Complex ridge-transform evolution and mantle exhumation at the St. Paul transform-fracture zone system, Equatorial Alantic.

Marcia Maia1, Susanna Sichel2,Anne Briais3, Daniele Brunelli4,5, Nicolas Ferreira1, Marco Ligi5, Thomas Campos6

Sub-seafloor massive sulfide deposits: a resource for the near future?

Europe, and the world in general, need new sources of base and strategic metals, given a growing global population, with growing effluence, which will reach ten billion human beings before (slowly) decreasing. One of the new, global scale sources of mineral resources is the deep seafloor, and there are 25 exploration concessions already granted by ISA (International Seabed Authority) in the Area, mostly for polymetallic nodules and sms deposits, and still others in waters under national jurisdiction.

Hydrothermal energy transfer and the ocean carbon cycling

Hydrothermal energy transfer and the ocean carbon cycling

N. Le Bris, UPMC - CNRS, France

East Pacific Rise 15.4°N: A geochemical approach at very small spatial and temporal scale in a hotspot-ridge context.

East Pacific Rise 15.4°N: A geochemical approach at very small spatial and temporal scale in a hotspot-ridge context.

A review of electromagnetic approaches to the seafloor spreading ridge system

Electrical conductivity (or its reciprocal resistivity) is sensitive to temperature, component, and phase of materials, and the degree and form of interconnection of material in matrix for two or more materials’ system.

First data on composition of the NW Pacific Oceanic Lithosphere exposed along the Stalemate Fracture Zone.

The Stalemate Fracture Zone (FZ) is a 500 km long SE-NW trending transverse ridge between the northernmost late-Cretaceous Emperor Seamounts and the Aleutian Trench. Sampling at the Stalemate FZ and the fossil Kula-Pacific Rift valley was carried out during the R/V SONNE cruise SO201 Leg 1b in 2009 in frame of Russian-German project KALMAR. We present in this work results on mineralogical composition of mantle peridotite dredged at the station DR37 from the northernmost  part of the Stalemate FZ on border with Aleutian Trench.

Melting of peridotite beneath Mid Ocean Ridges: Simplicity and complexity

Chemical and isotopic compositions of mid ocean ridge basalts (MORBs) are relatively homogeneous when compared with the basalts from other tectonic settings, e.g., ocean islands and arcs. Nevertheless, their variations indicate that the source mantle beneath MORs should be heterogeneous and the melt generation and coalescence processes are complex. I here present an overview of such the melting processes of peridotite beneath MORs.

Review of Japanese Taiga project 1, Indian Ocean

InterRidge-Japan community conducted an interdisciplinary research project TAIGA, Trans-crustal Advection and In-situ biogeochemical processes of Global sub-seafloor Aquifer, from 2009 to 2013. The flows and chemical compositions of subseafloor fluid are regulated by tectonics, and are modified by the host rocks. During 5 years project, we selected three integrated study sites of different tectonic settings and carried out multi-disciplinary studies.

Review of Japanese Taiga project 2, Okinawa Trough

The Okinawa Trough is a back-arc basin behind the Ryukyu trench-arc system and located along the eastern margin of the Eurasian continent. Based on geophysical and geological studies, the Okinawa Trough is considered a back-arc basin in the rifting stage. Such a tectonic setting is characterized by development of normal faulting in brittle continental crust and frequent intrusion of a magma, which can be expected to provide favorable environment for development of a hydrothermal system.

Tectonic Processes of the Australian-Antarctic Ridge

The Australian-Antarctic Ridge (AAR) has been remained uncharted until 2011 because of its remoteness and harsh weather conditions. From 2011, the multidisciplinary ridge program initiated by the Korea Polar Research Institute (KOPRI) surveyed the little explored eastern segments of the Australian-Antarctic Ridge (AAR) to characterize the tectonics, geochemistry, and hydrothermal activity of this intermediate spreading system.