1) The world's biggest mountain chain is underwater. Earth’s longest chain of mountains, the Mid-Ocean Ridge, is almost entirely below the ocean, stretching across a distance of sixty five thousand kilometers.

2) We tend to still solely grasp a fraction of the marine species in our oceans in tandem with the planet Register of Marine Species there area unit currently 240,470 accepted species, however this can be believed to be simply of a low proportion of the species that exist, with new marine life being discovered everyday.

3) It’s doable to seek out rivers and lakes below the ocean. once salt water and sulfide mix, it becomes denser than the remainder of the water around it, enabling it to create a lake or stream that flows below the ocean.

4) Only 5 percent of the planet’s oceans have been explored. As researchers strive to discover more, we’re continually getting to know our oceans better.

5) The bulk of life on Earth is aquatic. As so much of the Earth’s surface is underwater, it comes as no surprise that marine species outnumber those on land. But, it’s a fantastic ninety four per cent of the Earth’s living species exist inside the oceans.

6) The majority of life on Earth is aquatic. Marine species outnumber land species, which is not a very big surprise. 94% of the Earth's living beings live in the oceans.

What is the Mariana Trench?

Mariana Trench, otherwise known as Marianas Trench is a deep-sea trench in the floor of the western North Pacific Ocean where the deepest such trench known on Earth is situated to the east also to the south of the Mariana Islands.

Where is it located?

It is located in the Pacific Ocean somewhere between Hawaii and the Philippines near the small island of Guam, below the surface of the water.

Why is the Mariana trench so deep?

The western Pacific is the territory to some of the oldest seafloor in the world—about 180 million years old. The seafloor is made as lava at mid-ocean ridges. The Lava is extremely warm and buoyant, riding high on the underlying mantle.

What was found in the depths of the Mariana trench?

More ominously, at the bottom of the Pacific Ocean's Mariana Trench, Vescovo spotted what he said was a plastic bag and candy wrappers, which proved even the deepest depths of the world's ocean aren't excused from man-made interference.
-By Sarah Malik (SMSMB)