Fly Geyser spouts fountains of boiling water into the backlight of the morning sun in the Black Rock Desert of Nevada. But the almost unreal beauty of the geyser is ephemeral. Its appearance changes continuously. Such seemingly extraterrestrial landscapes are rare on Earth today. The seething breath of the Earth may offer a glimpse of what our planet might have looked like in its early days.
Unlike the geyser cones in Yellowstone, which fall dry between eruptions, Fly Geyser is the only geyser of its kind that continuously discharges boiling water from three vents heated by an active magma chamber at shallow depth. Heat-resistant bacteria thrive on nutrients in the hot water. The red zonation results from thermophilic bacteria that thrive in water at 80°C (176°F), while the yellow and green areas of the geyser are home to different bacterial species that successively tolerate water temperatures down to 50°C (122°F).
The geyser is located in the Black Rock Desert in the middle of a huge dried-up lake that covered 22,000 km² (8,500 mi²) at the end of the last ice age. Basaltic lava forms the bedrock beneath the sediments of the former lake. The corresponding lava eruptions occurred during the ice age. The magma chamber is still active and supplies the groundwater system feeding Fly Geyser with heat.
Although the appearance of this landscape has changed many times during the last 10,000 years, it may be more exceptional and beautiful today than ever before.
