serpentinization; mass transfer; fluid/rock interactions; mid-ocean ridges; experimental petrology; hydrothermal circulation; kinetics; fluid pathways; numerical modelling
Picazo Suzanne, Malvoisin Benjamin, Baumgartner Lukas, Bouvier Anne-Sophie (2020), Low Temperature Serpentinite Replacement by Carbonates during Seawater Influx in the Newfoundland Margin, in Minerals
, 10(2), 184-184.
Malvoisin Benjamin, Mazzini Adriano, Miller Stephen A. (2018), Deep hydrothermal activity driving the Lusi mud eruption, in Earth and Planetary Science Letters
, 497, 42-49.
Benjamin Malvoisin Nicolas Brantut Mary-Alix Kaczmarek (2017), Control of serpentinisation rate by reaction-induced cracking, in Earth and Planetary Science Letters
, 476, 143-152.
Omlin Samuel, Malvoisin Benjamin, Podladchikov Yury Y. (2017), Pore Fluid Extraction by Reactive Solitary Waves in 3-DReactive Porosity Waves, in Geophysical Research Letters
, 44(18), 9267-9275.
MalvoisinBenjamin, AustrheimHaakon, HetényiGyörgy, ReynesJulien, HermannJoerg, BaumgartnerLukas, PodladchikovYuri, Sustainable densification of the deep crust, in Geology
Supplementary material for "Measurement of volume change and mass transfer during serpentinisation: insights from the Oman Drilling Project" (JGR Solid Earth)
|Persistent Identifier (PID)
The three supplementary files include one figure displaying the results of X-ray microtomography (File S1), two compilations of figures dealing with the volume change measurement (Files S2 and S3) and a table with the measured compositions in major and trace elements (Table S1).File S1 (Malvoisin_ds01.pdf). Result of X-ray microtomography. Olivine and Fe-brucite have a similar attenuation. The grains segmented by selecting this attenuation are displayed with a circle with a size proportional to the radius of a sphere of equivalent volume. The color of each circle depends on e, the aspect ratio (ratio of the length of the minimum and maximum axes of an ellipsoid fitted to each grain). The white arrow indicates the location of the main central vein. Grains near the main central vein have a lower e attributed to the platy habitus of Fe-brucite. The other grains are considered as olivine and used for the calculation of the extent of reaction.File S2 (Malvoisin_ds02.pdf). Optical photomicrographs used to calculate volume change during reaction (see main text for details about the calculation). Olivine grains (white) are surrounded by the serpentine + brucite mixture (light green to yellowish). The magnetite/clinopyroxene platelets are mapped in blue in olivine and in red in the serpentine + brucite mixture. The results of the model fitting the best the average orientation of the platelets in olivine are shown in green. The title of each photomicrograph provides the minimum and maximum estimates for volume change calculated with this model (see details about the calculation in the main text), and the size of the bottom right scale bar.File S3 (Malvoisin_ds03.pdf). Histograms of magnetite/clinopyroxene platelet orientation (in degree). Each histogram corresponds to a photomicrograph of File S1. The order of the histograms and the photomicrographs is the same. The orientations in the olivine grains, the serpentine + brucite mixture and for the model fitting the best the average orientation in olivine are displayed in blue, red and green, respectively. The title of the histograms provides the standard deviation of the platelet orientation in the olivine grains (STDoli), the serpentine + brucite mixture (STDori) and calculated with the model fitting the best the orientation in olivine (STDcal).Table S1 (Malvoisin_ds01.xlsx). Composition in major and trace elements measured with LA-ICPMS along five profiles perpendicular to the main vein. The composition as a function of the distance to the main vein is provided. The name of the tabs indicates if the profile was acquired in spot or in continuous mode (the two modes are described in the main text).
Mantle rocks (peridotites) exhumed along large faults at slow-spreading ridges react with seawater, through hydrothermal circulation to form hydrated minerals of the serpentine group (serpentinization). This reaction strongly modifies the chemical and physical properties of the lithosphere and thus plays a key role on the geodynamics of mid-ocean ridges. Laboratory experiments on powders indicate that serpentinization should reach completion in several years, while samples recovered at mid-ocean ridges are generally incompletely serpentinized after more than tens of thousands years of seawater exposure. Explaining this discrepancy remains a challenge because it requires modelling the complex (and coupled) processes of reaction, fluid transport and deformation during serpentinization. This project aims at studying these couplings to quantify the rate of the reaction, and to model the consequences of serpentinization on fluid flow at mid-ocean ridges. An integrated approach combining innovative experiments, new numerical models and cutting-edge analytical techniques will be used at the University of Lausanne (Institute of Earth Sciences). Hydrothermal experiments will be conducted to set up a numerical model coupling reaction, fluid flow and deformation. The expected results of this project will be useful not only for academic research through better modelling of the physical and chemical changes occurring in the oceanic lithosphere but also for society with a better assessment of abiotic hydrogen production at mid-ocean ridges and CO2 sequestration capacities in peridotites. Moreover, the experimental and numerical developments performed during this project can serve as a basis for modelling other reactions in geological environments where the couplings between reaction, fluid flow and deformation play a key role. The strong national and international collaborations proposed in this project will also contribute to the high visibility of the results within the Geoscience community.