The Storegga Slides and Shelf Failure area 

A detailed sonar-built image of the extent of the shelf collapse and the layered slides comprising the Storegga Slides, underlying the Ormen Lange methane gas extraction field off shore western Norway. Copyright restrictions may apply.

http://www.ngi.no/upload/16282/Raskant-m-Ormen-Lange%20590-442.jpg