Detrital zircon U-Pb ages of a late-Variscan Carboniferous succession associated with the Porto-Tomar shear zone (West Portugal): Provenance implications

► Detrital zircon U-Pb ages from a Variscan syn-orogenic succession. ► Different sediment facies with distinct proportion of zircon-age populations. ► Grenville-related units occurred near the Buçaco Basin. ► Important role of short delivery systems in sediment supply. ► Variscan grains limited to upper beds may be poor estimators of depositional age.