Dating of carbonate covering cave paintings at peruaçu, Brazil by TL and EPR methods.

Appl Radiat Isot

Instituto de Física, Universidade de São Paulo, Rua do Matão, Travessa R, 187, CEP 05508-090, São Paulo, SP, Brazil.

Published: November 2019

In the present work, carbonate samples covering wall painting of four points in the same site found at Peruaçu National Park in the extreme northwest of the state of Minas Gerais, Brazil, has been investigated and dated by thermoluminescence (TL) and electron paramagnetic resonance (EPR) techniques. The EPR spectrum of the carbonate samples presented the typical six signals due to Mn ion and signals around g~2.0 due to SO and CO. The thermal stability and dose response of the EPR signals were found to be suitable for an age determination using the center due to CO. The carbonate sample exhibits TL peaks at approximately 350 °C. TL and EPR dating of the carbonate samples that covered the cave paintings gave an age of 33.13 to 48.40 ka. This series of dating data indicate that in the region about 220-250 km from the coast and extending from the State of Piaui, Bahia to Minas Gerais people lived around 50000 years ago.

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http://dx.doi.org/10.1016/j.apradiso.2019.108847DOI Listing

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