Colorado's topography is extremely diverse, ranging from rolling foothills and towering mountains to stunning sand dunes, mesas, buttes, and grassy meadows. The terrain can significantly change within just a few miles, but that's part of what makes the Centennial State so special.

Another example of a unique geological feature found in Colorado is inverted topography.

Inverted topography is a landscape-altering process where low-lying areas become elevated relative to the surrounding landscape. There are several examples of this in the state.

One of these instances is present in Castle Rock. Millions of years ago, the prominent flat-topped butte, which is also the town's namesake, was the bottom of a rapidly flowing river. However, throughout the years, erosion wore away the land around the rock by more than 300 feet, while the erosion-resistant top layer of Castle Rock has remained largely unchanged. So, what used to be the lowest place is now the highest.

The natural landmark has three layers to it. The top layer is a distinctive rock that is called Castle Rock conglomerate. The middle section is a stone called rhyolite, which is the remnant of a colossal volcanic eruption. Finally, the bottom layer is known as the Dawson Arkose, created millions of years ago by fine sand and gravel deposited by moving water.

Kelsey Nistel, TSM/Canva
Kelsey Nistel, TSM/Canva
loading...

The Grand Mesa in western Colorado is another example of topographic inversion. It is also the largest flat-topped mountain in the world. The topography of the Grand Mesa area formed in response to late Cenozoic downcutting of the upper Colorado River system. Basalt flows from the Grand Mesa Volcanic Field filled the valleys, and are now positioned on the watershed divide between the Colorado and Gunnison Rivers.

The mountain's flat top abruptly ends at the edge of towering cliffs, which plunge several hundred feet downwards towards the forests below. The mesa is topped by a hard layer of volcanic basalt, surrounded by many sedimentary rock layers. The lowest sections of the mesa are made up of yellow and gray Mancos Shale of late Cretaceous age.

Google Maps
Google Maps
loading...

The Colorado Piedmont is a third representation of inverted topography. The mesas and buttes in this area along the base of the foothills of the Front Range are capped by Eocene-age conglomerates and tuffs that were originally deposited in topographic lows.

Current geologic theories explain the Piedmont was formed approximately 28 million years ago, during the broad bowing of the North American Plate. This massive uplift resulted in increased streamflow and rapid erosion on the eastern side of the Rocky Mountains. The erosion scraped away the top layer of Upper Cretaceous sandstone, exposing the underlying layer of Pierre Shale. During this time, the South Platte River, which had previously flowed eastward across the Plains, rerouted northward along the mountains to join the Cache la Poudre River. In some areas of the Piedmont, a loose veneer of Pleistocene gravel sits above older shale which accumulated during glaciation in the mountains, when streams descending onto the Piedmont became overburdened with sediment

The drop-off from the High Plains to the Piedmont can be seen by motorists driving southward from Cheyenne on I-25.

Incredible instances of inverted topography can also be seen in St.George, Utah, and Black Mesa, Arizona.

Northern Colorado Let Us Know Their Favorite Colorado Landmarks

Don't know what to do with an out of towner? Northern Colorado came together and has some suggestions.

Gallery Credit: Tanner Chambers

More From 94.3 The X