On the sea floor, over 10,000 feet below us, lies a world very different from ours. The sheer depth of the sea floor ensures that few can unravel the mysteries it contains, as even catching a glimpse is no simple task! Nevertheless, man's desire to discover and explore our world is insatiable, and we have developed various ways to study and understand the world beneath us.



A quick peek into the depths of the sea reveals various tidbits of history here and there, as shown by the recent photographs released by the Irish National Seabed Survey, where scientists have been scanning under the waves since 1996. Most of the photographs are from deep water areas where the sonar-equipped ships can easily sail. The pictures show a 20 kilometer trench which is up to 30 meters deep, a possible indication of a geological fault.

There were also broad troughs carved into the sea floor during or soon after the last ice age, over 10,000 years ago. The sea floor sonar images also showed the large number of sunken German U-boats.

Even farther down, in the depths of the Pacific's Marianna Trench, over 36,000 feet below sea level, lives a thriving ecosystem never seen before by the likes of man. Scientists have long thought that in the depths of the ocean, there can be no life due to the extreme conditions. The immense pressure, the lack of oxygen, the complete darkness and low temperatures of the sea bed have always been thought to lead invariably to a sea floor ecosystem dominated by bacteria.

However, recent studies have demonstrated that even as bacteria dominate the upper ten centimeters of the sea floor, simple organisms known as Archaea take over below this level, comprising of up to 87 percent of the deep sea biosphere. Contrary to popular belief, despite the extreme conditions, there exists a thriving ecosystem in the deep sea floor, with an estimated 90 million tons of biomass. The researchers believe that roughly 200 million cubic kilometers of mud just below the sea floor is inhabited by microorganisms.

In order to reach this conclusion, the scientists researched various samples of silt collected from hundreds of meters below the Atlantic and Pacific sea floor. The samples came from the research expeditions by the Integrated Ocean Drilling Program. Following this groundbreaking discovery, the researchers, Drs. Inagaki and Morono, have clearly outlined their vision for the future. With the strong presence of Archaea in the deep ecosystem, they have stated that they "intend to study their lifestyle and metabolism, strategy for long-term survival, and ecological roles."

They will use CHIKYU, the world's only riser-equipped research vessel and drilling platform. By presenting and discussing their findings, it is hoped that scientists will be able to gain a more complete, reliable and accurate picture of the deep sea floor.

These microbes are literally dead by our normal standards, barely using any energy at all. Unlike bacteria, which reproduce rapidly, Archaea double themselves less than once a century.

Scientists believe that if there are any life on the other planets in our solar system, it will be like these Archaea, living at an extremely slow pace of life due to the similar conditions. Hypothetically, similar organisms may be living in the vents beneath the ice of Europa, or in the frozen water of Mars, so developing an understanding the Archaea is vital. Additionally, these microbes are likely to survive major Earth impacts by asteroids or a nuclear fallout, meaning that the this deep sea region is a likely refuge during extinction events.