Studying Mid-Ocean Ridge Processes with Observatory Technologies: What Have We Seen After Five Years?

Real-time, continuously recording observatory technologies are now installed at three mid-ocean ridge locations, serving disciplines from geophysics to biology.  All three observatories provide power and communications to seafloor networks of sensors, with data being transmitted to land via long-distance cables or a satellite link. Two observatories have been operating since 2010 (EMSO Açores and NEPTUNE Endeavour), and the third (OOI Axial Volcano) went online in 2015.

The resource potential of slow- and ultraslow-spreading ridges

Increasing commercial interest in mining of seafloor massive sulfides and the political will to secure metal supply for global industries has led to an ongoing debate about their possible resource potential. The need for such assessments is now more urgent, as a number of countries and international consortia have begun to invest in intensive exploration campaigns. A growing database of global SMS occurrences is providing clues to the likely distribution, size and grade of the deposits. More than 330 sites of seafloor mineralization are now known on the ocean floor.

Geochemistry and biogeochemistry of deep-sea hydrothermal system

Deep-sea hydrothermal systems and associated biota have long attracted interest of many researchers (e.g., Humphris et al., 1995; Van Dover, 2000; Wilcock et al., 2004). In the past few decades, particular attention has been paid to chemolithoautotrophic microorganisms that sustain the hydrothermal vent-endemic animal communities as the primary producer.

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.