OUTER TRENCH SWELL Meaning and
Definition
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Outer trench swell refers to a geological feature that is found in some subduction zones. It is characterized by a broad, elevated region located on the outer edge of an oceanic trench. This trench is formed when one tectonic plate is subducted, or forced beneath another plate, at a convergent plate boundary.
The outer trench swell stands out due to its distinct topography. It is a swelling or bulging up of the seafloor located just outside the trench. This uplifted region is often several hundred kilometers wide and can extend for thousands of kilometers parallel to the trench. It typically rises several kilometers above the surrounding seafloor.
The formation of an outer trench swell is attributed to dynamic processes occurring at the subduction zone. It is believed to be caused by the influx of magma from the subducting plate that rises up and accumulates beneath the overriding plate. This accumulation leads to the uplift and swelling observed in the outer trench swell.
Outer trench swells play a significant role in shaping the Earth's crust and influencing the surrounding tectonic activity. They are known to affect the distribution of earthquakes and volcanic activity in subduction zones. Additionally, outer trench swells have implications on oceanic circulation patterns and can influence the development of marine ecosystems.
