Unique Geological Features

Organ Mountains Complex

The Organ Mountains tower nearly 5000 feet above the Mesilla Valley and Tularosa Basin. Overlooking Las Cruces to the west and White Sands National Monument to the east, the Organs are visible from 100+ miles in every direction during clear days. Their geology contributes to this spectacular scenery and to a wide array of recreational opportunities that help make “the Organs” one of New Mexico’s most recognized and important landmarks.

Organ Mountains by Mike GrovesThe Needles, standing at 8,990 feet, are the range’s most prominent feature. These granite peaks were created, according to geologist W.R. Seager, by pyroclastic flows and lava almost 34 million years ago. Now, the smooth granite and spectacular views draw climbers from all over the world. A non-technical route rated as New Mexico’s most difficult day hike also allows non-climbers to savor the same experiences. As Seager puts it, “Their stark, sawtooth profile, their challenging slopes and changing moods have made the Needles a favorite of artists, photographers, and mountain climbers, as well as a daily pleasure to the people who live within their view.”

South of the needles rise successive folds of igneous rock partially created through continued faulting in the area. Soledad Canyon slices through this section of the mountains providing the easiest east-west transit south of Baylor Pass. Even though only partially open, the Soledad Canyon trail and day use area receive a steady stream of visitors ranging from local horsemen to young families to many local senior citizen groups. Limestone constitutes the lower and more rounded peaks south into the Peña Blanca and Bishop’s Cap area. Area where caves still show evidence of ancient peoples and dispersed desert recreation is at its finest. On the Organ Mountain’s eastern side sits Doña Ana County’s only high country campground, located at Aguirre Springs. Massive Sugarloaf Peak’s granite exterior and rugged Indian Basin loom in stark relief to White Sands National Monument.

Sierra de Las Uvas Mountains Complex

Robledo Mountains by Adriel-HeiseyThe Sierra de Las Uvas Mountains complex is a treasure trove of unique geologic, cultural, and biological features. The Robledo Mountains are a limestone mountain range that scientists believe began as an “alluvion”, or a land area created through sediment built up as water, in this case an ancient sea, receded. This phenomenon gave rise to the internationally significant Paleozoic Trackways site, partially excavated and containing pre-dinosaur fossil trackways that are an estimated 280 million years old. Known as a “megatracksite” and home to the United State’s 100th National Monument, the Trackways are the southern anchor of this wildland complex. The Robledo Mountains limestone structure boasts numerous caves. One of the Robledo Mountains most famous features, Geronimo’s Cave, was said to be the site of one of his many escapes, where a band he led traversed east to west through the mountains and left the pursuing cavalry waiting futilely near the eastern entrance of the cave as the Apache road west to the Gila. The Robledo Mountains take their name from Pedro Robledo. Pedro Robledo drowned in the Rio Grande near the peak and mountain range that bears his name. Descendants of Pedro’s granddaughter reside in Las Cruces today, including Former State Representative and cultural icon J. Paul Taylor.

Broad Canyon with hikersNorth of the Robledo Mountains is the Broad Canyon Country. Expansive canyon views suddenly narrow to sheer rock gorges and narrow passageways of conglomerate are concentrated around many of the area’s sinuous curves. Draining over 200 square miles, Broad Canyon is a dominant terrain feature that also serves as a wildlife funnel between the Rio Grande and the Sierra de Las Uvas, and from there to the Black Range Mountains of the Gila. The exposed Cenozoic geology laid bare through Broad Canyon’s continuous water contouring draws academics and aficionados alike. Bedrock tinajas that collect and hold water even during dry periods were undoubtedly important to the varied wildlife and native peoples that used this land. Much as today’s Broad Canyon is a critical habitat “highway” for area wildlife, evidence points to its use as part of trade routes used by Archaic and Jornada Mogollon cultures.

Sierra de Las Uvas-Approaching Storm by Lisa MandelkernThe Sierra de Las Uvas are the northern bookend to this wildland complex. Their rimrock mountain mesas evoke north central New Mexico, but this north trending fault block is one of southern New Mexico’s biological gems. The lush, broad mesa tops support thriving black grama grasslands complimented by the mountain mahogany and oak shrub system that supports a healthy desert mule deer herd. There is basaltic rimrock ringing the flat mountain mesas. Souse Springs provides much of the Village of Hatch’s water supply, and is also the location of the famous wild grapes that helped give these mountains their name. Skirting the southern edge of the mountains is the historic Butterfield Stage Route, which runs by the ominously named Massacre Peak. The stop at Fort Mason is still visible, and nearby petroglyphs evoke the rich, deep cultural history of the Sierra de Las Uvas.

Potrillo Mountains Complex

Potrillo CraterThe Potrillo Mountains complex is awash in volcanic diversity filled with maar craters like Kilbourne Hole, hundreds of Cinder Cone Peaks, and shield volcanoes like Aden Crater. This rare and unique combination conceals many treasures. In 1928, one of the few fossilized ground sloths ever recovered with intact areas of skin and hair was found in a fumarole on Aden Crater. Archaeological evidence shows ancient peoples have been using this dramatic landscape for nearly 10,000 years, and buried in this geologic wonderland are remnants from a well preserved Mimbres Era Pueblo. In 1900, 40 Desert Bighorn Sheep were slaughtered in the West Potrillo Mountains and shipped to a Deming meat market, despite an 1889 ban on hunting the endangered animal. Intact, remote habitat makes this area a candidate for reintroduction of this endangered species, and Desert Pronghorn Antelope could also be reintroduced due to habitat improvements through collaborative local grassland restoration projects. Rare and rugged, the landscape has also served as a training ground for the original Apollo Moon missions, authoring yet another chapter in this storied landscape’s history.