Abstract: By using the high pressure gas gun as power to accelerate plane plate, and the amphibole samples, which were subjected to the plane plate impacted with different impulses, have been recovered. Then these recovered amphibole samples have been studied by some micro-mine research techniques such as SEM, XRD and RAM. In this research, the stress intensity in the beginning phase of crack appearing and the extending shape of cracks have been confirmed. Based on the analyses of micro-examination for these recovered samples, the formation principle of crack is expounded and proved there is phase transition in the amphibole. These experimental results can provide a kind of new theoretic basis for the further studying of the explosion in mine exploitation, architecture engineering, etc.

Key words: dynamic high-pressure, rock, fracture mechanism, phase transition