Size and style of the Gondwana late Paleozoic ice cover: Insights from U-Pb dating of the Tarija Formation granitic boulders

Two granitic boulders from the Pennsylvanian Tarija Formation were sampled in order to perform laboratory analyses to define their possible provenance. This formation, deposited during the Late Paleozoic ice age (LPIA), represents the climax of glacial-related sedimentation in the Tarija Basin. The boulders were collected from massive diamictite levels in the Cerro Piedras locality, in Eastern Cordillera. Zircons concentrated from these boulders yield Precambrian U-Pb ages. One of the obtained dates has a Concordia Age of 2068.97 ± 6.06 Ma, indicating a crystallization in Paleoproterozoic times.