The dark shale is broadly forming in all the area of the slope and the deep depression.

暗色泥质岩在全区的深坳陷和斜坡均有发育。

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The dark shale is broadly forming in all the area of the slope and the deep depression.

暗色泥质岩在全区的深坳陷和斜坡均有发育。

youdao