The Tuscaloosa Seamount is an undersea mountain in the Hawaiian archipelago. It is about northeast of the island Oûahu.
Tuscaloosa Seamount is composed of volcanic rock, but in contrast to the overwhelming majority of seamounts, it is not a submarine volcano. It is a huge block of rocks that broke off about two million years ago at the Nuûuanu submarine landslide when the volcano Koûolau collapsed.
The Tuscaloosa Seamount is long and wide. Its shallow summit rises across the sea bottom but is below sea level.