TRENCHES AROUND THE WORLD
Firstly How trenches are formed:
At trench Ocean floor destroyed melted in mantle
Oceanic crust heavier than continental crust
Ocean floor act like conveyor belt
Ocean floor cyclic process 300 ml yrs
Some Important trenches around world:
Name Location Depth (metres) Depth (feet) Depth
1 Mariana Trench Pacific Ocean 10,911 35,797 6.78
2 Tonga Trench Pacific Ocean 10,882 35,702 6.76
3 Philippine Trench Pacific Ocean 10,540 34 580 6.54
4 Kuril-Kamchatka Trench Pacific Ocean 10,500 34,449 6.52
5 Kermadec Trench Pacific Ocean 10,047 32,963 6.24
6 Japan Trench Pacific Ocean 9,000 29,527 5.59
7 Puerto Rico Trench Atlantic Ocean 8,605 28,232 5.35
8 Yap Trench Pacific Ocean 8,527 27,976 5.30
9 South Sandwich Trench Atlantic Ocean 8,428 27,651 5.24
10 Peru-Chile Trench Pacific Ocean 8,065 26,456 5.01
11 Diamantina Trench Indian Ocean 8,047 26,401 5.00
12 Romanche Trench Atlantic Ocean 7,760 25,460 4.82
13 Cayman Trough Caribbean Sea 7,686 25,238 4.78
14 Aleutian Trench Pacific Ocean 7,679 25,194 4.77
15 Java Trench Indian Ocean 7,455 24,460 4.63
15 Middle America Trench Pacific Ocean 6,669 21,880 4.14
16 Eurasian Basin Arctic Ocean 5,450 17,881 3.39
1. Mariana Trench: Please note Guam is US Trust Territory of Pacific Island
*Above Equator below Tropic of Cancer *Challenger deep
2. Tonga Trench:
The Tonga Trench is an oceanic trench located in the South Pacific Ocean. It is 10,882 metres (35,702
ft) deep at its deepest point, known as the Horizon Deep.
3. Philippines Trench: The Philippine Trench (also Philippine Deep, Mindanao Trench, and Mindanao
Deep) is a submarine trench to the east of the Philippines.
* 3rd Deepest after Challenger (Mariana),Horizon (Tonga)
4. The KurilKamchatka Trench or Kuril Trench (Russian: - , Kurilo-
Kamchatkii Zhyolob) is an oceanic trench in the northwest Pacific Ocean. It lies off the southeast
coast of Kamchatka and parallels the Kuril Island chain to meet the Japan Trench east of Hokkaido. It
extends from a triple junction with the Ulakhan Fault and the Aleutian Trench near the Commander
Islands, Russia, in the northeast, to the intersection with the Japan Trench in the southwest.The
trench formed as a result of the subduction zone, which formed in the late Cretaceous, that created
the Kuril island arc as well as the Kamchatka volcanic arc. The Pacific Plate is being subducted
beneath the Okhotsk Plate along the trench, resulting in intense volcanism.
5. The Kermadec Trench is one of Earth's deepest oceanic trenches, reaching a depth of 10,047
metres (32,963 ft). Formed by the subduction of the Pacific Plate under the Indo-Australian Plate, it
runs over a thousand kilometres parallel with and to the east of the Kermadec Ridge and island arc,
from near the northeastern tip of New Zealand's North Island to the trench's junction with the
Louisville seamount chain northeast of Monowai Seamount. The Tonga Trench marks the
continuation of subduction beyond this point. Subduction south of the Kermadec Trench is marked
by the shallower Hikurangi Trench.
6. Japan Trench
The Japan Trench is a part of the Pacific Ring of Fire, in the floor of the northern Pacific Ocean off
northeast Japan. This is an oceanic trench.It extends from the Kuril Islands to the Bonin Islands and is
9,000 metres (29,500 ft) at its deepest. It is an extension of the Kuril -Kamchatka Trench to the north
and the Izu-Ogasawara Trench to its south with a length of 800 km (500 mi).
This trench is created when the oceanic Pacific plate subducts beneath the continental Okhotsk
Plate. The subduction process causes bending of the downgoing plate, creating a deep-sea trench.
Since 1973 the Japan Trench subduction zone has hosted nine events of magnitude 7 or greater.
7. Yap Trench:
The Yap Trench is an oceanic trench near Yap Island in the western Pacific Ocean. The trench forms
the part of the Pacific Ring of Fire between the Palau Islands and the Mariana Trench. It is 650
kilometres (400 mi) long and 8,527 metres (27,976 ft) deep at its deepest point.
8. The PeruChile Trench, also known as the Atacama Trench, is an oceanic trench in the eastern Pacific Ocean, about 160 kilometres (100 mi) off the coast of Peru and Chile. It reaches a maximum depth of 8,065 metres (26,460 ft) below sea level in Richards Deep and is approximately 5,900 kilometres (3,666 mi) long; its mean width is 64 kilometres (40 mi) and it covers an expanse of some 590,000 square kilometres (228,000 mi).The trench delineates the boundary between the subducting Nazca Plate and the overriding South American Plate.
9. Aleutian Trench
The Aleutian Trench (or Aleutian Trough) is an oceanic trench along a convergent plate boundary
which runs along the southern coastline of Alaska and the Aleutian islands. The trench extends for
3,400 km from a triple junction in the west with the Ulakhan Fault and the northern end of the
Kuril-Kamchatka Trench, to a junction with the northern end of the Queen Charlotte Fault system
in the east. It is classified as a "marginal trench" in the east as it runs along the margin of the
continent. The subduction along the trench gives rise to the Aleutian arc, a volcanic island arc,
where it runs through the open sea west of the Alaska Peninsula. As a convergent plate boundary,
the trench forms part of the boundary between two tectonic plates. Here, the Pacific Plate is being
subducted under the North American Plate at a dip angle of nearly 45 degrees. The rate of closure
is ~3in. (8 cm) per year.
10. Middle America Trench: submarine depression in the Pacific Ocean off the western coast of
Central America. Extending northwest-southeast for more than 1,700 miles (2,750 km) from central
Mexico to Costa Rica, the trench reaches a maximum depth of 21,880 feet (6,669 metres) and covers
a total area of 37,000 square miles (96,000 square km). The shallower northern section of the trench
tends to curve along the coast of Mexico, paralleling the break in the continental shelf, while the
deeper southern section follows a more linear course. The southern section of the trench is usually
associated with active volcanism on land, as, for example, the eruption in 1982 of El Chichn volcano
in southern Mexico; the trench floor in this area is irregular.
11. Puerto Rico Trench, submarine depression in the North Atlantic Ocean, roughly parallel to the northern coast of the island of Puerto Rico and lying about 75 miles (120 km) to the north. The Puerto Rico Trench is about 1,090 miles (1,750 km) long and 60 miles (100 km) wide. The deepest point in the Atlantic Ocean, the Milwaukee Depth, lies at a depth of 27,493 feet (8,380 m) in the western end of the trench, about 100 miles (160 km) northwest of Puerto Rico. The origin of the trench can be traced back to the beginning of the Cenozoic Era (about 65 million years ago). The Puerto Rico Trench appears to be part of a complex system of sinistral strike-slip faults in the north Caribbean; the trench seems to have been open continuously for about 70 million years. It is partially filled with sediments.
12. The South Sandwich Trench is a deep arcuate trench in the South Atlantic Ocean lying 100 km
to the east of the South Sandwich Islands. The trench is produced by the subduction of the
southernmost portion of the South American Plate beneath the small South Sandwich Plate. The
South Sandwich Islands constitute a volcanic island arc which results from this active subduction.
Mount Belinda on Montagu Island is an active volcano.It is the deepest trench of the Southern
Atlantic Ocean, and the second deepest of the Atlantic Ocean, after the Puerto Rico Trench.The
trench is 965 km long and has a maximum depth of 8,428 metres below sea level. This location, at
5540'S, 02555'W, is called Meteor Deep. It is 122 km northeast of Zavodovski Island.
13. Romanche Trench: The Romanche Trench, also called the Romanche Furrow or Romanche Gap,
is the third deepest of the major trenches of the Atlantic Ocean, after the Puerto Rico Trench and
the South Sandwich Trench. It bisects the Mid-Atlantic Ridge (MAR) just north of the equator at the
narrowest part of the Atlantic between Brazil and West Africa, extending from 2N to 2S and from
16W to 20W. The trench has been formed by the actions of the Romanche Fracture Zone, a
portion of which is an active transform boundary offsetting sections of the Mid-Atlantic Ridge
14. Diamantina Trench
The Diamantina Fracture Zone is an area of the south-eastern Indian Ocean seafloor. It has a range
of ridges and trenches. It lies to the south of the mideastern Indian Ocean features of
the Wharton Basin and Perth Basin, and to the south west of the Naturaliste Plateau
Being parallel to the Southeast Indian Ridge, Diamantina Fracture Zone is not a real fracture
zone in the sense of plate tectonics, but rather an escarpment, separating twooceanic plateaus
15. Java Trench/Sunda Trench
Java Trench, also called Sunda Double Trench, deep submarine depression in the eastern Indian
Oceanthat extends some 2,000 miles (3,200