Volcanism occurred in the area of Lake Suguta when it existed, resulting in the formation of pillow lavas and phreatomagmatic activity, lava flows of Emuruangogolak volcano reached the lake on its southern margin 11,000 - 9,000 years before present, and a layer of tephra was deposited in parts of the lake 8,770 years before present. A number of cinder cones have been modified by Lake Suguta, and the increased availability of water allowed the onset of fumarolic activity at volcanoes today too dry to support fumaroles, such as on The Barrier where fumarole sinter was emplaced when Lake Suguta existed.