Shimada Seamount is a seamount in the Pacific Ocean located southwest of Baja California Sur in Mexico. It is a shallow seamount, reaching a depth of 30 metres (98 ft) below sea level and is a regular single-peaked mountain with a westerly spur and little relief otherwise. A platform lies at a depth of 180 metres (590 ft). Talus deposits surround the seamount at its base. The seafloor underneath Shimada is between 18 million and 21 million years old and lies at a depth of about 4,100 metres (13,500 ft); other than abyssal hills at a distance of up to 1 kilometre (0.62 mi) from Shimada, Shimada is isolated. Volcanic rocks taken from Shimada are considered to be icelandites.