Understanding & Investigation of Affected Factors on

Consumption of conventional gas reservoirs and development of drilling, logging and coring technology, many countries and scientists have focused on the gas hydrate explorations. Recently many successful gas hydrate wells have been drilled in the world which is often on the marine environment. Almost one decade ago, it was considered that drilling in gas hydrate reservoirs was quite risky. However, recent drilling expeditions in marine environment show that gas hydrate does not risky and big oil services companies encourages to development of these drillings. Because successful drilling results withdrawals from gas hydrate reservoirs does not dissociate immediately and consequently lot of considered theoretical problems ruled out of the drilling of these reservoirs. It is obvious that special cares should be taken to maintain gas hydrate reservoirs as stable as possible with drilling fluid selection and cement composition selection. This paper presents a comprehensive perspective on the results of drilling activities in the gas hydrate reservoirs.