fracture and deform. This movement also releases the pressure on the underlying hot rocks, causing them to begin melting. They confirm that the oceanic crust is everywhere younger than about 200,000,000 years and that the stratigraphic age determined by micropaleontology of the overlying oceanic sediments is close to the age of the oceanic crust calculated from the magnetic anomalies. As the crust subducts into the mantle it melts causing igneous activity below, magma to rise and therefore volcanoes erupt on the surface as a result. The ridge-crest earthquakes originate because of the tension created when the plates on either side move in opposite directions. An example of where landforms have been created at a different plate boundary, a destructive plate margin, is where two plates, the Nazca plate, an oceanic plate, and the South American plate, a continental plate, converge. Where subduction occurs along a continental edge, volcanism distorts the continental rocks, forming such mountain chains as the Andes. From this, a plume of magma rises to eat into the plate above the hotspot. Here two plates diverge or move away from each other, pushed apart by huge convection currents In the earths mantle. Org) The Andes: The Andes are a Mesozoic Tertiary organic belt of mountains along the Pacific Ring of Fire. Although there are situations where the two are not linked, ultimately the characteristics of the landform will have been influenced by some soft of tectonic movement.
The second boundary type occurs in areas where these ridges are offset. This is marked on the ocean surface by the presence of the Peru-Chilie trench. Earthquakes forming the third boundary are distributed more diffusely but include all of the worlds deep earthquakes (i.e., those originating at depths greater than 145 km) and are associated with extremely narrow zones in which the ocean floor descends below its normal depth. To the west, south of the Valle dAosta, the Southern Alps form a huge monocline, up until the point that mantle material of the Apulian plate crops out in what is called the Ivrea zone.
There are no continental rocks more than 4 billion years old, possibly because the lithosphere was thin and was recycled without generating continental rocks. Finally, collision plate boundries. There are three main types of mountains: volcanic, fold, and block. The lava cools, solidifies and forms a chain of volcanic mountains thousands of miles something no one knows about me essay long down the middle of the ocean. These can be eroded to have flat tops called guyots.
Literary analysis essay frankenstein, Factors affecting human growth and development essay,