The Mariana Trench or Marianas Trench is located in the western Pacific Ocean about 200 kilometres (124 mi) east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width. The maximum known depth is 10,984 metres (36,037 ft) (± 25 metres [82 ft]) (6.825 miles) at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. However, some unrepeated measurements place the deepest portion at 11,034 metres (36,201 ft).By comparison: if Mount Everest were placed into the trench at this point, its peak would still be over two kilometres (1.2 mi) under water.
How deep is the sea?
Seventy percent of the earth’s surface is surrounded by oceans. Ninety-six percent of the water on earth is seawater. The average height of the global land is 860 meters, and the average depth of the ocean is 3680 meters. The deepest part of the ocean is in the Mariana Trench, its trench depth is more than 11,000 meters.
What kind of biological activity does each depth of sea have?
3m – Normal swimming depth
20m-30m – Coral reef / Recreational diving depth
70m – Whale sharks usually live in this layer of water
100m – North Pacific giant octopus / Professional diving extreme depth
200m – Giant oarfish
300m – Japanese spider crab
Below this depth, it is not a human world, but a world of marine life.
500m – Blue whale (Extreme depth)
600m – Macropinna microstoma
700m – European eel
900m – Giant squid
1300m – Leatherback sea turtle / Goblin Shark
1700m – Southern elephant seal
2000m – Black dragonfish
3000m – Sperm whale
3800m – The sinking depth of the Titanic
6500m – Submarine
8150m – Mariana snailfish
10928m – Garbage
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