The Grand Canyon is 446 km long, up to 29 km wide, and 1.6 km deep. The walls of the Grand Canyon are composed of nearly 40 different rock layers that represent about 1 billion years of Earth’s history. The rocks at the bottom of the canyon are metamorphic rocks formed 1.75 billion years ago. New sediments were deposited on top of those rocks, and mountain-building events around 755 million years ago tilted and lifted the new rocks. The total sandstone, shale, and limestone layers were deposited between 1,000 and 250 million years ago to form a rock sequence up to 1,525 m thick. WRITE YOUR ANSWER ON THE LINEIDENTIFY two geologic processes occurring in the Grand Canyon today that also contributed to the formation of the rocks that make up the Grand Canyon’s walls.

Geologists call the process of canyon formation downcutting. Downcutting occurs as a river carves out a canyon or valley, cutting down into the earth and eroding away rock.

Down cutting happens during flooding. When large amounts of water are moved through a river channel, large rocks and boulders are carried too. These rocks act like chisels, chipping off pieces of the riverbed as they bounce along.

Explanation:

that would be called plucking : )

explanation:

''plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". as a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock."