There is a place on the western rim of the Las Vegas Valley where you can lay a hand flat against a line in the rock and feel two impossible things touching. Below your hand, red sandstone. Above it, gray limestone. And the wrong one is on top — the gray rock is far older than the red, which is precisely backwards from the way the world is supposed to be stacked, younger over older, like the pages of a book. At the Keystone Thrust, in Red Rock Canyon, the book has been turned upside down, and the seam where it happened is right there to touch.
That seam is the key to three of southern Nevada's great landscapes, which look like three different worlds and are really one story told in two colors. The fire-red cliffs of Valley of Fire, the red-and-gray escarpment of Red Rock Canyon, and the pale, snow-streaked heights of Mount Charleston are chapters of a single deep-time account: a sea, a desert, and the slow tectonic shove that stacked one on top of the other and then lifted the whole pile into the sky.
The sea
Begin at the bottom, with the gray. For most of the Paleozoic — from roughly 600 million years ago onward, across hundreds of millions of years — what is now southern Nevada lay under warm, shallow tropical seawater. The coastline ran through present-day Utah; everything west of it was ocean. Generation after generation of marine life lived and died and settled to the bottom, until their shells and skeletons had piled up thousands of feet thick on the sea floor, compressing under their own weight into limestone and other carbonate rock. The gray stone that caps the high country here is, quite literally, the bottom of a vanished ocean — packed with the wreckage of creatures that needed salt water to live.
The desert
Then the sea drained away. By the Jurassic, around 180 to 190 million years ago, the ocean was long gone and the region had become the opposite of a sea: a vast, bone-dry desert of wind-driven sand on the scale of the modern Sahara, burying much of the American Southwest under dunes. Those dunes hardened, grain by grain, into the Aztec Sandstone — the same rock that forms the cliffs of Zion up in Utah, where it goes by the name Navajo Sandstone. Look closely at the great red walls and you can still read the desert in them: the long, sweeping cross-bedding is the frozen face of moving dunes, a record of which way the wind blew a hundred and eighty million years ago, and the deep red is nothing but rust — iron in the old sand, oxidized over the eons. Valley of Fire is this fossil desert at its most concentrated, a whole park of petrified dune; dinosaurs walked across it, and their tracks are pressed into the same stone.
The wrong way up
So far the order makes sense: older sea on the bottom, younger desert on top. Then, about 65 million years ago, the order broke. Far to the west, an oceanic plate was grinding down and under the edge of North America, and the squeeze of it rippled inland, compressing the crust and driving great slabs of rock eastward — the mountain-building episode geologists call the Sevier Orogeny. One of those slabs was the old gray sea-floor limestone, and it was shoved up and out over the top of the younger red desert sandstone, riding miles to the east along a fracture now called the Keystone Thrust. The result is the inversion you can put your hand on: ancient marine limestone resting directly on younger desert sandstone, gray over red, old over young. Red Rock Canyon holds one of the cleanest, most legible thrust faults exposed anywhere on Earth — gray Turtlehead Peak, standing above the red sandstone, is the upper plate, caught mid-shove and frozen there for sixty-five million years.
The sea in the sky
That same eastward shove did something even stranger a little to the north. It carried the gray sea-floor limestone not merely over the desert but high into the air — and the highest it went is Mount Charleston, whose summit ridge tops out near 12,000 feet. The pale rock of Charleston Peak is that same drowned tropical sea floor, hauled almost two miles into the sky, where it now wears winter snow and grows bristlecone pines — the oldest living things on the planet — straight out of stone that an ocean laid down. It is the last and most extreme version of the inversion: a seabed turned into an alpine summit, marine rock standing above the clouds.
Fire and limestone
Stand back, and the three landscapes resolve into one. The red is the desert; the gray is the sea; and the shape of the whole place is the story of the sea being driven up over the desert and then lifted into mountains. In a single hour you can stand on the petrified Sahara at Valley of Fire, lay your hand across the seam at Red Rock where the ocean overrode the dunes, and look up at the snow on Mount Charleston, where that same ocean floor rides highest of all. The fire-red rock and the cold gray heights are not different worlds. They are the same deep time, stacked the wrong way up — a sea on top of a desert, somehow still holding.