The Mariana Trench is the deepest part of the ocean located in the western Pacific Ocean near Japan. It contains Challenger Deep, which at over 11km deep is the lowest point on Earth. The trench formed as the Pacific Plate subducts under the Philippine Plate. It hosts unique ecosystems based on hydrothermal vents, with organisms adapted to survive in extreme cold and high pressure. While challenging to explore, several expeditions including Trieste (1960) and Nereus (2009) have visited Challenger Deep to study the unique geology and biology of the deepest known part of our planet.

1. Mariana Trench
Deepest trench in the world

2. Geology of Mariana Trench

3. Location
O Pacific Ocean
O East of Japan

4. Location
O Deepest trench in the
world
O Home to the deepest
part of the earth:
O Challenger Deep
O 11,033 meters
underwater
O Mt Everest: 2183 m

5. Location

6. Formation
O Oceanic-Oceanic Convergence
O Fast-moving Pacific Plate is subducted
under slower moving Philippine Plate

7. Formation
O Crust created from East Pacific Ridge
O Parallel to Mariana Trench
O Oceanic diverging plate

8. Formation
O New crust formed by the East Pacific
Ridge moved and is subducted at the
Mariana Trench
Mariana East Pacific Ridge
Trench

9. Computer Simulation of Mariana
Trench

10. Mariana Islands

11. Mariana
Islands

12. Geology of Mariana Islands
O Example of an island arc
O 15 Volcanic Islands that rise up from
ocean floor

13. Geology of Mariana Islands
O After millions of years, erupted lava
and volcanic debris pile up on the
ocean floor
O Causes a submarine volcano to rise
above sea level to form an island
volcano

14. Biology of Mariana Trench

15. Biology of Mariana Trench
O It is very cold and highly pressurized
O Hydrothermal (hot water) vents formed by
spreading tectonic plates release hydrogen
sulfide and other minerals
O consumed by the bacteria which are then
consumed by other microorganisms forming a
food chain
O Creatures from the deep show an incredible
resistance to temperature extremes by having
different proteins which are adapted for life
under these conditions( e.g. Crabs, Angler
Fish)

16. Biology of Mariana Trench
O Another interesting characteristic of these
deep sea creatures is their longevity
O many able to live for over a century
O Creatures seldom migrate and are slow to
develop

17. Exploration of Mariana
Trench

18. 1951: Challenger II
O Mariana Trench was first pinpointed
O Surveyed by British Survey Ship:
Challenger II

19. 1960: Trieste
O Exploration of deepest point (Challenger Deep)
O In U.S. Naval submarine
O Swiss Scientist Jacques Piccard and US Navy
Lt. Donald Walsh
O 20 min dive
O Confirmed trench to be the deepest point on
Earth

20. 1995: Kaiko
O Japanese Unmanned submersible
launched to explore Mariana Trench
O Went exploring a few times before lost at
sea in a typhoon (2003)

21. 2009: Nereus
O Submersible built by engineers at Woods
Hole Oceanographic Institution
O Collect rocks, animals, and water samples
and transmit high-quality video to the
surface through a hair-thin fiber-optic
cable.

22. 2012: DEEPSEA CHALLENGER
O A manned submersible – The second ever to
go to the Challenger Deep
O Undergoing sea trials beginning in March
2012
O By Director James Cameron (director of
TITANIC)

23. Thank you!!
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