Lake Tahoe, California

White Sands National Monument, New Mexico

I arrived at the park an hour before sunrise and hiked as far as I could manage before the sun came up.  It was uncharacteristically freezing that morning (15°F/-9°C) and I wasn't prepared.  My hydration pack was frozen solid and my boots were not rated to handle the extreme conditions.  I was literally scared I'd suffer frostbite on my toes.  Luckily, I came out unscathed.  Lesson learned.

White Sands National Monument, New Mexico

The soaptree yucca (Yucca elata) is native to the American Southwest and parts of Mexico and is named after the soap-like substance found inside the roots and trunk of the plant. The leaf fibers were used by Apaches to make rope and dental floss. This perennial plant grows to between one and four meters in height.

White Sands National Monument, New Mexico

It may look like snow, but these are actually rare phenomenon: sand dunes made of white gypsum.

Mono Lake, California

Truly a curiosity of nature, the geological formations of Mono Lake are unusual, to say the least.

A particular chemical balance is required for these formations to develop over time; conditions believed to be similar to what can be found on Mars.

Mono Lake, California

These "tufa towers" are comprised of calcium-carbonate, the same compound that makes limestone, and can rise up to 10 meters high.

Although they were formed by the alkaline lake water interacting with the freshwater springs, the details of the exact process is still to be determined by scientists.

Mono Lake, California

Nearby, on the adjacent dry land are sand-tufa structures consisting of pumice sand which was cemented by calcium carbonate.  

Formerly underwater, these resilient structures remained after the lake receded.

Death Valley, California

Death Valley, California

Badwater Basin, Death Valley, California

The lowest point in North America, this is 282 ft (86m) below sea level.  The white lines are salt formations crystalizing.