CROSS-DATING (Th/U-14C) OF CALCITE COVERING PREHISTORIC PAINTINGS AT SERRA DA CAPIVARA NATIONAL PARK, PIAUI, BRAZIL

The question of when the first humans arrived in the New World has been a bone of contention for several decades. Similarly, the age of rock paintings has been heatedly debated. Settlements in the Serra da Capivara National Park have been dated to between 5 kyr and >50 kyr, which is far older than the Clovis barrier. Moreover, calcite formation on a rock-wall painting in a rockshelter yielded thermoluminescence (TL) and electron paramagnetic resonance (EPR) ages older than 35 kyr BP (Watanabe et al. 2003). In an attempt to contribute to this ongoing debate, we have studied calcite deposits covering prehistoric paintings from several rockshelters (Toca da Bastiana, Toca do Serrote de Moendas, and Toca da Gameleirinha [Pedra pintada]). Coupled AMS (accelerator mass spectrometry) C-14 and MC-ICPMS (multi-collector inductively coupled plasma mass spectrometry) Th-230/U dating was performed in Toca da Gameleirinha. The ages obtained for these calcites are younger than 12 kyr and suggest that the paintings could be more recent than proposed by previous studies.