Annotated record of the detailed examination of Mn deposits from the SOUTHTOW cruise over the Manihiki Plateau, Pacific Ocean@en

Dredging in the Danger Island Troughs, which divide the High and Western parts of the Manihiki Plateau, recovered several fresh pebbles of olivine tholeiite and tholeiite, a single pebble of highly altered gabbroic cumulate, and several dozen pebbles of altered variolitic basalt. Troughs suggests that at one time the troughs were the site of active faulting. A tectonic model for the evolution of the plateau, consistent with a fracture zone origin for the Danger Island Troughs, requires the formation of the Manihiki Plateau at a triple junction of the Pacific, Farallon, and Antarctic plates.