Yellowstone NP

Visitors can follow paths around many of the geysers and hot springs. Imagine the reaction of the Indians and early explorers to this mysterious region of spouting steam and water! Everyone's favorite - bears. But don't get out of your car to observe them.

Trees killed in 1952 by the emergence of New Highland Spring are now being buried in travertine. Castle Geyser, like Old Faithful, is located within the Upper Geyser Basain. It is one of the largest geysers in the park. Visitors to the park may see elk . . . Tower Falls drops over the edge of a hanging valley carved in basalt.

Fumaroles are smaller features that emit steam and other gases, sometimes with a continuous roaring sound. The most spectacular of the thermal features are the geysers of Yellowstone. Yellowstone contains > 60% of the world's geysers - springs that spout hot water and steam at regular or irregular intervals. The source of these eruptions, and of the heat which drives geysers, is a hot spot beneath the earth's crust at Yellowstone.

This large hot spring is located at the West Thumb of Yellowstone Lake. Here a steaming hot spring lies in front of an erupting geyser. Much of the Canyon is visible from Inspiration Point.

Most of the volcanic rocks here are rhyolite, an extrusive igneous rock rich in silica. Rhyolite is usually tan or gray, like these lava flows near Tower Falls on the Yellowstone River. Algae growing in the hot water stripes the travertine in orange, brown and yellow. Walk through the terraces to appreciate the extent of Mammoth Hot Springs - almost a square mile in area! The most remarkable of the springs is Mammoth Hot Springs in the northwestern part of the park (not within a geyser basin).

Relief map of Yellowstone This extensive canyon includes 3 waterfalls and many scenic views. A geyser eruption starts small, then builds up to a maximum. A geyser eruption starts small, then builds up to a maximum.

Brilliant colors result from algae. Different levels form when varying amounts of water emerge from the springs. The hot mineralized water can kill nearby vegetation. moose (yes, there is one in this picture!) . . .

Moraines built by Pleistocene glaciers line many of the valleys of Yellowstone NP. Algae or particular minerals may tint the mud various colors, as in the Fountain Paint Pots of the Lower Geyser Basin. Mud pots are hot springs of boiling mud. Bubbles rise through the viscous liquid, then pop, leaving rings on the surface. Springs and geysers in Norris Basin are hotter than any others in the park. This suggests that magma is nearest to the surface in that area.

Welcome to Yellowstone NP, home of Old Faithful. Old Faithful erupts to a height of about 150 feet every hour or so, although the time between eruptions has increased since recent earthquakes in the area. Eruptions have buried many forests in the Yellowstone area over the years. Then the wood may be replaced by silica from groundwater, producing petrified trees. Most of the volcanic rocks here are rhyolite, an extrusive igneous rock rich in silica. Rhyolite is usually tan or gray, like these lava flows near Tower Falls on the Yellowstone River.

Tower Falls drops over the edge of a hanging valley carved in basalt. The Upper Falls drops over a resistant ledge of rhyolite. The Lower Falls drops over a resistant ledge of rhyolite. This view across Hayden Valley shows Mount Washburn, one of the high summits that stood above the ice.

The sun sets over Yellowstone. The mound of Castle Geyser is composed of geyserite, or siliceous sinter - a form of silica similar to opal. In places, it is possible to peer through clear water into the depths of a hot spring. Here, hot water rises through soluble limestone, bringing up > 2 tons of calcium carbonate per day! When the water reaches the surface and cools, a dense form of limestone called travertine precipitates in multi-level terraces.

In 1988, the Yellowstone region experienced devastating forest fires that even threatened historic buildings around Old Faithful. Decades of fire control had allowed dead wood to pile up on the forest floor, where it fueled huge blazes. In the aftermath, park rangers monitor the rejuvenation of the burned areas and reconsider fire control policies. Upstream from Tower Falls lies theGrand Canyon of the Yellowstone. Successive eruptions have produced over 3500 cubic kilometers of volcanic material. When this was removed from underground, the overlying rocks collapsed to form a caldera measuring 30 miles by 40 miles. The lowest part of the caldera is occupied by Yellowstone Lake. The Yellowstone River flows placidly from Yellowstone Lake northward toward its Grand Canyon.

This page created on a Macintosh using PhotoPage by John A. Vink.


Visitors can follow paths around many of the geysers and hot springs.	Imagine the reaction of the Indians and early explorers to this mysterious region of spouting steam and water!	Everyone's favorite - bears. But don't get out of your car to observe them.

Trees killed in 1952 by the emergence of New Highland Spring are now being buried in travertine.	Castle Geyser, like Old Faithful, is located within the Upper Geyser Basain. It is one of the largest geysers in the park.	Visitors to the park may see elk . . .	Tower Falls drops over the edge of a hanging valley carved in basalt.

Fumaroles are smaller features that emit steam and other gases, sometimes with a continuous roaring sound.	The most spectacular of the thermal features are the geysers of Yellowstone.	Yellowstone contains > 60% of the world's geysers - springs that spout hot water and steam at regular or irregular intervals.	The source of these eruptions, and of the heat which drives geysers, is a hot spot beneath the earth's crust at Yellowstone.

This large hot spring is located at the West Thumb of Yellowstone Lake.	Here a steaming hot spring lies in front of an erupting geyser.	Much of the Canyon is visible from Inspiration Point.

Most of the volcanic rocks here are rhyolite, an extrusive igneous rock rich in silica. Rhyolite is usually tan or gray, like these lava flows near Tower Falls on the Yellowstone River.	Algae growing in the hot water stripes the travertine in orange, brown and yellow.	Walk through the terraces to appreciate the extent of Mammoth Hot Springs - almost a square mile in area!	The most remarkable of the springs is Mammoth Hot Springs in the northwestern part of the park (not within a geyser basin).

Relief map of Yellowstone	This extensive canyon includes 3 waterfalls and many scenic views.	A geyser eruption starts small, then builds up to a maximum.	A geyser eruption starts small, then builds up to a maximum.

Brilliant colors result from algae.	Different levels form when varying amounts of water emerge from the springs.	The hot mineralized water can kill nearby vegetation.	moose (yes, there is one in this picture!) . . .

Moraines built by Pleistocene glaciers line many of the valleys of Yellowstone NP.	Algae or particular minerals may tint the mud various colors, as in the Fountain Paint Pots of the Lower Geyser Basin.	Mud pots are hot springs of boiling mud. Bubbles rise through the viscous liquid, then pop, leaving rings on the surface.	Springs and geysers in Norris Basin are hotter than any others in the park. This suggests that magma is nearest to the surface in that area.

Welcome to Yellowstone NP, home of Old Faithful.	Old Faithful erupts to a height of about 150 feet every hour or so, although the time between eruptions has increased since recent earthquakes in the area.	Eruptions have buried many forests in the Yellowstone area over the years. Then the wood may be replaced by silica from groundwater, producing petrified trees.	Most of the volcanic rocks here are rhyolite, an extrusive igneous rock rich in silica. Rhyolite is usually tan or gray, like these lava flows near Tower Falls on the Yellowstone River.

Tower Falls drops over the edge of a hanging valley carved in basalt.	The Upper Falls drops over a resistant ledge of rhyolite.	The Lower Falls drops over a resistant ledge of rhyolite.	This view across Hayden Valley shows Mount Washburn, one of the high summits that stood above the ice.

The sun sets over Yellowstone.	The mound of Castle Geyser is composed of geyserite, or siliceous sinter - a form of silica similar to opal.	In places, it is possible to peer through clear water into the depths of a hot spring.	Here, hot water rises through soluble limestone, bringing up > 2 tons of calcium carbonate per day! When the water reaches the surface and cools, a dense form of limestone called travertine precipitates in multi-level terraces.

In 1988, the Yellowstone region experienced devastating forest fires that even threatened historic buildings around Old Faithful. Decades of fire control had allowed dead wood to pile up on the forest floor, where it fueled huge blazes. In the aftermath, park rangers monitor the rejuvenation of the burned areas and reconsider fire control policies.	Upstream from Tower Falls lies theGrand Canyon of the Yellowstone.	Successive eruptions have produced over 3500 cubic kilometers of volcanic material. When this was removed from underground, the overlying rocks collapsed to form a caldera measuring 30 miles by 40 miles. The lowest part of the caldera is occupied by Yellowstone Lake.	The Yellowstone River flows placidly from Yellowstone Lake northward toward its Grand Canyon.