A 14C age calibration curve for the last 60 ka: the Greenland-Hulu U/Th timescale and its impact on understanding the Middle to Upper Paleolithic transition in Western Eurasia

Universität zu Köln, Institut für Ur- und Frühgeschichte, Radiocarbon Laboratory, Weyertal 125, 50923 Köln, Germany.
Journal of Human Evolution (Impact Factor: 3.87). 11/2008; 55(5):772-81. DOI: 10.1016/j.jhevol.2008.08.017
Source: PubMed

ABSTRACT This paper combines the data sets available today for 14C-age calibration of the last 60 ka. By stepwise synchronization of paleoclimate signatures, each of these sets of 14C-ages is compared with the U/Th-dated Chinese Hulu Cave speleothem records, which shows global paleoclimate change in high temporal resolution. By this synchronization we have established an absolute-dated Greenland-Hulu chronological framework, against which global paleoclimate data can be referenced, extending the 14C-age calibration curve back to the limits of the radiocarbon method. Based on this new, U/Th-based Greenland(Hulu) chronology, we confirm that the radiocarbon timescale underestimates calendar ages by several thousand years during most of Oxygen Isotope Stage 3. Major atmospheric 14C variations are observed for the period of the Middle to Upper Paleolithic transition, which has significant implications for dating the demise of the last Neandertals. The early part of "the transition" (with 14C ages > 35.0 ka 14C BP) coincides with the Laschamp geomagnetic excursion. This period is characterized by highly-elevated atmospheric 14C levels. The following period ca. 35.0-32.5 ka 14C BP shows a series of distinct large-scale 14C age inversions and extended plateaus. In consequence, individual archaeological 14C dates older than 35.0 ka 14C BP can be age-calibrated with relatively high precision, while individual dates in the interval 35.0-32.5 ka 14C BP are subject to large systematic age-'distortions,' and chronologies based on large data sets will show apparent age-overlaps of up to ca. 5,000 cal years. Nevertheless, the observed variations in past 14C levels are not as extreme as previously proposed ("Middle to Upper Paleolithic dating anomaly"), and the new chronological framework leaves ample room for application of radiocarbon dating in the age-range 45.0-25.0 ka 14C BP at high temporal resolution.

Download full-text


Available from: Bernhard Paul Weninger, Aug 16, 2015
  • Source
    • "The current standard estimate of r(t) for atmospheric Northern Hemisphere organic samples is the INTCAL13 calibration curve, and it extends close to the practical limits of radiocarbon dating, 50,000 cal BP (Niu, 2013; Ramsey et al., 2013; Reimer et al., 2013; Staff, 2013). A second r(t) estimate is the CalPal-Hulu 2007 curve, which includes much of the radiometric data included in the INTCAL13 curve, using simple cubic spline interpolation between radiometric data points throughout its length (Weninger and J€ oris, 2008). We used the CalPal-Hulu 2007 curve to extend our calibration dataset from 50,001 to 59,500 cal BP. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Methodological developments and new paleoanthropological data remain jointly central to clarifying the timing and systemic interrelationships between the Middle-Upper Paleolithic (MP-UP) archaeological transition and the broadly contemporaneous anatomically modern human-archaic biological turnover. In the recently discovered cave site of Mughr el-Hamamah, Jordan, in situ flint artifacts comprise a diagnostic early Upper Paleolithic (EUP) assemblage. Unusually well-preserved charcoal from hearths and other anthropogenic features associated with the lithic material were subjected to acid-base-wet oxidation-stepped combustion (ABOx-SC) pretreatment. This article presents the ABOx-SC accelerator mass spectrometry (AMS) radiocarbon dates on nine charcoal specimens from a single palimpsest occupation layer. Date calibration was carried out using the INTCAL13 radiocarbon calibration dataset. With the bulk of the material dating to 45-39 ka cal BP (thousands of years calibrated before present), the Mughr el-Hamamah lithic artifacts reveal important differences from penecontemporaneous sites in the region, documenting greater technological variability than previously known for this time frame in the Levant. The radiocarbon data from this EUP archaeological context highlight remaining challenges for increasing chronological precision in documenting the MP-UP transition. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Journal of Human Evolution 08/2015; 85:157-173. DOI:10.1016/j.jhevol.2015.04.008 · 3.87 Impact Factor
  • Source
    • ". The laboratory protocols used by Maroto et al. (2012) include rigorous sample pre-treatment to minimize contamination of samples. For calibration the CalPal-2007-Hulu data set (Weninger and Jöris, 2008) and the CalPal software package (Weninger et al., 2008) were used. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The Arbreda Cave provides a detailed archaeological record of the Middle to Upper Palaeolithic and is a key site for studying human occupation and cultural transitions in NE Iberia. Recently, studies of lake archives and archaeological sites presented new evidence on climate changes in NE Iberia correlating with Heinrich events. It, therefore, needs to be determined whether climate signals can be identified in the cave sequence of Arbreda, and if so, whether these signals can be correlated with stratigraphic indicators suggesting the continuity or discontinuity of human occupation. We conducted a high-resolution sedimentological and geochemical study, including micromorphological investigations, to shed light on stratigraphy, processes of sediment accumulation and post-depositional alteration in the cave. Seven major sediment units were distinguished which partly correlate with archaeological levels. The lower part of the sequence including Mousterian levels J and K consists of fluvial deposits truncated by a sharp erosional disconformity between Mousterian levels J and I. Strong enrichment with phosphorus and strontium reflect zoogenic inputs. The transition from Mousterian to Archaic Aurignacian in levels I and H, respectively, is reflected by more gradual changes in colour, grain size and geochemical composition. However, a peak in potentially wind-blown particles (40–125 μm in diameter) reflects higher aeolian input, and banded microstructure suggests reworking of sediments at the interface. Both properties correlate with low density of finds suggesting low intensity of human occupation related to a dry spell. More arid conditions than during the Holocene are indicated for the Gravettian to Solutrean levels. These findings are in agreement with previous palaeoclimatic interpretations as based on palaeontological proxies. The detailed multi-proxy analyses of the sequence adds to our understanding on sediment accumulation and alteration in the Arbreda Cave. The transition from the Middle to Upper Palaeolithic probably includes a gap in human occupation. Assessing the significance and duration of this gap and correlating the climate signal requires three-dimensional reconstructions of find densities and more reliable geochronological control.
    Climate of the Past 09/2014; 10:1673–1692. DOI:10.5194/cp-10-1673-2014 · 3.48 Impact Factor
    • "5 ; Svensson et al . 2008 ; Weninger & Jöris 2008 ) . Hence , using the radiocarbon calibration curve to calibrate 14 C samples may artificially introduce age offset between the 14 C dated record and onsets of interstadials ( Fig . "
    Geological Society London Special Publications 09/2014; 398(1):95-112. DOI:10.1144/SP398.2 · 2.58 Impact Factor
Show more