Limits...
New luminescence ages for the Galería Complex archaeological site: resolving chronological uncertainties on the acheulean record of the Sierra de Atapuerca, northern Spain.

Demuro M, Arnold LJ, Parés JM, Pérez-González A, Ortega AI, Arsuaga JL, Bermúdez de Castro JM, Carbonell E - PLoS ONE (2014)

Bottom Line: For the majority of samples dated, however, the new luminescence ages are significantly (∼50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits.Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ∼100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site.Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences.

View Article: PubMed Central - PubMed

Affiliation: Institute for Photonics and Advanced Sensing, School of Chemistry and Physics, The University of Adelaide, Adelaide, Australia; Centro Nacional de Investigación sobre la Evolución Humana, Burgos, Spain.

ABSTRACT
The archaeological karstic infill site of Galería Complex, located within the Atapuerca system (Spain), has produced a large faunal and archaeological record (Homo sp. aff. heidelbergensis fossils and Mode II lithic artefacts) belonging to the Middle Pleistocene. Extended-range luminescence dating techniques, namely post-infrared infrared stimulated luminescence (pIR-IR) dating of K-feldspars and thermally transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains, were applied to fossil-bearing sediments at Galería. The luminescence dating results are in good agreement with published chronologies derived using alternative radiometric dating methods (i.e., ESR and U-series dating of bracketing speleothems and combined ESR/U-series dating of herbivore teeth), as well as biochronology and palaeoenvironmental reconstructions inferred from proxy records (e.g., pollen data). For the majority of samples dated, however, the new luminescence ages are significantly (∼50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits. The luminescence ages obtained indicate that the top of the basal sterile sands (GIb) at Galería have an age of up to ∼370 thousand years (ka), while the lowermost sub-unit containing Mode II Acheulean lithics (base of unit GIIa) was deposited during MIS 9 (mean age = 313±14 ka; n = 4). The overlying units GIIb-GIV, which contain the richest archaeopalaeontological remains, were deposited during late MIS 8 or early MIS 7 (∼240 ka). Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ∼100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site. Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences.

Show MeSH

Related in: MedlinePlus

Radial plots showing pIR-IR225 De distributions of representative Galería samples.See Figure S5 in File S1 for the De datasets of all other samples.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4206284&req=5

pone-0110169-g006: Radial plots showing pIR-IR225 De distributions of representative Galería samples.See Figure S5 in File S1 for the De datasets of all other samples.

Mentions: The pIR-IR225 De distributions are shown in Figure 6 and Figure S5 in File S1. The majority of these De datasets cover a narrow range and all are normally distributed when assessed using a log weighted skewness test (Table 5). The pIR-IR225 overdispersion values are generally low (<10% at 1σ; Table 5) and are consistent at 2σ with the mean value of 5±1% obtained for well-bleached, unmixed samples elsewhere at Atapuerca [47]. These De characteristics suggest that any dose dispersion originating from extrinsic or intrinsic sources, including partial bleaching, are relatively insignificant in relation to the size of the measurement uncertainties. As such, we have derived the final pIR-IR225 burial doses estimates using the weighted mean (CAM) De values (Table 5).


New luminescence ages for the Galería Complex archaeological site: resolving chronological uncertainties on the acheulean record of the Sierra de Atapuerca, northern Spain.

Demuro M, Arnold LJ, Parés JM, Pérez-González A, Ortega AI, Arsuaga JL, Bermúdez de Castro JM, Carbonell E - PLoS ONE (2014)

Radial plots showing pIR-IR225 De distributions of representative Galería samples.See Figure S5 in File S1 for the De datasets of all other samples.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4206284&req=5

pone-0110169-g006: Radial plots showing pIR-IR225 De distributions of representative Galería samples.See Figure S5 in File S1 for the De datasets of all other samples.
Mentions: The pIR-IR225 De distributions are shown in Figure 6 and Figure S5 in File S1. The majority of these De datasets cover a narrow range and all are normally distributed when assessed using a log weighted skewness test (Table 5). The pIR-IR225 overdispersion values are generally low (<10% at 1σ; Table 5) and are consistent at 2σ with the mean value of 5±1% obtained for well-bleached, unmixed samples elsewhere at Atapuerca [47]. These De characteristics suggest that any dose dispersion originating from extrinsic or intrinsic sources, including partial bleaching, are relatively insignificant in relation to the size of the measurement uncertainties. As such, we have derived the final pIR-IR225 burial doses estimates using the weighted mean (CAM) De values (Table 5).

Bottom Line: For the majority of samples dated, however, the new luminescence ages are significantly (∼50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits.Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ∼100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site.Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences.

View Article: PubMed Central - PubMed

Affiliation: Institute for Photonics and Advanced Sensing, School of Chemistry and Physics, The University of Adelaide, Adelaide, Australia; Centro Nacional de Investigación sobre la Evolución Humana, Burgos, Spain.

ABSTRACT
The archaeological karstic infill site of Galería Complex, located within the Atapuerca system (Spain), has produced a large faunal and archaeological record (Homo sp. aff. heidelbergensis fossils and Mode II lithic artefacts) belonging to the Middle Pleistocene. Extended-range luminescence dating techniques, namely post-infrared infrared stimulated luminescence (pIR-IR) dating of K-feldspars and thermally transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains, were applied to fossil-bearing sediments at Galería. The luminescence dating results are in good agreement with published chronologies derived using alternative radiometric dating methods (i.e., ESR and U-series dating of bracketing speleothems and combined ESR/U-series dating of herbivore teeth), as well as biochronology and palaeoenvironmental reconstructions inferred from proxy records (e.g., pollen data). For the majority of samples dated, however, the new luminescence ages are significantly (∼50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits. The luminescence ages obtained indicate that the top of the basal sterile sands (GIb) at Galería have an age of up to ∼370 thousand years (ka), while the lowermost sub-unit containing Mode II Acheulean lithics (base of unit GIIa) was deposited during MIS 9 (mean age = 313±14 ka; n = 4). The overlying units GIIb-GIV, which contain the richest archaeopalaeontological remains, were deposited during late MIS 8 or early MIS 7 (∼240 ka). Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ∼100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site. Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences.

Show MeSH
Related in: MedlinePlus