Three-dimensional point-by-point well depth design method

Abstract

The present invention provides a point-line-surface three-dimensional point-by-point well depth design method, comprising: using the old data of the work area to perform tomographic inversion on different offset segments to obtain a near-surface forward modeling model; designing forward modeling and simulating shallow seismic line acquisition parameters; Seek the velocity correspondence of the inversion model of the shallow seismic line and correct it; search for the velocity interface of the excited lithology layer on the basis of the corrected tomographic inversion model of the shallow seismic line; carry out 1km*1km micro-logging investigation in the work area , lithological stratification one by one, and three-dimensional interpolation into the well depth design map. The same parameter tomographic inversion is performed on the old data of the 3D work area, and the results of step 5 are constrained to be corrected; the 3D point-by-point excitation well depth design and mapping are carried out constrained by the old data of the work area and the tomographic inversion of shallow seismic lines. This method can effectively guarantee the rationality and accuracy of well depth design for mountain data excitation, thereby improving the quality of acquired seismic data and laying a good foundation for subsequent improvement of imaging accuracy of pre-stack depth migration.

Description

technical field [0001] The invention relates to the technical field of oilfield development, in particular to a point-line-plane three-dimensional point-by-point well depth design method. Background technique [0002] The surface undulations and surface structure of mountainous areas vary greatly. Due to the influence of complex conditions on the surface, near the surface, and underground, interference waves develop in areas with low signal-to-noise ratio, and the quality of seismic data is poor. The problem of static correction that affects the processing effect of seismic data is very prominent. , so the importance of surface structure investigation is undoubted, and accurate investigation results can also provide accurate basis for well depth design. At present, the mainstream mountain surface survey method is to use the encounter observation method or the chasing shot observation method in the small refraction method according to the conventional density, and only use th...

AI Technical Summary

Problems solved by technology

The thickness and velocity of low and low-speed zones are complex and changeable. The traditional small refraction and micro-logging methods have low accuracy in surface structure surveys, and it is difficult to establish an accurate near-surface model of the piedmont zone. The depth of the excitation well designed based on this is inaccurate. , affecting the quality of seismic data and the subsequent near-surface correction

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