The Grand Staircase is the dominant geologic feature of the Colorado Plateau. The Grand Canyon is one small part of the Grand Staircase. There is nothing else on Earth like the Grand Staircase, which is so large it cannot be seen, it must be imagined. The Grand Staircase is a series of high plateaus piled one on top of another, much like a flight of stairs starting at the bottom of the Grand Canyon, more that 1,000 feet below sea level, and rising to 10,450 feet on Boulder Mtn., aka the Aquarius Plateau.
Geologists flock to the Grand Staircase for its unique scientific importance. The Grand Staircase is the only place on Earth where the entire geologic history of the world, more than three billion years, can be seen without having to dig holes. Pre-Cambrian rock, the Earth’s oldest surface rock, is exposed near the bottom of the Grand Canyon. The Aquarius Plateau is capped by the youngest.
You can picture the Grand Staircase as a flight of stairs, but ultimately that image fails because stairs go up, then go flat, then go up again, etc., but not the Grand Staircase. The first step up from the very bottom of the Grand Canyon is a big one, 8,000 feet, to the Kaibab Plateau. But the Kaibab is not flat. It drops about 3,000 feet as you travel north to the foot of the next step, the Vermillion Cliffs, which rise 2,000 feet above the valley floor but top off 1,000 feet lower than the top of the step out of the Grand Canyon. Look up Grand Staircase on Wikipedia. There is a good NPS 3-D drawing illustrating its structure.
Where did the Grand Staircase come from? For more than 1.5 billion years, the surface of the Colorado Plateau went up and down, as the continents shifted around the surface of the planet. The down cycles took the surface of the Colorado Plateau hundreds of feet below sea level, and it became part of the oceans. Erosion of the surrounding land carried sand into this shallow sea, where it formed sandstone. Then the Earth shifted, and lifted the sea floor well above sea level—today’s Colorado Plateau is 600-14,000 ft. above sea level—and what was once water became desert where occasional rain eroded the sandstone, covering the surface of the world’s biggest desert* with sand. Winds blew the sand into great sand dunes. When the earth sank under the seas again, these sand dunes were also transformed into rock. The petrified sand dunes are best seen driving into Zion National Park from the east on UT Rt 9, and are easily identified by the erratic strata in the rock which were formed by the shifting of the winds piling up sand from every which way.
The last time the earth rose and pushed what was at the bottom of the sea up above sea level, it pushed the eastern side of the Colorado Plateau up faster than the west so that rainfall on the western slopes of the mountians in Colorado drained to the west, across the Colorado Plateau, creating today’s Colorado River. As the land slowly rose, the river cut a great canyon down through the slowly rising rock near the end of its journey across the Colorado Plateau—the Grand Canyon. Although desert, rain gradually wore away the softer rocks, leaving behind towering plies of harder rock that were more resistant to erosion, the plateaus that now form the Grand Staircase.
The youngest rock strata exposed in the Grand Canyon is the oldest rock seen in Zion Canyon.
The youngest rock at the top of the cliffs of Zion Canyon is the oldest rock at the bottom of Bryce Canyon.
On the Grand Staircase, tourists find some of the most amazing scenery on Earth, the Grand Canyon, Zion National Park, Bryce Canyon in the side of the Pink Cliffs, Grand Staircase, Escalante National Monument, and the rugged back country of the Vermillion, White, Grey, and Black Cliffs. The rocks of the Grand Staircase come in every possible color for rock: red, yellow, black, green, white, orange, tan, and grey. Red is the dominant color, giving its name to the commonly used expression for this part of the continent, Red Rock Country.
Capitol Reef, although part of the same geologic province as Grand Staircase, is not part of Grand Staircase itself. Back to mental images; picture the Grand Staircase as a layer cake cut through from the top at an angle, then one side of the cake removed to expose the layers to view from the side.
That’s the Grand Staircase. Capitol Reef is a giant wrinkle in the layers, at almost a right angle to the exposed side of the cake.
Looking west from the west side of the Reef, the tall dark mountain defining the western horizon is Boulder Mtn., called the Aqurius Plateau from the other side, and the top step of Grand Staircase.
The best way for the visitor to see the Grand Staircase is by driving from the north rim of the Grand Canyon to Sunset Point in Bryce Canyon National Park. After dropping down into the desert from the forests on the Kaibab Plateau, the Vermillion Cliffs are the ridge disappearing into the distance on the right. Between Kanab and UT Rt 14, there are occasional glimpses of the White Cliffs to the right of US 89. From Sunset Point, look down at the Pink Cliffs, and out to the left to see the Aquarius Plateau.
* The Sahara Desert is small time compared to the desert that helped create Zion National Park.