本文提出了宜昌奥陶系沉积相是台地相—台地边缘相—浅海盆地相的多相台棚式的组合类型，指出奥陶系经历了四次海进到海退的沉积旋回过程。

In this paper, it is suggested that the Ordovician sedimentary facies in the Yichang region are a combination type consisting of platform facies, platform margin facies and shallow sea basin facies.

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