Abstract:

There are many types of CO₂ reservoirs, and the diversities of reservoir forming are identified in Jiyang depression, Shandong. The genesis of CO₂ reservoirs was analyzed by component content and isotope analysis of CO₂ reservoirs. The result shows that mantleresource gas is the key genesis, and the magma gas source body is the most important source of the CO₂. The volcanic body, volcanic conduit and the breaking near the magma gas source body played an important role in CO₂ migration and reservoir forming. The processing of CO₂ migration and reservoir forming were analyzed by a set of modeling experiments, such as CO₂ migration under pressure release, in fissure, in porosity-fissure and in sand deposits, and combined with the given migration and forming processing to construct three reservoir-forming modes, which are intrusion-breaking-reservoir dogleg, direct intrusionreservoir forming and direct buried volcanic conduit-reservoir forming. It lays a foundation for researching the CO₂ reservoir-forming and integrated exploration in Jiyang depression.

Key words: Jiyang depression, CO₂, gas source body, volcanic conduit, geologic reservoir-forming processing, reservoir-forming mode