Non-linear chaos algorithm-based reef reservoir identification method

Abstract

The invention relates to a non-linear chaos algorithm-based reef reservoir identification method. The non-linear chaos algorithm-based reef reservoir identification method comprises the steps of 1, deducing a non-linear inversion algorithm; 2, introducing a chaos algorithm; and 3, identifying and forecasting reef reservoir according to an inversion result. On the basis of an earthquake non-linearinversion theory, a Lyapunov index in chaos is introduced during the process of deducing an inversion iterative equation again, the resolution and the stability in inversion are equalized by a regularization factor and a relaxation factor, the reef reservoir can be finally and clearly imaged, and an inversion speed result is obtained. By building an inversion forecast mode of different lithologiesand lithology identification quantity version, the reef reservoir forecast is guided, and the purpose of identifying and forecasting the reef reservoir is finally achieved.

Description

technical field [0001] The invention belongs to the technical field of petroleum exploration reservoir prediction, and in particular relates to a method for identifying biological reef reservoirs based on seismic inversion. Background technique [0002] The distribution of carbonate rocks accounts for about 20% of the total area of ​​sedimentary rocks in the world, and the contained oil and gas reserves account for more than 50% of the total oil and gas reserves. Up to 90% of the world's oil and gas reserves are found in marine strata. It occupies an important position in high-yield oil and gas fields. Carbonate reservoirs have various sedimentary types, complex diagenesis, deep burial and strong heterogeneity. The main problem in carbonate oil and gas exploration is reservoir identification, and the theory and technology involved in its identification and prediction are world-class problems. The research on earthquake prediction of carbonate reservoirs in foreign countrie...

AI Technical Summary

Problems solved by technology

[0004] There are three shortcomings in the existing technical methods: (1) Carbonate reefs have special shapes, large thickness variations, strong heterogeneity, and complex contact relationship with surrounding rocks. There is no inversion for the prediction of reef reservoirs at present Technical research; (2) The current inversion results of conventional software are very dependent on the initial wave impedance conditions of a single well, and have high requirements for formations. (3) The seismic nonlinear inversion method in the prior art, although the resolution of the seismic inversion is improved and the calculation speed is fast, the covariance matrix in the method is mostly an ill-conditioned matrix , the inversion algorithm is unstable, and it is easy to fall into the trap of local optimum in the solution, and cannot reach the global optimal solution

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