OUTBURST OF COAL AS A CONDITION OF SELF-ORGANIZED CRITICALITY
The results of the study of the composition of particulate samples of Donbass coal petrographic method are given. It was found that the particle size distribution is described by a power law or lognormal. Both distributions correspond to the scale independent process of crushing coal, dependent on the conditions of deformation and show the fractal microstructure of coals. The calculation of the fractal dimension (box-counting method) in the program JmageJ was done. According to the study, the fractal dimension D for undisturbed coal varies between 1.827... 1.874, for selected areas of release and violation is the same and equal to 1.757, and for the undisturbed coal, but from the zone violation (occupies a middle position between disturbed and undisturbed coal) is 1.820. Values of the fractal dimension for undisturbed coal and coal taken from disturbed and outburst zones are essentially different at the micro level. The power law distribution of the particle size of the disturbed coal outburst zones and allows us to consider their state as a state of self-organized criticality (SOC).