by combining the interlayer difference coefficients, so that interlayer interference is avoided; The reservoir parameters comprise compact gas-containing sandstone not less than 8m, coal rock thickness not less than 6m, gas-containing layer section vertical depth of 2200-2500 m and vertical thickness of >200m.
5. 5. The method for designing the track of the sand-coal stacked gas reservoir highly-deviated well as set forth in claim 4, wherein the inter-layer difference coefficient is: Where i represents an interval of the formation, i=1, 2,3,.. D i represents the interlayer difference coefficient, P i represents the formation pressure, and K i represents the permeability.
6. 6. The method for designing the track of the highly deviated well of the sand-coal stacked gas reservoir according to claim 1, wherein the process for determining the optimal track of each gas-bearing interval in the target area is as follows: According to the prediction result of the reservoir plane spreading characteristics, different in-situ well deviation is designed by combining reservoir parameters of each longitudinal gas-bearing stratum section, the in-situ well deviation thickness of the gas-bearing stratum section is measured by using a trigonometric function method, the in-situ optimal well deviation is determined, and then the optimal well deviation of each gas-bearing stratum section is sequentially determined according to the vertical depth of the lower gas-bearing stratum section.
7. 7. The track design method for the sand-coal stacked gas reservoir high-inclination well, according to claim 1, is characterized in that the transformation process is partial pressure combination, 3-5 sections are transformed for production of coal-rock sections, and 2-3 sections are transformed for production of multi-layer sand-rock sections.
8. 8. A track design system for a sand-coal stacked gas reservoir highly deviated well, comprising: the acquisition module is used for acquiring drilled well information in a target area, predicting the plane spreading characteristics of the reservoir and analyzing the geological adaptability; The track module is used for determining the optimal track of each gas-bearing interval in the target area according to the reservoir plane spreading characteristics and the geological adaptability; And the design module is used for designing a gas production process, a drilling process and a transformation process of the high-inclination well according to the determined optimal track, so as to complete the track design of the sand-coal superimposed gas reservoir high-inclination well.
9. 9. A terminal device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the steps of the method according to any one of claims 1-7 when the computer program is executed by the processor.
10. 10. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the steps of the method according to any one of claims 1 to 7.

Description

Track design method and related device for sand coal superimposed gas reservoir highly-deviated well Technical Field The invention belongs to the technical field of natural gas exploration and development, and relates to a track design method and a related device for a sand-coal superimposed gas reservoir high-inclination well. Background The eastern part of the Erdos basin is taken as one of the important energy bases in China, the multilayer sandstone gas reservoirs are wide in distribution range, the reserves are thick, a series of development technologies are formed in recent years, and benefit development is achieved. However, with the gradual advancement of exploration and development, gas reservoirs in the new fields of longitudinally stacked coal rock, limestone and the like also have certain potential. These new areas of gas reservoirs have significant differences in geologic features, reservoir characteristics, and fluid properties from sandstone reservoirs, and therefore, conventional development techniques and well options may not be fully applicable. Reasonable well type selection is a problem facing all gas field development processes, the current compact sandstone gas reservoir development mode has undergone three stages, from early stage 'da Cong straight/directional well group' to 'single-layer horizontal well development aiming at a dominant zone' to 'three-dimensional horizontal well development exploration', and benefit development is realized for multi-layer laminated gas reservoirs, single-main-force layer gas reservoirs and multi-main-force layer gas reservoirs respectively. With the initial development of potential of gas reservoirs in new fields such as coal rock, limestone and the like, new well tests such as high inclination and the like need to be actively developed, and new ways of benefit development are explored. At present, research and development and application of highly deviated well technologies are also more and more widespread at home and abroad, but the technologies are only aimed at single coal and rock reservoirs, or sand coal multi-type unconventional gas reservoirs are developed by adopting horizontal wells, and well types are not developed by taking the cooperation of sand rocks and coal and rock gas reservoirs into consideration. The requirements of efficient and fine development of multi-layer system superimposed sand coal multi-type unconventional gas reservoirs on well type selection and deployment modes are continuously improved, so that the geological reserves of the multi-layer system superimposed sand coal multi-type unconventional gas reservoirs are effectively utilized to ensure the optimal matching of geological targets and development modes, the recovery ratio is improved, and the development of the optimization design of highly-deviated wells is urgent. Disclosure of Invention The invention aims to provide a track design method and a related device for a sand-coal stacked gas reservoir high-inclination well, which solve the problem that the prior art does not consider the collaborative development and utilization of multiple resources of sand and coal stacked gas reservoirs. In order to achieve the purpose, the invention is realized by adopting the following technical scheme: A track design method for a sand coal superimposed gas reservoir highly deviated well, comprising: acquiring drilled well information in a target area, predicting reservoir plane spreading characteristics and analyzing geological adaptability; according to the reservoir plane spreading characteristics and the geological adaptability, determining the optimal track of each gas-bearing interval in the target area; and designing a gas production process, a drilling process and a transformation process of the high-inclination well according to the determined optimal track, and completing the track design of the sand-coal superimposed gas reservoir high-inclination well. Further, the drilled information includes an effective thickness, porosity, permeability, and saturation of each of the gas bearing layers of the completed formation. Further, the prediction method of the reservoir plane spreading characteristics comprises the following steps: And (3) carrying out sorting analysis on the drilled information in the target area, and predicting the plane spreading characteristics of the reservoir in the target area by using a variation function, a kriging technology and a random simulation technology means through a geostatistical method by combining with the comparison of adjacent wells. Further, the analysis method of the geological adaptability comprises the following steps: According to the prediction result of the reservoir plane spreading characteristics, reservoir parameters of each longitudinal gas-bearing reservoir section are determined, and the combined production reservoir section is determined by combining the interlayer difference coefficients, so that interlayer interferen