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Natural gas hydrates are solids formed by the combination of water and gases, which may be hydrocarbons or not. It has the appearance of snow or dry ice and crystallizes in the form of nodules, layers or within faults and in the porous space of marine sediments. They are distributed along the continental margins around the world or in permafrost zones, located in the polar circles. Hydrates originate through the movement of gaseous molecules during migration within the sedimentary column or in the water, through an exothermic reaction that freezes the water immediately surrounding each gas molecule. This molecule, usually methane, is then trapped within a crystalline structure composed of a trap of water molecules. For this reason, hydrates are also known as methane clathrates. However, other natural components such as ethane, propane and carbon dioxide can be observed in this form. The maximum temperature for this structure to be stable depends on the combination of temperature and pressure in the gas hydrate stability zone and, secondarily, on the composition of the gas and the salinity of the water contained in the pores of marine sediment. Methane, trapped as a hydrate, may be biogenic or thermogenic. Experimental studies indicate that 1 m3 of methane hydrate, dissociated under pressure and atmospheric temperature, releases 164 m3 of natural methane, in addition to 0.8 m3 of fresh water. For this reason, estimates of the amount of natural gas contained in hydrates far exceed the known reserves of natural gas in the world, ranging from 105 trillion cubic feet (TCF) to more than 3x109 TCF. The volume of carbon contained in this form is estimated to be twice the total amount of all the earth's fossil organic carbon, including oil, gas, and coal. Gas hydrates have been attracting interest as a potential energy resource, in addition to being considered as a possible cause of greenhouse effect and of instability of marine slopes. However, little is known about the factors controlling the formation and stability of hydrates on the marine seafloor, although significant advances have been achieved thanks to the continued study of the subject by academies and research institutions. The interaction between gas hydrates dissociation and methane plumes at the seawater column is a natural phenomenon that modifies seafloor scenario, transforming the landscape by the precipitation of carbonates and pyrite on the shallow sedimentary pores, resulting in nucleous of hardgrounds for living benthic organisms, known as chemosynthetic communities. For this reason, methane seeps related with gas hydrates dissociation creates a micro environment for living species, important for the marine ecosystem. This is an open and exciting study field for geologists, geochemical researchers and biologists.