INFLUENCE OF GAS HYDRATE FORMATION ON METHANE SEEPS AT THE BOTTOM OF WATER RESERVOIRS
A.Kh. Degterev
Ordzhonikidze Russian State Geological-Prospecting University, ul. Miklukho-Maklaya 23, Moscow, 117997, Russia
Keywords: Bottom gas seeps, methane bubbles, gas hydrate particles, numerical modeling
Subsection: GEOPHYSICS
Abstract
It is shown by numerical modeling that the height of gas flares above underwater methane seeps depends strongly on water parameters. A simulation model of the dynamics of a rising bubble was used. Along with gas exchange through the bubble wall, the model takes into account gas hydrate formation, whose rate is determined by turbulent heat exchange with water. Calculations were performed for depths of 250 to 1500 m with an initial bubble diameter of 0.2 to 1.5 cm. It is shown that at the water temperature of the Arctic seas, rising methane bubbles transform into gas hydrate ice within the first 1-2 m of their path. At the same time, when the water temperature is higher than the hydrate formation temperature near the sea bottom or close to it, the bubbles travel a distance of tens or hundreds of meters before complete dissolution or complete hydration.
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