Marine Carbon Reservoir Age Estimates for the Far South Coast of Peru

Abstract

In order to estimate the apparent age of seawater (R) and the corresponding local offset from the global marine radiocarbon calibration curve (δR) on the far south coast of Peru for 2 periods in the past, 6 pairs of associated marine shell and unburned wood samples from archaeological excavations at Loreto Viejo were 14 C dated. Three pairs from about cal AD 1280–1380 indicated larger and more variable δR estimates than have been obtained for other periods in nearby regions, suggesting that δR may vary considerably over space and/or time. Three pairs from about 1870–1680 cal BC yielded consistent shell dates, but only one reasonable terrestrial date and δR estimate, probably due to stratigraphic mixing in antiquity. The one early δR estimate falls slightly outside the range of the later ones, suggesting either still greater spatial variability in δR, or some temporal variability.