Reply to the correspondence: "On the fracture toughness of bioinspired ceramic materials"

This is a reply to the correspondence of Prof. Robert Ritchie: "On the fracture toughness of bioinspired ceramic materials", submitted to Nature Materials, which discusses the fracture toughness values of the following papers: Bouville, F., Maire, E., Meille, S., Van de Moort\`ele, B., Stevenson, A. J., & Deville, S. (2014). Strong, tough and stiff bioinspired ceramics from brittle constituents. Nature Materials, 13(5), 508-514 and Le Ferrand, H., Bouville, F., Niebel, T. P., & Studart, A. R. (2015). Magnetically assisted slip casting of bioinspired heterogeneous composites. Nature Materials, 14(11), 1172-1172.Comment: 5 pages, 2 figure

Shock-induced metallic iron nanoparticles in olivine-rich Martian meteorites.

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Shock-induced transformation of olivine to a new metastable (Mg,Fe)(2)SiO4 polymorph in Martian meteorites.

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Electrical conductivity of the serpentinised mantle and fluid flow in subduction zones

International audienceIn the mantle wedge of subduction zones, electromagnetic profiles reveal high electrical-conductivity bodies. In hot areas (>700 degrees C), water released by dehydration of the slab induces melting of the mantle under volcanic arcs that can explain the observed high conductivities. In the cold (= 1 m) fluids during progressive serpentinisation of the mantle wedge. These fluids can mix with arc magmas at depths and account for high chlorine/water ratios in arc lava

Kinetics and mechanism of antigorite dehydration: Implications for subduction zone seismicity

International audienceProperties of serpentine minerals are thought to influence the occurrence and location of intermediate‐depth seismicity in subduction zones, which is often characterized by two dipping planes separated by ∼30 km defining a double seismic zone. The seismicity of the lower plane is believed to be provoked by the dehydration of serpentine since the experimentally determined stability limit for antigorite matches hypocenter locations. This requires that the fluid produced by dehydration is released much faster than the typical time scale of ductile deformation mechanisms. Here we measured the kinetics of antigorite dehydration in situ at high pressure and high temperature by time‐resolved synchrotron X‐ray diffraction in a closed system. Antigorite dehydrates in two steps. During step 1 it partially breaks down into olivine and a hydrous phyllosilicate closely related to the 10 Å phase. The modal abundance of the intermediate assemblage is described by 66 wt % antigorite, 19 wt % olivine, 12 wt % 10 Å phase. During step 2 at higher temperature, the remaining antigorite and the 10 Å phase fully dehydrate. From the analysis of reaction progress data, we determined that the major release of aqueous fluid occurs during step 2 at a fast rate of 10−4 mfluid 3 mrock −3 s−1. This exceeds by orders of magnitude the typical time scale of deformation by ductile mechanisms of any mineral or rock in the subducting slab or in the overlying mantle wedge. These results suggest that the fast dehydration of antigorite may well trigger the seismicity of the lower plane of the double seismic zone

Elasticity of antigorite, seismic detection of serpentinites, and anisotropy in subduction zones

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Insights on the thermal history of the paris cm chondrite based on the phase relations of its opaque assemblages

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Creep of phyllosilicates at the onset of plate tectonics

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