The mountains are located near the western margin of the Rio Grande Rift, a major structure that stretches from the vicinity of Leadville, Colorado, through central New Mexico, and into the Mexican state of Chihuahua.

The basal rocks in the range are sedimentary, and consist of limestone, dolomites, and silty beds of Middle Permian age.

Over half of the annual precipitation falls in the form of summer rains between June and September, although some snow can be expected in the winter.

Precipitation quickly evaporates, runs off, or soaks into the ground, leaving little for plants or animals.

This can result in great species variation between communities that happen to be located on slopes with different aspects.

Common animals/ mammals include mule deer (Odocoileus hemionus), coyotes (Canis latrans), Black-tailed jackrabbit (Lepus californicus), desert cottontail, (Sylvilagus auduboni) and kangaroo rats (Dipodomys merriami and Dipodomys spectabilis).

Common birds include golden eagles (Aquila chrysaetos), Swainson's hawk (Buteo swainsoni), Northern harrier (Circus cyaneus), burrowing owl (Athene cunicularia), roadrunner (Geococcyx californianus), quail (Callipepla gambelii and Callipepla squamata), doves (Zenaida macroura and Zenaida asiatica).

Of particular interest to visitors are a series of nearby maare, or phreatomagmatic craters, which are located approximately 5–10 miles to the north and east of the main spine of the range.

The Bureau of Land management considered, but rejected Wilderness Study Area status for a 26,300 acre unit that includes the range.

Full wilderness status for this area was proposed, but defeated in the lame duck Congressional session of 2010.

This was largely due to a desire for a "buffer" zone along the border and a perception that wilderness status would inhibit the detection of illegal immigrants.