Sedona red rocks are legendary. Sedona AZ owes much of its awe-inspiring beauty to its distinctive geographical location. Sedona sits at the southern escarpment of the Colorado Plateau, a vast upland extending into the four corner states, Arizona, Utah, Colorado and New Mexico. This plateau has an elevation of about 7000 feet and roughly the size of the state of Arizona. About 80 miles to the north of its southern escarpment, the Grand Canyon is majestically carved into this plateauThe region around Sedona AZ is geologically unique - and in some respects even exciting, for it is still experiencing uplift. If you sit real still and hold your breath, you might feel it! The rate of uplift amounts to a few millimeters a year, or about an inch over the course of a human lifetime – but in geological time, this is considered some pretty swift movement.
From a geological perspective, the surface of our planet with all its crinkles, folds and creases is shaped by the immense pressures at work in the slow collision of the continental plates. Typically, these pressures are acknowledged in the folding and faulting of mountain ranges. But the Colorado Plateau, reacting on pressures formed between the North American and Pacific plates, is unique - this region is rising fairly uniformly, as one huge unit. And although the geological mechanism by which the Colorado Plateau rises is understood, the reason why the uplift is uniform remains a geological mystery.
The uplifting Colorado Plateau has been hugely influential in shaping the landscape and appearance of Sedona's red rocks and the American southwest. As the land continues to rise, rivers, creeks and streams respond by either changing their course to continue flowing to lower ground, or to carving down into the rising landmass. This so-called differential erosion has shaped - and in many cases continues to shape - the breathtaking beauty of the Southwest, the bizarre shapes and amazing forms of National Parks such as Bryce Canyon, Zion Canyon, Canyonland, Arches and, of course, the Grand Canyon.
Among the fascinating effects of the uplift of the Colorado plateau is the exposure of sedimentary strata hundreds of millions of years old. If you look at Sedona´s red rocks, you may notice horizontal stratas of various widths and colors. These strata are sedimentary layers; a schooled geologist might read these strata like a timeline or picture book of the earth´s history.
Sedimentary rocks give us a glimpse into specific past ecosystems and environments that once resided in a given location. For example, the type of rock that would form in a swamp, marsh, delta or shallow marine environment is called Shale. The rock type known as Sandstone develops in environments where one would find sand; namely, beaches and dunes. Finally, Limestone is formed on ocean floors.
The canyon walls in Sedona reach about 2,000 feet, but they contain evidence of this area´s geological history as far back as 300 million years. Their composition speaks of ocean floors 250 million years old and of ancient sand dunes. These walls tell us that where now lies a desert, ocean waters once rolled. They are not only stunningly beautiful, they also bear witness to the fact that ours is a living planet.
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