Drumlin Formation By Catastrophic Flooding Since 1983, several investigators have developed a theory of drumlin formation by catastrophic flooding due to the release of meltwater that is believed to have accumulated beneath melting ice sheets. The proposed catastrophic sheet floods, as wide as the drumlin fields, formed the drumlins and related streamlined landforms, such as flutings, over wide areas. So-called rogen moraine, consisting of transverse ridges of drift, often found associated with drumlins, is reinterpreted in the meltwater flood hypothesis as possible giant current ripples. Existing drumlin fields reveal the exten