Pore pressure evolution and gas hydrate accumulation duruing sequental deposition of sediments with different hydrodynamic and rheological properties
Category: 15-1
UDC 550.31
E.I. Suetnova
Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia
Abstract
Peculiarity of the evolution of gas hydrate accumulation in ocean floor was investigated by numerical modeling for the case of sequential deposition of sediment material having different permeability and effective viscosity. Model calculations show that the decrease of viscosity and permeability of sediments which precipitates on to sea floor after certain time essentially increases the rate of gas hydrate accumulation from dissolved gas, pore fluid velocity and pore pressure. The value of such an increase depends nonlinearly on decreasing of permeability and effective viscosity and time. Calculations show that hydrate saturation and pore pressure depend on hydrodynamic and rheological properties of current sediments as well as their values in the past.
Keywords: sedimentation, gas hydrate, compaction, rheology, numerical modeling.
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