Multilayer sandstone reservoir low-resistivity oil layer identification method and device

Abstract

The invention provides a multilayer sandstone reservoir low-resistivity oil layer identification method and device. The method comprises the steps that a target exploration zone is subjected to reservoir stratum type classification according to seismic data and subjected to oil-water layer identification, and a questionable low-resistivity oil layer is determined; according to the trap formation, the oil and gas reservoir type of the position of the questionable low-resistivity oil layer is determined; the oil and gas reservoir type is subjected to accumulation mechanism analyzing treatment, and whether the accumulation condition of the oil and gas reservoir type is met or not is judged; if yes, all sand bodies in the position of the questionable low-resistivity oil layer are subjected to unit subdivision with oil and gas reservoirs as units; and in a single oil and gas reservoir, the seal level elevation of the questionable low-resistivity oil layer and the oil-water interface of the reservoir where the questionable low-resistivity oil layer is located are read, and the oiliness of the questionable low-resistivity oil layer is identified. According to the embodiments of the invention, the low-resistivity oil layer in the single oil and gas reservoir can be identified, and the multilayer sandstone reservoir low-resistivity oil layer identification precision can be effectively improved.

Description

technical field [0001] The application belongs to the field of reservoir logging evaluation in the exploration and development of clastic rock oil and gas reservoirs, in particular to a method and device for identifying low-resistivity oil layers in multi-layer sandstone reservoirs based on accumulation analysis. Background technique [0002] Multi-layer sandstone reservoirs are mainly developed in continental strata, widely distributed in major oil and gas fields in my country, and account for a large proportion of reserves. Multiple layers of sandstone are vertically stacked in the reservoir, separated by mudstone. In some cases, the mudstone itself is the source rock, forming a self-generation, self-storage and self-sealing combination with the sand body. Multi-layer sandstone reservoirs generally develop low-resistivity oil layers of various origins. Compared with normal oil layers, their resistivity is lower, even lower than that of water layers. It is difficult to id...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a low-resistivity oil layer identification method based on accumulation analysis in order to solve the problem that the existing low-resistivity oil layer identification method pays attention to the research on the characteristics of single well logging curves, the thinking is single, and the results often have multiple solutions. Using various data to conduct multi-well research on oil and gas reservoirs through accumulation analysis, and identify low-resistivity oil layers in a single oil and gas reservoir, can effectively improve the identification accuracy of low-resistivity oil layers in multi-layer sandstone reservoirs

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