Characteristics Of T3x3 Tight Gas Reservoir,Jiange-Yuanba Area

JianGe-YuanBa area in the third member of Xujiahe Formationis is a set of poor reservoir matrix property, strong heterogeneity, high density and complex gas reservoir of sand shale interbed, currently in the early stages of the exploration. In this paper, on the basis of core, make full use of drilling core, scanning electron microscopy(sem), the casting thin sections, well logging, mud logging, testing and laboratory analysis data, according to the sedimentary characteristics,sand body distribution, reservoir characteristics, diagenesis and the densification process of the study area was studied, finally analyzed the influence factors of reservoir development in the studied area. Studies suggest that JianGe- YuanBa region belongs to fan delta-lake sedimentary environment,the main sedimentary development of the fan delta front subfacies, coastal and shallow lake facies, favorable sedimentary microfacies is an underwater distributary channel microfacies, debouch bar microfacies and part of the sheet sand microfacies; Sandstone type of research area mainly is fine-meaograin calcarenaceous sandstone, followed by lithic quartz sandstone, and a small amount of feldspathic lithic sandstone, The main diagenesis types is compaction, dissolution and cementation effect; the diagenesis stage of purpose layers have been middle diagenetic B stage; Reservoir is the densification time J3sn(suining group) late sedimentary; Affect the control factors of the reservoir mainly include tectonism, sedimentation and diagenesis, the main development of the reservoir sedimentation macro distribution, dissolution as a constructive diagenesis is secondary pore zone appeared in the region, one of the main function of compaction, cementation, as destructive diagenesis. And structure function as a large area through greatly improve the reservoir permeability and oil and gas production, is the important condition of reservoir and high yield.