Question

The picture shows how the Grand Canyon looks now. But millions of years ago, this region was completely buried under Earth’s surface. The change that happened over the years was caused by .
a volcanic eruption
erosion
an earthquake
a metorite

Answer 1

The correct answer is option B, erosion

As per the stream capturing model, it was found that that the Colorado River flows through the Marble Canyon to the  Colorado River drainage. During its course of flow, the river took a south easterly direction and drains into the Rio Grande River. There had occurred one more drainage that cut the plateau in the west ward direction through the plateau. Again the erosion in the hearward side cut the  Colorado Plateau in the eastward direction. Later on the area to the southeast was uplifted to allow the Colorado River to flow into the basin.