For its commanding view eastward across the Long Valley caldera, Mammoth Mountain provides the best overview in the area of the landscape created by volcanic activitiy and faulting of the Earth's crust over the past 3 million years. Clearly visible from this vantage point are landforms created by eruptions from the caldera and the Mono-Inyo Craters volcanic chain. These volcanic structures are situated between enormous faults that, on the west formed the eastern escarpment of the Sierra Nevada and on the east formed the western escarpment of the White Mountains with the intervening down-faulted block forming the Chalfant and Owens Valleys.