Shikoku Basin  search
BTPacific Ocean
 .North Pacific
 ..Northwest Pacific
 ...Shikoku Basin
RTIzu-Bonin Arc
 Philippine Sea
 DSDP Site 442
 DSDP Site 443
 DSDP Site 444
SNUndersea feature between Shikoku on the NW and the Bonin and Volcano islands to the SE. This term has multiple hierarchies.