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Drain the Ocean Facts

Drain the Ocean

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  • We know the surface of Mars or Venus better than 4/5 of our own planet.

  • If we superimposed the tracks of survey missions in the Pacific onto a map of the US, we still wouldn't have discovered several large states!

  • The ocean surface isn't flat. The mass of underwater mountains affects the local gravity and that affects the shape of the water surface.

  • Only about 5 percent of the global ocean floor has been mapped in detail.

  • "We know more about the backside of the moon than we do about the bottom of the ocean." - Dr. Peter Rona, Professor of marine geology and geophysics at Rutgers University.

  • It would take 125 ship years to map the oceans in sonar.

  • The waters that cover the globe hold more than 97% of our planet's 3D habitat space.

  • The average ocean depth is approximately 2.2 miles (12,000ft).

  • Bengal fan is over 3000 km long, 1000 km across and up to 16 km deep in sediment.

  • Monterey canyon has a similar relief and length as the Grand Canyon.

  • The MARS project is essentially a giant plug under 3000ft of water supplying over 10,000 watts of power for scientific research equipment.

  • Zhemchug Canyon is around 2600 metres deep and 100 km across at its widest point. Zhemchug has a drainage area of 11350 km2 and a volume of 5800 km2.

  • The Hawaiian Islands have 410,000 acres of living reef in the main islands alone, more than the landmass of O'ahu.

  • Hills built by deep sea coral stand in up to 1500 metres of water. The 'Matterhorn' coral hill is 150 metres high– that's as high as downtown Miami's skyline!

  • Deep water corals are more abundant and have a greater range than shallow water corals.

  • The Bahamas are home to the largest cliffs on the planet. Some have sheer drops of up to 4,000 m.

  • The Mid Oceanic Ridge is the world's longest mountain chain at more than 56,000 kilometers (35,000 miles), running along the centre of the ocean basins and joining up around the globe like the seams on a basketball.

  • The mid ocean ridges of the world are so long they could go right around the Earth twice!

  • The rift valley of the Mid-Atlantic Ridge is as deep as the Grand Canyon but ten times as wide.

  • The valley in the Romanche Fracture Zone is 200 miles long, 20 miles wide and 4 miles deep. This is four times the depth of the Grand Canyon.

  • The Romanche Fracture Zone valley has 10 times the flow of the Amazon River flowing through it's basin.

  • A North African submarine landslide flowed through a canyon and into the abyssal plain. It flowed at rates of over 60ft/second, was over 100 miles wide and travelled over 100 miles to the flanks of the mid ocean ridge.

  • Iceland is the only place where you can stand on the Mid Atlantic Ridge on dry land.

  • The Lost City site covers an area about the size of a football pitch in which there are forests of pure white columns, made of calcium carbonate.

  • The Poseidon Vent dwarfs most known black smoker vents at 18 storeys in height.

  • A spreading plume from a hydrothermal vent becomes a rotating lens of water, roughly 200 m thick, 2 km across and 300 m above the seafloor.

  • One hundred million years ago during the Cretaceous Period, hydrothermal vent plumes may have been able to reach the surface when layering of the ocean was less pronounced and less dense.

  • Overall, the diversity of the deep sea rivals that of rainforests on land.

  • There are up to 100,000 underwater mud volcanoes formed by gas escaping from some underground source under high pressure.

  • In the Gulf of Cadiz, some mud volcanoes reach 600 feet high and 3 miles in diameter.

  • If Mount Everest were placed on the Pacific seafloor next to Mauna Loa, Mauna Loa would tower over Everest by more than 8,150 meters!

  • The Nu'uanu debris avalanche contains enormous blocks ~30 km long, 17 km wide, and at least 2 km tall. The landslide is spread over a 23,000 km2 area.

  • The Tuscaloosa seamount or debris from the Nu'uanu debris slide is one mile deep and over 135 m2 in area. This rivals the size of the city of Atlanta.

  • Nu'uanu debris extending 150 miles from the island is the size of the state of New Hampshire.

  • Scientists have identified over fifteen giant landslides surrounding the Hawaiian Islands.

  • The world's oceans have between 70,000 and 100,000 seamounts more than 1 km tall and as many as 1,000,000 over 100m tall!

  • Challenger Deep in the Mariana Trench is covered by nearly 35,813 feet of water.

  • The newly discovered deep spot, HMRG deep, is 36,000 deep. The location is so deep that Mt Everest could be placed within it and still have 1.6 km (1 mile) of water above it!

  • On 23rd January 1960, the Trieste reached the bottom of the Challenger Deep. No person returned to this depth until 2012.

  • If an estimate of 4,000 volcanoes per million square kilometers on the floor of the Pacific Ocean is extrapolated for all the oceans than there are more than a million submarine (underwater) volcanoes. Perhaps as many as 75,000 of these volcanoes rise over half a mile (1 km) above the ocean floor.

  • Mauna Kea rises 9,750 meters (32,000 ft) from the ocean floor to an altitude of 4,205 meters (13,796 ft) above sea level.

  • The amount of lava erupted to form the Hawaiian Emperor Chain is calculated to at least 750,000 km3.

  • A volcanic island off the southern coast of Iceland (Surtsey) was formed in a volcanic eruption that began 130 m below sea level and reached the surface on the 14th November 1963. The island reached its maximum size of 2.7 km2. Since then wind and wave erosion has seen the island diminish in size, and as of 2007 the surface area was only 1.4 km2.

  • Oceans are expanding; the Atlantic grows by 2.5 cm annually in median dorsal axis, and the Eastern Pacific can reach growths of up to 15 cms/yr.

  • The oldest known ocean crust discovered is 3.8 billion years in Greenland. Scientists believe this rock was pushed to the surface in a collision between continents.

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