Serpentinization processes occur at geological settings notably during oceanic subduction and 32 obduction, where mantle rocks interact with water. Different types of serpentine minerals form 33 according to temperature and pressure conditions, and potentially chemical exchanges. Therefore, the 34 characterization of serpentine minerals, and the possible occurrence of multiple serpentine 35 generations in mantle rocks provide essential constraints on the conditions of fluid-rock interactions 36 in the mantle. The serpentinite sole of the Peridotite Nappe of New Caledonia (Southwest Pacific) is 37 the result of several superimposed serpentinisation events. The latter were discriminated using 38 mineralogical and geochemical approaches and modeling. 39Lizardite represents more than 80% of the entire serpentine content of the ophiolite. It is 40 crosscut by several veins of other serpentine species in the serpentinite sole. The relative chronology 41 appears as follows: lizardite 1 → lizardite 2 → antigorite → chrysotile → polygonal serpentine. The 42 transition from primary/magmatic minerals to lizardite 1 is almost isochemical. Then, the 43 development of lizardite 2 yields an enrichment in fluid-mobile elements such as Cs, Rb, Ba, U and 44 light rare-earth elements and an apparent increase of the Fe 3+ /FeT ratio. The modeling of δ 18 O values 45 (1.9‰ to 13.9‰) and δD values (88‰ to 106‰) of all serpentine species through Monte-Carlo 46 simulations show that New Caledonia serpentines were mainly formed in equilibrium with fluids 47 released by the dehydration of altered oceanic crust (AOC) during subduction between 250°C and 48 350°C. AOC-derived fluids are not the unique source of fluids since a low temperature (100-150°C) 49 meteoric component is also predicted by the models. Thus, serpentine acts as a tape-recorder of fluid-50 rock interactions into the mantle from depth to (sub-)surface. 51 52 assumed to be one of the most efficient ways to recycle water and fluid-mobile elements (FME) into 67 the deeper mantle (
