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Think of the red bluffs and cliffs of the Grand Canyon as Earth's history textbook, explained Barra Peak, lead author of the new study and a graduate student in geological sciences at CU Boulder. If you scale down the canyon's rock faces, you can jump back almost 2 billion years into the planet's past. But that textbook is also missing pages: In some areas, more than 1 billion years' worth of rocks have disappeared from the Grand Canyon without a trace. It's a mystery that goes back a long way. John Wesley Powell, the namesake of today's Lake Powell, first...

A group of University of Wyoming professors and students has identified an unusual belt of igneous rocks that stretches for over 2,000 miles from British Columbia, Canada, through Idaho, Montana, Nevada, southeast California and Arizona to Sonora, Mexico. “Geoscientists usually associate long belts of igneous rocks with chains of volcanoes at subduction zones, like Mount Shasta, Mount Hood, Mount St. Helens and Mount Rainer,” says Jay Chapman, an assistant professor in UW’s Department of Geology and Geophysics. “What makes this finding so interesting and mysterious is that this belt of igneous rocks is located much farther inland, away from the...

An intense temblor in Mexico was just the latest example of an enigmatic type of earthquake with highly destructive potential On September 7, 2017, a magnitude 8.2 earthquake struck southern Mexico, killing dozens and injuring hundreds. While earthquakes are common enough in the region, this powerful event wasn’t any run-of-the-mill tremor. That’s because part of the roughly 37-mile-thick tectonic plate responsible for the quake completely split apart, as revealed by a new study in Nature Geoscience. This event took place in a matter of tens of seconds, and it coincided with a gargantuan release of energy. “If you think of...

In our planet's early history, 720 to 640 million years ago, thick sheets of ice covered the majority of the surface, as the Earth was locked in a deep freeze. But explosive underwater volcanoes changed the chemistry of the Earth's oceans and were key to breaking the planet from its icy state, according to a new study. Researchers at the University of Southampton believe underwater volcanoes helped to thaw out "Snowball Earth", and even led to runaway chemical chain reactions, which created the conditions for an explosion of life on Earth. While much of the driving forces behind glaciation during...

It's long been held that North America's rugged and mountainous west was formed by the movement of the undersea Farallon plate, and that the process was roughly similar to the way groceries pile up at the end of a supermarket conveyor belt. Now however, a study published Wednesday in the journal Nature argues that the process involved not just one but several plates that remain hidden deep within in the Earth's mantle. Scientists at Ludwig Maximilians University in Munich and the British Columbia Geological Survey used earthquake shockwaves, or seismic tomography, to create a three-dimensional map of these massive plate...

New Haven, Conn. — The Gondwana supercontinent underwent a 60-degree rotation across Earth’s surface during the Early Cambrian period, according to new evidence uncovered by a team of Yale University geologists. Gondwana made up the southern half of Pangaea, the giant supercontinent that constituted the Earth’s landmass before it broke up into the separate continents we see today. The study, which appears in the August issue of the journal Geology, has implications for the environmental conditions that existed at a crucial period in Earth’s evolutionary history called the Cambrian explosion, when most of the major groups of complex animals rapidly...

Present-day nautilus shells almost invariably show thirty daily growth lines (give or take a couple) between the major partitions, or septa, in their shells. Paleontologists find fewer and fewer growth lines between septa in progressively older fossils. 420 million years ago, when the moon circled the earth once every nine days, the very first nautiloids show only nine growth lines between septa. The moon was closer to the earth and revolved about it faster, and the earth itself was rotating faster on its axis than it is now. The day had only twenty-one hours, and the moon loomed enormous in...

In their research, the scientists point to an earthquake that occurred off the coast of Portugal in 1755, which destroyed the city of Lisbon, and a 7.9-magnitude quake that struck the Portuguese capital in 1969. Duarte describes the newly-found “structure” in the tectonic plate as “a very good candidate” for the source of these events. “The 20 upper kilometers [12.4 miles] of the plate is made of soft rocks that are light and the bottom is dense and heavy (because the plate is very old, more than 100 million years),” Duarte told Fox News. “This causes this lower part to...

No boats required. In the distant future, most if not all of today's continents (brown fragments, depicted with current-day outlines) will assemble into a single landmass called Amasia (shown approximately 100 million years from now). Over the next few hundred million years, the Arctic Ocean and the Caribbean Sea will disappear, and Asia will crash into the Americas forming a supercontinent that will stretch across much of the Northern Hemisphere. That's the conclusion of a new analysis of the movements of these giant landmasses. Unlike in today's world, where a variety of tectonic plates move across Earth's surface carrying the...

America and Eurasia will crash into each other over the north pole in 50-200 million years time, according to scientists at Yale University. They predict Africa and Australia will join the new "supercontinent" too, which will mark the next coming together of the Earth's land masses. The continents are last thought to have come together 300 million years ago into a supercontinent called Pangaea. Details are published in the journal Nature. The land masses of the Earth are constantly moving as the Earth's as tectonic activity occurs. This generates areas such as the Mid-Atlantic Ridge, where Iceland has formed, and...