Arizona's Grand Canyon
Arizona's magnificent Grand Canyon made the news headlines twice last week. First because of the decision to flood it with billions of gallons of water, to try restore the Canyon's natural habitat and the second time because of a new study that suggests that the Canyon is a lot older than we think.
Last Wednesday, officials started a three-day process to create a man-made flood inside the Canyon. Water from Lake Powell, above the Glen Canyon Dam gushed in at the rate of more than 300,000 gallons per second, causing the water level to rise as high as 15 feet in certain areas. The purpose of the man-made flood is to allow the sediment (sand and rocks) that are currently blocked by the dam to flow back freely into the canyon. This in turn will help rebuild sandbars that are essential for the native plants and marine life to survive. This is the third time the Grand Canyon is being flooded - the last two attempts in 1996 and 2004 were not very successful because the first time there was too much water and in 2004, there was not enough sediment. Officials are hoping to get the right balance this time.
How old is the Grand Canyon?
A new study released by three geologists, claims that the Grand Canyon is about 17 million years old, not the 5 or 6 million years currently estimated by scientists. Victor Polyak, Carol Hill and Yemane Asmerom came to this conclusion after going into various caves at the top of high cliffs and taking samples of mineral deposits in those caves. However, they conclude that 17 million years ago, the canyon was not as big and it is only in the last 5-6 million years that it has grown to its current size, thanks to erosion. Not all scientists are convinced this is true so the debate continues.....