Bases on thevarious floor the author has studied detailly the water inrush mechanism of Ordovicianlimestone.That is floor failure water inrush, fault water inrush, and canny water inrush.

• 针对不同的底板情况，详细研究了奥灰含水层的突水机理，提出三种奥灰突水类型，即底板破坏型，断层型和裂隙型突水。