Nature Gas Reserve-forming Condition And Reserve Computing In North Of Tangyuan Rift

Stratigraphical classification and correlation have been done again by the theory of sequence of stratigraphy. With the previous study result of tectonic and source rock, nature gas generating conditions such as sedimentary features , physical properties of reservoir and so on have been researched. Jixiangtun and Hulicun of more favorite zone have been made detail geological analysis, calculated nature gas proved reserves of Jingxiangtun area. By stratigraphical classification and correlation, now discovered gas generation layers are all developed in sequence strata â…¡. Sequence â…¡i s single lake contract systems tracts, composed of two progressive parasequence sets thicker upper. Lithological properties are primary interbed of ashen middle or fine-grain sandstone and ashen or black mud-stone. Gas beddings develop in the sandstone reservoirs of top of parasequence sets. Sandstone reservoirs hold gas are mainly fan-delta under-water channel sand-body. In the region ,fan-delta has properties such as near provenance ,short river ,steep slope, well developed grand channel. The sand-body of reservoirs is high heterogeneity and low lateral correlation tracing property. Faulting plays an important part in the evolution, deposition, gas-pool generation and reservation of northern of Tangyuan rift. In the region faulting structures are complex, movement stage of fault is much, difference of interval is big, fractures in different stage set the region broken, as the result, the gas-pools reserved are odd and complex. Condition of source rock ,reservoir and seal bedding have been studied detailed with Jixiangtun and Huzhucun area, determined type and parameters of gas-pool in Jixiangtun and Huzhucun area, calculated the proved reserve and dynamic recoverable reserve of gas-pool, and proved the reserves by different methods.