| Summary: | A pronounced increase of the atmospheric 14C concentration coeval with the Laschamp geomagnetic excursion (c.41-39 GISP2 ka B.P.) is apparent from recent studies. Furthermore, several Mediterranean records show a close stratigraphic coincidence of both geomagnetic and radiocarbon anomalies with the products of the Campanian Ignimbrite (CI) eruption, c.40 ka B.P. CI tephra occur in several archaeological sequences spanning the so-called Middle to Upper Palaeolithic (MUP) “transition” from Italy to Ukraine, and the CI sulphate signal has been recognized in the GISP2 ice-core. By using a tephrostratigraphic correlation between the Palaeolithic sequences and the radiocarbon-dated records containing the CI tephra, we show that the 14C concentration anomaly affected the earlier part of the MUP “transition”, severely altering the radiocarbon chronology of the “transition” itself. In particular, radiocarbon dates for archaeological occurrences immediately below the CI tephra give surprisingly “young” ages of 32,000-29,000 14C yr B.P. The tephrostratigraphic and the traditional 14C-based chronologies thus markedly differ in terms of absolute age, timing, and paleoclimatic correlations. As a consequence, radiocarbon - if unsupported by additional and independent time markers - is inadequate to date the latest occurrences of the Middle Palaeolithic or the earliest appearance of the Upper Palaeolithic in Europe. Worse still, the radiocarbon timescale alone generates a biased timing for the MUP “transition” and its interactions with the Late Pleistocene environmental processes.
|
|---|