Final answer:
The U8 coal deposits are indicative of ancient forest presence and support the theory of continental drift, which is a cornerstone of the broader theory of plate tectonics, by documenting the historic movement of continents.
Step-by-step explanation:
U8 coal deposits indicate the presence of ancient forests, supporting the theory of continental drift.
U8 coal deposits provide important evidence for the theory of plate tectonics, particularly supporting the sub-theory of continental drift. Coal is formed from the remains of ancient plants and forests that, over millions of years under high pressure and heat, turn into coal. When coal deposits are found in regions that are currently cold and lack the vegetation typically associated with coal formation, it suggests that the continent has moved from a region with a climate that supported lush forests. Alfred Wegener's theory of continental drift, which is part of the broader plate tectonics theory, proposes that continents were once joined in a supercontinent called Pangea and have since drifted apart to their current locations.
Coal deposits, therefore, are part of the geological record that helps trace the movement of continents over time. Plate tectonics help explain this drifting process, as it accounts for the movement of Earth's plates on which the continents rest.