塔中Ⅲ区是一个以油藏为主的含油气区，是塔中地区奥陶系碳酸盐岩油气藏的重要产油区之一。研究区内奥陶系主要发育3套优质碳酸盐岩储层、3套区域或直接盖层，为油气成藏提供良好的储集空间和封盖条件；断裂广泛发育，北西向逆冲断层控制油气藏的形成，北东向走滑断层是油气运移的重要通道。塔中Ⅲ区油气具有多层系富集的特征，各层系主控因素不同，油气分布各异：①受沉积相控制，良里塔格组主要发育台缘相控岩性油气藏，沉积相控制储层分布，储层分布控制油气分布，油气主要分布在台地边缘礁滩体和礁后滩上，此外，还发育断控缝—洞型油气藏，在台内呈点状零星分布；②受不整合面控制，一间房组发育不整合型油气藏，不整合面控制储层分布，并与走滑断层共同为油气运移提供重要通道；一间房组油气主要分布在平台区、台垒带和斜坡带的Z10井区，是塔中Ⅲ区最主要的产油层系；③受构造和地层控制，鹰山组主要发育构造岩性油气藏；油气主要分布在平台区构造高部位的有利构造圈闭发育区。

Ⅲ-zone in central Tarim Basin is a petroleum province dominated by oil reservoirs.It is one of the important oil-producing areas with Ordovician carbonate rock reservoirs in central Tarim Basin.Three sets of high quality carbonate rock reservoirs and three sets of regional or direct caprocks are mainly developed in the Ordovician within the area,which provides favorable reservoir space and sealing conditions for hydrocarbon accumulation.Faults are widely developed in the area.The NW-trending thrust faults controlled the formation of hydrocarbon reservoirs,while the NE-trending strike-slip faults became important passages for hydrocarbon migration.The hydrocarbons in Ⅲ-zone of central Tarim Basin have the characteristics of multilayer series enrichment.Various layer series have different main controlling factors and different hydrocarbon distributions.(1)For the control of sedimentary facies,lithological reservoirs that were controlled by plateau-edge facies are mainly developed in Lianggetage Formation.Reservoir distribution was controlled by sedimentary facies,while hydrocarbon distribution was controlled by reservoir distribution.Hydrocarbon is mainly distributed in the platform edge reef flat and back-reef areas.In addition,the fault controlling fracture-hole type reservoirs are also developed,with a spot-shaped distribution in the platform.(2)For the control of a plane of unconformity,unconformity type reservoirs are developed in Yijianfang Formation.The plane of unconformity has controlled reservoir distribution,which provides important passages for hydrocarbon migration along the strike-slip faults.Hydrocarbon of Yijianfang Formation is mainly distributed in the platform,the platform horst zone and well Z10 area of the ramp zone,which are main oil-producing series of Ⅲ-zone in central Tarim Basin.(3)For the control of structures and formation,structural lithological reservoirs are mainly developed in the Yingshan Formation.Hydrocarbons are mainly distributed in areas with favorable structural trap developed in structural highs in the platform.