Geological weathering occurs many ways. The main causes of weathering are water and wind. Water consistently running over a rock will eventually smooth that rock and wash away all of its rough spots. Wind blowing small particles like sand against another rock formation constantly will eventually lead to the breakdown of the rock into smaller particles that will continue this process elsewhere. Both of these contribute to a type of weathering, erosion that plagues coastlines, mountains, and highway planning agencies alike.
We witnessed weathering locally. The formation of South Mountain, a lone mountain, is due to weathering away of materials that are more resistant. We could see the process occurring when our class took a trip to hike at South Mountain. There were visible signs where they stream was slowly wearing away the rock and there was evidence of it. Large boulders could be found at the bottom of the mountain from where the rock had weakened and the boulders had broken away.
Another example of erosion and weathering is the continuous battle between the elements and tectonic plates of the Alps. An orogeny is a mountain forming event which is most commonly a continental plate colliding with an oceanic plate causing uplift in the landscape. Eventually the continental plate collides with another continental plate causing even more uplift. This process occurs over thousands of years but the end result is a mountain range. So in the Alps this process is constantly occurring so the mountains are growing every year. The ironic part is the fact that they are shrinking just as much.
The actual formation of the Alps between what is now the European plate and the African plate began 55 million years ago. Due to the placement of the plates today there is still a pressure forcing the two areas together so this process is still occurring today. Yet the Alps suffer heavy weathering every year from every angle.
Constant wind gusts and the flow of water are slowly wearing not only the tops of the mountains but the sides as well. But this does not happen to all mountain ranges. Some ranges such as the Himalayans are not stuck in this limbo but continue to rise each year. This is because the climate differences. For some reason the Alps are exposed to heavier weathering than other mountain ranges therefore they do not rise as steeply as them. Also, the continuation of the orogeny is slowly dying due to a shifting in the plates.
So it is possible to say that that rate of growth is equal to the rate of disappearance because as these particles are worn away and carried down the mountains there is an upwelling of fresh land from beneath the earth’s crust. This is an ongoing process that ensures that the Alps will be around for a while.