The tectonically deformed coal with special petrographical features and compli- cared origin developed in South China.

我国南方构造煤发育，具有特殊的煤岩特征和复杂的成因。

youdao

The tectonically deformed coal with special petrographical features and compli- cared origin developed in South China.

我国南方构造煤发育，具有特殊的煤岩特征和复杂的成因。

youdao