Quantitative X-ray maps of composition from a chlorite, K-white mica, albite, quartz and garnet bearing thin section from a Sambagawa blueschist facies metapelite were combined with a multiequilibrium calculation method to calculate a P-T-Fe 3+ /Fe 2+-deformation map at the millimetre scale. The studied sample was chosen because elongated chlorite crystallization tails (pressure shadows) rimmed by phengite are present, which is an appropriate assemblage for the quantification of the P-T evolution. Chlorite temperature and Fe 3+ content maps were calculated by successive iterations for each pixel analysis of Fe 3+ until convergence of the four chlorite-quartz-H 2 O equilibria that can be written using the Fe-and Mg-amesite, clinchlore, daphnite and sudoite chlorite end-members. The calculated map of Fe 2+ /Fe 3+ in chlorite is in good qualitative agreement with the in situ mapping of this ratio using XANES (X-ray absorption near edge structure) techniques. The temperature map indicates that high temperature chlorite zones with low Fe 3+ contents alternate with lower temperature zones and higher Fe 3+ contents in the crystallization tail. Late fractures perpendicular to the elongation axis of the tail are filled by very low temperature chlorite (<250°C) showing Fe 3+ /Fe total up to 0.4. Groups of chlorite and mica pixels were then identified based on compositional and structural criteria, and a P-Tdeformation map was calculated using representative analyses of these groups. The calculated P-Tdeformation map suggests that in contrast to chlorite, the composition of most mica did not change significantly during exhumation. Mica reequilibrated in late EW shear bands only. EW shearing was already active at 0.1 GPa, 500°C, which corresponds to the peak temperature (and probably pressure) conditions, at reduced redox conditions. The intensity of deformation probably decreased with decrease in temperature to $350-400°C. At this temperature, a second main deformation event corresponding to a further EW stretching occurred and was still active below 250°C and more oxidizing conditions. These results indicate that the scale at which P-T data can be obtained is now close to the scale of observation of structural geologists. A close link between deformation and mineral reaction is therefore possible at the microscopic scale, which provides information about the relationship between deformation and mineral reactivity, the modalities of deformation with time and the P-T conditions at which it occurred.

To better understand the extended x-ray absorption fine structure (EXAFS) spectroscopic information obtained for complex materials such as those encountered in Earth sciences, we propose to use the Continuous Cauchy Wavelet Transform (CCWT). Thanks to this method, the EXAFS spectra can be visualized in three-dimension: the wavevector (k), the interatomic distance uncorrected for phase-shifts (R') and the CCWT modulus (corresponding to the continuous decomposition of the EXAFS amplitude terms). Consequently, more straightforward qualitative interpretations of EXAFS spectra can be performed, even when spectral artifacts are present, such as multiple-scattering features, multi-electronic excitations or noise. More particularly, this method provides important information concerning the krange of each EXAFS contribution, such as next nearest-neighbors identification. To illustrate the potential of CCWT analyses applied to EXAFS spectra, we present first the experimental and theoretical spectra obtained for well-crystallized minerals, thorite and zircon, at the Th L III -, and Zr K-edges, respectively. Then, we present the CCWT analyses of EXAFS spectra collected for amorphous materials of geochemical and environmental interests, including a sodium trisilicate glass and an aqueous chloride solution, at the Mo K-,

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BM23 is the general-purpose EXAFS bending-magnet beamline at the ESRF, replacing the former BM29 beamline in the framework of the ESRF upgrade. Its mission is to serve the whole XAS user community by providing access to a basic service in addition to the many specialized instruments available at the ESRF. BM23 offers high signal-to-noise ratio EXAFS in a large energy range (5-75 keV), continuous energy scanning for quick-EXAFS on the second timescale and a micro-XAS station delivering a spot size of 4 mm  4 mm FWHM. It is a user-friendly facility featuring a high degree of automation, online EXAFS data reduction and a flexible sample environment.