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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...

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...

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...

A new map reveals the remnants of ancient continents that lurk beneath Antarctica's ice. The map shows that East Antarctica is made up of multiple cratons, which are the cores of continents that came before, according to study leader Jörg Ebbing, a geoscientist at Kiel University in Germany. "This observation leads back to the break-up of the supercontinent Gondwana and the link of Antarctica to the surrounding continents," Ebbing told Live Science. The findings help reveal fundamental facts about Earth's tectonics and how Antarctica's land and ice sheets interact, he wrote in an email. Because the continent is so remote...

The newly-reported specimen was obtained from an amber deposit in the Angbamo area in Myanmar’s Kachin province.The fossil is a 1.6-inch (4.75 cm) long postcranial skeleton made up of 97 vertebrae; the snake’s head is missing. It dates from the Late Cretaceous epoch, approximately 99 million years ago.“This snake, named Xiaophis myanmarensis, is linked to ancient snakes from Argentina, Africa, India and Australia,” said University of Alberta’s Professor Michael Caldwell.“It is an important — and until now, missing — component of understanding snake evolution from southern continents, that is Gondwana, in the mid-Mesozoic.” “At 99 million years old, it dates...

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...

Colored polygons represent different geological units that have been mapped (and inferred) by geologists over many years. These geological units formed before the continents broke apart, so we can use their position to put the "jigsaw pieces" back together again. Many other reconstructions do not use the geological boundaries to match the continental "jigsaw pieces" back together - so they don't align properly. Courtesy of University of Royal Holloway London A new study published in the journal Gondwana Research, has revealed the past position of the Australian, Antarctic and Indian tectonic plates, demonstrating how they formed the supercontinent Gondwana 165...

An Argentine-Swedish research team has reported a 70-million-year-old pocket of fossilized bones and unique eggs of an enigmatic birdlike dinosaur in Patagonia... The dinosaur represents the latest survivor of its kind from Gondwana, the southern landmass in the Mesozoic Era. The creature belongs to one of the most mysterious groups of dinosaurs, the Alvarezsauridae, and it is one of the largest members, 2.6 m, of the family. It was first discovered by Dr. Powell, but has now been described and named Bonapartenykus ultimus in honor of Dr. José Bonaparte who 1991 discovered the first alvarezsaurid in Patagonia... The two eggs...