The formation process of a paleoindian open-air site in Central Brazil: integrating lithic analysis, radiocarbon and luminescence dating

Luminescence characteristics of quartz from Brazilian sediments and constraints for OSL dating

“…Bioturbated horizons should also be avoided to obtain ages of sediment deposition as roots and animals can mix surface grains exposed to sunlight with grains buried during sedimentation. Despite sometimes are difficult to recognize a bioturbated deposit, OSL dating has been used to recognize post-depositional disturbance (Bateman et al 2007, Bueno et al 2012. The influence radius of gamma radiation from natural radionuclides is about 30 cm in sediments.…”

“…In those cases, aliquots with few grains or even single grains should be measured to avoid insufficiently bleached grains. Linear modulated OSL on singlegrains measurements were performed to analyze partial bleaching and post-depositional disturbance on archeological sites at central Brazil by Feathers et al (2010) and Bueno et al (2012). The authors concluded that post-depositional disturbance is the main factor responsible for higher scatter of estimated dose distributions.…”

“…Hundreds to thousands of luminescence dating surveys have been performed in Quaternary sediments from Australia, Europe and United States. Despite the huge continental and coastal Quaternary sedimentary record in Brazil, only few dating studies have been performed during the last decades (Poupeau et al 1984, 1988, Suguio et al 1999, Barreto et al 2001, Teeuw and Rhodes 2004Giannini et al 2007, Araujo et al 2008, Sawakuchi et al 2008, Tatumi et al 2008, Tsoar et al 2009, Feathers et al 2010, Sallun and Suguio 2010, Soares et al 2010, Bueno et al 2012. However, luminescence dating has limitations regarding laboratory procedures and sediment characteristics.…”

“…However, luminescence dating has limitations regarding laboratory procedures and sediment characteristics. Using data from single-grain dating of quartz Araujo et al (2008), Feathers et al (2010 and Bueno et al (2012) make considerations regarding the integrity of archeological sites at central Brazil to validate radiocarbon dates. However, still lack information regarding the luminescence behavior of the quartz found in Brazilian sediments and its suitability for radiation dose estimates using the SAR protocol.…”

Idades de deposição dos sedimentos da falésia de Itaguaré (Bertioga-SP) determinadas por luminescência opticamente estimulada

“…Dada à ausência de material orgânico sindeposicional, o método mais apropriado para a obtenção da idade do depósito é a Luminescência Opticamente Estimulada (LOE). O método de datação por LOE vem sendo amplamente utilizado, com sucesso, na última década em sedimentos continentais e costeiros no Brasil (Giannini et al 2007, Araujo et al 2008, Sawakuchi et al 2008, Tatumi et al 2008, Tsoar et al 2009, Feathers et al 2010, Sallun & Suguio 2010, Soares et al 2010, Guedes et al 2011, Bueno et al 2012. Nos últimos anos, com a aplicação do protocolo Single Aliquot Regeneration-dose (SAR), os resultados passaram a apresentar alta confiabilidade, com validação por diversos testes intrínsecos ao protocolo bem como por outros métodos geocronológicos (Banerjee et al 1999, Murray & Wintle 2000, Wintle & Murray 2006.…”