To determine the p-t stability of hydrous phases in ultramafic compositions in subduction zones, and the conditions at which h2o is released from subducting slabs in dehydration reactions; to obtain thermodynamic data for hydrous phases through phase-equilibrium experiments and in situ volume measurements; and to constrain the equation of state of h2o at high pressures. Reversed phase-equilibrium experiments will be conducted on reactions in the systems mgo-sio2-h2o and mgo-al2o3-sio2-h2o; thermodynamic data for hydrous phases wil be extracted from p-t postions of solid-solid reactions; positions of dehydration reactions will constrain the equation of state of h2o; volumes of phases will be measured in situ using synchrotron radiation

This dataset contains major, trace, and volatile element contents, and sulfur isotope ratio data measured in silicate glasses found in volcanic rocks from the Central American Volcanic Arc. The files have been first published as supplementary data in: Taracsák et al. (2023): Sulfur from the subducted slab dominates the sulfur budget of the mantle wedge under volcanic arcs, Earth and Planetary Science Letters, 601:117948 The data is also accessable via the following DOI: https://doi.org/10.1016/j.epsl.2022.117948

The data are from a suite of friction experiments performed on simulated gouges from the Nankai Trough (Japan). The simulated gouges were prepared by crushing cuttings of Nankai accretionary sediments collected during Integrated Ocean Drilling Program (IODP) Expedition 358. The cuttings were crushed to produce a powder (i.e. simulated gouge) with a grain size of >125 microns. These simulated gouges were sheared under a range of effective normal stress (10-75 Mpa) and pore-fluid pressure (5-75 Mpa) conditions while the sliding velocity was stepped between 0.3 and 3 microns/s to calculated the rate-and-state friction parameter (a-b). The Nankai gouge are strongly rate-strengthening and become more rate-strengthening (i.e. more frictionally stable) at elevated pore-fluid pressure. In contrast, varying the effective normal stress has minimal effect on the frictional stability of the gouges.

Complete major and trace element analyses of all samples investigated under project component chalcophile element processing beneath arc volcanic systems, within NE/M000427/1 (see Cox et al., EPSL, 2019 https://doi.org/10.1016/j.epsl.2019.06.017 and Cox et al., Geology, 2020 https://doi.org/10.1130/G47562.1). Samples include an extensive dataset from Antuco volcano, Chile, and further analyses of young volcanic rocks from multiple Chilean stratovolcanoes and monogenetic centres. Standard data are also provided.

This Excel spreadsheet provides the composition of volcanic glasses (melt inclusions, melt embayment and matrix glasses) analysed as part of NSF-NERC grant "Sulfur Cycling in Subduction Zones". In the spreadsheet is a "readme" worksheet that explains each column and the method of data collection if applicable. These data will be included in future publications. The samples are taken from Central America, Alaska and Northern Mariana Islands.

The thermal state of marine sediments controls a range of potential dehydration reactions as sediments are subducted. In thick sediment sections it is possible that reactions that would normally occur within a subduction zone start offshore of the deformation front. This scenario may be occurring at the Sumatra subduction zone (e.g. Geersen et al., 2013; Huepers et al., 2017). We have investigated this possibility by modelling the thermal and depth history of sediments offshore Sumatra. We have used a range of different assumptions about how the sediments decompact with depth, as well as testing the dependence on the seismic velocities used for depth conversion of the horizons.

These data contain the shear modulus and attenuation of Vermont antigorite serpentinite in the seismic "low" frequency range, as functions of oscillation period (ranging from 1 to 1000s) and temperature during staged cooling from 550 degrees C down to room temperature, at a confining pressure of 200 MPa. This dataset is used and fully described/interpreted in the paper: David, E.C., N. Brantut, L.N. Hansen and I. Jackson, Low-frequency measurements of seismic velocity and attenuation in antigorite serpentinite, submitted to Geophys. Res. Lett.

Data from the IODP Expedition will be archived by the International Ocean Discovery Program, including all data generated during the shipboard palaeomagnetic and magnetic anisotropy analyses and all of the logging data (FMS tool, GBM data), plus associated explanatory notes. Shore based palaeomagnetic and magnetic anisotropy data, FMS---based reorientation parameters, and downhole magnetizations inferred from modelling of the GBM borehole magnetometer data will be made available to the international community via appropriate IODP Data Reports (in addition to primary journal articles). Data Includes: Shipboard cryogenic magnetometer data Shipboard and shore based discrete sample remanence data Shipboard and shore based magnetic anisotropy data FMS---based reorientation parameters Magnetic parameters modelled using borehole magnetometer data

Porewaters from IODP Expedition 366 were extracted from serpentinite mud volcano sediments onboard the RV JOIDES Resolution (see Fryer et al, 2017; 2018 for details). Selected samples were then analysed at the University of Southampton for 87Sr/86Sr and boron isotopes and SUERC for stable hydrogen and oxygen isotope data. The strontium isotope data has recently been accepted for publication (Albers et al., 2019 (In Press) Fluid–rock interactions in the shallow Mariana forearc: carbon cycling and redox conditions, Solid Earth special issue "Exploring new frontiers in fluids processes in subduction zones").