Transcript Mariana Trench

The World’s Deepest Mystery
BY: ANANYA ARAVINDAN
WHAT MAKES THE MARIANAS
TRENCH SO UNEXPLORED?
 Extreme cold
Highly pressurized
Total darkness
Currents
No Oxygen
Floor has hydrothermal (hot water) vents
and the temperature around the vents can
reach 300◦C
CLIMATE AND LOCATION
The Marianas Trench is located in the western Pacific,
east of the Philippines. It is a crescent shaped scar in
the earth’s crust (over 1,500 miles). The relatively warm
water of the Pacific Ocean stretches to the depths of
500 to 1,000 feet. After that the water forms something
known as thermocline in which the water temperature
drops rapidly. The thickness of this varies anywhere
from 1,000 to 3,000 feet. After that the water cools
more slowly. At the bottom of the Marianas Trench the
water temperature is anywhere between 1-4◦C, just
above freezing.
WHY IS EXPLORING THE MARIANAS
TRENCH IMPORTANT?
The ocean area is much of the biosphere, yet we know more about
the surface of the moon and Mars than we do about the depths of
our own world.
There are many important discoveries waiting to be found in the
Marianas Trench. For example in 1977 we discovered
hydrothermal vents and their organisms which revolutionized our
ideas about energy sources and the adaptability of life.
Scientists have found new species such as shrimp-like amphipods,
and strange, translucent animals called holothurians . Scientists
are particularly interested is microorganisms as they may lead to
breakthroughs in biomedicine and biotechnology. Also they might
shed light on the emergence of life on Earth.
Additionally, studying rocks from ocean trenches can help
understand the earthquakes that cause the powerful and
devastating tsunamis around the Pacific Rim.
JOURNEY DOWN DEEP
On March 26, 2012 James Cameron piloted the Deepsea
Challenger submersible to the Challenger Deep of the
Marianas Trench. It was the world’s first extensive scientific
exploration in a manned submersible.
The Deepsea Challenger was custom built for this adventure
and he was the sole occupant. The pilot sphere was so small
that James Cameron could not even extend his arms. While
he was there he filmed footage for a feature length
documentary and he also collected samples for research.
This journey was part of the Deepsea Challenge which is
dedicated to advancing the world’s knowledge about our
deepest wonders.
DEEPSEA
CHALLENGER
TOOLS AND TECHNOLOGY
There have been advances in observational equipment like fiber optic
LED lights and low light cameras which have increased our
understanding of deep sea creatures in their habitat. These
observational devices may be attached to permanent sub-sea
stations which are connected to land via fiber optic cables or on
lander devices which are dropped to the sea floor, then picked up
later.
There are also ROV’s (Remotely Operated Vehicle) which have video
and still cameras attached and mechanical arms for picking
specimens up. Then there are AUV’S (Autonomous Underwater
Vehicle) which also have cameras but are preprogrammed to
operate without cables. USA’s Nereus was the first unmanned
submarine to reach the deepest trenches. This submarine could
switch from ROV mode to AUV mode!
Finally there are manned deep-sea submersibles. Alvin was one of
these and he was built in 1964 in America and was used
extensively. It had mechanical arms, cameras, could hold3 people,
and went on more than 400 dives reaching a maximum depth of
4,500 meters.
HOW HAS CANADA HELPED?
Though Canada has not directly helped build the tools to
explore the Marianas Trench we have helped build tools to
explore other areas of the ocean. The ISE (International
Submarine Engineering) company has recently helped build
some AUV’s to explore underneath the Arctic ice, north of
Canada. One of those is the Arctic Explorer which is a
derivative of the successful Explorer AUV that was first
designed in 2001. ISE has built two Arctic Explorers for
Natural Resources Canada to map the sea floor underneath
the Arctic ice. In April 2010, one of these vehicles completed
over 1000 km of under-ice survey, mapping the sea floor
during 10 days of continuous underwater operation.
Also ISE has built AUV’s for the Memorial University of
Newfoundland in Canada and University of Bremen in
Germany. They also built an Explorer for the National Oceanic
and Atmospheric Agency in the USA.
WILL IT LAST?
Even though the Marianas Trench is rather unexplored it
is still in danger of pollution. On James Cameron’s
recent adventure to the Challenger Deep, his deep-sea
submersible had a hydraulic fluid leak.
Hydraulic fluids are liquids that are used as the motive
medium in hydraulic machinery and equipment.
When Hydraulic fluid is heated to it’s flash point,
sprayed, or vaporized it becomes highly hazardous.
This could very well happen at the Challenger Deep as
there are thermal vents on the sea floor which can
reach a high of 300◦ C.
WILL IT LAST?
However because of the current interest in protecting the
environment, scientists have developed biobased and
biodegradable hydraulic fluids. These biobased fluids help to
minimize pollution in the case of an oil leak. In order to explore
the Marianas Trench responsibly and help lessen the risk of
pollution we can use these biobased fluids instead of the regular
ones.
Another threat to the environment is the studying of microbes. It
has proven difficult because it’s nearly impossible to bring up the
sediment without raising its temperature and de-pressurizing it,
which can kill organisms adapted to such conditions. To
overcome this obstacle, scientists from Germany and Japan
devised instruments to study the organisms in their place at the
sea floor.
FUN FACTS
 The Marians Trench is 36,070 feet deep
 If Mount Everest was dropped into the Marianas
Trench, it would still be a mile under water
 The deepest point is called the Challenger Deep
 The pressure at the Challenger Deep is 11,318 tons per
square meter (that’s the equivalent of one person
trying to hold up 50 jumbo jets)
 More people have been on the moon than at the
bottom of the Marianas Trench
ard to reach
H
O
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P
ver 36,00 feet deep
ater pressure
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xcitement
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Marianas Trench
THANKS FOR
WATCHING!