A paleostress inversion method

Abstract

The invention discloses a paleostress inversion method and petroleum geological exploration equipment. The method includes: a data acquisition step, fine interpretation through seismic data, acquisition of fault geometric parameters, activity property analysis for fault classification, fault sliding trend calculation, Deviation calculation and cyclic search to obtain the optimal paleo-stress orientation and relative size, where the paleo-stress recovery step is to select an initial stress state to calculate the sliding trend, calculate the deviation value of the sliding trend and the fault distance distribution under this stress state, through the stress cycle Find the paleo-stress state with the minimum deviation value, which is the ancient stress. The present invention is generally applicable in the field of oil and gas industry, and it can perform paleostress inversion without knowing fault slip direction information by using the fault throw data obtained from seismic interpretation; the obtained data of the present invention is easy to obtain in the field of oil and gas industry, The invention has simple operation, high reliability and good implementability.

Description

technical field [0001] The invention belongs to the technical field of geophysical surveying, and in particular relates to a paleostress inversion method and petroleum geological prospecting equipment. Background technique [0002] In-situ stress is the fundamental force that causes various underground deformations and failures, and its related theories are widely used in all aspects of oil and gas exploration and development. In-situ stress includes in-situ stress in geological history (called ancient in-situ stress) and present in-situ stress. In the field of oil and gas industry, oil and gas migration and accumulation mostly occurred in the paleogeological period, so the prediction of paleostress is of great significance to oil and gas exploration and development. [0003] For example, Chinese patent application CN201711383904.7 discloses a reservoir fracture prediction method based on stress release rate, which analyzes the correlation between mineral content and rock m...

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Problems solved by technology

[0005] At present, many methods are used in paleostress inversion, such as seismic focal mechanism, paleostress markers, and microseismic methods. These methods have strict requirements on field geological outcrops and core data, and need to know the direction of fault slip under stress, but It is difficult to obtain fault slip direction data, especially in the field of oil and gas industry, where fault data are obtained through seismic data interpretation. Geometric information such as fault occurrence and fault distance can be easily obtained during seismic interpretation, but the slip direction cannot be directly obtained. Therefore, the paleostress inversion method based on fault slip direction data is difficult to apply in the oil and gas industry

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