A tributary of the Grand Canyon, Little Colorado River Gorge juts east and south from the Grand Canyon’s Colorado River. The Little Colorado River Gorge is located on Navajo land in northern Arizona. The 16-million-acre Navajo Reservation is the largest of any Southwest tribe in America. In addition to Little Colorado River Gorge, many other scenic sites are located on Navajo land including Monument Valley, Canyon de Chelly and Rainbow Bridge in Glen Canyon.

The creation of Little Colorado River Gorge and the Grand Canyon is a result of the uplift that created the Rocky Mountains. As colliding continental plates squeezed the Rocky Mountains higher, the Colorado River, which had meandered the plains of this area, was now forced to rush downhill, carving a path to its new outlet in the Gulf of California. The charging river formed the Grand Canyon and its tributaries in four to six million years: a relatively short time, geologically speaking.

The Colorado River and the Little Colorado River exposed rock layers that record the passage of geologic eras. Most of the rock layers so evident in these canyons are sandstone and limestone. These sedimentary rocks are the result of marine and river deposits accumulating and compacting over millions and millions of years. The cave featured in the film formed in what’s known as Redwall limestone, a red-colored rock layer found high on the canyon walls. This Redwall limestone was deposited about 300 million years ago. The film’s cave was formed by acidic waters that seeped down through the limestone, just like other terrestrial caves are formed. The river exposed the cave as it continued to carve deeper into the canyon. Today the cave is more than 700 feet above the river!

Greenland is the largest island on Earth, measuring 1,659 miles long by 800 miles wide. Greenland lies largely in the Arctic Circle, so summers are cool and the winters are very cold. Summer temperatures range from 40 to 64 degrees Fahrenheit (5-18 Centigrade) and winter temperatures often never reach above zero (or –20 degrees Centigrade). An ice sheet, also called a continental glacier, covers 4/5 of Greenland’s land area. In some places the ice is 10,000 to 14,000 feet thick!

Our film crew flew into Kangerlussuaq (pronounced gong-ger-loosh-wok), a small town on the southwestern coast of Greenland. Only 60,000 people call this country home, most of who are of Inuit heritage. They reside in small towns along the fjords of the western coastline, where icebergs and ice floes (flat masses of frozen sea water) pepper the ocean waters.

Our crew journeyed by helicopter out onto the glacier with the ice cavers and scientists who explore the slow-moving sheet of ice. During summer months, the surface of the glacier forms meltwater, making rivers that run for miles. Where the rivers encounter a fault in the ice, they plunge downward, forming deep pits or caves hundreds of feet deep. Our film crew visited in September, after the caves formed and when the icy rivers begin to freeze again. When winter arrives, the cave entrances freeze shut. Even though the glacier itself moves very slowly, perhaps only a few inches each year, this movement may be enough to cause some of the new caves to collapse. Each spring, though, the rivers begin to flow and will excavate old caves and some new ones.