Résumé
The crystallographic preferred orientation (CPO) of olivine, pyroxenes, spinel, and amphibole was measured in 17 selected samples using a JEOL JSM 5600 at the Geosciences Montpellier EBSD facility, with 17 kV acceleration voltage and 24 mm working distance. For each thin section, CPO maps covered areas of 4 to 13 cm2 with a grid step of 15 or 35 µm, depending on olivine minimum grain size. Because of the large size of olivine porphyroclasts in most samples, CPO were measured on several thin sections and then combined. Higher-resolution CPO maps (grid step 0.5 to 10 µm depending on the dominant grain size) of fine-grained zones were also obtained for 7 samples using the CamScan Crystal Probe X500-FEG SEM, also at the Geosciences Montpellier EBSD facility. Post-acquisition treatment consisted in deleting wild spikes and filling non-indexed pixels with ≥ 6 neighbors with coherent orientations with their average orientation. In situ major element concentrations of amphiboles were measured using a Cameca SX-100 electron microprobe (CAMPARIS service, Paris). The accelerating voltage was fixed at 15 kV and beam current at 10 nA. The spot size was 1μm. Counting times were 10 s. Compositions are presented in TableS3.