DETONATION OF HEAVY HYDROCARBONS IN MANTLE FLOWS

A quantitative thermodynamic model for detonation of metastable accumu lations of heavy hydrocarbons ascending from the upper mantle is consi dered. The Chapman-Jouguet detonation parameters were determined by mi nimizing the minus-entropy of the C-H system of composition 1:2.1 with a fixed internal energy under isochoric conditions by means of the pr ogram complex Selektor-C. It has been established that the energetic c apacity of metastable heavy hydrocarbons (MHH) is close to that of tri nitrotoluene. It varies in the depth range of 30-90 km and is maximum at a depth of 62 km. The maxima of excessive pressure and temperature resulted from MHW detonation also lie in this range. Depending on the regime of MHH ascension - isothermal or nonisothermal (by a geobarothe rm) - and the depth from which a fluid ascends to a detonation focus, at the detonation instant the pressure can reach 210 kbar and the temp erature attains 4800 degrees C. Estimates are given for the radii of b all-shaped MHH accumulations, whose detonation may be accompanied by e arthquakes with release of energy of 10(18)-10(22) erg.