Ōjin Seamount

is an underwater volcano (seamount) of the Hawaiian–Emperor seamount chain in the Pacific Ocean. Ōjin is an extinct volcano. 
The seamount is also known as the "Ōjin Guyot" because it has a flat top. This undersea geologic feature is also called a "guyot" or "tablemount".
This seabed mountain is named after Emperor Ōjin of Japan.
The last eruption from Ōjin seamount was 55 million years ago.