We believe an explanation for this discrepancy lies in the numerous improvements in analytical technique in the intervening several decades, including improved monitoring of neutron fluence gradients in irradiation packages, and major improvements in mass resolution, sensitivity, and efficiency afforded by a new generation of multicollector mass spectrometers (e.g.the Nu Instruments Noblesse 5-collectors instrument used herein).With the notable exception of two grains that did not yield plateaus (e.g. S2n), there is no clear evidence of rising, saddle-shaped or otherwise heterogeneous release patterns that would indicate isotopic discordance.
The Late Pleistocene Campanian Ignimbrite (CI) super-eruption (Southern Italy) is the largest known volcanic event in the Mediterranean area.
The CI tephra is widely dispersed through western Eurasia and occurs in close stratigraphic association with significant palaeoclimatic and Palaeolithic cultural events.
These improved capabilities permit the adoption of single-grain incremental heating, whereas previously only single-grain total-fusion, or multi-grain step-heating approaches were possible.
Additional previous ages for the CI were obtained from both the proximal equivalent C-13 (Y-5) layer, which yielded mean ages of 39.85 ± 0.11 ka and 41.4 ± 2.1 ka, respectively (also recalculated for consistency). 2 is virtually identical to the present result, and while that of ref.
Here we present new high-precision Ar (39.85 ± 0.14 ka, 95% confidence level) dating results for the age of the CI eruption, which substantially improve upon or augment previous age determinations and permit fuller exploitation of the chronological potential of the CI tephra marker.
These results provide a robust pair of Ar ages for refining both the radiocarbon calibration curve and the Late Pleistocene time-scale at ca. In addition, these new age constraints provide compelling chronological evidence for the significance of the combined influence of the CI eruption and Heinrich Event 4 on European climate and potentially evolutionary processes of the Early Upper Palaeolithic.
In the framework of western Eurasian tephrostratigraphy, the Campanian Ignimbrite (CI, southern Italy, circa 40 ka first recognized the large dispersal of the CI by correlating on-land outcrops to the widespread Y-5 marine layer.
Interest in the eruption in the last decade has included recognition of the CI horizon in distal localities (e.g. 18) events and Palaeolithic cultural entities(a) Location of the main palaeoenvironmental records (orange dots) and Palaeolithic sites (blue dots) mentioned in the text.
Results are discussed in terms of implications for the radiocarbon calibration, late Pleistocene time-scale, and palaeoecologic and Early Palaeolithic cultural change in western Eurasia.