US Grand Canyon, one among the seven natural wonders of world, is in reality 65 million years old than what was thought, revealed a study conducted by the University of Colorado Boulder. This means that Grand Canyon might have been there at the time of dinosaurs as well. In the previous estimates of the age of Grand Canyon, it was found that it was 5-6 million years old depending upon the age of gravel-washed downstream by the Colorado River.
Researchers nevertheless believe that it was created around 70 million years ago when dinosaurs had existed on Earth. The researchers made use of radioactive decay as well as thermal dating in order to find out the age of Grand Canyon. In the study, the radioactive decay of thorium as well as uranium atoms was exploited into the helium atoms in phosphate mineral called apatite. The helium atoms remained locked inside the apatite grains when they cooled and contracted to surface when Grand Canyon was carved. Hotness of the apatite determined that fewer helium atoms were there within it, which enabled researchers to find out thermal history of this area.
The temperature variations at the shallow levels under the surface of Earth are influenced by the topography and this in turn enabled the team of researchers to find out about the important natural excavation of this wonder of the world. The research found out that Grand Canyon was carved to around some hundred metres of the modern depth around 70 million years back.