Reservoir thickness prediction method based on dipolar wavelet

Abstract

The invention discloses a prediction method for reservoir thickness which is based on dipole wavelet. Steps are as follows, parameters are extracted, time difference of sound wave between a reservoir and a non-essential reservoir as well as the density are resolved; the time difference of sound wave and the density are converted into a time domain by time-depth conversion, the reflectances of the top and bottom of the reservoir are computed, and a time domain model at the well point is set up, the velocity of longitudinal wave, the density, the wave impedance, and the reflectances are involved in the time domain model; the seismic wavelet is extracted and optimized; a seismic responsing pattern store of reservoir is built by the following steps, the seismic wavelet is taken as a basic wavelet function, the reflectances of the top and bottom of the reservoir are respectively coefficients c and d of the dipole wavelet function to be inputs of the dipole wavelet function, and a reservoir seismic responsing pattern store with a given reservoir section of the work area is set up, spectrum of reservoir thickness is set up; the distribution of the reservoir in three dimensions is predicated quantitatively.

Description

technical field [0001] The invention relates to a reservoir prediction method related to oil or natural gas storage in the prediction formation, in particular to a reservoir thickness prediction method based on dipole wavelet. Background technique [0002] The underground strata are mostly distributed in layers, and they are formed by sediments in different geological periods through deposition, burial, compaction, diagenesis, etc., as well as long-term geological processes such as structural deformation, weathering, and erosion in the later period. At the same time, the dead animals and plants are encased in soil and sand and buried underground together. Under certain underground warm conditions, the buried organic matter undergoes a series of biochemical, catalytic, and other degradation processes. It becomes natural gas and oil. After the generated oil and gas are migrated and stored in storage spaces such as pores, cracks, and caves, they are preserved when the sealing ...

AI Technical Summary

Problems solved by technology

[0016] To sum up, the main shortcomings of reservoir prediction at this stage are: the reservoir prediction by wave impedance inversion has multiple solutions; the spectrum decomposition has multiple extreme values ​​due to the fixed time window and the mixing of high and low frequency information. The thickness interpretation is not unique, the interpretation is difficult, and there are few successful examples of transforming from a tuning body to a reservoir thickness body; the wavelet transform is not pertinent, the thin layer resolution limit is insufficient, and the energy group is not concentrated enough

Images