CHARACTERISTICS AND CONTROLLING FACTORS OF DOLOMITE RESERVOIR INYUDONGLIANG AREA,SICHUAN BASIN

Based on lithology Characteristics,micro-area and multi-parameter experimental analysis of samples,which were taken from 6 outcrops of Yudongliang area in the north of Sichuan Basin,this paper studied the dolomitereservoir of lower Triassic Feixianguan Formation. Grain-dissolved dolomite reservoir is the optimum. The controllingfactors are summed up as follows: shallow facies of platform margin or platform inner is the environmentbasement of reservoir;the type of grains is the material basement;penecontemporaneous dissolution by fresh wateris the key to the formation of reservoir;earlier proper dolomization preserves the reservoir;later acid fluid are importantfactors that the reservoir improves;both earlier and later excessive autogeny dolomite would fill the poreswhich is one kind of disadvantage for the reservoir.