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The subduction history of the Neo-Tethys is critical for understanding the early-stage tectonic evolution of the Qinghai–Tibetan Plateau. Arc volcanics, which usually record the subduction process, thus can help trace the evolution of the Neo-Tethys. In this paper, we report for the first time zircon LA-ICP-MS U-Pb ages, whole-rock major and trace element geochemistry, as well as Sr–Nd–Hf isotopic data for the volcanic rocks from the Danshiting Formation at the southern edge of the Lhasa Terrane. Two samples collected from the Danshiting Formation volcanic rocks yield zircon U-Pb ages of 97.1 ± 0.8 Ma and 90.1 ± 0.7 Ma, respectively. The volcanic rocks of the Danshiting Formation are composed dominantly of basalts and andesites characterized by depletion of high-field-strength elements, low (87Sr/86Sr)i ratios (0.7042–0.7045), high eNd(t) (+2.1 to +2.7) and high eHf(t) values (mean + 11.6). These rocks show geochemical affinity of arc volcanic rocks. The volcanic rocks of the Danshiting Formation may have formed during the northward subduction of the Neo-Tethys. This paper, combined with the previous data, briefly divide the northward subduction of the Neo-Tethys into four periods: the Jurassic (195–150 Ma), when the magmatic activity was controlled by the northward high-angle subduction of the Neo-Tethys that produced volcanics of the Yeba and Bima formations; the Late Jurassic to Early Cretaceous (150–110 Ma), when the Neo-Tethys subducted at low-angles; the Late Cretaceous (110–80 Ma), when subduction was of the Andean-type and produced volcanic rocks of the Danshiting Formation; the Paleogene (70–40 Ma), when there was transition from ocean-to-continent subduction to continent–continent collision that produced volcanic rocks of the Linzizong Group.

L'Arbreda Cave is one of the southernmost of the Reclau Caves (Serinya, 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-Besald 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 delta O-18 and the sea-surface temperatures (SST) of the Alboran 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-2 the Last Glacial Maximum (LGM) in Levels C and B, the Bolling-Allered interstadial (B/A) in Level A, and the Preboreal/Boreal (Pr/B) in the Terra Rossa Level We want to thank the editor Dr. Paul Hesse and the three reviewers (Prof. Gloria Cuenca-Bescos and two anonymous) for their comments that improve the final version of the manuscript. This paper is part of the projects HAR2013-48784-C3-2-P, CGL2012-38358 and 2014-SGR900. Excavations ara funded by "Conselleria de Cultura Generalitat de Catalunya". J.M. Lopez-Garcia is a beneficiary of a Beatriu de Pinos postdoctoral fellowship (2011BP-A200001) from the Generalitat de Catalunya, a grant co-funded by the European Union through the Marie Curie Actions of the 7th Framework Program for R + D

In their comment, Oviatt et al. (this issue) criticize and dismiss our recent paper (Nishizawa et al., 2013) by arguing that it contains misinterpretations and unreliable radiocarbon ages, and therefore that our findings will confuse many people trying to understand the lacustrine chronology of the Bonneville basin. Their comment, however, does not present evidence to substantiate their criticisms against our paper. Oviatt et al. attribute statements to the paper that are not found in it, and their attempt to re-graph the radiocarbon ages omits 13% of our data. Numeric ages that Oviatt et al. contend are conflicting either are not or are not as problematic as those commenters claim. Comparisons of our lake-interval interpretations with sediment-core data likewise do not show the contradictions that Oviatt et al. claim. In essence, Oviatt et al. seem to advocate complete dismissal of all of our numeric ages and lake-size interpretations regarding MIS 3 on the basis of one tufa age. The following sections identify the incorrect information presented in the comment by Oviatt et al., review the complete set of numeric ages for the contested intervals, and respond to the implication that our late colleague, mentor, and coauthor, Donald R. Currey, did not actively participate in this research.

Martínez and Rojas (2013) published a paper about the relative sea level during the Holocene in Uruguay. The paper of Martínez and Rojas could be handled as an attempt to construct a sea-level curve from data collected from different sources: open-ocean coast, the Río de la Plata coastline and the outlet of Uruguay River. In this sense, several processes were involved: storm effects at open-ocean beaches, the Holocene enclosing of coastal lagoons, storms within the funnel-shaped estuary and the floods of the Uruguay River. However, they included a series of omissions, inaccuracies, errors and critics to our work, that need to be amended, rectified and argued. In response we present a historical background about the research on this issue in Uruguay. We refute the comments about the empirical framework used to construct the first sea-level curve for Uruguay (Bracco et al., 2008, 2011b). We point out that the assumptions on which the curve proposed by Martínez and Rojas (2013) is based are mistaken. In addition, there are limitations of the performed statistical techniques, and errors — mainly systematic — within their formulation. We present evidence that the decrease in sea level from middle Holocene would not have been constant. Instead, a rapid sea level decrease would have taken place by 4300 yr BP. Finally, we not only compare our sea level curve with that proposed by Martínez and Rojas, but also we corrected the altimetry errors incurred in their formulation. We conclude that the similarity supports the validity of our curve. Fil: Bracco, Roberto. Universidad de la República; Uruguay Fil: Inda, Hugo. Universidad de la República; Uruguay Fil: del Puerto, Laura. Universidad de la República; Uruguay Fil: Capdepont, Irina. Universidad de la República; Uruguay Fil: Panario, Daniel. Universidad de la República; Uruguay Fil: Castiñeira Latorre, Carola. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División Mineralogía y Petrología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Garcia Rodriguez, Felipe. Universidad de la República; Uruguay

Charcoal, predominantly the product of wildfires, is abundant in many sedimentary rocks deposited in a wide range of environments, from terrestrial to marine. It also occurs in some volcanic rocks. This paper outlines aspects of charcoal formation (both natural and experimental) and briefly considers the taphonomic processes leading to a final assemblage. This is done using examples from recent fires and through experimentation. The ways in which charcoal assemblages are recognized in the field and extraction in the laboratory are also considered. Methods of charcoal identification are presented. The range of charcoalified plant organs that can be found is discussed and a wide range of study methods outlined (including light microscopy, dark field light microscopy, reflectance microscopy, scanning electron microscopy and synchrotron radiation X-ray tomographic microscopy). Emphasis in this paper is on the study of macro- and meso-charcoal (above180 µm). Finally there is a consideration of the broad use of charcoal from plant evolution studies, fire history studies, vegetation studies, anatomical studies, climate and atmospheric studies and the wider importance of charcoal for the Earth and Biological Sciences. Charcoal is information rich but yet is an under-utilized resource.

In a recent paper (Heydari, E., Arzani, N., Hassanzadeh, J., 2008. Mantle plume: the invisible serial killer — application to the Permian–Triassic boundary mass extinction. Palaeogeography, Palaeoclimatology, Palaeoecology 264, 147–162) the cause of the end-Permian mass extinction was once again associated with the eruption of the Siberian Traps. However, this work considered the vast outpouring of flood basalts to be an incidental sideshow to the main event: the catastrophic release of huge volumes of methane to the atmosphere. This was attributed to a selection of sources – marine gas hydrates, thermogenic methane and methane from permafrost – that have been proposed by many authors previously. Uniquely, they suggest that the mantle plume (envisaged to have sourced the flood basalts) impinged beneath oceanic crust to the north of the Siberian flood basalts and that feeder dykes in the continental slope to the south heated sediments and released methane. There is no evidence for either of these two new proposed facets to end–Permian volcanism. The paper invokes an "oceanic acid bath" kill mechanism and dismisses claims for ocean anoxia at this time instead suggesting that end–Permian oceans were as well ventilated as those pertaining today. This latter claim simply ignores a vast body of sedimentological, palaeoecological and geochemical evidence for widespread anoxia in ocean and shelf settings at this time. The former claim for ocean acidity is equally suspect and based on the notion that a transition from calcite to aragonite-precipitating seas occurred at the Permian–Triassic boundary. However, previous studies have suggested that this interval occurs within a phase of "aragonite seas" and it is significant that most of the principal contributors to carbonate sediment in the Late Permian (calcareous algae and foraminifera) secreted aragonite.

Rousseau, D-D, 1990 Methods for the study of stratlgraphlcal records -- Introduction to Methods and Concepts m European Quaternary Stratigraphy " Palaeogeogr, Palaeochmatol, Palaeoecol, 80 I-6 The International conference "Methods and Concepts m European Quaternary Stratigraphy was held to take stock of the new developed concepts m Quaternary stratigraphy, to compare &fferent approaches and to evaluate the respectwe results m continental and marine environments The following papers, presented m this Issue, correspond to the theme "Methods for the study of stratlgraphlcal records ' They roughly indicate the average use of &fferent concepts developed m different dlsclphnes to Quaternary records Two biological objects are described m detad molluscs and pollen They are approached m two &fferent ways For the former, first of all by using a blogeographlcal approach based on the blome concept and secondly by trying to demonstrate the stratlgraphlcal value of mollusc assemblages m fluwal deposits For the latter, first of all by using a dynamxc approach to the vegetation cover of the middle mountain area of the Massif Central, France and secondly by using transfer functions to propose temperature and precipitation estimations from two long pollen sequences A last paper makes an evaluaUon of &fferent materml which can be ra&ocarbon dated and the rehablllty of the proposed dates, specmlly beyond 35,000 yr B P Ten years ago, European geologists who were dealing with Quaternary study met m Dijon to develop a common strategy concerning Quaternary stratigraphy (Chahne, 1980) The purpose was to homogenize and redefine a stratlgraphtcal approach accordmg to Hedberg's guide Three major recommendations were proposed (Paepe

In this paper, we provide a late Miocene (Tortonian) to early Pleistocene (Gelasian) palynological record from the Eryuan Basin, Yunnan Plateau, China, to investigate plant diversity over this time. Between 7.6 and 4.3 Ma, the palynological assemblage was dominated by coniferous trees (70.2% on average), with subordinate amounts of broadleaved trees (8.8% on average). This suggests that the vegetation mainly comprised mixed forests, and that the climate was relatively warm and humid. After 4.3 Ma, the proportion of conifer pollen increased overall, and amount of cold-temperate coniferous forest Picea and Abies pollen, in particular, increased significantly (from 19.1% to 41.9%), concurrent with decreases in the pollen of broadleaved trees, shrubs, herbs, and other plant taxa. We suggest that these plant variations and overall reduced diversity may be responses to the tectonic uplift of the Yunnan Plateau and global cooling.

The Nihewan Basin in North China contains the densest concentration of early Pleistocene Paleolithic sites outside Africa. This paper introduces a new archaeological site complex at Madigou (MDG) that was systematically excavated from 2011 to 2014 in the northeastern part of the Nihewan Basin. The site contains fossils and well-preserved stone artefacts in fluvio-lacustrine sediments. Our magnetostratigraphic results situate the MDG sedimentary sequence in the early Brunhes normal chron and the late Matuyama reverse chron, including the Jaramillo normal subchron. The MDG artifact layers are positioned within the pre-Jaramillo Matuyama chron, with an estimated age of ca. 1.2 Ma, close to the onset of Mid-Pleistocene climate transition. The MDG core and flake technology includes bipolar flaking of siliceous dolomite cobbles, and freehand flaking of chert and brecciated chert block fragments. Mammalian fauna and pollen compositions indicate that the MDG hominins lived in an open habitat varying from lightly-wooded grassland to an ecosystem dominated by sparse steppe near the shore of the Nihewan paleolake. Our combined results in the fields of archaeology, paleontology, palynology and magnetochronology suggest that innovations in technological behavior may correlate with adaptations to high environmental variability during the start of Mid-Pleistocene climate transition.

Neogene non-marine sedimentary rocks of the Bekaa Valley (Lebanon) are microfossil rich and show minimal lateral facies changes and post-depositional diagenetic alteration across continuous exposures. In this paper, we analyze the sedimentary facies and microfossils of three closely-spaced stratigraphic sections near the town of Zahle. The sedimentary sequence is divided, from base to top, into three intervals: (1) a massive conglomerate unit interpreted as alluvial fan deposits, (2) fossiliferous yellowish marls and limestone interpreted as perennial lacustrine deposits, and (3) an organic-rich marlstone intercalated with volcanic ash horizons interpreted as a palustrine interval representing an overall shallowing sequence. Intervals 2 and 3 contain a diverse microfossil assemblage comprising charophytes, terrestrial molluscs, a freshwater bivalve, ostracods as well as fish and mammal remains. The palaeoenvironmental characteristics and evolution of these lacustrine deposits are inferred through facies analysis and through comparison of microfossil tolerances with the ecological requirements of their nearest living relatives. Results suggest that during the Miocene the Bekaa Valley was occupied by a relatively shallow, stable, oligotrophic freshwater or slightly oligohaline lake that evolved to a very shallow eutrophic lake with a dense palustrine vegetation belt. The palaeolake ultimately regressed to the south due to climatic changes and tectonic stresses leaving the lacustrine deposits exposed in the area of Zahle as an erosional surface.

The Lhasa terrane is thought to be a key region for understanding the elevation history of the southern Tibetan Plateau after collision of continental India and Asia in early Paleocene. Stable isotopic studies consistently suggest that the Lhasa terrane had reached its near-present elevation before the Miocene. In this paper we report a plant megafossil assemblage from the Kailas Formation of the Kailas Basin in western part of the southern Lhasa terrane. Our U-Pb dating and magnetostratigraphic correlation show that the studied section of the Kailas Formation ranges from 25.1 Ma to 21.8 Ma in age, and that the fossil flora occurred at 23.3 Ma (latest Oligocene). The uppermost Oligocene Kailas fossil flora is low in diversity and dominated by Populus, Betulaceae and legume. It most likely represents a deciduous, broad-leaf vegetation and suggests a temperate, humid environment with a low to moderate palaeoelevation of 1500–2900 m in the Kailas Basin during the latest Oligocene, based on the co-existing range of the living analogues of the fossil plants. This conflicts with the existence of a continuous, high Gangdese Mountains stretching across the whole southern Lhasa terrane in the late Oligocene. Available evidence appears to suggest strong uplift of the southern Lhasa terrane after the latest Oligocene.

The separation of the Indian Plate from the Australia–Antarctic Plate and its accretion to the Eurasian Plate is the key to understanding the evolutionary history and paleogeographic reconstruction of Eastern Gondwana in the Jurassic–Cretaceous. In this paper, zircon U–Pb dating indicates that the Charong Dolerites (~ 142 Ma) are newly recognized Lower Cretaceous magmatic rocks in the central Tethyan Himalaya in southern Tibet. These dolerites are characterized by moderate contents of SiO2 (49.9–56.9 wt%), high contents of MgO (4.66–9.69 wt%) and TiO2 (2.20–2.81 wt%), high Zr/Y ratios (7.5–13.1), enrichments in Rb and Th, moderately negative Nb–Ta anomalies, and no Zr–Hf anomalies. Taking into account the narrow range of whole-rock initial 87Sr/88Sr ratios (0.7068 to 0.7086), the negative values of eNd(t) (− 2.4 to − 4.1), and the geochemical makeup of the zircons, the Charong Dolerites are akin to continental basalts, indicating that the central Tethyan Himalayan area was in an extensional setting during the Early Cretaceous. Although the Charong Dolerites indicate a relatively high mantle-melting temperature (~ 1469 ± 44 °C), this is still lower than the temperature required for a mantle plume origin. In combination with the Lower Cretaceous mafic rocks in the eastern Himalaya and the coeval volcaniclastic sediments, we suggest that the Charong Dolerites were partial melts of a rising asthenospheric mantle, this process having been triggered by rifting between the Indian Plate and the Australia–Antarctic Plate. This episode of continental lithospheric extension may have led to the opening of a post-Neotethyan oceanic basin that extended between the Indian Craton and the Tethyan Himalaya during the late Early Cretaceous, a feature that is highly significant in paleogeographic reconstructions of Eastern Gondwana.

In this paper, we build an age model by tuning the G. ruber δ18O curve to the LR04 stack and U1308 benthic δ18O curve with the aid of the high-resolution lightness parameter L*, which mirrors the marine oxygen isotope stages, and we analyse the major palaeoenvironmental events indicated by different proxies, particularly the >250 μm fraction and the 150–250 μm fraction of ice-rafted debris (IRD) at IODP Site U1312. In general, the input of IRD at Site U1312 can be divided into two stages. In Stage 1, ranging from ~2.6 Ma to ~1 Ma, the number of lithic grains was small, the frequency of ice rafting events was low, and the components were diverse and mainly comprised quartz, feldspar and clasts. In Stage 2, ranging from ~1 Ma to the present, the number and frequency of lithic grains considerably increased and were accompanied by detrital carbonate additions derived from the Hudson Strait after ~650 ka. Regarding the IRD features in the study area, the distinctive layers are as follows. IRD did not occur until 2.52 Ma at Site U1312, implying that icebergs discharged by the Northern Hemisphere glaciers bearing lithic grains were involved in pelagic sedimentation for the first time. Interestingly, a monotonic component of debris, magnetite with some ilmenite and quartz, was observed in a single layer at approximately 1.4 Ma. The source of this component may simply be the erosion of volcanic formations in Iceland during the glacial period. Detrital carbonate played an important role in the IRD component after ~650 ka, and the input and frequency of IRD increased dramatically, revealing glacier enhancements and the instability of the Laurentide ice sheet. The IRD characteristics at Site U1312 during MIS 22, MIS 12 and MIS 6 were different from those at other sites near the IRD belt and may be closely related to the European ice sheets. During MIS 10-8, the input of IRD was high, the dominant warm species G. ruber was too rare for the isotope test to be conducted, and the abundance of planktonic foraminifera severely declined, which may indicate that extreme conditions occurred at Site U1312 during this interval.

The 4.2 ka Event has generally been regarded as a period of decades to at most a few centuries in which comparatively dry conditions existed in the Middle East and more broadly across the mid-latitude Northern Hemisphere. This paper presents new stable-isotopic and petrographic observations from two previously-unreported U-Th-dated stalagmites from Dante Cave in northeastern Namibia. The results are most compatible with wetter conditions during the 4.2 ka Event, and wetness during the 4.2 ka Event is the only inference supported by evidence. These new results add to observations previously reported from a third Dante Cave stalagmite suggesting a comparatively wet 4.2 ka Event in which Africa's Tropical Rain Belt migrated southward and rainfall increased along the Congo Air Boundary and/or Kalahari Discontinuity. The new results support findings from three other locations in Namibia and Botswana, from at least seven other locations in the Southern Hemisphere, and at least one in southern China, that suggest a wetter rather than drier 4.2 ka Event in those regions. The pattern emerging from these sites generally agrees with recent modeling results indicating increased moisture over broad areas (but not all) of the Southern Hemisphere. This in turn suggests a 4.2 ka Event that was not a global drought but was instead a set of latitudinally-dependent responses to global-scale southward migration of the Inter-Tropical Convergence Zone (ITCZ), and thus Africa's loosely linked Tropical Rain Belt, as a result of cooling of the Northern Hemisphere, which brought drier conditions to some areas and wetter conditions to others.

Disentangling fire and its controls over thousands of years ago is a major challenge in the study of paleofires. In this paper, we synthesize sedimentary charcoal and black carbon from the coastal plain of Laizhou Bay, China to improve our ability to reconstruct fire history in the past 5000 years, and to assess the controls of fire using principal component analysis and multiple regression approach. The results show that there were three distinct fire episodes at the intervals of 5300–5100 yr BP., 1190–1060 yr BP., and 300–0 yr BP., based on the Changyi (CY) profile. A large-scale fire episode was synchronous with a rapid climate variability that occurred 5300 yr BP., which had frequent drought and cold epoch. High fluxes of black carbon and charcoal were closely related to mass migration and the use of fire for land reclamation from 1190 to 1060 yr BP. Subsequently, anthropogenic biomass burning for cereal cultivation has reached a higher level over the past 300 years. However, between 4600 and 4000 yr BP. the shifts in the frequency of high-magnitude floods and climate aridity consequently resulted in the decline of fire-episode frequency and the abandonment of the late Neolithic settlements in the study region. Therefore, climate is still a prerequisite factor for fire occurrence on the southern coast of Laizhou Bay in the past 5000 years. A rapid climate variability was not only responsible for various fire patterns, but also could affect human settlements and the mode of production during middle-late Holocene. In the past 1000 years, human land use has been a more important control of fire. However, temperature has become one of the evidently identified controls of fire across the study area in recent decades. To synthesize the methods of Principal Component Analysis and Multiple Regression Analysis with multi-proxy evidence is necessary for us to better understand fire and its controls on coastal plain of Laizhou Bay at the region.

The Upper Pleistocene (MIS5) site known as Cova del Rinoceront near Barcelona, Spain, contains a large assemblage of ungulate remains, among which the most dominant, in the uppermost Layer I, are those of the rare Mediterranean deer, Haploidoceros mediterraneus. In this paper, zooarchaeological and coprogenic analyses are used to evaluate the taphonomic and geological processes involved in determining the nature of the Layer I assemblage. The assemblage cannot have been generated by either hyenids or humans, nor does it constitute an accidental collection, as seen in other Pleistocene accummulations. Instead, the skeletal frequencies, coprogenic tracemarkers and the diagnostic biological damage on bones suggest it accumulated as a result of the feeding of a carnivore. The homogeneous pattern of carcass utilization and the predation of similar-sized ungulates suggest a canid as the main biological agent.

Once perceived as a continent-wide extinction event, doubts have been raised as to the severity and extent of the Vallesian Crisis. In this paper, we use the high-resolution late Aragonian to middle Turolian micromammal record from both the coastal Valles-Penedes Basin and inland Calatayud-Teruel Complex to determine geographic extent of this late Miocene turnover event and its effects within the reaches of the Iberian Peninsula. Differences in faunal composition between the two regions confirm that the event was much less severe than previously thought. Surprisingly, the diversity peaks in the two regions do not coincide. Whereas at the coast highest diversity is found in the early Vallesian (just before the turnover), in the inland it peaks in the late Vallesian. Several taxa never made it inland as reflected by the low similarity between both regions during the early Vallesian, suggesting that the Valles-Penedes was indeed unique and consistently showed higher affinities with northern regions. The large differences even at relatively short distances support the idea that the ‘Vallesian Crisis’ was a local event.

I analyzed phytoliths from soil profiles on San Cristobal Island in the Galapagos Islands to determine whether historical human impact and recent vegetation dynamics are visible in the phytolith record. I extracted phytoliths from soil samples taken from four test pits located at the village, an abandoned field, a forest, and an active agricultural field - all located within the former El Progreso plantation (AD 1860–1920). Changes in the ratio of tree to grass phytoliths with depth in all four samples suggest changes in vegetation composition from forest to open vegetation dominated by grasses, which reflects the removal of forest with colonization and the first permanent human occupation of the archipelago in the middle 19th century. This paper shows that the changes in vegetation brought about by colonization and land clearing for plantations are documented in the soil phytoliths record, and suggests that phytoliths can be used as an indicator of past vegetation change in future work on the historical ecology of the Galapagos archipelago.

Many mangrove wetland systems in deltaic environments are negatively affected by massive sedimentation from river inflows. In this paper we use the example of the Save River delta to assess the palaeogeographic distribution of mangrove wetlands and to analyze their dynamics. To track past occurrences of mangrove wetlands in the study area we have integrated sedimentological data with siliceous microfossil analysis combined with AMS radiocarbon and OSL dating. The results show a fine-grained deposit with an approximate thickness of 2 m, present at different sampling sites. In the upper deltaic plain, the deposit is interbedded between sand layers, while in the lower deltaic plain the deposit occupies the uppermost stratigraphic position. In most of the sampling sites the deposit shows a succession with brackish-marine diatoms at the bottom of the sequence while the upper part shows only scattered occurrences. Based on sedimentological and microfossil characteristics we have interpreted the layer to represent a mangrove wetland deposit. The development of the deposit in the study area is suggested to have been initiated around 3100 cal. yr BP, induced by sea-level rise. Thereafter, the development followed the combined effect of a sea-level fall and delta progradation processes. In some areas, particularly in the proximal part of the delta, the mangrove deposit has developed progressively on top of the delta-front. From around 1300 years ago (OSL) onwards, massive alluvial sedimentation impacted the mangrove ecosystem. However, the retreat of mangrove wetland coincided with a regional fall of sea level. At the edges of the alluvial deposit, the current mangrove ecosystem has reclaimed the habitat in some sectors where gully erosion has exposed the once extinct mangrove habitat.

Pollen analysis provides a key technique for the reconstruction of post-glacial vegetation. Modern observation of the plant-pollen relationship, through the use of surface pollen studies, is an instrumental process for informing these reconstructions. However, results from surface pollen studies suggest that the diversity of pollen assemblages is rarely a faithful representation of the diversity of the local vegetation. Pollen diversity at high altitude is determined by both the composition and density of the local vegetation and long-distance pollen. This paper examines the relationship between floristic and palynological diversity using surface samples collected from alpine communities found on three glacier forelands (Austerdalsbreen, Storbreen and Grjotbreen) in the Jostedalsbreen-Jotunheimen region of Norway. Several diversity indices indicate the complexity of the relationship between palynological and floristic diversity. This is accentuated in open, high altitude, sparsely-vegetated sites, where palynological diversity is a measure of the diversity of the long-distance pollen assemblage rather than the diversity of the local vegetation. Even at sites on older moraines at Storbreen and Austerdalsbreen, where the vegetation is denser and more diverse, the relationship is not simple but depends on pollen production of the taxa that dominate the local vegetation. On Storbreen foreland, for example, the diversity of small, insect-pollinated plants growing locally is poorly represented in the pollen assemblage which is dominated by long-distance arboreal pollen. The surface pollen results were compared with fossil pollen data from a palaeosol at Memurubreen in Eastern Jotunheimen. DCA ordination indicates that the fossil pollen spectra are distinct from the modern samples, due to differences in the pollen assemblages, probably related to lower treelines in the past associated with climatic cooling or human impact. The palaeosol samples are most similar to modern samples from heath and snowbed communities, found on older terrain at Grjotbreen and Storbreen, and the diversity indices also show strong similarities with these communities. The potential for improvements in methodology to increase resolution is considered.

Trace fossils are especially useful to elucidating metazoan evolution and species extinction events through geologic history. This paper reports results of an investigation of well exposed microbialites in the Cambrian Series 2 (upper Toyonian–lower Amgan) Qingxudong Formation (QF) of the Panshi area, eastern Guizhou Province. Light and scanning electron microscopic examination of these deposits has revealed for the first time small Planolites. Detailed analysis of these trace fossils has helped elucidate their mode of formation mechanism and their relationship with the extinction of Archaeocyathids early in the Toyonian. Our results suggest that the trace-makers had a trophic specialization strategy and selectively fed in a low-energy and Girvanella-rich environment. They were the pioneers of ecosystem recovery following extinction of reef-building Archaeocyathids and had survived the earlier oxygen-depleted environment. Sedimentary facies evolution manifested by the studied deposits and penecontemporaneous siderite indicates that the trace fossils formed in a shallow sea in which a weakly reducing, sulfur-poor sedimentary environment had been established in association with transgression. The recovery and expansion of microbial reefs and the miniaturization of trace fossils suggest that the anoxic environment severely inhibited metazoans and may have contributed significantly to the extinction of reef-building Archaeocyathids during the early Toyonian time and the slow recovery of ecosystems that followed. Our results provide impetus for further research on the extinction event and the recovery process of metazoans in the late period of Cambrian Epoch 2.

Proximal alluvial sediments represent a useful sedimentary archive to reconstruct the tectono-climatic history of continental rift basins. However, poor dating of coarse fluvial successions usually prevents high-resolution distinction of tectonic and climatic processes, and thus good determination of process rates. This paper presents a dating study of Plio-Pleistocene Kalavryta river system during the early history of the Corinth Rift (northern Peloponnese, Greece) based on magnetostratigraphy and palynology. This river system developed across several active normal fault blocks that are now uplifted along the southern rift margin. The detailed sedimentary record constrains alluvial architectures from the proximal basin to the river outlet where small deltas built into a shallow lake. In four magnetostratigraphy sections the correlation to the reference scale relies on the identification of the Gauss/Matuyama magnetic reversal and biostratigraphic elements. The river system developed between about 3.6 to 1.8 Ma, with sediment accumulation rates (SARs) ranging from 0.40 to 0.75 mm yr−1. SAR is lower in the alluvial fans than in the deltaic system, and higher at the centre of the normal fault depocentres than at the fault tip. By comparison with worldwide Cenozoic SARs, our values are higher but lie in the same range as those determined in coarse alluvial foreland basins. Moreover, in the context of overfilled intra-mountainous rift basins, these rates are minimum values and can be used as a proxy for accommodation rate. Therefore, early rift stratal wedges and growth synclines attest high sedimentation rates and also high rates of tectonic processes. Finally, in the distal river system, floral compositions and changes of vegetation deduced from palynological data are coherent with alternating fluvio-deltaic and shallow lacustrine deposits, which are linked to relative base level variations. Dry/cool climate is preferentially recorded during periods of low lake level, while the warm/moist climate is mainly recorded in prodelta deposits during periods of high lake level. This correlation suggests that, despite the dominant control of active faulting, climate is a key control of syn-rift stratigraphic architectures.

Resolving the history of vegetation, fire, and glaciation on the eastern slope of the central Patagonian Andes (44°-49°S) since the Last Glacial Termination (T1) has proved difficult. This is due to the steep environmental gradients, vegetation heterogeneity, and scarcity of dated glacial deposits and geomorphic features. Unsurprisingly, published records show important heterogeneities which limit our understanding of the timing and magnitude of climate and vegetation changes, and their driving mechanisms since T1. In this paper, we describe sediment cores from small closed-basin lakes located in the deciduous Nothofagus forest zone near Coyhaique, Chile. Our results indicate that the Coyhaique glacier lobe abandoned its final Last Glacial Maximum position just before ~17.9 cal kyr BP and underwent a step-wise recession that included a halt/readvance that culminated at ~16.8 cal kyr BP, contemporaneous with the formation of an ice-dammed proglacial lake in the Coyhaique/Balmaceda sector. This glacial lake stood at its highest level between ~17.9–17.2 cal kyr BP ( 650 m.a.s.l.), lowered between ~17.2–16.2 cal kyr BP ( 570 m.a.s.l.), and disappeared thereafter. Herbs and shrubs, currently dominant in high Andean and Patagonian steppe environments, colonized the ice-free terrains distal to the glacier margins and proglacial lakes under cold and dry conditions. This was followed by a steady increase in Nothofagus between ~16.6–14.8 cal kyr BP that led to the establishment of forests starting at ~14.8 cal kyr BP. The Holocene started with a sudden increase in Nothofagus and disappearance of conifers in the context of increase fire activity between ~11.7–9.4 cal kyr BP. Closed-canopy Nothofagus forests persisted virtually unaltered from ~9.4 cal kyr BP to the present day, despite frequent explosive volcanism and millennial-scale variations in fire regimes, attesting to their extraordinary postglacial resilience which contrasts with their behavior during T1. Recent large-scale deforestation by fire, livestock grazing, and the spread of non-native invasive plant species drove the fastest and largest-magnitude shifts seen during the last ~16,500 years.

Fish bones are common in Pleistocene cave deposits in Europe. In this paper, we report on fish remains from the Gran Dolina cave (Trinchera del Ferrocarril) in the Sierra de Atapuerca in Spain, to increase what is known of the freshwater ecosystems close to the cave. The 19-m-thick section, divided into 11 stratigraphic levels, represents an Early to Middle Pleistocene time span as dated by biostratigraphy, ESR, U-series, and magnetostratigraphy. We focus on the Sondeo South site, excavated from 1993 to 1999, which has yielded 1087 fish bones comprising the following taxa: brown trout (Salmo trutta), the common European eel (Anguilla anguilla) and chub (Squalius sp.). Taphonomic studies suggest that the European eagle owl (Bubo bubo) was the most likely predator responsible for the accumulation. Changes observed in the body size of brown trout through the sequence cannot be attributed to climate change (contravening Bergmann's rule). Our study documents the presence of a pre-mountain river system characterized by permanent, oxygen-rich, relatively cold flowing waters around the Sierra de Atapuerca during Early-Middle Pleistocene times.

Improved studies of past vegetation change are required to better understand the variation of alpine ecosystems on the Qinghai-Tibetan Plateau (QTP) in response to future climate change. Spatial and temporal variations of past vegetation can be traced by fossil pollen data mapping. In this paper, we synthesized 57 continuous pollen records on the QTP covering the past 15 kyr to depict large-scale vegetation change and its response to climate variations. In order to minimize potential chronological biases, age-depth models were revised using a state-of-the-art and consistent method for all the records. The spatial and temporal variation of major pollen taxa were examined based on interpolated pollen maps at 1000-year intervals. The arboreal pollen (AP, mainly of Pinus, Betula and Abies/Picea) content expressed significant climate signals over a broad spatial and temporal gradient. During the late glacial period, high proportions of AP widely occurred in regions that are presently unforested owing to the sparse local vegetation coverage. For the Holocene period, AP showed relatively high contributions in records from the southeastern margin of the QTP, with a decreasing gradient in abundance towards the northwest. The transportation of AP to unforested regions corresponds closely to the intensity of monsoon wind, which can be used to track the Holocene evolution of the summer monsoon. The dominant shrub and herbaceous taxa (including Artemisia, Chenopodiaceae, Cyperaceae, Poaceae and Ephedra) generally represent developments of local vegetation responding to climate variations. In addition, the persistent increase in Poaceae pollen during the mid to late Holocene correlates possibly to regional human activities. The inferred spatial and temporal patterns of major pollen types on the QTP provide significant knowledge about long-term vegetation change and its potential response to climate variations.

International audience; Understanding the formation of the Qilian Shan in the NE Tibetan Plateau provides insights into the growth mechanisms of the northern portion of the plateau through time. The onset time of exhumation in the Qilian Shan is still debated. The Qinghai Nan Shan subrange, located in the southeastern Qilian Shan, is cut by the Yellow River that forms Longyang Gorge, providing a good vertical profile for thermochronological investigation of exhumation. In this paper, we reconstruct the cooling and exhumation history of the Eastern Qinghai Nan Shan using apatite fission-track(AFT) and apatite (Usingle bondTh)/He(AHe) thermochronological dating on basement rocks. The fission-track data display a marked age-elevation trend from Early Cretaceous (114–122 Ma) ages at the bottom of the canyon to Early-Middle Jurassic ages (165–180 Ma) at the top. Mean (Usingle bondTh)/He ages are mainly Early Cretaceous (97–128 Ma) with one Eocene outlier (42 Ma). Combined with fission track lengths, Dpar values and thermal modeling results, these data indicate that the study area resided above the closure temperature of AFT and AHe until Early Cretaceous. Rapid cooling occurred during the Early Cretaceous and early Cenozoic likely driven by the Lhasa and Indian blocks collision with the southern margin of the Asian continent. Nonetheless, since then exhumation was limited to less than a few kilometers in the study area. Combined with regional geological studies, the thermochronological analysis demonstrates that, since the Mesozoic, intense exhumation occurred simultaneously along the northern and southern margins of the Qilian Shan. Hence, we suggest that the geomorphic framework of the northeast margin of the Tibetan Plateau was established during the Early Cretaceous-early Cenozoic.

Raman spectroscopic analyses of thermally altered organic materials can be used to assess the paleothermometry of the sedimentary deposits. Although this technique has been widely applied to diverse microfossils, macroscopic vertebrate fossils have been neglected. In this paper, we show that fossil eggshells can be used for this purpose by demonstrating the paleothermometric potential of diverse amniotic eggshells from the Wido Volcanics (Upper Cretaceous, South Korea) that contain thermally altered organic material. We estimate the maximum paleotemperature recorded in the eggshells using Raman spectroscopic data and the spectrum deconvolution technique, which was invented and developed by organic geochemists. The results show that the same type of eggshells record different paleotemperature gradients depending on their spatial distribution in the fossil locality, whereas different types of eggshells from similar locations show similar paleotemperature gradients (except for one specimen with a peculiar microstructure). These findings are further supported by Fourier transform infrared spectroscopic results, which focus on thermally altered organic materials, and electron backscatter diffraction data, which focus on calcite twinning. This study suggests that fossil eggshells are useful and reliable materials for paleothermometry because thermally altered organic materials and calcites of eggshells provide independent opportunities to assess paleothermometry. We propose that fossil eggshells may be useful for evaluating the thermal evolution of sedimentary basins.

In this paper, we review evidence for a major biotic turnover across the Oligocene/Miocene in the Tibetan Plateau region. Based on the recent study of six well-preserved fossil sites from the Cenozoic Lunpola and Nima basins in the central Tibetan Plateau, we report a regional changeover from tropical/subtropical ecosystems in the Late Oligocene ecosystem (26–24 Ma) to a cooler, alpine biota of the Early Miocene (23–18 Ma). The Late Oligocene fossil biota, comprising of fish (climbing perch), insects and plants (palms), shows that the hinterland of the Tibetan Plateau was a warm lowland influenced by tropical humidity from the Indian Ocean. In the Early Miocene, the regional biota became transformed, with the evolution and diversification of the endemic primitive snow carp. Early Miocene vegetation was dominated by temperate broad-leaved forest with abundant conifers and herbs under a cool climate, and mammals included the hornless rhinoceros, Plesiaceratherium, a warm temperate taxon. This dramatic ecosystem change is due to a cooling linked to the uplift of Tibetan region, from a Late Oligocene paleo-elevation of no greater than 2300 m a.s.l. in the sedimentary basin to a paleo-elevation of about 3000 m a.s.l. Another factor was the Cenozoic global climatic deterioration toward to an ice-house world.

Major reorganizations in climate and tectonic regime occurred in East Asia during the Pleistocene, resulting in large-scale environmental changes. In this paper a detailed geochemical and mineralogical record of these changes is presented from a distal alluvial fan sedimentary sequence in the northern Weihe Basin. We established that, in addition to glacial-interglacial variation, there are three distinctly different units deposited over the past 1 m.y. These units are the result of variations in the overall tectonic regime in the northern Weihe Basin. Fine-grained detrital minerals were predominantly delivered during colder climatic periods, whereas evaporative minerals were dominantly deposited during the warmer, interglacial periods, probably as a result of strong seasonal contrast. This compositional variation demonstrates the importance of climate control on hinterland erosion, surface runoff, chemical weathering and evaporation. Al-normalized ratios of indicative major elements relative to average loess composition, indicate important variations in sedimentary processes, mostly related to sediment flux. Si-enrichment is an index for past flooding events, while Fe enrichment, just like K and Ti, reflects influx of clays. In contrast, Ca and Mn are strongly enriched throughout the core, associated with the authigenic precipitation of carbonates, especially during interglacial periods. The lower (~ 1000–690 ka) and upper (~ 330–0 ka) units of the core are characterized by relative intense and frequent flooding, which coincided with extensive ponding in the study area. In the middle unit (~ 690–330 ka) increased salinity levels caused by evaporation, as reflected in the high Sr/Ca ratio and dolomite abundance, led to increased carbonate precipitation. Simultaneously, the increased influx of fine sediments indicates increased clay production in the source area as a result of a more intense summer monsoon strength after 600 ka. © 2017 Elsevier B.V.

Artemisia and Chenopodiaceae are the two main pollen taxa in studies of lake sediments on the central and western Tibetan Plateau (TP). In this paper, we present Artemisia /Chenopodiaceae (A/C) ratios in pollen assemblages of surface sediments from 42 lakes on the central and western TP. Relationships between vegetation, climate and A/C ratio are investigated. The results show that the A/C ratio in the study region can distinguish desert from steppe vegetation. As a whole, the A/C ratio was higher than 1.2 in the steppe vegetation and lower than 1.2 in the desert vegetation zone. Statistical analysis revealed that the A/C ratio can be used as a moisture indicator on the TP. Based on the A/C ratio in pollen assemblages of sediment core TAN12-2 from Lake Tangra Yumco, we reconstructed the vegetation and climate history of the southern TP during the transitional period from the late glacial to the Holocene (17.5–10 cal kyr BP). From 17.5 to 16 cal kyr BP, desert vegetation occurred and climate was extremely dry. During 16–15 cal kyr BP, desert was replaced by steppe vegetation and climate became wetter. From 15 to 10 cal kyr BP, the lake basin of Tangra Yumco was covered by the steppe vegetation and climate tended to be more humid. Comparing our results with other lacustrine records on the TP, we found that the Indian summer monsoon (ISM) significantly affected the southern TP earlier than the northeastern TP.

Analyses of stratigraphic sequences within the paleocanyons of the Hualapai Plateau, Arizona, are important because these deposits offer the only evidence for the Paleogene-Neogene geological history of the Grand Canyon area. In this paper, we focus on the origins and paleoenvironmental significance of the West Water Formation, located within the Milkweed and West Water paleocanyons on the Hualapai Plateau. We propose that the supposed “limestone unit” of the West Water Formation at and near its type section is not a limestone; rather, it is a 21 m-thick valley calcrete, overprinted by a ~ 1–2 m-thick pedogenic calcrete, and subsequently dolomitized in its upper-to-middle sections, with a superimposed 4 m-thick red paleosol. We also propose that this unit is not coeval in age or origin with the Long Point limestone on the Coconino Plateau, and that the presence of a complex calcrete-dolocrete-paleosol alters previous interpretations associated with this unit. Evidence for a calcrete-paleosol origin, beyond the West Water Formation's lack of fossils, includes: its predominantly micritic calcite-palygorskite composition; its textures characteristic of valley and pedogenic calcrete deposits (as exhibited by thin section, SEM, and TEM analyses); and its association with a relatively thick overlying red paleosol that also contains abundant palygorskite. Stable carbon and oxygen isotope values from carbonate cements are also within the range expected of a near-surface calcrete. Carbonate minerals within the calcrete-dolocrete were precipitated at or near the water table in a valley setting due to evaporation and/or CO 2 degassing in a semi-arid to arid environment of deposition. High 87 Sr/ 86 Sr values within the calcrete were inherited from groundwater infiltrating through Music Mountain Formation arkosic sediments, which were derived from a Precambrian source terrane to the south and southwest. No absolute ages exist for the Music Mountain Formation and West Water Formation in the Milkweed and West Water paleocanyons; these sediments could range in age from the Late Cretaceous to the latest Eocene-earliest Oligocene, and may record the Eocene-Oligocene Transition in the Grand Canyon area.

This paper provides a high-resolution temperature reconstruction for the last Millennium from Lake Atnsjøen, SE Norway (61°52′31″N, 10°10′37″E). The sedimentary record reveals strong influence of the large-scale global climate patterns on the local climate in southern part of Eastern Norway. We reconstructed mean July air temperature using Chironomidae-based transfer function and fossil Chironomidae assemblages. The reconstruction was supported by a selection of climate-sensitive geochemical and paleoecological sedimentary proxies of terrestrial and aquatic origin, including Cladocera, pollen and macrofossils. Presented results revealed that summer temperatures were 1–2 °C warmer than the mean Millennial temperatures during the 11th, 13th, 15th and 20th centuries and 1–2 °C lower during the 12th, 14th, 17th–18th centuries. A persistent cold period, the Little Ice Age (LIA), occurred between 1550 and 1800 CE, was interrupted by a short warming at 1650 CE. The recognized regional climate fluctuations during the last Millennium affected the lake and its catchment, of which the strongest impact was caused by the LIA cooling. During the LIA the catchment vegetation was impacted by climate deterioration and the lake productivity reached its lowest level during the last Millennium. The current temperature reconstruction is in agreement with a previous continental scale temperature reconstruction for Europe. From obtained results it emerges that during the LIA the climate of western Scandinavia has been dictated by the atmospheric patterns originating from the North Atlantic. peerReviewed

This paper describes the results of a multidisciplinary study of four geoarchaeological sites on the Sorrento Peninsula coast (Italy) where the submerged ruins of Roman buildings have enabled the ancient position of both the sea level and the coastline to be reconstructed. The results highlight that the sea level in Roman times, deduced from the submersion measurement of archaeological markers, did not exceed 1.2 m ± 0.30 m, except for Seiano whose submerged remains and surrounding area were heavily damaged by extreme events following the 79 CE Vesuvius eruption. The comparison of these results with the eustatic sea-level curve in Roman times together with the submersion of the tectonically stable site on the Tyrrhenian coast of Italy (Torre Astura, with a well-preserved Roman fishpond) demonstrate that the Sorrento Peninsula has been tectonically stable over the last two millennia. This behaviour started many thousands of years ago, not later than the last interglacial, while the nearby plain of Pompeii and probably the bottom of the adjacent Gulf of Naples have been subsiding at rates of 1 or more mm per year. In the same time span, two of the investigated coastal sectors (Capo di Sorrento and Punta Campanella) have not suffered any significant changes because their sea cliffs are cut in hard limestone. The tufa sea cliff of the Sorrento plain on the other hand, has been retreating by several metres. On the Marina di Equa (Seiano) alluvial coastal plain, which suffered the effects of the 79 CE eruption, the debris and hyperconcentrated flow produced a progradation of > 200 m, which has been totally dismantled over three centuries.

Millennial-scale variations in the Asian monsoon vapor transport are always associated with long-term changes in monsoon rainfall according to the conventional understanding. However, recent advances in monsoon studies suggested that regional monsoon rainfall has different responses to monsoon vapor transport. This paper presents a comparison between monsoonal vapor and precipitation records along the path of the Asian summer monsoon vapor transport. Pedogenic carbonate δ 18 O values in both surface sediment and Holocene eolian and lacustrine sediments from the Shiyang River drainage basin were used to investigate the variations of the Asian monsoon vapor transport. Meanwhile, Holocene lake-level changes of the terminal lake were reconstructed to reflect the monsoon precipitation variability. The results show that millennial-scale monsoon vapor transport is in accordance with low-latitude summer insolation, while the increasing summer monsoon rainfall during the early Holocene lags the monsoon water vapor transport. In addition, the relatively cold oceans left over from glacial periods and slow melting of ice sheets may temper the onset of the rainfall. These findings can provide insights into the interpretation of the asynchronous Holocene records from lakes and caves in East Asia.

Evaluating and understanding bio-environmental relationships at different spatial and temporal scales is important for accurately assessing marine productivity in relation to oceanographic conditions in changing Arctic ecosystems. In this paper, we compare four different bio-environmental datasets, in order to shed new light on the complex marine ecosystem of the Baffin Bay-Labrador Sea region, as well as the historical links between environmental changes and the ecosystem. Satellite dataset was used to describe the regional distribution of chlorophyll a, sea ice concentration (SIC), sea surface temperature (SST) and sea surface salinity (SSS). Chlorophyll a data were also analysed together with shrimp assessment dataset to examine the relationship between marine pelagic productivity and bottom feeders off the Greenland coast. A microfossil dataset (diatom valves) from 57 surface sediment stations was used to describe diatom concentration and diversity across the study region. It was also used in combination with satellite data from the same sites to analyse species-environment relationships and develop a diatom-based transfer function for reconstructing past changes in SIC, SST and SSS. Subsequently, we applied the diatom transfer function on three short sediment cores from off SW and W Greenland spanning the last few centuries. A monitoring dataset of sea ice observations and instrumental measurements of water temperature and salinity, together with atmospheric data (air temperature and wind conditions) from Greenland, were used to develop a more complete picture of 20th and 21st century changes in ocean-climate conditions. Our comparative analyses show clear spatial distribution patterns of marine phytoplankton and identify key ecological groups linked to oceanic conditions. In addition, we find a significant correlation between the different trophic levels, culminating in a ‘productivity boom’ in 2001 CE. On a longer temporal scale, the transfer function reconstructions reveal a good correlation with the satellite, monitoring and observational trends, as well as a consistent, long-term decrease in sea ice linked to ocean-climate variability.

This paper analyzes the distribution patterns of pollen and spore assemblages in modern surface sediments recovered from the bottom of the San Jorge Gulf (SJG) and from offshore sites, in relation to the location of different phytogeographic provinces surrounding the SJG, including the distant forest from southwestern Patagonia. Results reveal that pollen spectra are dominated by Chenopodiaceae-Amaranthaceae, Poaceae, Asteraceae subf. Asteroideae, Colliguaja integerrima and Ephedra sp.; which represents the vegetation adjacent to the SJG. Overall, the pollen distribution in surface sediments reflects the location of the different phytogeographic provinces and will be used as modern-analogues to document vegetation history around the SJG. Pollen assemblages also reveal the latitudinal variation of vegetation taxa in the Patagonian steppe, which is characterized by a slight increase in herbaceous pollen and a decrease in high shrubs (e.g. Colliguaja integerrima) towards the southern-central part of the SJG. Furthermore, we identified two pollen taxa from the southwestern Patagonian forest, Nothofagus and Podocarpus that could be used as indicators of past dynamics and variations of the Southern Westerly Wind Belt (SWWB) in the SJG during the Late Pleistocene and Holocene. High pollen concentrations are recorded at the central part of the SJG (480–8080 grains/g), while low concentrations are measured in the northern and southern parts of the Gulf, as well as at offshore sites (26–1806 grains/g). The pollen distribution in the study area is most likely governed by the SWWB in combination with the marine sediment composition and surface currents flowing through the SJG. Fil: Faye, Simon. Université Du Québec Á Rimouski; Canadá Fil: Rochon, André. Université Du Québec Á Rimouski; Canadá Fil: St Onge, Guillaume. Université Du Québec Á Rimouski; Canadá Fil: Vilanova, Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina

Terrestrial deposits of the Triassic-Jurassic transition are well developed in the Junggar Basin, located in the Haojiagou Valley of Urumqi, Xinjiang Uygur Autonomous Region of Northwest China. This paper describes the palynology of a 10 m thick lignite bed from the Upper Triassic Haojiagou Formation (Rhaetian) with the aim of reconstructing the palaeovegetation and palaeoenvironment of a peat-forming wetland near the Triassic-Jurassic boundary. The palynoflora contains both Eurasian and Gondwanan elements, and is dominated by the spores and pollen of Bennettitales, Corystospermales, Ginkgoales, and Gleicheniales. At the Triassic/Jurassic boundary (Hettangian), the palynoflora significantly changes as Cyatheales spores become the dominant elements. We analyze assemblages in terms of an Eco-Plant model, which assigns the parent plants of the palynomorphs into five groups based on humidity and four groups based on temperature, and uses multivariate statistical analyses to infer palaeoclimate and palaeoenvironmental conditions. Results suggest that the palaeoclimate of the Rhaetian was generally wet and subtropical with short seasonal drought periods. Our analysis shows that an Eco-Plant model may be a useful tool to reveal past vegetation patterns and climate changes, applicable to other Mesozoic assemblages.

This paper is not subject to U.S. copyright. The definitive version was published in Palaeogeography, Palaeoclimatology, Palaeoecology 451 (2016): 73-83, doi:10.1016/j.palaeo.2016.03.018.

In the Early Jurassic, the epicontinental Central European Basin (CEB), including the North German Basin (NGB), was covered with a semi-enclosed inland sea that was in the late Middle Jurassic transferred to a continental shelf sea connected with the Boreal and the Tethyan oceans. The pronounced facies architectures of Lower to Middle Jurassic coastal-deltaic and basinal deposits challenged many workers to apply sequence stratigraphic methods. However, resulting regional schemes are in places contradicting, which is caused by both common problems with precise dating and processes of regional to local scale obliterating the sea-level signal, such as tectonically enhanced subsidence, enhanced sediment supply, thermal doming, or salt diapirism. This paper proposes a Lower to Middle Jurassic sequence stratigraphic framework of the NGB. The application of a multi-method approach, including intensive macro- and micropalaeontological dating as well as mapping of biofacies and lithofacies architecture to an extensive data set of cored and logged wells resulted in a hierarchical framework of 2nd-, 3rd-, and 4th-order epicontinental sequences. This approach enabled the identification and exclusion of areas and locations where subordinated controls, such as salt diapirism, superimposed the signature of sea-level fluctuations within stratal pattern architectures. The proposed sequence stratigraphic framework correlates well with the Boreal Standard but to much lesser extent with the Tethyan Standard and, thus, demonstrates the principle control of Boreal cycles on epicontinental stratal pattern architectures of the NGB. This coincides with more significant faunal exchanges between the Boreal and Subboreal provinces. In particular, the opening of a marine strait via the Russian Platform in the late Middle Jurassic enabled the immigration of Boreal ammonites and ostracods into the NGB and the northern CEB and illustrates the change from a semi-enclosed inland sea to a continental shelf sea. Furthermore, the recognition of Lower and Middle Jurassic 4th-order sequences supports suggestions of glacio-eustatic sea-level changes in the Jurassic.

The delta region of the Amu-dar'ya has a complex history of shifting river channels that has impacted extensively on the Aral Sea and on the areas of the delta that saw human settlement from prehistoric times onwards. This paper explores evidence drawn from archeological, historical and environmental data relating to lakes that formed in the south of the delta on the east bank of the river and their impact on settlement patterns in this area, in particular the potential impact of variable flooding on the major fortified site of Akchakhan-kala. Testing of the area around the sites showed that the site had not been flooded but was founded on riverine or lacustrine clays. Shortly after the initial abandonment of the site, the immediate environment was covered by dune fields.

Glacial sediment is an important paleoclimatological and paleoenvironmental archive. In the Mediterranean region most of the Quaternary glaciers were hosted in carbonate mountains. Diagenetical processes in carbonate sediments tend to impact preservation of glacial features and complicate the establishment of accurate chronologies. This paper presents a sedimentological study of a paleoglacier hosted in the carbonate Velebit Mountain, Croatia. Three carbonate tills were studied in order to evaluate their depositional environments and the diagenetical processes that affect them. The tills were selected from lateral moraines of different glacial stages of the paleoglacier and they are interpreted as lodgement and melt-out tills. Diagenetical processes such as cementation, dissolution and increase in organic content were enhanced by the percolation of water through the sediment and the propagation of rootlets. This research demonstrates the importance of understanding the diagenetical processes affecting carbonate tills after their sedimentation. Studies like this are an essential research stage prior to conducting geochronological and paleoclimatological interpretations based on paleoglaciers in carbonate regions.

Volcanic islands are unique contexts to analyze the controls on calcrete development in settings with varied relief, climate and vegetation, and lacking carbonate host rocks. This paper discusses the formation of Quaternary calcrete profiles in Gran Canaria volcanic Island, under direct influence of the SAL (Saharian Air Layer). Calcrete profiles are multi-storey and composed of prismatic, massive, laminar, pisolithic, ooid-bearing, sandy mudstones with rhizoliths and brecciated horizons. Host rocks include basalts, siliceous mudstones, volcanic sands and gravels and bioclastic-rich sands. Carbonate is mostly calcite but some dolomite occurs in massive horizons. The main microfabrics include laminated micrite, fine crystalline dolomite, desiccated micrite, micrite-clay groundmass, oriented Mg-rich clays, peloids, spherulites and coated grains. δ13C varies from −3.26 to −9.18‰ VPDB and δ18O from +0.86 to −3.24‰ VPDB. The 87Sr/86Sr ratios are between 0.707504 and 0.708860, indicating that calcium was mostly supplied from the CaCO3-rich aeolian dust coming from the Sahara Desert. Calcrete profiles are mostly pedogenic with roots and microorganisms enabling carbonate precipitation within the soils. The correlation trend of δ13C and δ18O points to a climate control on precipitation, with the heavier isotope values in the horizons containing dolomite. Sedimentation rates interplayed with calcrete formation processes and erosion to outline the profiles/horizons. Amalgamated laminar horizons formed when the rate of calcrete formation was higher than sedimentation and erosion, whereas areas or periods with relatively higher sedimentation allowed the separation of calcrete horizons. The direction of the winds supplying aeolian dust, and the varied relief, vegetation and climate favored better development of calcretes in the relatively arid and lowland areas of the eastern side of the island. Our study shows that calcretes contain the record of the paleoenvironmental controls that operated in volcanic islands with no previous carbonate substrates.

Little is known about the climate and environmental changes that have occurred in the extremely arid regions of China since MIS (Marine Isotope Stage) 3 (59–29 cal kyr BP), when most regions in northwestern China and the Tibetan Plateau featured warm and humid conditions. In this paper, we present a record of the climate changes in the Qaidam Basin in arid northwestern China over the past 40 kyr based on the mineralogy of a 35-m-long sediment core recovered from Qarhan Salt Lake. Our results show that the lake was a saline or hyper-saline lake saturated with respect to gypsum between 40 and 33 cal kyr BP. Beginning at 33 cal kyr BP, evaporite formation was dominated by halite precipitation, indicating that the lake salinity had increased extensively and that the climate became drier during 33–24.5 cal kyr BP. The lake salinity then increased continuously, resulting in the appearance of bischofite between 24.5 and 14.6 cal kyr BP. The disappearance of bischofite and the increase in gypsum indicate that the salinity of the water decreased slightly between 14.6 and 8.3cal kyr BP. However, during the last 8300 years, the lake has dried up and is now a playa. Generally, the climate was wet in late MIS 3, arid in MIS 2 (29–11.7 cal kyr BP), and hyperarid in the Holocene. The relatively humid conditions may have resulted from weak evaporation caused by the relatively low insolation and intense ice-albedo feedback in late MIS 3. The decreased insolation and dramatically increased Eurasian ice volume in MIS 2 may have led to limited precipitation, which resulted in persistent dry climate conditions in the Qaidam Basin. In the Holocene, the reduction in ice volume reduced the albedo, and this change, in conjunction with increased insolation, may have led to evaporation exceeding local precipitation, resulting in hyperarid climate conditions in the Qaidam Basin.

This paper presents pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves in southern Spain (Granada), with the aim of reconstructing the environmental conditions of these hominin sites. The LV coprolites are radiocarbon dated from c. 37,890 to 6980 cal yr BP, and the Car coprolites from c. 31,063 to 7861 cal yr BP. Overall, the palaeoecological scenario inferred from both coprolite series display similar patterns, with Pinus, Poaceae, and Artemisia as dominant during the full Pleistocene, and an important contribution of Quercus in the most recently dated coprolite samples. While the palynology is consistent with results of former investigations on the past environments in the region as obtained from other deposits (peat bogs, cave infills), the Late Glacial and Holocene chronology of several coprolites in both sites is in conflict with the generally accepted timing of extinction of Crocuta in western Europe. A discussion on the taphonomical processes and potential sources of carbon contamination of the radiocarbon samples is provided. The correlation between pollen from coprolites and from sedimentary records, and the paucity of the fossil bone record suggests nevertheless, that a late survival of Crocuta in southern Spain should not be categorically discarded.

Extinct giant ground sloths are a common taxon in New World Quaternary deposits, but relatively little is known about individual species' behavior or social structure. In this paper, we investigate the development of the late-Pleistocene locality Tanque Loma on the southwest coast of Ecuador, which preserves remains of at least 22 individuals of the giant ground sloth, Eremotherium laurillardi in asphaltic sediments. Multiple lines of evidence suggest that these sloths may have congregated and died in a mass mortality event in a marshy riparian habitat. Such evidence includes (1) a dense, laterally-extensive, bonebed-style accumulation; (2) a multigenerational age structure with adult and large juvenile individuals well-represented; (3) sediments suggestive of a low-energy anoxic aquatic environment; and (4) the presence of abundant plant material consistent with digested fodder representing coprolites or gut contents of E. laurillardi. Taking observations from modern megafaunal ecosystems as an analogue, we suggest that this death event could have resulted from drought and/or disease stemming from the contamination of the wallow, paralleling situations observed among hippopotamus populations in watering holes on the present-day African savannah.

The 60-year quasi-periodic variability of the Asian monsoon in the mid-late Holocene has been found to be widespread in instrumental and various terrestrial records. However, whether this period exists in the older interglacial periods remains to be further studied. This paper is based on an 1840-mm-long stalagmite with clear annual laminae (with a growth rate of about 1 mm/yr) from Yongxing Cave, China, that allows for the reconstruction of the Asian monsoon evolution sequence during the period ~123.20–121.21 kyr BP. The stalagmite record closely tracks the 65°N solar insolation changes as a whole, indicating the dominant control of solar insolation on the Asian summer monsoon. After removing the solar insolation signal from the YX108 record, the δ18O residuals (Δδ18O) show 28 multidecadal monsoon cycles. The average amplitude of these fluctuations is larger than 0.8‰, with a duration typically ranging from 50 to 80 yr (about 64 yr on average), which is very similar to the mid-late Holocene Asian monsoon variability. Further, wavelet analysis displays a significant quasi-periodicity of 60 years throughout the studied period, providing further evidence for assessing whether the 60-year quasi-periodic variability of the Asian monsoon found in the Holocene exists in older periods. Our study thus suggests that this quasi-periodic variability not only occurred during the modern period but also existed in the Last Interglacial, and their influence may even be an intrinsic characteristic of the Asian monsoon system during glacial-interglacial cycles. We manifested that the interactions between solar activity and the Atlantic Multidecadal Oscillation may be the main reason for the 60-year quasi-period of the Asian monsoon.

The proboscidean Notiomastodon platensis is widely recognized in the Pleistocene of Brazil, but direct evidence for its feeding behavior is scant. In this paper, we report palynological assemblages preserved in dental calculi to infer dietary preferences and habitats. Molar specimens (m1 and M3/m3) with significant calculus accumulation were examined from localities along the Coastal Plain (CPRS) and the Campanha region (western state in Pampa biome) in Rio Grande do Sul state, southern Brazil. Palynomorphs obtained from calculus were identified with light microscopy, and we applied species distribution modelling (SDM) for arboreal/shrub pollen taxa to investigate the environmental contexts for proboscideans during the Last Interglacial (LIG, 120 ka BP) and Last Glacial Maximum (LGM, 21 ka BP). Pollen assemblages indicate a generalist diet for N. platensis, and corroborate previous paleoecological studies. N. platensis from CPRS showed two patterns: the subadult individual was a specialized browser in wooded habitats, inferred from pollen taxa dominated by arboreal species (mainly Myrtaceae), while mature/senile adult individuals were dominantly grazers to mixed-feeders in open habitats inferred from herbaceous pollen (mainly Cyperaceae) mixed with woody elements. For the Campanha region, diet interpretation is difficult due to the absence of pollen; however, Poaceae phytoliths indicate that grasses may have been important food items, notably pooid C3 grasses. N. platensis potentially accessed a more heterogeneous environment with mixed open grasslands and forests around the LIG interval because of the larger extension of forest at the time. Grassland landscapes could have been more foraged by proboscideans around the LGM given the dry and cold climate conditions, which resulted in a northward retraction of forest.

Late Cenozoic sediments in the Linxia Basin of China, on the northeastern Tibetan Plateau, bear abundant fossils of the Hipparion fauna. From late Miocene times, these sections record a history of aridification in the Asian Interior, the evolution of the east Asian monsoon, and multiple uplifts of the Tibetan Plateau. In this paper, a new detailed magnetostratigraphic study of a sedimentary sequence from the Duikang (DK) section containing the Hipparion fauna is presented, to better understand interconnected ecologic and environmental changes. The 90-m-thick section reveals nine normal and nine reversed zones that span from chron. C5n.2n to chron. C3Ar or from chron. C4n.2n to chron. C2Ar, yielding magnetostratigraphic ages of ~8.1 Ma - 3.7 Ma for the studied section and 5.3 Ma for the Hipparion fauna-bearing bed. Combined with all the previous magnetostratigraphic ages of the fauna-bearing sediments in the Linxia Basin, Hipparion can be distinguished as mainly having lived during five periods: Phase I (11.5 Ma), Phase II (8.2 Ma), Phase III (6.3 Ma), Phase IV (~5.3 Ma) and Phase V (2.5 Ma). Based on comparison of climate records in the Linxia Basin with aridification records from surrounding regions and global cooling during the late Cenozoic, we suggest that the evolution of Hipparion from the Linxia Basin was mainly driven by continuous global cooling and tectonic uplift of the northeastern Tibetan Plateau since the late Miocene.

In this paper, 5 schemes for reconstructing the sea ice conditions in the Sea of Okhotsk (the SO) during the last 74 kyr are presented. These schemes were constructed based on calculations of the ice rafted debris (IRD) fluxes in 16 sediment cores and the available published mineralogical data ( Derkachev et al., 2004 ). We obtained new data on the orbital-scale changes of the IRD fluxes in the studied area for the last four marine isotopic stages (MIS). As a result, the key areas of sea ice formation and general direction of sea ice drift and, in turn, dominate direction of geostrophic wind in the SO were established for each of the investigated MISs. It allows us to suppose the positions of Siberian High and Aleutian Low during the individual MISs. At that, the sea ice was of predominantly seasonal for studied period, except for the northwestern and western parts of sea, where perennial sea ice fields were preserved over a period of several years during MIS 2. The variations of sea ice conditions attest to a particular type of atmospheric pressure field prevailing over the SO during individual MISs. The secondary sea ice drift directions points out that the predominant atmospheric pressure field during individual MISs were inconstant except the MIS 2.

The occurrence of striated floors, produced by the Gondwana ice sheets, is briefly described in this paper. Several striated localities crop out in the second plateua of the State of Parana (Brazil), some of them being unusually well preserved. The striations occur on pre-Gondwana surfaces of the Devonian Furnas Formation, as well as on the periglacial deposits of the Itaare Formation (Upper Carboniferous), which also bears the glacial sequences. Many outcrops are directly overlain by typical tillites, making possible a comparison between the direction of the glacial lineations, and the long axis pebble orientation of those rudaceous deposits. The average pebble long axis dip direction for the Cancela Tillite is S 11 ° E, while the glacial striations direction is S 2° E, the difference being only 9°. The ice movement deduced for the Cancela Tillite was toward N 11 ° W. Besides the results obtained from the tillite fabric, additional data were gathered from sedimentary structures of the periglacial deposits. Thus, crossbedding measurements, carried on in the outwash sandstones associated to several Gondwana glaciations, afforded the following average result: N 5° W. General results, as compared together, show a reasonable agreement between both the results of glacial deposits and of the periglacial ones. As the present writers are gathering more data, it is assumed that definite and more reliable results may be given in forthcoming papers.