Part 12. Valles Caldera

Aerial view of the Caldera, photographed from American Airlines flight Albuquerque-Chicago.

Now only 1500 m/5,000' high, it had been much higher until its cone collapsed about a million years ago, forming a crater 20 km/12 miles across and 300 m/1,000' deep.

Aerial view of the Caldera. Grassy area of the crater floor is visible just above the center of the photo.

Satellite view of the caldera (courtesy USGS). Note San Diego Canyon to the south, a number of inner peaks of various size. The city of Los Alamos is just outside the right margin of the photo.

View of the Caldera from the crater rim, looking northwest. The small cinder cone in the center of the picture is also visible as a tiny dark dot at the center of the satellite photo to the left.

View down San Diego Canyon from the crater rim of the Caldera.

The crater was filled with a lake, which eventually drained through San Diego Canyon to the south. Later, smaller eruptions created numerous inner cones on the once-flat crater floor.

View of the Sandia Mountains from the summit of Redondo Peak.

View of the caldera floor. Redondo Peak is visible on the left.

View of Redondo Peak from the north. At 3380 m/11,254', it is the tallest of inner cones, and the highest point of the Jemez Mountains.

The eruptions, which ended just 50,000 years ago, had deposited layers of volcanic ash across large parts of North America. On the outer slopes of the caldera, they get as thick as 300 m/1,000'.

Caves in tufa layers, such as these at Bandelier National Monument, have been inhabited by people for thousands of years.

Kasha-Katuwe, or Tent Rocks - one of many interesting formations in eroding tufa deposits around the caldera.

Travertine deposits with algae, Soda Dam. Photographing inside the cave is very difficult: camera lens instantly get fogged.

Numerous hot springs are still scattered throughout the Jemes Mountains. The most interesting is Soda Dam - a huge wall of travertine, with a colorful cave containing a golden pool from which a hot stream is flowing (below).

The stream flowing out of the cave at Soda Dam contains weird balls of foam. They are the size of an orange, and slowly rotate in one place.

View of Soda Dam (left) and the hot spring inside the cave.

Coyote (Canis latrans).

The caldera, now partly a National Forest, partly a National Preserve, has been protected one way or another for decades. Alas, forest fires spreading from nearby city of Los Alamos have destroyed much of the forest, especially on the eastern side. There is still cattle grazing on the caldera floor, the most unique part of the Jemez. Limited elk hunting is also allowed.

Turkeys (Meleagris gallopavo).

Elk (Cervus canadensis).

Morning fog in the caldera.

Late September and early October, when the elk rut, aspen leaves turn yellow, and morning fogs fill the crater, is the most beautiful time of the year in the Caldera.

Morning fog around the Jemez Mountains.

Encounters between elk males seldom result in fights: usually they instantly know who is stronger, and the winner (left) chases away the weaker contestant (right).

Long-tailed vole (Microtus longicaudus).

Unless you are an elk hunter lucky enough to win the lottery, your access to the caldera is limited to National Forest lands and one short trail into the Preserve. Still, there's a lot to see there.

Long-tailed vole.

Montane vole (M. montanus).

Baby montane vole.

Dwarf shrew (Sorex nanus).

Western pocket gopher (Thomomys bottae) is more commom at lower elevations.

Pocket gophers (Thomomys) are very common in the caldera. Meadows and forests are dotted with their burrows; their digging activity improves the soils. They are brave and smart animals.

If caught in the open, Western pocket gopher doesn't hesitate to defend itself.

Baby Northern pocket gopher (Thomomys talpoides). This species is more common at higher elevations; it can usually be identified by large dark spots behind the ears. It is less aggressive than Western pocket gopher.

Western terrestrial garter snake (Thamnophis elegans).

The most interesting inhabitant of the caldera is Jemes Mountains salamander. It is an Ice Age relict, separated from its closest relatives on the Pacific Coast by almost a thousand miles of dry mountains and deserts. It has suffered a lot of habitat loss from forest fires, but is still common in some parts of the area.

Jemez Mountains salamander (Plethodon neomexicanus).

Common flowers of the caldera, left to right: false tahoka daisy (Machaeranthera tanacetifolia), chocolate flower (Berlandiera lyrata), Rocky Mountains iris (Iris missouriensis), birdcage evening-primrose (Oenothera deltoides).

Spotted coral root (Corallorhiza maculata).

The salamander's ability to survive here is probably due to relatively vet local climate. During the monsoon season (typically late July to early September), thunderstorms can be seen forming over the Jemez Mountains almost daily. Wet climate is also good for wildflowers - there's a lot of them here, including some rare species and many common, but beautiful ones.

Spotted coral root (Corallorhiza maculata).

Indian paintbrush (Castilleja linariifolia).

Mexican hat (Ratibida columnaris).

Jemez River flows out of the Jemez Mountains.

In winter, the Caldera gets more snow than most other parts of the state. Traveling off the main road gets difficult, but it's still a wonderful place to visit.

Patterns of ice on freezing Jemez River.

Winter in Valle Grande, the largest flat area inside the crater.

Aerial view of the Caldera in March, photographed from Delta Airlines flight Cincinnatti-Albuquerque.

In spring, snow remains inside the crater longer than elsewhere, often until April.

Aerial view of the Caldera in March. The crater floor has more snow than the surrounding hills.

Elk in the Caldera are among the largest in North America.

Home