Explosive processes in the permafrost zone as a new type of geocryological hazard

Abstract

The natural and human-induced explosive processes in the permafrost area were studied. A new approach is proposed to the theory of formation of gas emission funnels. It is based on the mechanism of migration of gas fluids from the gas hydrates dissociation zone to the overlying permafrost. The dissociation zone is formed in the areas of local heating due to the heat input from above. The preparation stages of the explosive process that formed the Yamal crater are shown. The preparation phases of natural explosive processes have been identified and characterized. Different scenarios are considered for the preparation of natural explosive processes in the cryolithozone. The main conclusions of the conducted research are the following: the explosions of hydrolaccoliths and the formation of gas emission funnels belong to one group of processes, i.e., physical explosions of natural origin; preparation of explosive processes in the permafrost goes through several stages; the migration of gas fluids plays an important role in the preparation of natural explosions in the permafrost. With the ongoing economic development of the Arctic, thermal effects on permafrost increase, and so does the hazard of explosive processes for engineering structures. However, this group of processes is not taken into account when choosing design solutions and predicting the interaction of an engineering structure with permafrost soils; moreover, these processes are even not included in the group of hazardous geological processes.