In sub-project A3 an innovative new 3-D module for modeling the formation of basin-wide gas hydrate accumulations has been implemented into the commercial software package PetroMod of Schlumberger AaTC. This unique model will now be calibrated and refined with available data sets from different permafrost and marine gas hydrate deposits (e.g., Alaska North Slope, Gulf of Mexico). Thus, PetroMod now combines its leading art of petroleum system modeling with microbial POC degradation kinetics to predict gas hydrate formation and stability over the geological history of a basin. A3 simulations are complementary to the reservoir modeling in B1.