A metán-hidrát és a só kapcsolata az Erdélyi-medence gázainak képződésében
The relation of methane hydrates and salt in the generation of the gases from the Transylvanian Basin
Keywords:
dissociation of methane hydrate, dilution of formation water, /, metán-hidrát disszociáció, rétegvizek kiédesedéseAbstract
Our results suggest that all conditions supporting the formation of methane hydrate exist in the Miocene Transylvanian Basin. The methane, generated from the primary (biodegradation) and the secondary sources, was trapped in water clathrates, creating multiple Miocene methane hydrate horizons preserved for millions of years until the Eastern Carpathian magmatic activity started, when the regional geothermal gradient increased, and the methane hydrate consequently dissociated. This yielded free methane, which escaped from the H2O molecule clathrate cages, and is considered herein the tertiary methane source in the Transylvanian Basin. The idea is supported by the chlorinity anomaly (7-12 g/L) of the formation waters of several gas fields.
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