Technology for thin layer lithology reservoir recognition and horizontal well drilling tracking

Abstract

The invention relates to the technical field of petroleum exploration and development, in particular to a technology for thin layer lithology reservoir recognition and horizontal well drilling tracking. The technology comprises the steps of applying newly collected three-dimensional seismic data, carrying out comprehensive geological research by combination of well logging of a newly drilled well and production data, studying oil reservoir types and distribution laws, confirming reservoir-controlling factors, and finely depicting a geologic body; utilizing the high-yielding well reflection characteristics to track a favorable sand body, utilizing the fact that a high-yielding well has the reflection characteristics of ranging from points to lines, faces, and bodies on a seismic section, namely the characteristic that sand body updip pinch-out points and horizontal change points form sand body pinch-out lines is obvious, and determining a sand body distribution range in an own style. The thin layer lithology sand body of smaller than 5m can be effectively depicted, the oil reservoir thickness lower limit deployed by a horizontal well is reduced from 5m to 1.6m, and thin layer marginal oil reservoir reserves are effectively applied. The shortcoming that the thin layer marginal oil reservoir reserves cannot be developed in the prior art is overcome.

Description

Technical field: [0001] The invention relates to the technical field of petroleum exploration and development, in particular to a thin-bed lithology reservoir identification and horizontal well drilling tracking technology. Background technique: [0002] At present, most of the oil areas under the jurisdiction of major oilfields have entered the middle and late stage of exploration, and it is becoming more and more difficult to find high-quality large-scale reserves; the developed packaged oilfields have all entered the late stage of high water cut development, and the adjustment and deployment space is getting smaller and smaller. In order to ensure the scale of production, the focus of exploration has gradually shifted from large oilfields to hard-to-recover reserves. However, it is limited by factors such as thin reservoir and small range. First, at present, the prediction is mainly based on the combination of logging data and 3D seismic data, but the prediction accuracy...

AI Technical Summary

Problems solved by technology

It overcomes the deficiency that the existing technology cannot develop the reserves of thin-layer marginal oil reservoirs

[0005] On the basis of confirming the structure and distribution rules of oil layers, and re-understanding the types of reservoirs, in view of the problems of thin-bed overlying reservoirs with small development range and low oil-bearing range of sand bodies, in order to ensure one-time targeting of horizontal wells, pilot wells need to The design is in the stable area where the reservoir is developed in the low part of the structure, the entrance of the horizontal section is designed in the low part, and the horizontal section is designed to be oblique to the structural line, so that the direction dip of the horizontal section is less than 15°; the LWD geosteering instrument produced by Schlumberger is used to improve the Steering accuracy. At the same time, rotary steering is used to pick up the dip angle of the formation. During the drilling process, the angle between the wellbore trajectory and the formation can be judged in real time. When cutting up the formation, it is necessary to reduce the inclination to keep the wellbore trajectory parallel to the formation. The trajectory is parallel to the formation; the LWD geosteering tool can detect the formation resistivity at a distance of 3.8m from the drill bit, and when drilling through the target formation at an angle of 1-2° with the target formation, the well deviation can be adjusted Re-enter the target layer within 10-20m; track the drilling every day after the horizontal well is drilled, understand the drilling depth, the display of cuttings encountered in the interval, the value of all hydrocarbons, and the drilling time, and make corresponding adjustment measures in time to reduce the purpose of drilling. layers of risk