What is the difference between the transition zones of the Pacific and Atlantic oceans?
Transition zones in the oceans are the places of boundaries where adjacent bottom relief features sharply contrast. For example, a flat bottom slides into a steep cliff, or vice versa, seamounts rise sharply. In turn, the zones are divided into areas that are characterized by island arcs, basins of marginal seas and deep-sea trenches.
Transitional Zones and Regions of the Pacific
These zones in the ocean stretch from the edges of the continents to the tallasocraton (tectonic floor of the ocean) and there are only 10 of them. The deepest depressions and trenches will be:
- Japanese depression.
- The Mariana Trench.
- Indonesian-Philippine depression.
- Aleutian Trench.
All western transitional areas are characterized by deep trenches and the presence of marginal seas, and island arcs act as their limiters. In addition, a feature of such transitions is their two-stage nature, where the young islands form the first separation boundary, and the older islands, in some of which the continental land is also present, the second. The eastern regions are expressed only by deep-water trenches – the Peruvian-Chilean and Central American ones, and comparatively young seamounts act as limiters. All transitional regions and zones in the Pacific Ocean are characterized by high seismic activity and volcanism. By their location, these volcanoes form the Pacific Ring of Fire – the center of modern underwater oceanic earthquakes.
Atlantic Ocean: Transition Zones
In this ocean, such zones are expressed by only two regions – the Antilles (Caribbean) and Mediterranean. The island arcs here for the most part do not act as limiters due to their young age and have a loop-like shape. The grooves are located not only on the inside, but also on the outside of the arcs. The bottom relief is complicated by the presence of many basins, sometimes very large (Yucatan, Grenada), the depth of which can reach 5000 m. The regions differ in age and complexity of the device: the Caribbean is considered younger and more complex, and the Mediterranean is older, because it also contains the continental crust.
