DIAGENESIS AND DIAGENETIC FACIES OF DONGHE SANDSTONE OF AKEKULE UPLIFTIN TARIM BASIN

On the basis of core analysis,casted thin section,scan electron microscope,electron probe and X-raydiffraction,this paper studies the diagenesis and diagenetic facies of Donghe sandstone of Akekule Uplift,TarimBasin.The reservoir rocks mainly include Quartzarenite,Sublitharenite and less Litharenite,subarkose,feldspathiclitharenite.The types of the diagenesis are the compaction,cementation,replacement and dissolution.Theconstructive diageneses mainly included compaction,cementation,replacement.and the constructive diagenesesare disolution.Later Carbonate cementation was the most unfavorable destructive diageneses.The diagenetic stagebelongs to theAmiddle diagenesis.Four diagenetic facies were petrographically and petrophysically recognized.They are later carbonate cementation dense diagenetic facies,weak Quartz cementation and strong dissolution diageneticfacies,strong Quartz cementation and weak dissolution diagenetic facies,relatively strong compactiondiagenetic facies.The weak Quartz cementation and strong dissolution diagenetic facies were favorable for formingand keeping secondary porosity.