The problem of rock pre-fracture under quasi-static and di-namic loading is considered. It is shown that under dynamic loading it is possible to form pre-fracture zones of large extent. The data of ultrasonic measurements after non-destructive explosive loading are presented. Experimental data on changes in the velocities of elastic wave propagation after dynamic loading are presented.

At present, when a number of industrial regions producing coal are experiencing a shortage of gas fuel, the problem of industrial production of methane at coal deposits is urgent. To solve it, it is necessary to investigate a number of fundamental scientific problems. One of the main tasks is to establish the patterns of decay of the natural system "coal - methane" and the migration of methane to mining wells. According to the views prevailing among many experts, almost all of the methane is in the coal in the absorbed (dissolved) state, and the coal bed is initially gas-tight. Therefore, not in all cases, drilled wells can give methane in the required volume. This is evidenced by field experiments. Some gas production wells produce little methane. Other wells, such as those in the coal fields of the San Juan Basin, have very high gas yields.