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In the Basilicata region, located in southern Italy and known for hosting among the first occurrences of the Acheulean culture in southwestern Europe, the Lower Paleolithic site of Loreto at Venosa is located less than a kilometer from the emblematic site of Notarchirico and less than 25 km from Cimitero di Atella. The Loreto site has not been studied as thoroughly as the two other sites and, although geological investigations have been carried out in the Venosa basin, no direct numerical dating has ever been published for the three archaeological levels brought to light during the excavation campaigns. We present a multi-method geochronological approach combining ESR/U-series, ESR, and 40Ar/39Ar permitting to refine the age of the most ancient archaeological level (A) of the Loreto site. These data allow us to propose an MIS 13 age for this level, in accordance with previous hypotheses based on geological and paleontological data. We also propose a technical review of the lithic tools preserved in the collection of the National Archaeological Museum of Venosa to integrate Loreto in the evolution scheme of the European Acheulean techno-complex emergence and diffusion. [ABSTRACT FROM AUTHOR]

A 230Th/U-dated stalagmite from Hulu Cave was analyzed for δ18O, δ13C, and trace elements. A ~10-yr-resolution δ18O record, spanning 51.7–42.6 ka, revealed Dansgaard-Oeschger (DO) events 14 to 11. A similar rapid transition and synchronous timing of the onset of DO 12 is evident between the Greenland and Hulu Cave records, which suggests a common forcing mechanism of DO cycles in the North Atlantic and monsoonal region of Asia. Centennial-scale monsoonal oscillations in the cave δ18O record are indicative of hydroclimatic instability during interstadials. After removing the signals of remote moisture sources, the proportion of moisture from nearby sources is found to be higher during stadials than during interstadials. To explain this, we propose that the movement of the westerly jet is an important control on the balance of nearby and distant moisture sources in East Asia. In addition, the records of δ13C and trace element ratios, which are proxies of local environmental changes, resemble the δ18O record on the scale of DO cycles, as well as on even shorter timescales. This suggests that hydrological processes and biological activity at the cave site respond sensitively to the monsoonal changes. [ABSTRACT FROM AUTHOR]

A precisely 230Th-dated stalagmite δ13C profile from Hulu Cave, China, is presented to characterize the frequency and pattern of millennial-scale Asian monsoon (AM) variability from 160.6 to 132.5 ka. Evidence for an antiphased relationship of the δ13C and δ18O on the millennial scale suggests that the δ13C is indicative of the local hydrological cycle associated with changes in AM strength. Owing to the δ13C responding to AM changes more sensitively than the δ18O, we could identify 15 strong AM events that correlate to cold intervals recorded in Antarctic ice cores within 230Th dating uncertainty. This result supports a dynamic link of AM strength and southern hemispheric climates via the cross-equatorial airflows. Power spectrum analysis shows a predominant periodicity of 1.5–2.5 ka for the δ13C profile, similar to the Dansgaard-Oeschger frequency during the last glacial period. Moreover, the AM events are characterized by rapid transitions at the onset, suggesting that the observed millennial-scale AM variability is likely forced by northern high-latitude climates via north–south shifts of the Intertropical Convergence Zone associated with the bipolar seesaw mechanism. As evidence for a common mechanism for ice age terminations, a strong AM event (~134 ka) surrounding Termination II is analogous to the Bølling-Allerød warming interval. [ABSTRACT FROM AUTHOR]

We present two isotopic (δ 18 O and δ 13 C) sequences of a twin-stalagmite from Zhuliuping Cave, southwestern China, with 230 Th dates from 14.6 to 4.6 ka. The stalagmite δ 18 O record characterizes orbital- to decadal-scale variability of Asian summer monsoon (ASM) intensity, with the Holocene optimum period (HOP) between 9.8 and 6.8 ka BP which is reinforced by its co-varying δ 13 C data. The large multi-decadal scale amplitude of the cave δ 18 O indicates its high sensitivity to climate change. Four centennial-scale weak ASM events during the early Holocene are centered at 11.2, 10.8, 9.1 and 8.2 ka. They can be correlated to cold periods in the northern high latitudes, possibly resulting from rapid dynamics of atmospheric circulation associated with North Atlantic cooling. The 8.2 ka event has an amplitude more than two-thirds that of the Younger Dryas (YD), and is significantly stronger than other cave records in the Asia monsoon region, likely indicating a more severe dry climate condition at the cave site. At the end of the YD event, the δ 13 C record lags the δ 18 O record by 300–500 yr, suggesting a multi-centennial slow response of vegetation and soil processes to monsoon enhancement. [ABSTRACT FROM AUTHOR]

Abstract: The combined U-series/electron spin resonance (ESR) dating method was applied to nine teeth from two Early Pleistocene archaeological sites located in the Orce area (Guadix-Baza Basin, Southern Spain): Fuente Nueva-3 (FN-3) and Barranco León (BL). The combination of biostratigraphy and magnetostratigraphy places both sites between the Olduvai and Jaramillo subchrons (1.78–1.07Ma). Our results highlight the difficulty of dating such old sites and point out the limits of the combined U-series/ESR dating method based on the US model. We identified several sources of uncertainties that may lead to inaccurate age estimates. Seven samples could not be dated because the dental tissues had (230Th/234U) activity ratios higher than equilibrium, indicating that uranium had probably leached from these tissues. It was however possible to calculate numerical estimates for two of the teeth, both from FN-3. One yielded a Middle Pleistocene age that seems to be strongly underestimated; the other provided an age of 1.19±0.21Ma, in agreement with data obtained from independent methods. The latter result gives encouragement that there are samples that can be used for routine dating of old sites. [Copyright &y& Elsevier]