This has to be kicking the hypothesis about “anthropogenic” global warming in the butt.
The globe wasn’t getting warmer, seems this particular spot was ALREADY pretty warm.
Hot enough to melt rocks, anyway.
This is the way the planet vents its internal heat, you know. The internal temperature of the planet is kept at relatively high levels for two primary reasons.
One is that tremendous pressure, as the planet core is approached more and more closely, resulting in converting this huge well of gravitional energy into heat.
The other is the continuing radioactive decay of certain unstable elements in this molten mantle, which generates even more heat. While there are not that many molecules of any one given element packed in any one place, the cumulative effect of of all the radioactive decay products, and the energy released, can add up to a pretty respectable number across the entire core of the earth.
Then there is the factor of the earth’s mantle crust being something of an insulating blanket, and the heat only escapes when a volcano, or some similar vent, is opened.
“While there are not that many molecules of any one given element packed in any one place”
That is not necessarily true.
I would like to compliment you for explaining the vulcanic nature of the Earth in laymen’s terms.
Good communication is having everyone getting a ‘picture’ in their head.
Great communication is having everyone getting the same ‘picture’.
You did great!