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More than 3.8 billion years ago, in a time period called the Hadean eon, our planet Earth was constantly bombarded by asteroids, which caused the large-scale melting of its surface rocks. Most of these surface rocks were basalts, and the asteroid impacts produced large pools of superheated impact melt of such composition. These basaltic pools were tens of kilometres thick, and thousands of kilometres in diameter. “If you want to get an idea of what the surface of Earth looked like at that time, you can just look at the surface of the Moon which is covered by a vast...

Damage to the earth’s crust from the magnitude 6.4 and 7.1 earthquakes that struck Southern California last week is visible in a kaleidoscopic satellite image released by NASA. The Advanced Rapid Imaging and Analysis team at NASA’s Jet Propulsion Laboratory in Pasadena used satellite data to produce a map showing ruptures and displacements not visible to the naked eye — employing technology that has been developed over the last quarter of a century. The imagery was acquired on July 8 and compared with data from April 8. The earthquakes were the largest to hit California in nearly 20 years and...

The Grand Canyon is a gigantic geological library, with rocky layers that tell much of the story of Earth’s history. Curiously though, a sizeable layer representing anywhere from 250 million years to 1.2 billion years is missing. Known as the Great Unconformity, this massive temporal gap can be found not just in this famous crevasse, but in places all over the world. In one layer, you have the Cambrian period, which started roughly 540 million years ago and left behind sedimentary rocks packed with the fossils of complex, multicellular life. Directly below, you have fossil-free crystalline basement rock, which formed...

A drill will be used to extract samples of the exposed mantle Scientists are to sail to the mid-Atlantic to examine a massive "open wound" on the Earth's surface.Dr Chris MacLeod, from Cardiff University, said the Earth's crust appeared to be completely missing in an area thousands of kilometres across. The hole in the crust is midway between the Cape Verde Islands and the Caribbean, on the Mid-Atlantic Ridge. The team will survey the area, up to 5km (3 miles) under the surface, from ocean research vessel RRS James Cook. The ship is on its inaugural voyage after being...

The giant iron ball at the center of the Earth appears to be spinning a bit faster than the rest of the planet. The solid 1,500-mile-wide inner core, which is surrounded by fluid, rotates about one-quarter to one-half degree more than the rest of the world every year, scientists from Columbia University's Lamont-Doherty Earth Observatory and the University of Illinois at Urbana-Champaign report in today's issue of the journal Science. The spin of the Earth's core is an important part of the engine that creates the planet's magnetic field, and researcher Xiaodong Song said he believes magnetic interaction is responsible...