1) In many a disaster scenario (most recently seen in Sluggy Freelance), some super-technology device, such as a mega-drill, frickin' superlaser, etc., bores a hole from the surface down to some ridiculous depth in very short time, and this usually is shown as causing some sort of catastrophe like a sudden volcano. I'm wondering if there would, in fact, actually BE any significant consequences from such an event, assuming it didn't occur right on top of a volcano that already exists and is about to blow. Say, here, in the heart of New York State, if I were to just magically bore a hole straight to the earth's core in a matter of a second, would there be a catastrophe, a small eruption, or nothing at all except a big hole that closed itself up to (some depth)?
2) Another common scenario in some SF has been either a base on a world like Pluto, or an earthlike world cast out into the void, where something happens and the whole base/planet cools to interstellar void temperatures. My question is if -- assuming you DON'T have any macroscopic reasons to be able to tell (if there were any biologicals present, they were already long dead, maybe mummified so there's hardly any water left in them, etc. -- you could tell that they had been, in fact, in a -200 deep freeze before they thawed out. That is, you step out into, say, a bunch of dirt and examine it. Can you tell that it was once subjected to -200 degree temperatures for a long period of time -- and could you tell this a year after it thawed, a hundred years, a thousand? Assume no biological activity to mess up your analysis (i.e., if it's been thawed for ten thousand years, there still haven't been any bacteria, etc., to start decay or other stuff going.)