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CN-122014201-A - Directional well guiding method based on dynamic lithology profile

CN122014201ACN 122014201 ACN122014201 ACN 122014201ACN-122014201-A

Abstract

A directional well guiding method based on dynamic lithology section relates to the technical field of oil and gas exploration. Before entering a horizontal section of a directional well, converting a time domain lithology section 0 into a depth domain lithology section 0 through an initial velocity field 0, calibrating a depth relation in a pilot well, generating a well point velocity, adding a velocity body, smoothly correcting to obtain a velocity body 1, forming a new depth domain lithology section 1, loading a design track, loading acoustic wave data while drilling into the velocity body 1 after the velocity is converted, comparing and correcting velocity fields 2 obtained by current and X length velocity fields, converting the time domain lithology section 0 into the depth domain lithology section 2 by using the velocity field 2, loading the real drilling depth, comparing the positions of the two sections to obtain an error delta D, adjusting a Y length track in the drilling direction according to the delta D, and returning to an adjustment scheme when necessary. The invention has the beneficial effects of obviously improving the drilling precision and efficiency, overcoming the limitations of the prior art, realizing real-time dynamic adjustment, improving the benefits of resource exploration and development and promoting the innovation and development of the drilling technology.

Inventors

  • HAN HAOTIAN
  • LI ZHONGCHENG
  • DONG CHANGCHUN
  • QU WEIWEI
  • TANG MIN

Assignees

  • 中国石油天然气股份有限公司

Dates

Publication Date
20260512
Application Date
20241111

Claims (10)

  1. 1. The directional well guiding method based on the dynamic lithology profile is characterized by comprising the following steps: S1, before entering a horizontal section starting point of a directional well, converting a time domain lithology section 0 of a well passing track into a depth domain lithology section 0 through an initial velocity field 0; S2, calibrating the time-depth relation of the pilot well, generating the speed at the well point, adding the data into a speed body, performing local smooth correction to obtain a speed body 1, forming a new depth domain lithology section 1, and loading a design track; S3, converting the received acoustic data while drilling into speed, loading the speed data into a speed body 1, comparing the speed data with the speed body, correcting the current speed field and the length speed field of the drilling direction X, and carrying out local smooth correction to form a corrected speed field 2; s4, converting the lithology section 0 in the same time domain into the lithology section 2 in the depth domain through the corrected speed field 2, and loading the current real drilling depth; S5, comparing track positions of the current real drilling point X in the depth domain lithology section 1 and the depth domain lithology section 2 to form error data delta D.
  2. 2. The method of directional well guidance based on dynamic lithology profile according to claim 1, wherein in step S1, the time domain lithology profile 0 of the well trajectory is converted into the depth domain lithology profile 0 via the initial velocity field 0 by the velocity module of the interpretation software before entering the start of the horizontal section of the directional well.
  3. 3. The directional well guiding method based on dynamic lithology section as claimed in claim 1, wherein in step S2, the depth relation of the pilot well is precisely calibrated by using a synthesis recording module, the speed at the well point is generated, the data is added into the speed body to make local smooth correction, the speed body 1 is obtained, a new depth domain lithology section 1 is formed by the speed module of the interpretation software, and the design track is loaded.
  4. 4. The method for guiding a directional well based on a dynamic lithology section according to claim 1, wherein in step S3, after receiving acoustic data while drilling, the seismic interpretation software converts the acoustic data into velocity and loads the velocity into the velocity body 1, compares the velocity fields, corrects the velocity fields of the current and drilling directions X and length, and makes local smoothing correction to form a corrected velocity field 2.
  5. 5. The directional well guiding method based on dynamic lithology profile according to any one of claims 1-4, wherein in step S3, X is 10m or 20m or 30m.
  6. 6. The method of directional well guidance based on dynamic lithology section according to claim 1, wherein in step S4, the same time domain lithology section 0 is converted into depth domain lithology section 2 by using the velocity module of the interpretation software through the corrected velocity field 2 while loading the current real drilling depth.
  7. 7. The method for directional well guidance based on dynamic lithology profile according to claim 1, wherein Y is 10m or 20m or 30m in step S5.
  8. 8. The directional well guiding method based on dynamic lithology profiles of any one of claims 1-4, 6, 7, further comprising a remote data transmission system for receiving, processing and feeding back data.
  9. 9. The method for guiding a directional well based on a dynamic lithology profile according to any one of claims 1 to 4, 6 and 7, wherein in step S5, the next target point and the drilling direction Y length trajectory are corrected.
  10. 10. The method of directional well guidance based on dynamic lithology profiles of claim 9, wherein no adjustment is needed if Δd <20cm, no drilling is affected, and wherein an adjustment scheme is formed and returned to the wellsite if Δd >20 cm.

Description

Directional well guiding method based on dynamic lithology profile Technical Field The invention belongs to the technical field of oil and gas exploration, and relates to a directional well guiding method based on a dynamic lithology section. Background Both risk exploration and conventional pre-exploration are evolving towards profitability, with thinner and thinner target layers. Directional well technology is an important application in this process. For example, chinese patent application publication No. CN118065879a discloses a method for measuring and controlling the curvature of directional well bore in real time. The currently used directional technique is curve fitting, which uses the current real drilling stratum curve (GR, resistivity, etc.) and the pilot well stratum curve to compare, and fits the stratum inclination angle to guide the drilling direction, and the method can only fit a small stratum inclination angle, and once there is a small fault or the stratum speed is suddenly changed, the method can not function, and the method uses the three-dimensional earthquake cross-well section to load the on-site fed back well track data into the three-dimensional earthquake. The method is based on the seismic event, if the effective reservoir thickness is only 5-10m, the control is carried out by using the event of 30-50m, the precision is far from enough, and if the stratum speed is suddenly changed, a larger error can occur and the guiding significance is lost when the stratum speed is suddenly changed and the seismic section is still used. Both of these guiding methods have major limitations with respect to the problems of speed anomalies and thinner reservoirs in parts of the area, parts of the layer system. How to accurately and directionally drill in thin reservoirs and formations with abnormal speeds is a urgent problem to be solved. Disclosure of Invention In order to solve the technical problems in the prior art, the invention provides a directional well guiding method based on a dynamic lithology profile, which tracks the formation speed and the dynamic change of a reservoir in real time through a remote data transmission system, synchronously and dynamically adjusts track data according to the depth domain lithology profile by millisecond-level delay and centimeter-level error, so that a drill bit can stably drill along a target formation all the time. In order to achieve the above purpose, the present invention provides the following technical solutions: a directional well guiding method based on dynamic lithology section comprises the following steps: S1, before entering a horizontal section starting point of a directional well, converting a time domain lithology section 0 of a well passing track into a depth domain lithology section 0 through an initial velocity field 0; S2, calibrating the time-depth relation of the pilot well, generating the speed at the well point, adding the data into a speed body, performing local smooth correction to obtain a speed body 1, forming a new depth domain lithology section 1, and loading a design track; S3, converting the received acoustic data while drilling into speed, loading the speed data into a speed body 1, comparing the speed data with the speed body, correcting the current speed field and the length speed field of the drilling direction X, and carrying out local smooth correction to form a corrected speed field 2; s4, converting the lithology section 0 in the same time domain into the lithology section 2 in the depth domain through the corrected speed field 2, and loading the current real drilling depth; S5, comparing track positions of the current real drilling point X in the depth domain lithology section 1 and the depth domain lithology section 2 to form error data delta D. Further, in step S1, the time domain lithology section 0 of the well trajectory is converted into the depth domain lithology section 0 through the initial velocity field 0 by the velocity module of the interpretation software before entering the beginning of the horizontal section of the directional well. In step S2, the depth relation of the pilot well is precisely calibrated by using the synthesis recording module, the speed at the well point is generated, the data is added into the speed body, the local smooth correction is performed, the speed body 1 is obtained, a new depth domain lithology section 1 is formed by the speed module of the interpretation software, and the design track is loaded. Further, in step S3, after receiving the acoustic data while drilling, the seismic interpretation software converts the acoustic data into velocity, and then loads the velocity into the velocity body 1, and compares the velocity with the velocity field of the current and drilling direction X length velocity field, and performs local smoothing correction to form a corrected velocity field 2. Further, in step S3, X is 10m or 20m or 30m. Further, in step S4, the same time domain l