关键词: 塔里木盆地, 塔河油田, 奥陶系, 碳酸盐岩, 岩溶, 油气勘探方向

Abstract: Oil and gas discovery in Yijianfang Formation of Lower Ordovician in Tahe Oilfield since 2001 proved the prediction about existence of like-layered reservoir in this area.The existence of like-layered reservoir of well-developed karstification caused by surface water and deep water during Caledonian orogeny as well as the affection of surface karst and deep karst on reservoir accumulation may be favorable for establishing and developing the idea that we would pay equal attention to both of network reservoir and like-layered reservoir.It would have been launched out the exploration of carbonate oil and gas reservoirs in Tarim Basin,based on the concept of "large karst" including multi-stages surface and deep karsts formed during the reservoir-forming and "large uplift",which might mean all paleo-uplifts above the erosion base level in the strongest erosion stage and their evolution process.

Key words: Tarim Basin, Tahe Oilfield, Ordovican, carbonate rock, karst, oil and gas exploration