Last updated: June 23, 2025
Place
Chisos Mountains Exhibit
NPS/CA Hoyt
Quick Facts
Location:
Big Bend National Park
Amenities
4 listed
Historical/Interpretive Information/Exhibits, Parking - Auto, Scenic View/Photo Spot, Wheelchair Accessible
This exhibit along the Ross Maxwell Scenic Drive briefly describes the volcanic formation of the Chisos Mountains, and names the prominent peaks and features visible from this location.
The exhibit text reads: "The Chisos Mountains rise nearly a mile above the Chihuahuan Desert floor, sprawling across 40 square miles (104 square kilometers). The only mountain range completely contained within a national park, the Chisos are the remnants of ancient volcanic activity that occurred between 38 to 32 million years ago.
The Chisos Mountains are mostly composed of rhyolite - a quartz-rick igneous rock. Eruptions of rhyolite are violent, explosive events, because the magma (molten rock) is thick, sticky, and gassy.
During the many eruptions that created the mountains, sprays of molten and pulverized rock, water vapor, and other gases created deadly, red-hot, fast-moving, avalanches called pyroclastic flows. Thick deposits from these flows later eroded to form the distinctive pinnacles you see along the Pinnacles Trail as you hike to Emory Peak - the highest point in the park.
Here, on the western side of the Chisos Basin, geologists think that thick, gooey magma flowed up out of a large semicircular fissure to form a string of lava domes that now enclose the northern and western sides of the Basin. Vernon Bailey Peak and Ward Mountain are particularly good examples of lava domes.
As you follow the Scenic Drive to the river, look for other volcanic landforms: the rhyolite dike that forms Mule Ears, the light-colored ash-flow deposits at Lower Burro Mesa and Tuff Canyon, and Goat Mountain's spectacular volcanic vent."
A square inset in the panel showing the Chisos Mountains from the air states: "A semicircular string of lava domes create a sky island where aspen trees tremble in mountain breezes and Colima Warblers nest in moist canyons. The Chisos sky island is surrounded by a desert sea of creosote and sharp-spined cactus - home to thousands of species adapted to hot, dry conditions."
The exhibit text reads: "The Chisos Mountains rise nearly a mile above the Chihuahuan Desert floor, sprawling across 40 square miles (104 square kilometers). The only mountain range completely contained within a national park, the Chisos are the remnants of ancient volcanic activity that occurred between 38 to 32 million years ago.
The Chisos Mountains are mostly composed of rhyolite - a quartz-rick igneous rock. Eruptions of rhyolite are violent, explosive events, because the magma (molten rock) is thick, sticky, and gassy.
During the many eruptions that created the mountains, sprays of molten and pulverized rock, water vapor, and other gases created deadly, red-hot, fast-moving, avalanches called pyroclastic flows. Thick deposits from these flows later eroded to form the distinctive pinnacles you see along the Pinnacles Trail as you hike to Emory Peak - the highest point in the park.
Here, on the western side of the Chisos Basin, geologists think that thick, gooey magma flowed up out of a large semicircular fissure to form a string of lava domes that now enclose the northern and western sides of the Basin. Vernon Bailey Peak and Ward Mountain are particularly good examples of lava domes.
As you follow the Scenic Drive to the river, look for other volcanic landforms: the rhyolite dike that forms Mule Ears, the light-colored ash-flow deposits at Lower Burro Mesa and Tuff Canyon, and Goat Mountain's spectacular volcanic vent."
A square inset in the panel showing the Chisos Mountains from the air states: "A semicircular string of lava domes create a sky island where aspen trees tremble in mountain breezes and Colima Warblers nest in moist canyons. The Chisos sky island is surrounded by a desert sea of creosote and sharp-spined cactus - home to thousands of species adapted to hot, dry conditions."