Additionally, the material can also form when a glacier brushes against the mountain slope, causing material to be scraped off or plucked off. Good examples of this are seen in Svalbard, Norway, but they are a common occurrence in glacial regions. This is a form of paraglacial activity. Once the material is deposited, it can be transported alongside the glacier. When the glacier melts, the long line of material is deposited, and only the lateral moraine remains.
Lateral and medial moraines consist of glacially-transported rock and debris. They form on the sides of glaciers lateral moraines or at the boundary between two tributary glaciers medial moraines. Either way, they often mark the edges of an ice body. Lateral moraines are sharp-crested piles of glacially-transported rocks and debris that are dropped by the ice as it melts.
They form only in the ablation zone of a glacier where more ice is melting than is accumulating as snow each year. This makes them good indicators of where the line between the accumulation zone and the ablation zone—the equilibrium line—occurred on past glaciers.
They often remain on the landscape long after glacier retreat and are frequently contiguous with terminal moraines. Medial moraines form where two tributary glaciers come together. Scientists study terminal moraines to see where the glacier flowed and how quickly it moved. If a mineral that is unique to one part of a landscape is present in a terminal moraine, geologists know the glacier must have flowed through that area.
Moraines of Kilimanjaro Moraine landscapes are found all over the world and are still being formed. Meanwhile, the melting snows on Tanzania's Mount Kilimanjaro are leaving fresh moraine in equatorial Africa.
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Erosion is the process where rocks are broken down by natural forces such as wind or water. There are two main types of erosion: chemical and physical. In physical erosion, the rock breaks down but its chemical composition remains the same, such as during a landslide or bioerosion, when plants take root and crack rocks.
Explore the process of erosion with this collection of resources. Weathering is the process of the weakening and breakdown of rocks, metals, and manmade objects. There are two main types of weathering: chemical and physical. An example of chemical weathering is acid rain. Caused mostly by the burning of fossil fuels, acid rain is a form of precipitation with high levels of sulfuric acid, which can cause erosion in the materials in which it comes in contact.
An example of physical weathering is wind blowing across the desert playas. This process causes rocks to form a specific pyramid-like shape and they are called ventifacts. Select from these resources to teach about the process of weathering in your classroom.
Glaciers appear on almost every continent.
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