The water - inrush possibility during mining depth coal layer is assessed.

评价了肥城煤田深部开采底板突水的可能性。

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In the stone coal layer and the overlying black shale, there is a pyrite layer.

在石煤层或其上部的碳质页岩中含黄铁矿层。

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Therefore, it is necessary to accurately know the position of coal layer and its parameters.

因此，准确地掌握煤层位置和有关参数是十分必要的。

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