This paper discusses some important problems in block caving，such as：the cavingmechanism of the ore，the caving law of the ore body，the evaluation and classification of thecavibility，ore fragment prediction and measurement，engineering control method in blockcaving，and so on.

This paper summarizes the laws of decline in many large-scale private enterprises,especially analyzes the external agencies of the declined enterprises,and advances the corre- sponding countermeasures.

Sequence stratigraphy and coal-forming laws in Pingzhuang basin of Inner Mongolia;

Study on iate paleozoic coal-forming law in eastern henan;