 On the other hand, processes that are associated with eruption, transportation and deposition are notably different because of the presence of water.Such differences that the presence of water entails is the ability to vaporize when in contact with water, a high density and resulting confining pressure, high viscosity relative to air and differences in the thermal conductivities/heat capacities in the air relative to water.Some understanding of subaqueous volcanoes can be inferred from knowledge of volcanic processes based on ancient successions.