Coal Nunatak (72°7′S 68°32′W / 72.117°S 68.533°W / -72.117; -68.533) is a flat-topped rock mass with steep cliffs facing south, standing 2 nautical miles (4 km) southwest of Corner Cliffs on the southeast corner of Alexander Island, Antarctica.
Lincoln Ellsworth first noted it from the air on November 23, 1935, and mapped it from photos obtained on that flight by W.L.G.
These stumps have eroded out of a layer of coarse, brown, fluvial sandstone that contains a large amount of volcanic sediment.
Where the associated forest floor is covered by white tuffaceous sandstone, parts of the trunks are totally carbonized.
Two other distinct fossil forests with standing trunks are exposed in the cliffs of the south end of Coal Nunatak.