Mariana Trench: It Doesn't Get Any Deeper

Submarine Ring of Fire 2006 Exploration, NOAA Vents Program

Small chimneys on the floor of Nikko caldera in the Mariana Trench.

The northern Mariana arc submarine volcanoes. The Mariana Trench, located south of Japan and east of the Philippines, is the deepest part of the world's oceans, Marine scientists estimate its depth at around 36,201 feet.

Producer James Cameron is building a manned submersible that will film in the Mariana Trench. The footage may wind up used in the sequel to "Avatar."

With its two-man crew of Don Walsh and Jacques Piccard, the Trieste reached the deepest point in the Mariana Trench - some 35,797 feet below the surface on January 23, 1960. It remains the only manned vessel to achieve that feat.

Fryer and Hussong (Proceedings of the Deep Sea Drilling Project

3-D sketch shows a cross-section of the Mariana Arc with some of its main structures and features. How deep is the trench? Consider this: If you dropped Mount Everest, the highest mountain on Earth, into the deepest part of the Mariana Trench, it would still be nearly 7,000 feet under water.

Underwater bubbles, probably carbon dioxide, released from a volcano in the Mariana Trench. Yellow parts of the plume are believed to contain droplets of molten sulfur.

Liquid carbon dioxide bubbles rise from the sea floor.

Scientists study the effect of lowered pH from volcanic CO2 emission on mussel communities that live on rocky ridges near acid-producing vents.

Tonguefish at the edge of the Sulfur Cauldron at Daikoku volcano.

A remotely operated vehicle photographed a tonguefish swimming in front of the camera (in the foreground).

Marine biologists use hydrothermal fluid and particle sampler to sample hydrothermal water and microbes at NW Eifuku on the remotely operated vehicle.

Shells of dead mussels dissolve very quickly, but the community maintains a high density. Squat lobster and shrimp are also abundant at NW Eifuku.

One of the craters at the summit of Daikoku is more than 325 ft deep and about 260 ft in diameter. A large plume of white fluid slowly rises out of it

A collage of some of the dead animals on the sea floor, killed by volcanic plume which contained high amounts of sulfur. The top petri dish holds a squid and a open water shrimp - these are not vent species. The bottom images are the dead animals (shrimp, fish, and squid) on the sea floor

Called Brimstone Pit, the pressure of 1,837 feet of water over the site reduces the power of the explosive bursts. Also, the water quickly slows down the rocks and ash that are violently thrown out of the vent.

Close up of the front edge of lava flow. Note the large pieces of sulfur in the foreground, which have enveloped pieces of lava.

Newly-formed lava near Brimstone Pit

Verena Tunnicliffe. University of Victoria, Canada

A species of shrimp found on the NW Rota-1 volcano has also been identified at the Loihi seamount, located off the coast of Hawaii

Don't get too close. This pond of molten sulfur was discovered at Daikoku volcano; the temperature of the molten sulfur was measured at 369 degrees Fahrenheit.

Inactive ornamented sulfur chimneys. This one is sitting on end in the middle of a huge field of tubeworms.

A pot of molten sulfur bubbles out of the sea floor in this area of sheets of sulfur crust. The red laser beam dots are about 4 inches apart.

Tubeworm "bushes" hug the edge of the sulfur crust, which is covered with crabs and flatfish.

The sea floor in the summit crater is mostly covered by lush bushes of tubeworms in association with white crabs, flatfish, and shrimps.

Tonguefish and crabs, which seems to thrive around the hydrothermal vents of the Mariana volcanoes, cover the sea floor in some areas.