THE MARINE RESERVOIR EFFECT: A CASE STUDY OF ARCHAEOLOGICAL SITES AT GUANABARA BAY, RIO DE JANEIRO, BRAZIL

This study applied, radiocarbon dating to charcoal and mollusk samples from Sernambetiba and Amourins archaeological sites in the Northeast region of Guanabara Bay, in the state of Rio de Janeiro, Brazil, to assess the marine radiocarbon reservoir effect (MRE) of this area, being applied for the correction of the marine samples ages. The results for this estuarine system were Delta R = -87 +/- 90 C-14 yr and Delta R = -244 +/- 70 C-14 yr for 3970 +/- 70 C-14 yr BP and 2357 +/- 60 C-14 yr BP, respectively. Based on these findings, calibrated C-14 ages were calculated for Sernambetiba and Amourins shell mound sites surrounding the bay. Marine samples from the Guapi site were analyzed and only their radiocarbon ages presented because there were no paired terrestrial samples for the MRE assessment. These results are coherent with previously published values also derived from archaeological samples for the Rio de Janeiro state coastal region and contribute to the interpretation of human occupation of the region during the Holocene.