A volcanic fumarole on Hot Creek in the Long Valley Caldera, Owens Valley, California, 1982. A volcanic fumarole boils violently just at water's edge to the creek. Some pools are cool enough to bathe in, others such as this one are good for instant boiled eggs. Such features?demonstrate the continuing volcanic activity giving Hot Creek it's name.??Long Valley Caldera is adjacent to Mammoth Mountain, scene of frequent earthquakes. The valley is one of the largest calderas on earth, measuring a