Depth domain constraint inversion method based on horizontal well horizontal section vertical shaft virtualization

Abstract

The invention relates to a depth domain constraint inversion method based on a horizontal well horizontal section vertical shaft virtualization. The method includes: setting sampling points at intervals on a horizontal well when drilling, according to the design trajectory, of the horizontal well meets a sand body; calculating the XY ground coordinates of the sampling points projecting to the ground and the horizontal displacement amount, relative to a wellhead, of the sampling points, and building a vertical shaft file and setting the same as the sampling point coordinates; extracting the horizontal section log data in the front and rear 10 meters of the sampling points along the drilling direction, sorting the extracted log data according to the log vertical depth in an ascending manner, and deleting repeated vertical depth values and the corresponding log data; loading the vertical depth values and log data after extraction, sorting and deletion to the newly created vertical shaft file so as to form a virtual vertical shaft; respectively extracting log data according to the set sampling points and form a series of virtual vertical shafts to participate in inversion calculation. The method has the advantages that the data of the horizontal sections are continuously applied to inversion prediction through vertical shaft virtualization, the burial depth and thickness variation of the target sand body in front of a drill bit are predicted timely, and trajectory adjustment is facilitated.

Description

technical field [0001] The invention belongs to the technical field of reservoir prediction, and relates to a method for using logging data of a horizontal section of a horizontal well to participate in constrained inversion through a virtual vertical well. Background technique [0002] In the early stage of horizontal well implementation, it is often necessary to carry out constrained inversion technology based on the actual drilling information of pilot wells to predict the top structure and bottom structure trend of the target sand body, and design the horizontal well trajectory based on the predicted spatial distribution and buried depth change of the target sand body. As far as the current implementation of horizontal wells is concerned, the logging data of the horizontal section of the horizontal well cannot be used in the inversion prediction process. The main reason is that the logging data of the horizontal section is not perpendicular to the ground. When the horizon...

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Problems solved by technology

[0003] The purpose of the present invention is to provide a depth-domain constrained inversion method based on the virtual vertical well of the horizontal section of the horizontal well, so as to solve the problem that the logging data of the horizontal section cannot be effectively used and the drilling risk is extremely high

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