Sit beneath this wonder at sunset and you may never go home. Delicate Arch, near Moab, Utah is 52 feet tall. It's not the height that impresses, but the downright improbability of the structure. It formed over eons as the central portion of a fin of sandstone wore away, leaving the arch.
Oceans are really cool. Volcanoes are totally hot. The combination is electrifying, for those lucky enough to trek to Hawaii and watch planet-building in action. Here lava from a 2004 Kilauea volcano eruption flows into the sea. Volcanic processes are a prime builder of planets, creating
and reshaping everything from islands to mountains
.
and reshaping everything from islands to mountains
.
The granite monolith of Half Dome in the Sierra Nevada range of California is emblematic of the park's geology, characterized by granite rocks and remnants of older rock, all lifted into today's sharp relief about 10 million years ago.
This giant hole in the ground near Winslow, Arizona is a favorite tourist stopover, but also a less-than-gentle reminder that Earth is in the strike zone of large space rocks. Meteor Crater is 570 feet deep and 4,100 feet across. It was carved out 50,000 years ago by an asteroid roughly 130 feet wide.
A remarkable inlet is naturally carved naturally into the rocks at the seashore of Maine. As waves roll in, air and water is force through a small cavern and, with a loud clap like thunder, can shoot 40 feet into the air.
Cut from the Earth over time by the Colorado River, the Grand Canyon averages 4,000 feet deep for its entire 277 miles. It is 6,000 feet deep at its deepest point and 15 miles at its widest. Oddly, geologists aren't sure how old it is. Separate studies in 2008 put its age at either 6 million years or 16 million years.
Wizard Island pokes up in the middle of Crater Lake in Oregon. The lake, 1,943 feet deep, is the deepest in the United States. It was not made by a crater, however. Rather, it's a volcanic caldera — a giant basin made by the collapse of a volcano that erupted about 7,700 years ago. The region around the lake gets an average of 533 inches of snow per year — more than 44 feet.
On the border of Canada and the U.S. (New York), Niagara Falls formed when the last Ice Age receded. About 4 million cubic feet of water cascade down the 167-foot (52m) drop every minute
The Johns Hopkins Glacier, like a giant river of ice, meets the sea at Glacier Bay, a vast region where multiple glaciers meet, melt, and in some cases recede. In 1794, Captain George Vancouver and crew described the bay as just a small five-mile indent in a gigantic glacier that stretched off to the horizon. That massive glacier was more than 4,000 feet thick in places, up to 20 miles wide, and extended more than 100 miles to the St. Elias mountain range. By 1879, however, naturalist John Muir discovered that the ice had retreated more than 30 miles, forming an actual bay. By 1916, the Grand Pacific Glacier — the main glacier credited with carving the bay — had melted back 60 miles to the head of what is now Tarr Inlet.
An eruption at Old Faithful can send up to 8,400 gallons of boiling water shooting 145 feet or more into the air. The eruptions typically last more than a minute and up to 5 minutes. It is not as faithful as you might have assumed, going off in intervals that range from 45 minutes to 2 hours. It's all powered by molten rock (magma) beneath the surface. The whole Yellowstone Park area sits in a giant basin created by a supervolcano that last erupted about 620,000 years ago — one that will erupt again, in a big and devastating way, eventually.