![]() The oldest dated zircons date from about 4,400 million years ago. The Hadean Eon is not formally recognized, but it essentially marks the era before we have adequate record of significant solid rocks. Main article: Hadean Artist's conception of a protoplanetary discĭuring Hadean time (4.6–4 Ga), the Solar System was forming, probably within a large cloud of gas and dust around the Sun, called an accretion disc from which Earth formed 4,500 million years ago. Plate tectonics from the Neoproterozoic to present The last glacial period of the current ice age ended about 10,000 years ago. The polar regions have since undergone repeated cycles of glaciation and thawing, repeating every 40,000–100,000 years. The present pattern of ice ages began about 40 million years ago, then intensified at the end of the Pliocene. The continents later recombined to form Pannotia, 600 to 540 million years ago, then finally Pangaea, which broke apart 200 million years ago. Roughly 750 million years ago, the earliest-known supercontinent Rodinia, began to break apart. They migrated across the surface, occasionally combining to form a supercontinent. Īs the surface continually reshaped itself over hundreds of millions of years, continents formed and broke apart. However, in 2020, researchers reported that sufficient water to fill the oceans may have always been on the Earth since the beginning of the planet's formation. Condensing water vapor, augmented by ice delivered from comets, produced the oceans. Outgassing and volcanic activity produced the primordial atmosphere. The Moon formed soon afterwards, possibly as a result of the impact of a planetoid with the Earth. Eventually, the outer layer of the planet cooled to form a solid crust when water began accumulating in the atmosphere. Initially, the Earth was molten due to extreme volcanism and frequent collisions with other bodies. Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the Solar System. The geological history of Earth follows the major geological events in Earth's past based on the geological time scale, a system of chronological measurement based on the study of the planet's rock layers ( stratigraphy). Geologic time shown in a diagram called a geological clock, showing the relative lengths of the eons of Earth's history and noting major events Hungry for some science, but you don’t have time for a full-course research plate? Then check out USGS Science Snippets, our snack-sized science series that focuses on the fun, weird, and fascinating stories of USGS science.For broader coverage of this topic, see History of Earth. ![]() It also reveals the distinct, circular Upheaval Dome on the northern border of Canyonlands, a formation that geologists say was either created by a meteorite impact or by the movement of salt layers deep underground. Landsat imagery captures the deeply cut meanders and oxbows carved out by ancestral rivers in the national park. ![]() The least accessible district, the Maze, is a remote labyrinth of deep canyons set against a landscape of standing rocks above it.īut Canyonlands' colorful beauty doesn't end there. The Needles District in the southeast corner of Canyonlands takes its name from the colorful spires of Cedar Mesa Sandstone that dominate the area. Perhaps the most accessible district is Island in the Sky, a relatively flat mesa that rises 600 meters above the Green River to the west and the Colorado River to the east. In the high desert of the Colorado Plateau, countless canyons, mesas, and buttes have emerged over millennia from the eroding forces of water and gravity across the park's 1,365 square kilometers (527.5 square miles). The Horseshoe Canyon Unit is the detached part of the park in the upper left corner of the image. No paved roads exist to join together the park's three main districts-Island in the Sky, the Needles, and the Maze. In this 100th anniversary year of the NPS, the Operational Land Imager (OLI) on Landsat 8 has acquired a stunning, false-color image that enhances the park's irregular topography. In September 1964, Interior Secretary Stewart Udall successfully shepherded some of the most remote and rugged terrain within the continental United States into the jurisdiction of the National Park Service (NPS) with the creation of Canyonlands National Park in southeastern Utah. The EarthView: Water, Gravity Carve Out Magnificent Canyonlands Landsat 8's view of Canyonlands National Park.
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