The eastern Grand Canyon was about half-carved (to the level of the red cliffs above the hiker) from 15 million to 25 million years ago, an analysis published Sunday suggests. But the inner gorge was likely scooped out by the Colorado River in just the past 6 million years.
Laura Crossey/University of New Mexico
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About 6 million years ago, a new mineral analysis suggests, a mighty river zigzagging across the Colorado plateau may have found its way into older gorges, greatly enlarging them to create the West's most spectacular canyon. Still, some geologists aren't sold.
With new construction in the background, President Obama spoke about manufacturing and jobs during a visit to Intel's Ocotillo facility, Jan. 25, 2012, in Chandler, Ariz.
Ross D. Franklin/AP
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Amanda Gerety, a staff nurse at Boston Medical Center, checks monitors that track patients' vital signs. Fewer beeps means crisis warnings are easier to hear, she says.
Richard Knox/NPR
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Alice Snyder, with her parents Mary and Ryan, during a checkup with Dr. John Herzenberg, who treated her clubfoot without surgery.
Jenny Gold/Kaiser Health News
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Outgoing Federal Reserve Chairman Ben Bernanke spoke about the Federal Reserve's first and next century on Thursday at the Brookings Institution in Washington.
Manuel Balce Ceneta/AP
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The eastern Grand Canyon was about half-carved (to the level of the red cliffs above the hiker) from 15 million to 25 million years ago, an analysis published Sunday suggests. But the inner gorge was likely scooped out by the Colorado River in just the past 6 million years.
Laura Crossey/University of New Mexico
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Daft Punk won the Grammy for Album of the Year for Random Access Memories and for Record of the Year for "Get Lucky."
Frederic J. Brown/AFP/Getty Images
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