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Integration of late Quaternary continental and marine proxies allows improved reconstruction of palaeoenvironment and palaeoclimates models for the south-eastern coast of Brazil. In this paper, we analyse pollen, fern spores, and dinoflagellate cysts in a marine sediment core (GL74) over the last ∼109 kyr. Results showed that, between 109 and 89.5 kyr, low sea levels promoted the expansion of herbaceous taxa across open areas while climatic conditions were relatively warm and humid, as indicated by the high frequency of Atlantic rainforest Ombrophilous forest pollen types and abundant of fern spores. Between ∼79–49 kyr, higher concentrations of palynomorphs were recorded, which were likely related to the low relative sea level during the last glacial period. During this interval, there was a decrease in tree pollen grains and an increase in shrub and herbaceous pollen grains, indicating cold and relatively dry weather conditions. In the Holocene period, the low deposition of palynomorphs may have been influenced by the gradual submergence of the central part of the Brazilian coast. This process was associated with warm and humid climatic conditions, as suggested by the expansion of rainforests and the presence of hygrophyte/aquatic taxa and fern spores, as well as the retraction of grassland pollen types. Dinocyst assemblages suggest that nutrient-rich waters and/or the presence of upwelling cells were dominant between ∼109–88 kyr, but gradually reduced between 88 and 65 kyr (and/or ∼ 88–20 kyr) under the influence of subtropical fronts. The study culminated in the dominance of unproductive warm water in the upper column between 65 and 0.5 kyr. • Correlation of continental and marine proxies in south-eastern Brazil during the late Quaternary Late • Quaternary dynamics of the South Atlantic Ocean based on dinocysts • Reconstruction of palaeovegetation and palaeoclimate for the last ∼109 kyr along the southeast coast of Brazil [ABSTRACT FROM AUTHOR]

The Cretaceous period is a typical representative of a 'greenhouse climate' in geological periods, and is also an important period for the formation of hydrocarbon source rocks, which has become a hot spot in the study of palaeoclimate and organic matter enrichment. In order to further explore the mechanism of action between paleoclimate and organic matter enrichment, the response mechanism of organic matter enrichment to palaeotemperature and palaeorainfall is finely characterised by synthesising the analysis of sporopollen, biomarkers and n-alkane carbon isotopes in this study. The sporopollen indicates that the palaeoclimate is generally temperate, semiarid to semihumid, and the n-alkane and n-alkane carbon isotopes indicate that the palaeoclimate and palaeorainfall have obvious fluctuations and synchronous characteristics of rainfall and heat. Based on the differences in palaeotemperature and palaeorainfall, the palaeoclimate can be further divided into three stages: cool-temperate and semiarid, warm and semihumid, and cool-temperate and semiarid. The trend of palaeoatmospheric pCO 2 recovered from the carbon isotopes of normal alkanes C 27 , C 29 , and C 31 is roughly the same as that of palaeotemperature, indicating that pCO 2 is important in regulating palaeotemperature. According to the distribution pattern of organic carbon, different layers are divided into three sedimentary Units: I, II and III. Different sedimentary Units have good corresponding relationships with different palaeoclimatic stages. Under the cool-temperate and semiarid climate, lower palaeotemperature and higher palaeosalinity are not conducive to the prosperity of lake organisms. The formation of light grey mudstone, silty mudstone and carbonate has lower TOC, and the organic matter types are mostly II 1 and II. Under a warm and semihumid climate, higher palaeotemperature and moderate palaeorainfall are conducive to the prosperity of lake organisms. The formation of oil shale and shale has higher TOC, and the organic matter types are mostly I and II 1. However, excessive palaeorainfall brings much terrigenous debris, leading to the organic matter dilution. Therefore, palaeoclimate and palaeorainfall not only affect the abundance of organic matter, but also affect the types of organic matter. In the paper, the mechanism of organic matter enrichment is improved by delicately characterising the palaeotemperature and palaeorainfall. • Reconstruction of the early Cretaceous paleoclimate using n-alkanes and sporopollen in terrestrial sediments. • High precision recovery of atmospheric pCO 2 in the Early Cretaceous using carbon isotopic of n-alkanes. • Revealed the impact of paleoclimate on organic matter enrichment. [ABSTRACT FROM AUTHOR]

The environmental and climatic conditions of the Late Pleistocene of Southern Belgium are here determined for the final part of Marine Isotope Stage 3 (MIS 3) and for MIS 2 on the basis of a study of rodent assemblages. This paper provides a synthesis of several sets of environmental and climatic data from Late Pleistocene sites, all of which are located in southern Belgium. One has previously been published (Caverne Marie-Jeanne), and seven are unpublished (Cavernes de Goyet, Trou des Nutons, Trou du Frontal, Trou de Chaleux, Grotte la Chefalize, Trou du Chêne, and Trou du Sureau). The habitat weighting and quantified ecology methods are applied to rodent material housed in the Royal Belgian Institute of Natural Sciences (RBINS, Brussels), and previous radiocarbon dates are updated, in order to reconstruct past environments. Among all the sites under analysis, the quantified ecology method shows that Trou de Chaleux corresponds to the coldest temperatures and lowest precipitation. Trou de Chaleux, with a chronology between ca. 15,964–14,014 cal yr B.P., could probably be placed in Greenland Stadial 2 (GS2) or Heinrich Event 1 (HE1). It has a rodent assemblage associated with a predominance of open dry and rocky formations, the most abundant species being the collared lemming and the narrow-headed vole. These data are found to coincide with previous studies carried out on the large-mammal, herpetofaunal, and avifaunal associations of the site, as well as on small-mammal associations from other sites in southern Belgium with similar chronology, such as Grotte Walou. Taken together, this indicates that these latest Pleistocene intervals in southern Belgium were characterized by harsh climatic and environmental conditions. In contrast, the other assemblages under study yielded much more heterogeneous results, frequently inconsistent with an attribution to the Pleistocene. This is likely to be a result of their admixture with Holocene material due to recent intrusions. • Manuscript provides an environmentally synthesis of eight Belgian Late Pleistocene sites. • Rodent's assemblages are used to reconstruct Late Pleistocene environment and climate. • 14C dating from the analysed sites have been calibrated in other to update them. • Heinrich Event 1 has been identified with the rodent's assemblage of Trou de Chaleux. • Rodent's data fits the previous published macromammals, herpetofauna and avifauna. [ABSTRACT FROM AUTHOR]