All trenches
PacificSubduction trench
Mariana Trench
Western Pacific, east of the Mariana Islands
The deepest known point on Earth, formed where the Pacific Plate subducts beneath the Mariana Plate.
Max depth
10,935 m
Length
2,550 km
Deepest point
Challenger Deep
First explored
1960
Timeline
Exploration
- 1875HMS Challenger first sounds the trench.
- 1960Piccard and Walsh reach Challenger Deep in the bathyscaphe Trieste.
- 2012James Cameron completes a solo dive in Deepsea Challenger.
- 2019Victor Vescovo makes repeated dives in DSV Limiting Factor.
Abyssal fauna
Life at pressure
Mariana snailfishXenophyophoresGiant amphipodsHolothuriansForaminifera
Life survives pressures over 1,000 times surface level, feeding on marine snow drifting from above.
Science
Scientific facts
- Pressure at the bottom exceeds 1,070 bar.
- Water temperature at the floor is about 1-4 °C.
- Microplastics have been found even at Challenger Deep.
Seafloor geology
Rock & structure
- Basalt and serpentinite exposed on the inner wall
- Pelagic clays and radiolarian ooze on the floor
- Serpentinite mud volcanoes on the forearc