塔里木盆地古生代海相碳酸盐岩储集岩特征

通过对塔里木盆地古生代碳酸盐岩储集岩的勘探和研究,较系统地阐述了储集岩类型、储集空间类型、储集性能以及碳酸盐岩成岩作用等,并进行了评价。塔里木盆地古生代碳酸盐岩储集岩类型主要有古岩溶风化壳型、礁滩型、鲕粒滩型及白云岩型4类。5期构造运动形成了5期古岩溶储集体,即下寒武统—上震旦统、中奥陶统—上奥陶统、志留系—奥陶系、石炭系与下伏地层、三叠系—前三叠系之间的古岩溶。碳酸盐岩储集空间类型主要分为孔隙—孔洞和裂缝2大类型。孔隙-孔洞包括微孔隙、晶间孔隙、溶蚀孔隙和溶蚀孔洞;裂缝主要有成岩裂缝、与区域构造有关的裂缝、与褶皱有关的裂缝、与断裂有关的裂缝、与深部地层负荷和孔隙压力有关的裂缝等。碳酸盐岩储层主要成岩作用有压实、压溶、胶结、白云化、重结晶、硅化和溶蚀等。储集岩主要有白云岩和灰岩2大类,白云岩以裂缝-孔洞型为主,而灰岩主要为裂缝型,仅有少量孔洞-裂缝型及裂缝-溶洞型,因此白云岩储层的储集性能明显好于灰岩。 

RESERVOIR ROCK CHARACTERISTICS OF PALEOZOIC MARINE FACIES CARBONATE ROCK IN THE TARIM BASIN

Based on study of Paleozoic carbonate reservoir rock in the Tarim Basin,it is discussed in this paper reservoir rock type,reservoir room type,reservoir capacity and carbonate rock diagenesis.Paleozoic carbonate reservoir rock in the Tarim Basin can be classified into 4 types: ancient karst and weathered residuum,shoal and reef,oolitic beach and dolomite.5 stages of tectonic evolution result in 5 stages of ancient karst reservoir,including: Lower Cambrian-Upper Sinian,Middle Ordovician-Upper Ordovician,Silurian-Ordovician,Carboniferous and underlying strata,and ancient karst between Triassic and Pretriassic.Reservoir room is divided into 2 types: pore-vug and fracture.Pore and vug include micropore,intercrystalline pore,dissolution pore and dissolution vug.Fractures include diagenetic fracture,facture related to regional tectonics,fracture related to fold,fracture related to rupture,and fracture related to deep strata charge and pore pressure.Diageneses of carbonate reservoir rock include compaction,pressure solution,cementation,dolomitization,recrystallization,silicification and dissolution.Reservoir rocks include dolomite(fracture-vug type) and limestone(fracture type,with few vug-fracture type and fracture-carven type).Reservoir capacity of dolomite is much better than that of limestone.