Grand Canyon Geology

A Grand Canyon tour literally rocks because you get to learn a lot about Grand Canyon geology. If you want to find out more about how rocks and canyons form, you can get a good deal of insight when you explore the South Rim in Grand Canyon National Park. This scenic area will introduce you to the history of rocks, and give you a first-hand look at the geology of the canyon.

The Oldest Layer

The oldest rocks in the canyon are Precambrian basement rocks. These rocks formed deep under the Earth’s surface, and make up the metamorphic rock known as Vishnu Schist. The rocks developed when molten rock in the form of magma flowed up between crevices of the Vishnu Schist. This rock, when cooled, hardens into granite.

The Second Oldest Layer

The bright angel shale rock of the canyon formed about 515 million years ago. If you had seen the canyon area during this time, it would have been enveloped in a warm and muddy shallow sea. Trilobites, crinoids, and brachiopods burrowed in the ocean floor and thrived in the nutrient-rich waters. The shale, greenish in hue, can be found in the flat and wide area of the canyon’s Tonto Platform.

The Third Oldest Rock Form

Around 340 million years ago, the North American continent lied near the equator. That is when the redwall limestone of the Grand Canyon geology was formed. Fossils in this rock layer tell scientists that cephalopods, byrozoans, brachiopods, and corals lived in the sea at the time. While limestone is normally grey, the surfaces of exposed limestone cliffs take on a red color, resulting from the iron in the rock, and the erosion caused by rain and snow melt.

The Fourth Oldest Rock Layer

The Supai group of Grand Canyon geology rocks formed about 300 million years ago. During this time, the sea levels were constantly rising and falling. The Supai group represents rock material containing sandstone, shale, and limestone. While sea environments left behind fossilization in the form of brachiopods, terrestrial environments left behind plant fossils. Both types of the environments featured burrowing animals.

The Fifth Oldest Rock- Hermit Shale

About 280 million years ago, the Grand Canyon was covered with a coastal plain, which received the waters of various streams. The environment served as a habitat for conifers and ferns, as well as dragonflies with three-foot wingspans. The hermit shale layer is made up of fine-grained sandstones, mudstones, and siltstones, all rich in iron. This rock layer creates gentle red inclines in the South Rim of Grand Canyon National Park

Take A Tour To Learn More Grand Canyon Geology

You can learn more about the interesting history of Grand Canyon geology by taking one of the Grand Canyon Tour packages featured to the South Rim. Obtain more information today by contacting the popular Las Vegas tour operator, Grand Canyon Destinations.