Lithospheric heterogeneities, hydrothermal regimes, and links between abiotic and biotic processes at slow spreading ridges

Lithospheric heterogeneities, hydrothermal regimes, and links between abiotic and biotic processes at slow spreading ridges
International Workshop on Marine Research Drilling in the Atlantic (Magellan Workshop Series)
10-12 September 2008; Montpellier, France (Participation by invitation only)

Conveners: Marguerite Godard (Université Montpellier 2), Gretchen Früh-Green (ETH Zurich), and Christopher MacLeod (Cardiff University)

In contrast to the apparently regular layered and spatially homogeneous oceanic lithosphere formed at fast-spreading ridges, that generated at slow- and ultra-slow spreading centres is markedly heterogeneous on a variety of scales, reflecting profound variations in magmatic and tectonic activity along and across isochrons. Recent discoveries of low-temperature hydrothermal vents specific to mantle exhumation areas and of abiotic synthesis of hydrocarbons directly associated with these vents highlights the strong links between the structural and petrological heterogeneities at slow spreading ridges and the development of conditions favourable to life.

This workshop will bring together specialists in marine geology and geochemistry, oceanography, biology and petrology with an interest in the geological, physical and chemical evolution of the accretion system at slow spreading ridges and the life it sustains. Discussions will focus on: (1) Tectono-magmatic processes controlling lithological heterogeneity of the lithosphere in the Atlantic; (2) Fluid-rock interaction & production of abiotic components to sustain life at depth; (3) Variability and controls on microbial activity at depth and the link between abiotic and biotic processes in heterogeneous lithosphere.

This workshop aims to develop an European-initiated, IODP drilling proposal and explore novel uses of mission-specific platforms to investigate these processes with a particular focus on Atlantis Massif (Mid-Atlantic Ridge, 30°N).

Note: InterRidge is providing some support for participants from non-ESF countries.