LII.—The Bonin Island Sambar

The Flora of the Bonin (Ogasawara) Islands

Origin of depleted basalts during subduction initiation and early development of the Izu-Bonin-Mariana Island arc: Evidence from IODP Expedition 351 Site U1438, Amami-Sankaku Basin

The Izu-Bonin-Mariana (IBM) island arc formed following initiation of subduction of the Pacific plate beneath the Philippine Sea plate at about 52 Ma. Site U1438 of IODP Expedition 351 was drilled to sample the oceanic basement on which the IBM arc was constructed, to better understand magmatism prior to and during the subduction initiation event. Site U1438 igneous basement Unit 1 (150 m) was ...

Island Sound Long Island Sound Long Island Sound Long Island Sound Long Island Sound

first method, samples are collected and the concentration of DON or individual DON components are monitored over time. To measure DON flux rates using 15N tracer techniques. all of the DIN forms (N~ + , NO3 -.and NO2 -) must be removed, and the DON pool must be isolated with a high efficiency. At present. there are three basic approaches used to isolate DON-wet chemistry, ion retardation, and d...

Frequency-dependent shear wave splitting beneath the Japan and Izu-Bonin subduction zones

Despite its importance for ourunderstandingof physical processes associatedwith subduction, the geometry of mantle flow in subduction zones remains poorly understood, particularly in the mantle wedge above subducting slabs. Constraints onmantle flowanddeformation canbeobtainedbymeasurements of shearwave splitting, a valuable tool used to characterize the geometry and strength of seismic anisotr...

Petrology and Geochemistry of Boninite Series Volcanic Rocks, Chichi-jima, Bonin Islands, Japan

An Eocene submarine boninite series volcanic center is exposed on the island of Chichi-jima, Bonin Islands, Japan. Five rock types, boninite, bronzite andesite, dacite, quartz dacite, and rhyolite, were distinguished within the boninite volcanic sequence on the basis of petrographic and geochemical observations. Boninite lavas contain high magnesium, nickel, and chromium contents indicative of ...