![]() Upheaval Dome is another interesting feature of the Island in the Sky district. This site is a popular hiking trail where hikers can spot the ancient sand dune deposits of the Navajo sandstone. A strip of land called “the neck” serves as a physical barrier between Island in the Sky and the neighboring land of the Colorado Plateau. Here, harder rock shelters weaker rock underneath, creating beautiful tower formations. Monument Basin is another spot within Island in the Sky where hard rock left behind has become an unusual formation. Layers of sedimentary rock are visible down the steep walls of canyons cut from the top of the mesa to the rivers far below, exposing roughly 150 million years of geologic history.įrom river level, the Honaker Trail limestone can be spotted, while harder sandstone forms “benches” on top of the cliffs. Island in the Sky is a 2,000 foot-high mesa overlooking the Green River to the west and the Colorado River to the east. Paper Powell, the USGS mascot from the150th anniversary of the John Wesley Powell expedition, visits the Island in the Sky Visitor Center in Canyonlands National Park. ![]() Wind erosion in this area is a topic of current USGS research, as is water. All of these processes are ongoing, meaning that the stunning formations we see today will eventually be worn away by erosion. Infrequent, yet heavy rains surge down the mountains, carrying sediment within its load. Ice freezing within cracks widens the cracks even more, known as frost-wedging. This desert region averages over 5000 feet above sea level, where snow and ice are present during the winter months. Water, ice, and wind continue to shape the park today. Today, these mountain ranges tower above the softer sedimentary rocks in the valleys below.Īs the Colorado Plateau continued to rise, rivers continued to carve deeply into the rock, revealing layer upon layer of ancient sediments deposited millions of years earlier, incising existing river meanders and exposing a treasure trove of Earth’s geologic history. During this uplift, magma, or molten rock, also moved into the sedimentary rocks along cracks, hardening into the igneous rocks of the nearby La Sal, Abajo, and Henry Mountains. Instead, stronger sandstone forms steep cliffs and ledges, softer shale forms slopes, and the landscapes have been shaped over time into the interesting landforms we see today.Ībout 20 million years ago, that began to change as the entire region of the Colorado Plateau was uplifted, or pushed upward, by tectonic activity. If they were, the landscape would be significantly less dramatic. Not all the sedimentary rock types are the same. As these sediments piled up over time, they lithified (turned to rock through compaction and cementation) into a layer cake of sedimentary rocks, each layer recording the buried record of time and life on Earth. Sediments such as sand and mud were originally deposited near sea level by ancient seas, lakes, marshes, salt flats, and sand dunes. Throughout the park, millions of years of geologic history are visible at every turn. ![]() ![]() Landsat 8 image of Canyonlands National Park and the surrounding area. ![]()
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