319 research outputs found
Petrographical Characteristics of Ultramafic Xenoliths from Megata Volcano, the Northeast Japan Arc
Petrological feature of spinel lherzolite xenolith from Oki-Dogo Island: An implication for variety of the upper mantle peridotite beneath southwestern Japan
Spinel lherzolite is a minor component of the deep-seated xenolith suite in the Oki-Dogo alkaline basalts, whereas other types of ultramafic (e.g. pyroxenite and dunite) and mafic (e.g. granulite and gabbro) xenoliths are abundant. All spinel lherzolite xenoliths have spinel with a low Cr number (Cr#; 89), and are rarely associated with Fe-rich cumulus mafic and ultramafic xenoliths. This indicates that the LREE-enrichment in mantle rocks has been more prominent and prevalent than Fe and other major-element enrichment during the metasomatism
Reaction of Perodotite Xenoliths with Hoto Magmas as an Analogue of Mantle- Melt Interaction: Microscopic Characteristics
Geological, pertrographical and petrological characteristics of ultramafic-mafic xenoliths in Kurose and Takashima, northen Kyushu, southwestern Japan
Classification of peridotite xenoliths in cale-alkaline andesite from Iraya volcano, Batan Island, the Philippines, and its genetical implications
A cold seep triggered by a hot ridge subduction
The Chile Triple Junction, where the hot active spreading centre of the Chile Rise system subducts beneath the South American plate, offers a unique opportunity to understand the influence of the anomalous thermal regime on an otherwise cold continental margin. Integrated analysis of various geophysical and geological datasets, such as bathymetry, heat flow measured directly by thermal probes and calculated from gas hydrate distribution limits, thermal conductivities, and piston cores, have improved the knowledge about the hydrogeological system. In addition, rock dredging has evidenced the volcanism associated with ridge subduction. Here, we argue that the localized high heat flow over the toe of the accretionary prism results from fluid advection promoted by pressure-driven discharge (i.e., dewatering/discharge caused by horizontal compression of accreted sediments) as reported previously. However, by computing the new heat flow values with legacy data in the study area, we raise the assumption that these anomalous heat flow values are also promoted by the eastern flank of the currently subducting Chile Rise. Part of the rift axis is located just below the toe of the wedge, where active deformation and vigorous fluid advection are most intense, enhanced by the proximity of the young volcanic chain. Our results provide valuable information to current and future studies related to hydrothermal circulation, seismicity, volcanism, gas hydrate stability, and fluid venting in this natural laboratory
TIARES Project -Tomographic investigation by seafloor array experiment for the Society hotspot
http://www.godac.jamstec.go.jp/darwin/cruise/mirai/mr08-06_leg1/
Magmatic Products by Ocean Floor Spreading in MAR : Preliminary Analyses of Peridotites from IODP Exp.304/305 at Atlantis Massif, MAR 30°N
金沢大学大学院自然科学研究科4the International Symposium of the Kanazawa University 21st-Century COE Program, Promotion Envirnmental Research in Pan-Japan Sea Area -Young Researchers\u27 Network- , DATE:March 8-10,2006, PLACE: Kanazawa Excel Hotel Tokyu, Japan, Sponsors: Japan Sea Research Institute / UNU-IAS(United Nation University Institute of Advanced Studies), Ishikawa Prefectural Government, City of Kanazaw
- …