Severe damage from super-heated flows of gas, ash and pulverized rock (pyroclastic flows and surges) may occur at least from an explosive eruption.: The amount of damage depends on vent location, topography, and volume of magma erupted. Pyroclastic flows from vents on Mammoth Mountain or other high vent could travel farther by gaining extra momentum from their descent. Valleys along the route will be more impacted than ridges but flows and surges could overtop some ridges. Eruptions near snowpacks may produce lahars of mud and ash that devastate valleys and watersheds. Steam blast eruptions under a lake could form large waves capable of flooding nearby areas and starting mudflows.: