That is an interesting theory but I think we would have strong evidence of that were it to be true. The earths magnetic field has reversed on average about every 400,000 years, if I remember correctly. We can see this in the crust of the earth looking at dipole minerals in the basaltic plains of the deep ocean. Again, my terminology is suspect. I haven't discussed this in a long while. I don't know if there is evidence of cooling and warming along this timeline.
I don’t know if you have followed any of the Mars mission and viewed the pictures and the articles, but as I read this I thought of our discussions thus far and thought it may interest you..
Once upon a time, Mars was a world of cataclysms. Its namesake, the Roman war god, would likely have been pleased to see it in action: Volcanic cathedrals of flame unleashed armies of molten rock that obliterated the planet’s surface.
<snip> much more to read, should you wish..
And NASA’s InSight lander, which has been peeking inside Mars for two years now, has picked up on some curious seismic signals emanating from one such site of youthful volcanism. The results, which were presented at a conference in December, are not definitive. But they suggest that InSight could be hearing the sounds of convulsing magma — the drumbeat of volcanic warfare presumed to have fallen silent eons ago.
“It is a very exciting finding and, if confirmed, suggests that Mars could enter the pantheon of currently volcanically active worlds within our solar system,” said Christopher Hamilton, a planetary scientist at the University of Arizona.
If future data and analyses establish that magma does exist, that would be a revolutionary reveal. It would be solid evidence in support of a suspicion that scientists have harbored for some time now: Rocky worlds that look volcanically dead aren’t, said Paul Byrne, a planetary scientist at North Carolina State University. They are alive — or, to put it another way, “these worlds are just dying very slowly.”
We have almost no certain knowledge about the inside of worlds, including our own. That’s a problem. “With few exceptions, the thermal evolution of a planet governs everything,” said Byrne, from the state of the surface, on which biology can take hold, to the evolution of the world’s atmosphere. “It’s one story — it’s the planet cooling down. It’s the only thing that matters.”
Volcanism is the outward expression of a planet’s internal fire, a major way for it to lose heat while giving the surface a new coat of paint. If we understand how volcanic Mars is, how capable it is of making eruptible magma, we can understand its internal evolution and compare it to Earth’s. So if it really is magma that InSight is hearing, then we come closer to understanding not only Mars, but our own planet as well. <snip>
Magna and molten~~ fascinating..https://amp.theatlantic.com/amp/article/617951/