Environmental Engineering Reference
In-Depth Information
Ocean basin
Continental margin
Continental rise
Ocean basin floor
Continental
Continental
slope
shelf
Abyssal
Oceanic
Trenches
Sea mounts
Plains
rises
Fig. 1.1
Components of the ocean basin (Mitra
2000a
)
Fig. 1.2
Diagrammatic sectional view of the ocean basin
around the continent of Antarctica. In the Paci
c
1:1000. They are formed due to even deposition
of sediments from the continental rise carried
down by the turbidity currents. Oceanic rises
refer to rather isolated areas, which are elevated
above the abyssal
Ocean,
nd trenches
located at the bottom of the continental slopes.
Oceanographers have studied that sediments
from the continental shelf are carried into the
deep ocean through the canyons present in the
continental slope. At the foot of the continental
slope, the suspended materials and sediments
settle out that slope gently towards the ocean
fl
it
is more common to
oor and are distributed spo-
radically on the ocean basin
fl
oor. They may vary
from low hills to mountains as high as 1,525 m.
The example of Bermuda rise is very prominent
in this context on which the Bermuda Islands are
formed. Seamounts are isolated peaks that rise
several
fl
oor. This region is basically the continental rise
and has a gradient between 1:50 and 1:800.
oor.
They are volcanic in origin and are found prin-
cipally in the vicinity of the fault zones. Some
seamounts show evidence of coral reefs and
surface erosion, suggesting that at one time they
were above the surface. Movements of the ocean
fl
thousand metres above the sea
fl
Ocean Basin Floor
The ocean basin
oor extends seaward from the
continental rise or the continental margins and
includes the abyssal plains, oceanic rises, sea-
mounts and trenches. Abyssal plains are found
at
fl
oor, the natural process of compaction that
volcanic material undergoes, subsidence due to
cooling of the ocean
the base of
the continental
rise and are
relatively
fl
at plains having a gradient less than
fl
oor, erosion, and the
