Marijuana on Federal Lands. Posted: January 27, 2014. With the legalization of marijuana in the State of Colorado, Mesa Verde National Park would like to provide clarification regarding the use of possession of marijuana on Federal lands.
Plate Tectonics. Plate tectonics is the movement of the Earth's crust through convection currents that occur in the mantle. Divergent plate boundaries occur where hot magma rises to the surface, pushing the plates apart. The mid-ocean ridges form at divergent plate boundaries.
A tectonic plate boundary always forms when two continental plates collide. Neither plate subducts because the crust have approximately the same density. Instead, the rocks are smashed together causing them to recrystallize due to the intense heat and pressure from the colliding plates.