During a 32-day marine geophysical expedition aboard the R/V Maurice Ewing, scientists investigated the fate of the Ontong Java oceanic plateau (OJP) at the Solomon island arc (Figure 1). The purpose of the cruise was to examine whether oceanic plateaus subduct, obduct, or partially obduct at subduction zones. With an area of 1.86×106 km2 and a crustal thickness of 25–43 km, the OJP is the largest and thickest oceanic plateau on Earth and one of the few Pacific oceanic plateaus that is actively converging on an island arc. Obducted remnants of the OJP may occur in a Neogene accretionary prism, the Malaita anticlinorium, which separates the Solomon Island volcanic arc from the OJP (Figure 1).