Last updated on August 31, 2019
The blue waters of earth’s oceans cover almost three-quarters of our planet, dominating its surface. The world beneath the water’s surface is the earth’s most mysterious and least explored region. Fifty percent of the world’s species live in the oceans, which have been home to life since it first evolved, over 4 billion years ago.
The seafloor is just as varied as land. Its features are mainly created by the movement of the plates that make up Earth’s crust. Where plates move apart, ridges open and create new ocean floor. Where plates collide, rock is pushed into Earth’s interior, forming deep trenches.
WATER IN OCEAN
Most of Earth’s water is found in its oceans, which cover much of the planet’s surface, with an average depth of around 3,370 m (12,240 ft). Deep ocean waters extend from the north and south poles right around the world to the equator. They vary considerably in properties such as saltiness, temperature, pressure, light penetration, and forms of life they support.
If the ocean waters were spread out evenly over Earth’s surface they would cover the entire surface to a depth of 2,800 m (8,200 ft).