EarthMapped Ocean trenches
World map of ocean trenches and their deepest pointsChallenger DeepHorizon DeepBrownson DeepMeteor DeepSouth Sandwich TrenchJava Trench

Ocean Trenches Map

Ocean trenches are the deepest parts of the sea floor. They form where one tectonic plate sinks under another. Most lie around the Pacific, and the deepest is the Mariana Trench at about 10,924 m.

  • Ocean trench. A long, narrow trough in the sea floor, 8 to 10 km deep, where one plate bends down under another. Source

Data source: Bongiovanni, Stewart and Jamieson (2022), Five Deeps Expedition, CC BY 4.0. Download: Deepest points CSV .

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What the map shows

Thick blue lines are subduction zones from the PB2002 plate model, where one plate sinks under another Subduction zone. Where one plate sinks under another and back into the mantle, usually marked by a deep ocean trench. Source . A trench Ocean trench. A long, narrow trough in the sea floor, 8 to 10 km deep, where one plate bends down under another. Source runs along each of them on the sea floor. The dark patches are sea floor deeper than 6,000 m from the Natural Earth depth polygons, and they sit along the same lines. Dots mark the deepest measured point of each ocean.

Key facts

  1. Ocean trenches are 8 to 10 km deep. They form where one plate is pulled down under another and sinks into the mantle. USGS, Understanding plate motions
  2. The deepest point measured is the Challenger Deep in the Mariana Trench: 10,924 ±15 m. Bongiovanni, Stewart and Jamieson (2022), Geoscience Data Journal 9(1)
  3. The Five Deeps Expedition found the deepest point of every ocean. In the Pacific, Atlantic, Southern and Indian oceans it lies in a trench. Only the Arctic's deepest point, the Molloy Hole, is not in a trench. Bongiovanni, Stewart and Jamieson (2022), Geoscience Data Journal 9(1)
  4. PB2002 maps 51,309 km of subduction zone. The trenches on this map follow those lines. PB2002 plate model, Bird (2003), converted by Hugo Ahlenius, Nordpil
  5. Sea floor deeper than 6,000 m covers about 2,391,125 km² on the Natural Earth depth polygons, 0.66% of the ocean.

Deepest points and their trenches

Depths from the Five Deeps Expedition sonar survey. For a point in a trench, the plate pair and convergence rate come from the nearest PB2002 subduction step. Sort by any column.

Deepest measured points of the oceans
DeepFeatureOceanDepth (m)PositionPlates (PB2002)Convergence (cm/yr)
Challenger Deep Mariana Trench Pacific 10,924 ±15 11°N, 142°E Philippine Sea and Pacific 1.9
Horizon Deep Tonga Trench Pacific 10,816 ±16 23°S, 175°W (approx.) Tonga and Pacific 10.9
Brownson Deep Puerto Rico Trench Atlantic 8,378 ±5 20°N, 68°W no PB2002 subduction step within 300 km
Meteor Deep South Sandwich Trench Atlantic 8,265 ±13 55°S, 26°W (approx.) Sandwich and South American 4.1
Unnamed deep South Sandwich Trench Southern 7,432 ±13 60°S, 25°W Sandwich and South American 4.5
Unnamed deep Java Trench Indian 7,187 ±13 11°S, 118°E Sunda and Australian 6.6
Dordrecht Deep Diamantina Fracture Zone Indian 7,019 ±17 34°S, 102°E (approx.) not a trench
Molloy Hole Sea floor between Greenland and Svalbard Arctic 5,551 ±14 79°N, 3°E not a trench

Data source: Bongiovanni, Stewart and Jamieson (2022), Five Deeps Expedition, CC BY 4.0. Download: Deepest points CSV .

Data source: PB2002 plate model, Bird (2003), converted by Hugo Ahlenius, Nordpil, ODC-By 1.0.

Zoom in on the deepest one on the Mariana Trench map, see the whole sea floor on the ocean floor map, or follow the sinking plates on the subduction zones map. The Pacific Plate sinks under most of them. All plates: tectonic plates.

Print this map Ocean currents worksheet. Label the currents and the five gyres, with an answer key

Glossary

Ocean trench
A long, narrow trough in the sea floor, 8 to 10 km deep, where one plate bends down under another. Source
Subduction zone
Where one plate sinks under another and back into the mantle, usually marked by a deep ocean trench. Source
Bathymetry
The study of the floors of the ocean, lakes and rivers: how deep the water is and the shape of the bottom. Source

All terms in the glossary

Ocean trenches FAQ

What is the deepest ocean trench?
The Mariana Trench in the western Pacific. Its deepest point, the Challenger Deep, was measured at 10,924 ±15 m. See the Mariana Trench map.
How do ocean trenches form?
Where two plates move toward each other, one is pulled down under the other and sinks into the mantle. The trench is the deep groove on the sea floor where it goes down. See the subduction zones map.
Why are most trenches around the Pacific?
Because subduction zones ring the Pacific, as the PB2002 lines on this map show, and trenches form along subduction zones. See the Pacific Plate.
What is the deepest point in the Atlantic?
The Brownson Deep in the Puerto Rico Trench, measured at 8,378 m.
What does the convergence column mean?
It is how fast the two plates close on each other at the nearest PB2002 subduction step, in centimeters per year. It is a model value for that point, not a measured trench rate.

Sources: USGS, Understanding plate motions; Bongiovanni, Stewart and Jamieson (2022), Geoscience Data Journal 9(1); Stewart and Jamieson (2019), Earth-Science Reviews 197.