LEGENDE lien hiérarchique (hyperonyme, hyponyme) lien partitif stockage de leau dans lien cause-effet lien effet-cause processus Les termes en rouge font lobjet dune fiche courte dans le dictionnaire terminologique et les termes en bleu font lobjet dune fiche longue. Les termes soulignés font lobjet dune arborescence développée. lien spatial lien temporel objet détude affectée par la présence dhydrogène dans lolivine polymorphe

Earths water reservoir* external reservoir hydrosphere volatile components in the atmosphere oceanslakesriverswater tablesglaciers *Il peut sagir à la fois dun lien hiérarchique et dun lien partitif car les réservoirs interne et externe sont deux types de réservoir mais on peut également dire que les réservoirs deau sur Terre se composent dun réservoir interne et dun réservoir externe. Earths water budget:

internal reservoir crust mantle oceanic lithosphere continental lithosphere upper mantletransition zone lower mantle minerals nominally hydrous minerals nominally anhydrous minerals amphibole olivine pyroxene garnet ringwoodite wadsleyite orthopyroxeneclinopyroxene as H + ion + lithosphere mica sediments serpentine core … periclase majorite fluid as a –OH radical as H2O mole …

Hydrogens entrance in the mantle hydrothermalism oceanic lithosphere hydration subduction hydrogen enters the mantle hydrogen ascent hydrogen injection into the internal reservoir hydrogen release at 150 km depth hydrogen diffusion in minerals

diffusion of hydrogen in minerals atomic diffusionionic diffusion inclusionpoint defect fluid inclusion glass inclusion divalent cation substitutes for an hydrogen atom hydrogen atom associate with oxygen atom formation of an hydroxyl group charge defect ion H + incorporates in charge defect charge defect associate with point defect ion H + associates with oxygen atom formation of an hydroxyl group nominally anhydrous minerals nominally hydrous minerals

Special case: olivine hydrogen diffusion in olivine tectonics physical property of olivine electrical conductivity phase equilibrium rock transformation metamorphism metasomatism dehydration anisotropy equation of state

Earths sciences geophysics internal geophysics external geophysics … geodynamics tectonicsgeostatisticsseismology rheologyplate tectonics deformation subduction partial melting magma genesisconvection ……

Effect of hydrogen diffusion in olivine on rheology hydrogen diffusion in olivine lower viscosity ductile deformation brittle deformation lithosphere fracture into plates plate tectonics creep shear zone fault fold

hydrogen diffusion in olivine no hydrogen diffusion in olivine hydrous partial melting anhydrous partial melting magmas production volcanism magma eruption continental and oceanic crust formation dehydration of generated magmas pressure increase deep earthquake micro-earth quake permeability Effect of hydrogen diffusion in olivine on partial melting

hydrogen diffusion in olivine decrease of liquidus temperature and increase of solidus temperature rocks melting ultramafic magma Effect of hydrogen diffusion in olivine on magma genesis magma genesis

convection instabilities subduction instabilities lithosphere does not cool the mantle sufficiently partial melting instabilities convection subduction Effect of hydrogen diffusion in olivine on convection hydrogen diffusion in olivine no hydrogen diffusion in olivine

plate tectonics convection convergencedivergencetranscurrence subductioncollisionobduction island arc orogeny volcanism oceanic accretion oceanic trench fault + Reminder: mid-ocean ridge orogeny + continental rif island arc +

subduction 2 oceanic plates convergean oceanic plate and a continental plate converge the heavier plate subducts lithosphere ingestion partial melting magma genesis a part of the magma remains in the asthenosphere island arc oceanic plate subducts lithosphere ingestion partial melting magma genesis island arc Reminder: a part of the magma remains in the asthenosphere orogeny oceanic trench