How the ancient supercontinent Pangea may have helped create the Earth’s coal

The vast majority of the Earth's coal was laid down at the same time (geologically speaking) and in a uniform manner. A new paper challenges conventional wisdom on this point and argues for a different cause.

from ExtremeTech http://www.extremetech.com/extreme/221848-how-the-ancient-supercontinent-pangea-may-have-helped-create-the-earths-coal