关键词: 江陵凹陷, 深储层, 次生孔隙, 储层非均质性, 硬石膏胶结物, 长石溶解

Abstract: The reservoirs developing secondary pores over 3000 meters in depth of Jiangling Depression during the late Cretaceous period were found in recent years.The secondary pores mainly resulted from cement dissolution have serious heterogeneity and control the formation of effective oil reservoirs.As pH value varied in the course of diagenesis,reservoirs experienced one to three cementations or dissolution generations.Lots of secondary dissolution pores developed in the late diagenetic stage,because of the acidic mediums in the process of generation and migration of oil and gas.The anhydrites deposited in the dissolved pores resulted in the heterogeneity of secondary pores.The contents of anhydrites cements closely connected with that of the feldspar in reservoir rock.The content of anhydrites cements in quartzose sandstone is low,and the content of that in felspathic sandstone is high.The main cause of such phenomena is that feldspar solution provided sources for the deposition of anhydrites in dissolved pores.

Key words: Jiangling Depression, deep reservoir, secondary pores, reservoir heterogeneity, anhydrite cements, feldspar solution