Sand-mud stone thin interbed reservoir thickness prediction method

Abstract

The invention provides a sand-mud stone thin interbed reservoir thickness prediction method. The sand-mud stone thin interbed reservoir thickness prediction method includes the following steps that: performing fine horizon interpretation; extracting a plurality of kinds of seismic attributes of a thin interbed; optimizing the plurality of kinds of seismic attributes to obtain optimized seismic attributes; performing multiple-attribute fitting; and calculating sand body thickness distribution and outputting results. With the sand-mud stone thin interbed reservoir thickness prediction method adopted, problems such as difficult thin interbed oil reservoir structure interpretation, instable sand body transverse distribution and difficult transverse prediction, can be solved, and distribution trends of thin layers (sand layer groups) on a plane can be precisely described, and relative relationships between thinness and thickness can be indicated.

Description

technical field [0001] The invention relates to the technical field of seismic multi-attribute prediction, in particular to a method for predicting the thickness of thin sand-shale interbedded reservoirs. Background technique [0002] Thin interbedded oil reservoirs are an important exploration type in continental faulted basins. Due to their complex formation mechanism and distribution rules, difficult exploration, and high technical requirements, the research on new technologies and methods for description and evaluation is the key to solving the exploration difficulties of this type of oil and gas reservoirs. inevitable way. However, the technical methods used in the current imported software are still difficult to meet the needs of thin interbedded reservoir exploration. The main problems are as follows: First, thin interbedded reservoirs often have poor structural trap conditions, small faults and micro-amplitude structures are developed, and structural interpretation ...

AI Technical Summary

Problems solved by technology

However, the technical methods used in the current imported software are still difficult to meet the needs of thin interbedded reservoir exploration. The main problems are as follows: First, thin interbedded reservoirs often have poor structural trap conditions, small faults and micro-amplitude structures are developed, and structural interpretation is difficult.

Second, the reservoir development is poor, the layers are thin, and the resolution of the existing seismic data is not enough. The thickness of oil-gas sandstone reservoirs is generally smaller than the seismic resolution limit, which makes the corresponding relationship between the seismic oil-gas response and the actual oil-gas-bearing sandstone (reservoir) layer difficult. Difficult to determine, difficult to identify single sand bodies, very difficult to study seismic oil and gas response models, unstable lateral distribution of sand bodies, difficult to predict laterally

Third, the reservoirs are thin and interbedded, making it difficult to identify oil, gas and water layers

However, in practical work, the effectiveness of attribute extraction is often overlooked, especially the research on thin-layer information extraction methods is not deep enough.

Studies have shown that different attributes have different sensitivities to different lithologies, and play different roles in describing different objects. At the same time, some seismic attributes may have nothing to do with the target layer itself, but reflect shallow disturbances Or the change of the seismic wave absorption by the formation, if various seismic attributes related to reservoir prediction are introduced without analysis, it will have an adverse effect on reservoir prediction

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