Abstract:

Multidisciplinary analyses of reservoir geology and exploitation geology reveal that the Ordovician carbonate reservoirs in Tarim Basin are differentwith conventional reservoirs.They feature in extensiveness of oil/gas distribution，diversity of oil/gas property，layering and heterogeneity ofhydrocarbon accumulation，and instability of oil/gas production.There are two basic geological conditions controlling the formation of these special reservoirs，namely great reservoirheterogeneity andmultiˉphase hydrocarbon accumulation and latemodification.The special carbonate reservoirs thathave large oil/gas-bearing area，complex oil/gas-water contacts and a small amount ofwellswith high and stable production contributing to bulk of the oil/gas production are common in the Ordovician carbonates in Tarim Basin.Therefore，an integrated exploration and development strategy should be employed.

Key words: carbonate rock, Ordovician, oil/gas reservoir, exploration and development, Tarim Basin