Gas hydrate potential of the Sea of Marmara

Abstract

In this study, the gas hydrate potential of the Sea of Marmara was analyzed in detail in terms of energy resource potential and environmental geohazards. Initially, GHSZ thickness maps for different gas compositions in the Sea of Marmara were drawn according to the estimations made by using HEP simulator and an algorithm developed in this study. Pure/nearly pure CH4 hydrate is not stable in the conditions of the Sea of Marmara, but thermogenic gas hydrates were recovered in the Sea of Marmara. It was shown that when C3H8, CO2, and H2S concentration in gas compositions increases, the thickness of GHSZ also increases. For the best scenario, GHSZ thickness is nearly 287.2 m below the seafloor. Technically recoverable natural gas hydrate potential in the Sea of Marmara is up to 125.8 bcm (billion cubic meters). In this study, it was proposed that the importance of gas hydrates in the Sea of Marmara is higher in terms of environmental perspectives rather than its energy resource potential. Up to 1820.2 bcm of natural gas might be stored in sII gas hydrates of the Sea of Marmara. In terms of environmental perspectives, free gas sections in the bottom of gas hydrates at the bottom boundary of GHSZ are risky because the possible connection of the free gas section with the seafloor due to tectonic activities might cause catastrophic results for the environment. Overall, gas seeps through the atmosphere are possible in the Sea of Marmara, where is crossed lengthwise by the Northern branch of the North Anatolian Fault (NAF).