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We present new data of the pre-Variscan, Variscan, and Alpine evolution of the pre-Silurian rocks from the Gréixer sector (La Cerdanya area, Eastern Pyrenees). Structural analysis and detailed mapping of Cambrian-Ordovician and Upper Ordovician low-grade metasediments suggest the existence of three deformational events, together with the emplacement of an hectometric-sized quartz vein and the development of thrusts zones. We compare the results with other sectors close to the study area, and suggest that they form the southern (reverse) limb of a kilometre-sized E-W-trending south-verging “D2” antiform of Variscan age. This fold was deformed by open NW-SE-trending south-verging “D3” folds with gently north-dipping limbs of unknown age—Variscan or Alpine. Moreover, microstructural analysis and the structural attitude of the D2 mesostructures suggest the existence of a pre-Upper Ordovician “D1” deformational event that only affects the Cambrian-Ordovician metasediments. By comparison with neighbouring areas, an Alpine age for quartz vein emplacement and the development of thrust zones is suggested.
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