Carbonate rock diagenetic environment evolution history recovery method

Abstract

The invention provides a carbonate rock diagenetic environment evolution history recovery method. The method comprises the following steps: acquiring a rock sample for recovery of a work area diagenetic environment evolution history; determining the periods of carbonate diagenetic minerals in the rock sample and the types of the carbonate diagenetic minerals in each period; carrying out isotope dating on the carbonate diagenetic minerals in each stage to obtain absolute ages of the carbonate diagenetic minerals, carrying out cluster isotope testing to obtain formation temperatures of the carbonate diagenetic minerals, and carrying out geochemical analysis to obtain geochemical analysis results of the carbonate diagenetic minerals; acquiring a work area burial history model, and acquiring the burial depth by combining the absolute age of carbonate diagenetic minerals in all stages; on the basis of the absolute age, the formation temperature, the burial depth and the geochemical analysis result of the carbonate diagenetic minerals in each stage, determining the diagenetic environment of the carbonate diagenetic minerals in each stage; and on the basis of the type of the carbonate diagenetic mineral in each stage, the diagenetic environment and the absolute age, establishing a relationship between the type-diagenetic environment of the carbonate diagenetic mineral and the absolute age under an absolute age coordinate system.

Description

technical field [0001] The invention belongs to the technical field of evaluating carbonate rock reservoirs in petroleum and natural gas geological exploration, and in particular relates to a method for restoring the evolution history of carbonate rock diagenetic environment under the absolute age coordinate system based on dating and temperature measuring technology. Background technique [0002] The diagenetic environment includes seawater diagenetic environment (normal seawater and evaporated seawater), atmospheric freshwater diagenetic environment (early supergene and late supergene), and burial diagenetic environment. The pore reforming events of carbonate rocks in the sequence framework all occurred in various diagenetic environments, and the potential for pore reforming in different diagenetic environments is very different. The normal seawater diagenetic environment is dominated by the construction of primary pores, and cementation can fill part of the primary pores....

AI Technical Summary

Problems solved by technology

On the one hand, the identification of the diagenetic environment of diagenetic products is mainly the qualitative judgment of geologists based on the research of regional geological background and diagenetic sequence. Since there is no constraint of age and temperature data, there is great uncertainty. The identification chart established It can only represent the geochemical characteristics of this diagenetic product, and it is difficult to establish a reliable correspondence between the geochemical characteristics and the diagenetic environment

On the other hand, also because there is no age and temperature data constraints, it is impossible to establish the diagenetic environment changes and the occurrence time of pore reforming events under the absolute age coordinate system, which restricts the pore reforming events and pore-forming effects under the control of regional structural geological background understanding, which is very important for reservoir genesis and distribution prediction

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