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Ancient rocks from Wyoming's Teton range are due to continental collisions that go back to 2.68 billion years ago, according to a team of University of Wyoming scientists. Examining the plate tectonics in what is today called Western Wyoming, the scientists hypothesise that it happened just like what created the Himalayas almost 40 million years ago.

The study examines rocks in the Tetons that are probably the oldest remnants of continent-continent collisions.

"While the Himalayas are the prime example of continent-continent collisions that take place due to plate tectonic motion today, our work suggests plate tectonics operated far, far back into the geologic past," Carol Frost, lead author of the paper, said in a press release.

Analysing the ancient granite exposed in the northern Teton Range, the scientists compared them to other rocks in the Himalayas, created while magma was produced through decompression melting. This happens when there is a collision between a couple of continental plates. Once the thick crust goes under gravitational forces, the deeper crust moves towards the top, leading to melting.

Even though the Tetons constitute a young mountain range created by an "uplift" on the Teton Fault lines than 9 million years ago, the study shows that the exposed rocks comprise the oldest in North America.

Both the Teton granites and the Himalayas are similar, yet some differences are due to the composition of the continental crust in Wyoming 2.68 billion years ago. It, in fact, was composed of less potassium than the recent Himalayan crust.

The findings were published in Dec. 31,2015 issue of Geochimica et Cosmochimica Acta.