Expression of Interest to participate in IODP³ SPARC Expedition: CHEMS *Now Open*

Express your interest to take part in NEW IODP³ SPARC Expedition: Chemical
and Energy exchanges between mantle, Magma and Seawater (CHEMS)!

Formation, aging and recycling of oceanic lithosphere are fundamental components of plate tectonics, which drives global cycles of energy and matter on Earth. Mid-ocean ridges are dynamic environments in which magmatic processes, tectonic deformation and hydrothermal circulation are tightly intertwined. These processes are all influenced by the initial thermo-chemical heterogeneities of the sub-ridge mantle, and account for the largest fluxes of energy and matter from the deep Earth to the surface, with volcanism along ⁓60000 km of oceanic ridges representing their most evident manifestation. While high- to low-temperature processes driving the formation and evolution of oceanic lithosphere are often approached as separate entities, the lithological, geochemical and rheological heterogeneities formed during mantle melting and magmatic activity strongly influence deformation patterns, which in turn control melt focusing and hydrothermal fluid circulation within the oceanic lithosphere.

The CHEMS project aims to bridge the gap between these processes, by determining how initial mantle thermo-chemical heterogeneities and coupled magmatic, deformation and hydrothermal processes interact to shape the physical and chemical evolution of the oceanic lithosphere. It will focus on relatively magma-poor segments of a slow-spreading ridge where detachment faults exhume mantle and gabbroic rocks, and where magmatic and hydrothermal processes strongly interact with lithospheric deformation during exhumation.

CHEMS will use complementary ODP and IODP assets drilled along the Mid-Atlantic Ridge, namely the Atlantis Massif (30°N), the Kane Fracture Zone (23°N) and the Fifteen-Twenty Fracture Zone (15°20”N). Together, these legacy cores capture the strong architectural heterogeneity of slow-spreading oceanic lithosphere and encompass contrasting mantle thermo-chemical characteristics, allowing to determine how regional and local heterogeneities control feedback processes between magmatic processes, deformation and hydrothermal alteration.

This Expedition places particular emphasis on collaborative interdisciplinary sample characterisation and correlated mapping. This approach will provide centimetre-scale, pixel-by-pixel structural and chemical mapping of melt- and fluid-rock interactions, their relationship with deformation, and with the redistribution of elements during high- to low-temperature processes.

Applications to take part in this expedition will open later in 2026, however, if you would like to be the first to receive information about this exciting expedition we are asking potential applicants to complete out Expression of Interest form below.

This is not compulsory, does not commit you to apply, and not completing this form does not influence the evaluation of any application you make in any way. However, we strongly encourage completion of this form to ensure we can best support you if you proceed to apply. completion will take less than two minutes!