The Boomerang Seamount is an active submarine volcano, located 18 km (11 mi) northeast of Amsterdam Island, France.

It was formed by the Amsterdam-Saint Paul hotspot and has a 2 km (1.2 mi) wide caldera that is 200 m (660 ft) deep.

[4] The seamount is located on the mainly undersea Amsterdam–Saint Paul Plateau of the Antarctic Plate,[3] which was predominantly formed by the volcanic hotspot.

[6] The plateau which extends north west towards the Nieuw Amsterdam Fracture Zone (Amsterdam Fracture Zone) and south to beyond the island of St Paul with its presently known active area being delimited by the St. Paul Fracture Zone,[7] is a 250 by 200 km (160 by 120 mi) feature of the sea floor near the Southeast Indian Ridge, which is an active spreading center between the Antarctic plate that the seamount lies on, and the Australian Plate.

[10] Helium isotopic compositional studies are consistent with its formation from the combined effects of accretion at the mid-ocean ridge and mantle plume activity of a hot spot.