Why is deep water at the ocean floor very cold if it is closer to the extremely hot core of the earth?

Question

Why is deep water at the ocean floor very cold if it is closer to the extremely hot core of the earth?

Answer 1

The thickness of the crust under the ocean is about 5 or 6 miles, so there is plenty of insulation from the mantle.  The mantle is about 1800 miles thick, then you come to the outer core.  Anyway, the point is that there is about 5 miles of insulation between the ocean and the heat source, except in the case of hot spots and plate boundaries.

Answer 2

i'm not going to answer your question but i want to say that despite the idea of some of the people, thickness of the oceanic crust is not constant it has huge variation even it can become zero in some parts so called as MID-OCEANIC RIDGE i mean that in these part the mantle reach to the sea floor

Answer 3

What warms the surface of the earth - and the water - is the energy from the sun:  Deep water is much closer to the earth's surface than it is to the core - if you dig down a few feet anywhere on earth, the soil will be cooler than at the surface. The sun's heat can't penentrate to the deeper water, so it does not get heated, and also being cold it does not rise to the surface but stays cold and deep.

Answer 4

Even though it is CLOSER to the ocean floor does not mean that it is close. The Earth's crust is approximately 5 miles thick. And this cold water is in constant motion which keeps it from just heating up. Either way, heat rises, so the hot water moves toward the surface and the cold water sinks.

Answer 5

It isn't very close to the core, cold water sinks whereas warm water rises, and the energy of the Sun is of much more consequence, and that hits the surface of the ocean rather than the seabed.  Sunlight fails to penetrate deeper than around two hundred metres.