Plate Tectonism, Oceanic Ridges and Rises Coursework

Plate Tectonism, Oceanic extends and Rises - Coursework ExampleSimilarities and differences amid a Continental arc and island arc will be provided. In general, oceanic ridges is referring to a mountainous chain of juvenility basaltic rock at the active spreading center of an ocean (Garrison, 2010 116) whereas oceanic rises ar referring to a long, broad elevation which can be found at the bottom of the ocean. Oceanic ridges are sources of the new ocean floor where lithospheric domiciles diverge (ibid). A good example of oceanic ridges includes the Bowers Ridge and Shirshove Ridge which can be found in the Bering Sea close to Alaska, Kamchatka, and Siberia. There are significant differences between oceanic ridges and oceanic rises. Although often mistaken as one, oceanic rises often have a gentler topography as compared to oceanic ridges. Furthermore, oceanic rises also are not characterized by the presence of wide central gap valleys which are often found in oceanic ridges (Garr ison, 2010 116). In fact, oceanic ridges reach its widest when active. The two hypotheses that fit(p) the foundation for plate tectonism a.k.a. plate structure includes the continental drift and seafloor spreading. To understand the theory behind plate tectonics, it is important to take note of the following features (1) the Earths surface is composed of 7 intumescent crustal plates (i.e. African, North American, South American, Eurasian, Australian, Antarctic, and Pacific plates) (2) ocean floors continuously move in different directions (i.e. vertical and flat movements) (3) convection currents underneath the plates causes the movement of crustal plates and (4) heat that triggers convection currents is radioactively rooted in the Earths mantle.