| Trap Mountain | |
| Elevation Ft: | 4122 |
| Elevation Ref: | [1] |
| Prominence Ft: | 1102 |
| Isolation Mi: | 1.70 |
| Isolation Ref: | [2] |
| Parent Peak: | Goat Mountain |
| Etymology: | Trap rock |
| Range: | Chisos Mountains |
| Country: | United States |
| State: | Texas |
| Region: | Brewster |
| Region Type: | County |
| Part Type: | Protected area |
| Part: | Big Bend National Park |
| Map: | Texas#USA |
| Label Position: | top |
| Coordinates: | 29.172°N -103.4277°W |
| Coordinates Ref: | [3] |
| Topo: | USGS Cerro Castellan |
| Age: | Oligocene |
| Rock: | Igneous rock (Rhyolite) |
Trap Mountain is a 4122feet summit in Brewster County, Texas, United States.
Trap Mountain is part of the Chisos Mountains where it is set in the Chihuahuan Desert and Big Bend National Park. The mountain is composed chiefly of Burro Mesa Rhyolite (volcanic rock) which formed 29 million years ago during the Oligocene period.[4] [5] Based on the Köppen climate classification, the mountain is located in a hot arid climate zone with hot summers and mild winters.[6] This climate supports plants on the slopes such as creosote bush, ocotillo, lechuguilla and yucca. Any scant precipitation runoff from the peak's slopes drains to the Rio Grande which is six miles to the southwest. Topographic relief is significant as the summit rises 1300feet above Ross Maxwell Scenic Drive in one-half mile (0.8 km). The mountain's toponym has been officially adopted by the United States Board on Geographic Names,[3] and has been listed in publications since at least 1914.[7] The mountain's name refers to trap rock,[8] which is any dark-colored, fine-grained, non-granitic intrusive or extrusive igneous rock. There are several large areas of dark rock on the west slope of the mountain visible from the Mule Ears Overlook below Trap Mountain.