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The simple answer to this question is that cold seawater is denser than warm seawater, so it sinks and fills up the abyssal ocean. The water that fills up the abyssal ocean comes from the polar regions. Here's a 1990s plot of temperature in the Atlantic, retrieved from the WOCE Atlantic Ocean Atlas: You can see that the coldest water is coming from the ...


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depths of our planet How deep? "Deep" is a relative thing. You can have 10 kilometres deep, or 5000 kilometres deep. Super high pressure at the center of it It's not the pressure per se that's causing the heat, it was the process of getting to the pressure when the Earth's formed. Compression creates heat. That's easy to know - just touch a ...


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The trouble with geothermal gradients is they are not the same everywhere. It is generally accepted that the geothermal gradient is 25-30 °C/km but there can be local variations. In South Australia the gradient is generally 30° C/km, but in the deeper parts of the Cooper Basin the gradient is 55-60 °C/km. Elsewhere, at a depth of 200 ft the temp is 11 C. In ...


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Geophysicists and geochemists agree on some issues, but agree to disagree on others. Where they agree is that much of the thermal energy in the Earth's core is primordial. A huge amount of heat resulting from the collisions of the myriad objects that collectively formed the Earth. Yet more heat resulted when the early Earth differentiated into an iron-heavy ...


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Cold water is denser than warm water. The very cold water in the Arctic and Antarctic regions sinks and circulates deep undersea.


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William Thomson's calculation is a poor first order approximation: take a molten blob of earth and calculate how long it takes too cool to near zero K. What Thomson couldn't know, for one thing, is how high initial temperatures got during the initial accretionary phase of earth's formation. Another thing that Thomson couldn't know in the mid 19th century is ...


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William Thompson, the first baron Kelvin worked out that the Earth was around 20 to 400 million years old, based on the rate of cooling from an assumed molten state. This would imply that the Earth's primordial heat would already be essentially lost, so you could argue the answer is zero (assuming Kelvin's calculation remains reasonable). However once ...


1

Unlike fat under the skin of animals (& humans) there is no worldwide layer or layers of hydrocarbons below the surface of the Earth. Crude oil, and other hydrocarbons, occurs in distinct deposits at various locations globally. At some locations some deposits overlie each other and at others there may be just one layer but at many other locations there ...


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