As for bombing ranges in Nevada, I understand that the underground caverns formed by the underground nuclear tests of a few decades ago are lined with thick glass, a later stage of what happens to sand under heat and pressure, yes?
Well normally if sand was subjected to both heat and pressure, it would be as a result of being deep underground, and in these circumstances it would cool slowly and give us the crystalline metamorphic rock quartzite. Glass, you will recall, is what you get when molten rock cools
quickly, so that there's no time for crystallization.