This study critically reviews the existing models and concludes that focused deep heat and gas from below the permafrost may be the key factor allowing the formation of GECs, while atmospheric heating indirectly triggers their formation by accelerating cryogenic process rates and the formation of new lakes and rivers. GECs appear to be associated with faulting in the area and form where sub-lake or sub-river talik structures meet local thinning of the permafrost.