Answer is Europe environmental solutions must be confined by political borders
Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors. Conditions like these are found deep within the Earth or where tectonic plates meet. In the rock cycle, there are three different types of rocks: sedimentary, igneous, and metamorphic. Sedimentary and igneous rocks began as something other than rock. Sedimentary rocks were originally sediments, which were compacted under high pressure. Hope this helps!
The atmosphere and Earth's interior are layered by density. Gravity pulls more strongly on denser materials so denser materials are at the center of things. Earth's core, at its center, is denser than its crust.