THE RESERVOIR ANALYSIS OF M5(4)(1) MEMBER OF LOWER PALAEOZOIC IN THE SOUTHERN AREA OF SULIGE GAS FIELD, ORDOS BASIN

The M5(4)(1) member of lower Palaeozoic is one of the major gas producing layers in the southern Sulige gas field. The research on the analysis of M5(4)(1) reservoir are investigated by using data such as core, physical property analysis, gas and water distribution law. The results have shown that: (1) the average effective porosity and permeability of M5(4)(1) reservoir of the southern area of Sulige gas field is respectively 4.3% and 1.5mD, showing that the study area is low porosity and low permeability gas reservoir. (2) the main pore type of reservoir is dolomite dissolution pore and secondary pores such as anhydrite-moldic pores. (3) the northern region of study area is the detained water at low position of the structure and gas-water in the same layer, the southern region shows the characteristic of gas-water in the same layer. (4) the undercompaction of M5(4)(1) reservoir is not developed. The research results will provide a theoretical basis for improving the development effect of gas reservoirs in this area.