Black Pool, West Thumb Geyser Basin
Not long ago, Black Pool was truly black. Lower water temperatures allowed thick mats of dark green and brown thermophiles (heat-loving
microorganisms) to grow in the pool, causing it to appear black. The water temperature rose during the summer of 1991, killing these organisms. Black Pool also erupted that summer and several times the following winter. Black Pool is now one of Yellowstone's most beautiful pools.
- Russ Taylor
- Image Size
- 4016x6016 / 1.2MB
- Contained in galleries