Existing comment:
West Thumb Geyser Basin:
An Exploded Bay:
West Thumb's shoreline has suspiciously crater-like contours. Its underwater profile is dramatically deeper than the rest of Yellowstone Lake. Only a massive explosion could have formed West Thumb.
Though the blowout occurred 125,000 years ago, West Thumb is still thermally active. Hot springs, mudpots, and geysers steam and percolate along the shore, and temperature gauges record high heat flow in lake bottom sediments. |