Tree kill:
This is an aerial view showing the large extent of the tree kill area on the slopes of Mammoth Mountain. Carbon dioxide (CO2) is heavier than air and will pool in depressions and caves. Recent measurements at Mammoth Mountain indicate that the total rate of carbon dioxide gas emission is close to 300 tons per day. The most likely sources of the carbon dioxide are degassing of near surface magma and gas release from limestone-rich rocks that are heated by nearby magma.