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Tom Mazanec
2017-Mar-20, 03:21 AM
How much of the Earth's heat outflow is generated by:
1) Radioactive decay
2) Solar and lunar tides
3) Shrinkage of the Earth's radius
4) Migration of dense matter into the core
5) Anything I haven't thought of?

profloater
2017-Mar-20, 08:19 AM
Well you left out stored solar heat. Lord Kelvin famously calculated an age of a few thousand years from assumptions that ignored in particular radioactive decay.

geonuc
2017-Mar-20, 10:27 AM
As mentioned in the other thread you started related to this subject, residual heat from formation accounts for about half.

grapes
2017-Mar-20, 01:29 PM
How much of the Earth's heat outflow is generated by:
1) Radioactive decay
2) Solar and lunar tides
3) Shrinkage of the Earth's radius
4) Migration of dense matter into the core
5) Anything I haven't thought of?
6) growth of the inner core by cooling
7) sunshine/cooling of crust
8) volcanic activity
9)

Swift
2017-Mar-20, 02:23 PM
First hit on Google of "Earth's geothermal budget"
https://en.wikipedia.org/wiki/Earth's_internal_heat_budget

The flow of heat from Earth's interior to the surface is estimated at 47 terawatts (TW)[1] and comes from two main sources in roughly equal amounts: the radiogenic heat produced by the radioactive decay of isotopes in the mantle and crust, and the primordial heat left over from the formation of the Earth.[2]

Earth's internal heat powers most geological processes[3] and drives plate tectonics.[2] Despite its geological significance, this heat energy coming from Earth's interior is actually only 0.03% of Earth's total energy budget at the surface, which is dominated by 173,000 TW of incoming solar radiation.[4] The insolation that eventually, after reflection, reaches the surface penetrates only several tens of centimeters on the daily cycle and only several tens of meters on the annual cycle. This renders solar radiation irrelevant for internal processes.[5]