ConstructiveDestructive Deposition Forces Forces Weathering Erosion 100 100 100 100 100 200 200 200 200 200 300 300 300 300 300 400 400 400 400 400 500 500 500 500 500 Water, wind, ice & growing plants. What is weathering? The minerals in rocks are changed or dissolved away. What is chemical weathering? Rocks are broken into smaller pieces and the minerals remain the same. What is mechanical weathering? This causes rocks to crack resulting in weathering. What is freezing water? Temperature changes, frost action, root action & animal activity. What are the four main causes of weathering? Carrying away of weathered materials. What is erosion? Glaciers, wind.. What are two agents of erosion? Glacier What is a moving river of ice? Sediment What are tiny pieces of broken down rock? What is the greatest agent of erosion? What is moving water? Pieces of eroded rock are dropped into another place. What is deposition? Tiny pieces of broken down rock. What is sediment? New land where sediment is dropped at the mouth of river . What is a delta? As it melts and shrinks, new materials are deposited. What is a glacier? In addition to water, new land is built as this deposits materials. What is wind? This process helps to build up the earth’s landforms. What are constructive forces? These landforms were caused by the very slow movement of the earth’s crust. What are mountains? This type of mountain is created on fault lines. What is a fault block mountain? This landform is created when land is squeezed together. What are fold mountains? Besides mountains, these are the main type of constructive force. What are volcanoes? These forces tear down the earth’s landforms. What are destructive forces? These scrape the Earth’s surface and act slowly to wear it away. What is a glacier? When the Earth’s plates collide, these occur. What is an earthquake? These two forces combine water and wind to change the Earth’s surface quickly. What are tornadoes and hurricanes? This force, combined with rapidly moving water, causes landslides. What is gravity?