CHARACTERISTICS OF SEDIMENTARY DIAGENESIS FOR RESERVOIR ROCKS OF VOLCANIC CONGLOMERATES IN URHO FORMATION AND RELATIONSHIP WITH HYDROCARBON ACCUMULATION

With the discussion on the characteristics of sedimentary diagenesis for conglomerates of peidmont diluvial fan facies on the dry basin margin, the inner relations of the resolution, solution and porosity evolution of authi-genic zeolites with hydrocarbon accumulation in sandstone enriched in volcanic elastics with poor minerals and low textural maturities were explained. The author related the reservoirs for oil fields with conglomeratic rocks in Urho system to minor fissure-pore type (secondary pores). Authigenic zeolites are index minerals for the growing band of secondary pores. In the direction of stream line of palaeo-river channel on the fan waist and the sector, and in the updip of source rocks along Karamay-Urho rift, there are conglomeratic bodies within which good collocation of lithological assemblage of cap-reservoir-trap and ideal structural deposition were formed, which are favou-rable for the formation of commercial oil and gas pools.