Abstract: Gas hydrates are widely distributed in the world, mainly in the oceans and permafrost regions, and closely related with the geological and structural environment. Now, these gas hydrates deposits that have been found are mainly identified by BSR. The methane origin in gas hydrates includes biogenic, pyrolysis gas genetic and inorganic gases. The gas hydrates accumulation and mechanism explored by most researchers is mainly based on the genesis of methane gas. This paper analyzes the controlling factors of forming gas hydrates, including the gas source, deposition conditions, geological structural conditions, temperature and pressure conditions, etc. It is these that control the existing state, formation mechanism and scale of gas hydrates deposits. Also, this paper analyzes the favorable conditions of gas hydrate accumulation in the Gulf of Mexico for the purpose of being taken as a reference for China's gas hydrate exploration.

Key words: natural gas hydrate, accumulation mechanism, favorable conditions, scale