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The loess–red clay sequences in northern China provide high-resolution terrestrial records of Asian monsoon evolution and aridification of the Asian interior. To date, however, aeolian deposits of late Pliocene-early Pleistocene age (3.5–2.4 Ma) have only rarely been reported from the western Chinese Loess Plateau (CLP), which significantly hinders our understanding of the distribution of aeolian deposits and the palaeoenvironmental evolution of the region. Here, we present magnetostratigraphic, lithologic and magnetic susceptibility results for two recently-drilled boreholes from the north bank of Baxie River, central Linxia Basin, which are highly correlative with those of the loess–red clay deposits spanning the interval from 3.6 to 2.4 Ma in the eastern CLP. Our results provide the first direct evidence for the occurrence of late Pliocene-early Pleistocene aeolian deposits in the western CLP and provide new insights into the distribution of aeolian deposits in northern China. The spatial coherence of the magnetic susceptibility fluctuations further indicates that magnetic susceptibility is a powerful tool for stratigraphic correlation of late Pliocene aeolian deposits in the western CLP. In addition, our results demonstrate that erosional events may have occurred in the early or middle Pleistocene, and they may provide new insights into the reasons for the absence of loess–red clay deposits from 3.5 to 2.4 Ma in most parts of the western CLP. [ABSTRACT FROM AUTHOR]

The GICE (Guttenberg Carbon Isotope Excursion) is a positive δ13C excursion and a prominent feature of the Late Ordovician chemostratigraphic record. The GICE has been identified on different paleocontinents, and its cause is still unresolved. One explanation suggests that the GICE is the carbon isotopic expression of changes that occurred during the transition from an icehouse to greenhouse climate ~10 myr prior to the end Ordovician glaciation and mass extinction event. There are lithological and paleontological observations across this time interval that support cooling, but such evidence contradicts documented oxygen isotopic trends at low to middle latitudes that instead indicate warming during this interval.We measured neodymium isotopes, which are a weathering proxy and water mass tracer, in conodonts from the Upper Mississippi Valley to determine if changes in the global climate system might account for the lithologic and paleontologic changes observed across the GICE interval. The Nd isotopic values increase from -14.7 to -10.3 across 2 m of section up to the stratigraphic level of the Deicke K-bentonite. A decrease in εNd values occurs between the Deicke K-bentonite and the overlying Millbrig K-bentonite with values ranging from -16.2 to -18.5 across 8 m of section above the Millbrig K-bentonite. These results suggest high inputs due to weathering of proximal Precambrian shield rocks with lower εNd values high in the section, reflecting a regression (consistent with glacial growth) between the Millbrig and Deicke K-bentonites. However, a documented decrease in δ18O values in the study area and stratigraphic evidence for a regional transgression conflict with scenarios invoking glaciation and regression at this time. Local tectonic quiescence during the GICE also precludes a tectonically driven regression as a source of increased nonradiogenic εNd weathering flux. Therefore, the decrease in εNd values in this stratigraphic interval is suggested to result from increased weathering rates driven by global climatic change and/or circulation changes that increased input of a nonradiogenic signature to the region. These findings imply that using εNd as a direct proxy for eustatic changes, as suggested in previous work, is complicated during periods of changing climate and weathering fluxes. [ABSTRACT FROM AUTHOR]

Changes in large mammal population and biotic regionalism of the Italian Peninsula during Upper Pleistocene have been well documented over the last twenty years. On the other hand, only few studies have focused on the changes in small mammal fossil assemblages. Grotta Paglicci is a key archaeological site for Italian prehistory. It is well dated and it shows an uninterrupted chronological sequence of Upper Palaeolithic lithic industries, ranging from the Aurignacian to the Late Epigravettian. Small mammal remains from the Upper Palaeolithic layers of this cave have been identified and the assemblage has been analysed through the application of Simpson diversity index, Habitat Weighting and Bioclimatic model methods. The results show remarkable differences through the record: major climatic changes (GS2 is particularly well defined) are visible and a clear turning point is observable at the Bølling-Allerød interstadial transition. This is in line with environmental and climatic oscillations already detected in the Italian Peninsula. These data also suggest that a strong regionalism characterized the south-eastern Italian Peninsula during the Late Pleistocene. [ABSTRACT FROM AUTHOR]

A megaslump at Batagaika, in northern Yakutia, exposes a remarkable stratigraphic sequence of permafrost deposits ~50–80 m thick. To determine their potential for answering key questions about Quaternary environmental and climatic change in northeast Siberia, we carried out a reconnaissance study of their cryostratigraphy and paleoecology, supported by four rangefinder 14C ages. The sequence includes two ice complexes separated by a unit of fine sand containing narrow syngenetic ice wedges and multiple paleosols. Overall, the sequence developed as permafrost grew syngenetically through an eolian sand sheet aggrading on a hillslope. Wood remains occur in two forest beds, each associated with a reddened weathering horizon. The lower bed contains high amounts of Larix pollen (>20%), plus small amounts of Picea and Pinus pumila, and is attributed to interglacial conditions. Pollen from the overlying sequence is dominated by herbaceous taxa (~70%–80%) attributed to an open tundra landscape during interstadial climatic conditions. Of three hypothetical age schemes considered, we tentatively attribute much of the Batagaika sequence to Marine Oxygen Isotope Stage (MIS) 3. The upper and lower forest beds may represent a mid–MIS 3 optimum and MIS 5, respectively, although we cannot discount alternative attributions to MIS 5 and 7. [ABSTRACT FROM AUTHOR]

The late Pliocene–early Pleistocene Tosunlar succession (Denizli Basin, southwestern Turkey) represents fluvial-dominated delta environments at the margins of a brackish long-lived lake. Two main facies associations are documented: (i) a delta front facies association, with a distal (DF1) and proximal (DF2) deposits; and (ii) a delta plain facies association that contains distributary channel (DP1) and interdistributary swamp (DP2) deposits. The stable isotopic analysis of the mollusc faunas exhibit a narrow range of values (–4.68 < δ 18 O < + 0.21‰ and + 0.43 < δ 13 C < + 3.27‰, respectively) and the very poor δ 18 O–δ 13 C correlation (r = − 0.16) may indicate hydrologically open lake and significant diagenetic alteration. The mollusc faunas and their stable isotope ratios show a biogeographically isolated brackish lake system under semiarid climatic conditions. Under special environmental conditions the endemic faunal composition remained constant which is very unusual for a (semi-) isolated long-lived lake setting. [ABSTRACT FROM AUTHOR]

L’Arbreda Cave is one of the southernmost of the Reclau Caves (Serinyà, Girona, northeastern Iberian Peninsula), located between the west margin of the Pla d’Usall and the Serinyadell river, at an altitude of about 211 m a.s.l. The Pla d’Usall forms part of the Banyoles-Besalú Basin, which is bounded by Eocene and Neogene reliefs. It is filled with sediments of Plio-Pleistocene age. The cave is a shelter formed by travertine cascades with a degree of karstification, and contains sedimentary deposits ranging from the end of the Middle Pleistocene to the Early Holocene, thus constituting an important archaeo-palaeontological record for an understanding of the prehistoric occupation of northeastern Iberia. It is one of the most complete and best-dated terrestrial sequences in Iberia from the Mousterian to the Early Holocene period. In this paper we present a palaeoenvironmental and palaeoclimatic reconstruction of the sequence based on non-flying small mammals (insectivores and rodents) and pollen analyses. The environmental and climatic results, together with the absolute dating of the sequence and direct comparison with NorthGRIP δ 18 O and the sea-surface temperatures (SST) of the Alborán Sea, allow us to identify various climatic periods within our sequence: a cold period between interstadials 12 and 10 in Level I, probably interstadial 10 in Level H, the Last Glacial Maximum (LGM) in Levels C and B, the Bölling-Allerød interstadial (B/A) in Level A, and the Preboreal/Boreal (Pr/B) in the Terra Rossa Level. [ABSTRACT FROM AUTHOR]

Abstract: Thick lake sediments discovered in the southern part of the Czech Republic provide a high-resolution archive for detailed study of paleoenvironmental changes during the Late Pleistocene to Holocene in eastern-central Europe. Until recently, no similar records were available for this important region in the transition from oceanic to continental macro-climatic settings. Using a multi-proxy approach that combines sedimentological, pollen-analytical, paleozoological (Chironomids), geochemical and mineral-magnetic methods we demonstrate that major climatic events of the Late Glacial can be correlated with Atlantic rather than continental regimes as reported in paleoclimatic literature for the area of the interest. The sensitivity of applied biological and abiological techniques to climatically-driven processes allows trans-regional comparisons and enables us to discuss the pattern of geographic variation in these processes. We are able to establish a clear relationship between vegetation cover, soil development and erosional processes. A short-term intra-Alleröd cool event has been correlated with the Gerzensee oscillation. Proxy evidence suggests that the early half of the Younger Dryas was rather humid, whereas the latter half was dry and had significant impact on vegetation, sedimentary dynamics and lake level status during the YD/Preboreal transition. [Copyright &y& Elsevier]