Washington, Apr 12 (UNI) Once the dinosaurs used to roam and stroll the regions of the steep-sided gorges called Grand Canyon carved by the Colorado river in the United States, claims researchers.
New geological evidence indicates the Grand Canyon may be so old that dinosaurs once lumbered along its rim, according to a study by researchers from the University of Colorado at Boulder and the California Institute of Technology.
The geologists have concluded with aid of radiometric dating technology to show the Grand Canyon may have formed more than 55 million years ago, Science Daily reported.
These findings have pushed ahead the date of the origin of the Colorado river gorges by 40-50 million years.
The researchers gathered evidence from rocks in the canyon and on surrounding plateaus that were deposited near sea level several hundred million years ago before the region uplifted and eroded to form the canyon.
''As rocks moved to the surface in the Grand Canyon region, they cooled off,'' Prof. Rebecca Flowers said.
''The cooling history of the rocks allowed us to reconstruct the ancient topography, telling us the Grand Canyon has an older prehistory than many had thought,'' he said.
The team believes an ancestral Grand Canyon developed in its eastern section about 55 million years ago, later linking with other segments that had evolved separately.
''It's a complicated picture because different segments of the canyon appear to have evolved at different times and subsequently were integrated,'' Prof. Flowers said.
Grand Canyon gorges are largely contained within the Grand Canyon National Park one of the first national parks in the United States.
US President Theodore Roosevelt was a major proponent of preservation of the Grand Canyon area, and visited on numerous occasions to hunt and enjoy the scenery.
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