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Chu et al. (2015, Lilliput effect in freshwater ostracods during the Permian–Triassic extinction) reported a sharp decrease of the size of freshwater ostracods through the terrestrial end-Permian extinction (EPE) interval of the Dalongkou Anticline section in Northwest China. The proposed work is however unacceptable because of taxonomic and methodological issues. Most of the identifications are rejected because of too poor preservation and generic misidentifications due to the unawareness of the abundant literature published for years on Permian freshwater ostracods. The proposed analysis of the size of the misidentified genus Darwinula considers the totality of the recovered specimens but is meaningless by ignoring the aspect of the ontogenetic development of ostracods. As a consequence, the observed reduction of size of ostracods could be related to changes in the taphonomic conditions or in the proportions of juveniles under special environmental, which have already been suggested for marine ostracods through the EPE.

Benthonic marine species show a wide range of biological reactions to seawater chemical changes through time, from subtle adjustments to extinction. The Early Toarcian Oceanic Anoxic Event (T-OAE) was recently recognized in the Neuquén Basin, Argentina, confirming its global scope. The event was identified chemostratigraphically on the basis of a relative increase in marine organic carbon and a characteristic negative carbon-isotope excursion (δ13Corg) in bulk rock and fossil wood in the upper Pliensbachian–lower Toarcian interval in the Arroyo Lapa section (Neuquén). Simultaneously with collection of lithological samples, a high-resolution biostratigraphical survey was carried out, and the scarce benthonic fauna was collected in order to check the biotic response to changing marine geochemical conditions. We present here an analysis of size and abundance data from the T-OAE interval in the Neuquén Basin for the dominant bivalve species, the paper-clam Posidonotis cancellata (Leanza), and relate these data to geochemical proxies (%TOC and δ13Corg) obtained at the same locality. The abundance of P. cancellata increased when the rest of the benthos diminished, reaching a maximum at the onset level of the T-OAE, and then decreasing. Size-frequency distributions show a noteworthy lack of juvenile shells. Shell size shows a positive correlation with %TOC in the whole section, though over the T-OAE interval proper, it decreases below the level where the maximum %TOC value is attained and increases above it. Posidonotis cancellata shows features of opportunistic species, such as high tolerance to hypoxia, strong dominance in impoverished environments and a strong dependence on primary productivity, but at the same time had a reproductive strategy more similar to equilibrium species, with relatively low juvenile mortality rates. Several anatomical features suggest adaptation to permanently dysaerobic environments. The species disappeared just before the minimum negative carbon-isotope value was reached; and by the same time the genus became extinct worldwide. Fil: Ros Franch, Sonia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Echevarría, Javier. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Damborenea, Susana Ester. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Manceñido, Miguel Oscar. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Jenkyns, Hugh C.. University of Oxford; Reino Unido Fil: Al Suwaidi, Aisha. Khalifa University Of Science And Technology; Emiratos Arabes Unidos Fil: Hesselbo, Stephen P.. University of Exeter; Reino Unido Fil: Riccardi, Alberto Carlos. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina

A high-precision geologic time scale is the essential key for understanding the Earth’s evolutionary history and geologic processes. Astronomical tuning of orbitally forced stratigraphic records to construct high-resolution Astronomical Time Scales (ATS) has led to a progressive refinement of the geologic time scale over the past two decades. In turn, these studies provide new insights regarding the durations and rates of major Earth events, evolutionary processes, and climate changes, all of which provide a scientific basis for contextualizing and predicting future global change trends. South China hosts some of the best-exposed and well-dated Neoproterozoic through Mesozoic stratigraphic sections in the world; many of which are suitable for cyclostratigraphy and calibrating the geologic time scale. In North China, several Cenozoic oil-bearing basins have deep boreholes with continuous sampling and/or well logging that enable derivation of astronomically tuned time scales for an improved understanding of basin evolution and hydrocarbon generation. This Special Issue focuses on case studies of astrochronology and applied cyclostratigraphy research using reference sections within China. In this introductory overview, we: (1) summarize all existing astrochronology studies of the Neoproterozoic through Cenozoic sections within China that have been used to enhance the international geologic time scale, (2) examine briefly the astronomically forced paleoclimate information recorded in various depositional systems and the modern techniques employed to analyze the periodicity of these signals encoded within the sedimentary record, and (3) summarize the 20 contributions to this Special Issue of Palaeogeography, Palaeoclimatology, Palaeoecology on 'Cyclostratigraphy and Astrochronology: Case studies from China’.

Charcoal is produced by pyrolysis of plant material and its occurrence in the fossil record can be broadly equated with the incidence of palaeowildfire. The past record of such naturally occurring fire, and tha availability of the biomass which represents its fuel, put two constraints on oxygen levels. For combustion of plant material to occur at all requires that the atmospheric oxygen did not drop below a threshold of 13%. Increasing inflammability of plant material at higher oxygen levels suggests that 35% would be a ceiling above which plant biomass would ignite and burn so readily as to be incompatible with sustained forest growth. As we have more or less continuous fossil evidence of forest trees from the Late Devonian onwards, and a similarly sustained record of fossil charcoal from that time to the present (Cope, 1984), this constraints oxygen levels between 13% and 35% over that period (Rabash and Langford, 1968; Watson et al., 1978). However, further experimental work is required to establish the validity of these oxygen values under appropriate conditions and also to sharpen the certainty by which we can discriminate between fusain produced by pyrolysis, and inert wood degradation products produced by other (? biogenic) means. We discuss experiments directed at attempting to establish the validity of physical parameters by which pyrolytically produced fusain can be characterized. The most convincing evidence of pyrolysis hitherto recognised is the apparent homogenization of xylem cell walls, as seen under SEM. Work on charcoal from both wildfires and laboratory wood charring under controlled conditions confirms the homogenization as seen under both SEM and TEM. Controlled temperature experiments show that a further rise in temperature causes the cell walls, initially homogenized, to crack and separate along the site of the middle lamella, giving the charcoal a characteristic fibrous texture. Both of these distinctive phases of response to pyrolysis can be observed in fossil charcoals.

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.

In this paper, we conduct a palynological analysis of a high-resolution Holocene record from Cartagena Bay, southeast of the Iberian Peninsula, to establish paleoenvironmental variability of coastal areas in the western Mediterranean region at a centennial-scale over the last 7300 years. Statistical analysis of four palynozones allows reconstruction of paleotemperature and paleohumidity conditions. Pinus, steppic, xerophilous, and Mediterranean taxa persisted continuously through the record, and only during periods of increased humidity did deciduous and Mediterranean taxa expand (Zones II, subzone IIIb). Cooler and dry conditions favored the development of Cupressaceae and scrubs between 7300 and 7000 yr cal BP. The mid-Holocene (Northgrippian) mesophytic optimum took place between 6800 and 4000 yr cal BP during which time a Mediterranean climate was present and open forest developed, predominantly consisting of Mediterranean taxa and deciduous trees. The gradual rise in aridity in the Meghalayan (4000–1700 yr cal BP) led to Mediterranean forest being replaced by steppic and xerophilous vegetation, a change related mostly to a decrease in summer insolation, with superimposed centennial-scale variability in humidity. In parallel with forest degradation caused by increasing aridity, the record shows marked evidence of human influence since 4000 yr cal BP, which accelerated the progression of open landscapes from the Chalcolithic onwards, this change being especially marked during the Roman period. Significant denudation of the landscape can be attributed to the use of fire, as well as due to agriculture and grazing, with a major contributor being intense metallurgical and mining activity in the area. The Cartagena Bay record reported herein shows centennial-scale oscillations in humidity and temperature that correlate with well-known climatic events during the late Holocene in the western Mediterranean region, synchronous with variability in solar and atmospheric dynamics. The alternation of persistent North Atlantic Oscillation modes is likely to have played a key role in regulating humid–arid periods., This paper was made possible by Grant HAR2017-85726-C2-2-P (Cambios ambientales y ocupación humana en el sector central del sureste ibérico) funded by MCIN/AEI/10.13039/501100011033 and by Grant HAR2017-85726-C2-1-P (Carthago Nova desde su entorno litoral: Paleotopografía y evolución medioambiental del Sector central del Sureste Ibérico. Dinámica poblacional y productiva) funded by MCIN/AEI/10.13039/501100011033

Because the instrumental record is short and does not extend to periods before the initiation of significant human impacts, full understanding of the processes and dynamics involved in the modern phase of very rapid global change depends on the interpretation of high resolution and precisely dated proxy archives. The identification of very long-lived species of bivalve mollusc in the extratropical marine environment has been a crucial recent advance. These molluscs form patterns of periodic (usually annual) banding in their shells that are synchronous within populations, so that long (centennial and millennial) stacked chronologies can be built by crossdating from live collected to fossil shells. The variable growth rates and precisely dated geochemical data from the shell material provide long term real world data that can in principle be used to constrain climate models and to define long baselines for environmental monitoring. However, the signals in these data usually result from the complex interaction of multiple influences, and the deconvolution and understanding of these influences is a major target of the scientific field of sclerochronology. This special issue presents some of the latest research into the sclerochronology of mollusc shells. It includes contributions to our understanding of shell growth, including the identification of endogenous (non-environmental) growth rhythms that persist throughout ontogeny, and analysis in two papers of variability through ontogeny in the season of growth and the implications of such variability for temperature reconstruction. One paper presents a new network of bivalve chronologies for UK waters, with a 200-year seawater temperature reconstruction. Three papers cover trace element geochemistry, including a novel approach to sampling for LA-ICP-MS that enables giant clam shells to be sampled at daily resolution, an attempt to identify an independent temperature proxy for coastal waters using limpet shells, and a detailed study of the drivers of variability in Sr/Ca and Ba/Ca ratios. One study looks at shell microstructure as a temperature proxy, finding a coherent temperature response in the shape of the prisms.

This paper is a review article focussing on the research on past environments of Zimbabwe. The paper synthesises the current knowledge on palaeo-climates and other environmental parameters that inform debates and discussions on climate change and human adaptation. The study of palaeoenvironments provides environmental knowledge that chronologically goes beyond the range of written climatic records that are available in the country. The palaeoenvironmental data now available shows that our human ancestors in Zimbabwe have survived numerous climatic upheavals since the beginning of the Stone Age. However, limited research in the Stone Age and the variety of proxy data available creates a less coherent record. Extrapolation of evidence from the region makes the data less reliable for archaeological interpretations. The paper shows conflicting signals across the region at some specific periods. There are numerous gaps in the record. The paper concludes by calling for multidisciplinary research on the past environments of Zimbabwe.

In the comment on our paper, Cho and Cheong (2016) and Kim and Ree (2016) make a number of arguments that we did not discuss the Cambrian zircons from our data and have cast doubt on our early Cambrian paleogeographic reconstruction. They also argued that our data do not pass statistical tests between concerned strata for paleogeographic reconstruction. In response to the comment, we show that these arguments are not based on sound geological evidence and conditions that we provided in our paper.

With the discovery of the Bozhong 19–6 large gas field in the Bohai Bay Basin, the study of lacustrine source rocks in the southwestern Bozhong Sag has garnered new interest. In this paper, 107 source rock samples of the Paleogene Shahejie Formation (Es) from the southwestern Bozhong Sag were analyzed with organic and inorganic methods and compared with other sags in the Bohai Bay Basin to reveal the depositional environment and controlling factors of organic matter enrichment during the deposition of the Es. The formation of source rocks (average total organic content = 2.76%) was subject to a combination of high organic productivity and enhanced organic preservation. Also, this was reflected by the existence of nutrient elements of P and Ba as well as other high productivity-related elements such as Cu, Zn, and Ni. The moderate Mo enrichment factor, Pr/Ph and low to moderate (C/P)org ratios were an essential part of this organic preservation. Moreover, the evidence we observed for the existence of hydrothermal activities consisted of high contents of quartz and pyrite, large positive Eu anomalies, and enrichment of elements related to hydrothermal fluids. Hydrothermal influence may lead to similarities and fluctuations in water salinity, organic productivity and preservation in the third (Es3) and first (Es1) members of the Es. Hydrothermal fluids may play an essential role in promoting the development of high organic productivity, stable reducing environment, and brackish water (as shown by the range of B/Ga and TS/TOC) in the lakes during the source rock deposition. This paper may provide implications for gas accumulation mechanisms and a complete set of organic and inorganic experimental data for source rock analysis in other lacustrine rift basins.

The stable oxygen isotope composition of phosphates (δ 18 O P ) extracted from vertebrate bone and teeth material is widely used for paleotemperature reconstruction over the Quaternary period. However, inconsistency in analytical and statistical procedures used by different researchers for recalculation of mean air temperatures from measured δ 18 O P values makes integration of different data sets challenging. Therefore, consistency in both stable isotope data processing and the application of appropriate statistical procedures is highly desirable. This paper evaluates the uncertainty associated with two most commonly used regression methods, least-squares inverted fit and transposed fit. We assessed the performance of both fits by designing ‘real-life’ experiments using various data sets. We used both regression models to reversely calculate the differences between actual recorded in ‘real-life’ values and values calculated from the regression models. Our calculations clearly show that the mean absolute errors are always substantially higher for the inverted fit and the transposed fit always returned mean values closer to the values measured in ‘real life.’ In all studied scenarios, the predictive models performed better than causal models, returning mean absolute errors by 12–65% lower. In the paper, we also examined the other main sources of uncertainty, concerns about calculation of δ 18 O P of phosphates from δ 18 O C of carbonates, averaging of δ 18 O W in precipitation and highlight major challenges in the field of phosphate stable oxygen isotope biogeochemistry. The estimation of paleotemperatures from isotope records could be improved by employing globally consistent calculation procedures.

The paleoichnological site of Pehuen Co, located on the southern coast of Buenos Aires province, Argentina, was discovered in 1986 and the first paper was published in 1987. New discoveries made in the following years have revealed well-preserved Pleistocene mammal and bird footprints of high diversity. Investigations at this site have continued to the present. The most important aim of this paper is to revise the previous ichnotaxonomic assignations, and to present some new discoveries. The described tracks include eleven mammal (Neomegatherichnum pehuencoensis, Mylodontidichnum rosalensis, Glyptodontichnus pehuencoensis nov. igen. and isp., Eumacrauchenichnus patachonicus, Proboscipeda australis nov. comb., Dolichotichnus marae nov. igen. and isp., Ursichnus sudamericanus nov. isp., Hippipeda isp., Lamaichnum guanicoe, Lamaichnum tulipensis nov.comb, Pecoripeda commune nov. comb.) and four bird icnotaxa (Phoenicopterichnum pehuencoensis, Charadriipeda isp., Gruipeda isp., and Aramayoichnus rheae nov. igen. and isp.). The second goal of this paper is to emphasize the worldwide significance of the Pehuen Co site relative to other Pleistocene vertebrate tracksites. Pehuen Co site is unique because of the quality of preservation, and the abundance and diversity of the footprints.

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

As an important tool in natural resource exploration, palaeogeography provides a portrayal of deep time Earth. The South China Block located in the eastern Palaeotethys includes multiple natural resources (e.g., coal, shale gas, bauxite, etc.) in the Permian, which are well known for their important economic significance. In this paper, data gathered from literature amount to 431 stratigraphic sections of Wuchiapingian age from South China. These data were quantitatively analyzed and dynamically reconstructed in the global context under the revised plate motion model by GPlates software for the first time. A schematic 3-D model was constructed based on the high-resolution reconstructions in this paper, showing two relatively large highlands developed in the South China Block during the Wuchiapingian, including the Kangdian Highland in the west and the Cathaysia Highland in the east and a small Yunkai Highland in the south. A broad platform-dominated depositional system with small uplifts and depressions was developed between these two highlands. These reconstructions show great potential to explore enriched coal seams and shale gas in the peripheral areas of the two ancient highlands in the west and east of the South China Block. Based on the dynamic evolution of this depositional system, South China experienced an overall sea-level rise with frequent secondary transgressions and regressions during the Wuchiapingian. This is in contrast to the widespread continental and evaporite deposits on much of Pangea and its surrounding margins after the end-Guadalupian global regression. Compilation of conodont biostratigraphic data suggest that the temporal and spatial constraints on the unconformity across the Guadalupian-Lopingian boundary (GLB) resulted from Dongwu Uplift movement. The regression began during the Jinogondolella shannoni Zone and ended in the Clarkina leveni Zone, but the response time varies in different localities of South China. These results provide detailed information about sea-level eustacy, tectonic uplift, sedimentary hiatus, resource accumulation and palaeoclimate change from the South China Block during the Wuchiapingian.

The Permian formations of the South African Karoo Basin play a crucial role in understanding Gondwana's climate history during this time of major global changes. In this paper we present two data sets, one from the coal-bearing Vryheid Formation (Witbank Basin) and one from the Whitehill and Upper Prince Albert formations of the DP 1/78 core (NE Karoo). Our main goal was to study the vegetation changes during this period of global warming and test if the climatic signals could be used to correlate the basinal Ecca group facies with the fluvio-deltaic coal-bearing strata of the Witbank Basin. The palynological record of the No. 2 Coal Seam of the Vryheid Formation indicates a cold climate, fern wetland community, characteristic of lowland alluvial plains, and an upland conifer community in the lower part of the coal seam. Up section, these communities are replaced by a cool-temperate cycad-like lowland vegetation and gymnospermous upland flora. The data set of the DP 1/78 core is interpreted to represent a cool to warm temperate climate represented by a high amount of Gangamopteris and Glossopteris elements. Both data sets are very different in their composition, which can be explained by the differences in depositional environment; however, our findings reveal a different age of the studied assemblages and thus also suggest that both data sets represent different stages in the transition from icehouse to greenhouse during Permian times. As the stratigraphic correlation between the Main Karroo Basin and the peripheral basins is still under discussion, this paper provides new data to underpin the stratigraphic placement of the Whitehill Formation relative to the coal-bearing Vryheid Formation.

The early Tournaisian (Carboniferous) stage represents a key episode in the evolution of vertebrates. It follows the end-Devonian Hangenberg extinction event, which led to a major perturbation to both terrestrial and aquatic vertebrate ecosystems, and resulted in a significant restructuring of assemblages. However, few faunal associ-ations of this age have been described, and our understanding of faunal turnover across the Devonian -Carboniferous boundary remains poor. In this paper, we present an analysis of coprolite material from early Tournaisian lacustrine facies at Celsius Bjerg on Ymer o in East Greenland, which overlies the world-famous latest Devonian tetrapod-bearing localities. Fifty-five coprolite specimens (defined as a single coprolite or a piece of shale containing coprolites) were analysed using propagation phase-contrast synchrotron micro -tomography (PPC-SR mu CT). Through a study of external morphology, shape and size combined with information about internal structures, we categorise coprolite morphotypes, and interpret their origin. Notably, we identify a greater number of coprolite morphotypes compared to vertebrate taxa known from skeletal material, indicating the existence of a cryptic ecosystem that has not yet been recovered as body fossils. Vertebrate diversity in the immediate aftermath of the end-Devonian extinction is inferred to have been higher than expected, and might have included transient faunal elements within an open system, perhaps involving marine basin connections. Our results show that coprolites offer an alternative fossil data source, revealing diversity that is otherwise not always captured by the skeletal record.

In the comment on our paper, Forel and Crasquin (2015) make a number of very strong criticisms that attempt to cast doubt on everything in our study. We thank them for their detailed discussion of our paper, especially the taxonomic and methodological issues and the insightful explanations on the causes of the reduction of ostracod size. However, many of their criticisms are excessive. Our paper focused on the change of ostracod size across the Permian–Triassic boundary according to reliable data, and several probable causes were presented. We accept some of the comments by Forel and Crasquin (2015), but these do not negate the core conclusions of our original paper.

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

In this paper, we describe a 5500-year long core obtained from a lake in the Prealps of northern Italy to investigate the impact of human communities on the lacustrine environment. Specifically, we report micro-botanical proxies (upland and aquatic pollen, algae, cyanobacteria, dung spores, microcharcoal particles), sedimentary parameters (LOI steps, calcimetry, FTIR spectra) and nutrients (P forms, C/N and K) on paired samples in a high-resolution stratigraphy, dated by 14C AMS dating and tie point correlation. Independent archaeological evidence indicates the existence of lakeside settlements and farming in Bronze Age times from c. 4000 to 3300 cal yrs. BP. The impact of this Bronze Age village is recorded by an accumulation of plant detritus, pollen, charcoal and abundant wood and bone-derived ash. Intensive P mineralization by ash production was accompanied by the rapid burial of Pinorg, K, and microcharcoal. Correlated peaks of Porg and pasture plant pollen mark the contribution of animal husbandry to Porg lake sink. The nutrient flux produced by external catchment cropping contrasts with the internal flux discharged by prehistoric dwelling and in turn distinguishes domestic hearth production from a contribution by animal husbandry. Forest conditions and lake sedimentation returned to semi-natural baseline at the end of this 700-year long phase of Early to Middle Bronze Age settlement, but pollen proxies indicate that lake-side forests did not fully recover. Lake Lucone represents a key site, since it documents interactions between bronze Age settlements and related ecological impacts on both terrestrial environment and lacustrine sedimentation, as recorded in a continuous sequence, as well as the end of Bronze Age pile dwelling culture.

Altres ajuts: CERCA Programme/Generalitat de Catalunya The Guadalupian was a key epoch for the evolution of tetrapod faunas. It includes the earliest unambiguous occurrences of therapsids and stereospondyls (groups that later became dominant in terrestrial and freshwater environments, respectively) and the late Capitanian mass extinction event. The low-latitude faunas from this time interval, where sufficiently dated, comprise rare tetrapod body fossils whereas the most complete records are provided by ichnoassociations, especially coming from the Provence basins of France. In this paper, we revise the tetrapod ichnoassociation from the Pélitique Formation of the Le Luc Basin of Provence, identifying the following tetrapod ichnotaxa: Batrachichnus salamandroides (temnospondyls/lepospondyls), Capitosauroides talus comb. nov. (therocephalian therapsids), Dicynodontipus isp. (cynodont therapsids), Varanopus isp. (bolosaurian parareptiles), Hyloidichnus bifurcatus (captorhinomorph eureptiles) and Rhynchosauroides isp. (neodiapsid eureptiles). According to our revised ichnotaxonomy and stratigraphic correlations, we date the Pélitique Formation as late Capitanian and assign its tetrapod ichnoassociation to the newly defined Association V (Dicynodontipus sub-biochron of the Erpetopus biochron). The Pélitique Formation ichnoassociation shows a typical composition for a post-dinocephalian extinction ichnofauna, as shown by preliminary multivariate statistics on Guadalupian-Lopingian tetrapod ichnoassociations. It is similar to the contemporaneous skeletal faunas described from the mid- to high-latitude sites of Russia and South Africa and is arguably the earliest evidence of post-dinocephalian extinction recovery at low-latitudes. Our results confirm the global and abrupt impact of the late Capitanian terrestrial mass extinction and the subsequent recovery in the low-latitude realm. This extinction was probably time-equivalent with a global benthic marine mass extinction, and both events may have been linked to climatic perturbation caused by the Emeishian volcanic activity in China, which reached its peak around 260 Ma.

Microbial bioerosion, in all its manifestations, is one of the major factors determining the long-term survival of archaeologically and environmentally important artefacts and ecofacts made from mineralised collagen – bones, antler, teeth and ivory. The bone diagenesis literature contains extensive descriptions of different morphologies and classifications of microbial bioerosion – microscopical focal destruction, Wedl tunnels, linear longitudinal, budded and lamellate tunnelling, etc. but the causative agents remain to be discovered. Palaeontologists are in a similar situation when describing ichnofossils where bioerosion is classified by its characteristic morphology and only tentatively assigned to specific causes. In archaeological bones, Wedl tunnels have traditionally been ascribed to fungi but a re-examination of Wedl's original paper and subsequent literature has shown that all the early specimens examined came from aquatic environments and that euendolithic microflora (cyanobacteria or chlorophytes) might have been responsible. These microorganisms are known to tunnel into marine shells. Linear longitudinal, budded and lamellate tunnelling have all been ascribed to bacteria. However, analyses using a combination of backscatter SEM (BSEM) and mercury intrusion porosimetry (HgIP) of bones excavated from terrestrial soils suggest that the various tunnelling morphologies described by earlier researchers are actually all manifestations of a single architecture, the differences arising from the inherent variability of bone microstructure and the hydrology of the burial environment. An examination of the BSEM and HgIP data also indicates that the bacteria responsible may spread through dead bone tissues by expanding the canalicular network (or dentinal tubules in teeth) rather than creating new tunnels. Long-term field burial experiments using de-fleshed cow bone specimens have now demonstrated that bacterial tunnelling develops over decades rather than months as was previously thought, even in warm tropical soils. This has obvious implications for the origin of the bacteria responsible (soil bacteria versus endogenous gut bacteria) since the bone specimens were quickly isolated from gut contents. Although no attempt is made here to identify a specific organism or organisms responsible for tunnelling in terrestrial archaeological bones a tentative model is proposed for how cycles of wetting and drying, or changes in local dissolved oxygen levels, could lead a common gram positive soil bacterium to produce the pattern of bacterial bioerosion seen in exhumed bones. This soil organism may act in a similar way to Staphylococcus aureus which proliferates in living bone (causing osteomyelitis) by infiltrating and enlarging the canalicular network.

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.

Bouchal, Johannes Martin/0000-0002-4241-9075; Guner, Huseyin Tuncay/0000-0001-9742-1319 WOS:000478712100017 The early Miocene was a period of major palaeogeographic reorganization in the eastern Mediterranean region, during which time the Anatolian Plateau became subaerial and several intracontinental basins intermittently became connected to the Paratethys and Mediterranean seas. In this paper, we analyse early Miocene vegetation and climate using leaf records, palynological assemblages, and fossil wood at 36 localities from western and central Turkey, most of which have precise age control based on radiometric dating and mammal faunal ages. Using the leaf flora of Giivem (Bes Konak, Kesekoy), Climate Leaf-Analysis Multivariate Program (CLAMP) analyses and Koppen signatures were employed to infer a palaeoclimate typical of modern laurel forest regions. Based on the palynological records, abundance of various pollen-taxa was used as a measure of openness of vegetation and regional presence of major tree taxa. Most pollen floras are dominated by tree pollen (ranging from 85 to 98%) and indicated widespread afforestation. In the pollen diagrams, shifts in dominance from swamp forest elements (Taxodioideae) to well-drained forests (Pinaceae) indicate changes in lake levels or phases of basin development. Such shifts may have been associated with the development of more xeric forest vegetation. Wood anatomical features such as false tree rings further may indicate seasonal climate. Pollen diagrams and macrofossils reflect zonal and azonal broadleaf and needleleaf forest and extrazonal open vegetation. The latter occurred in areas with shallow soils on volcanic rocks or limestone (e.g. cycads, Dracaena), or coastal areas (herb dominance). Taxonomic composition and biogeographic affinities suggest laurel forest as a major forest biome on well-drained soils and ecotones between laurel forest and broadleaf deciduous forest biomes. A comparison with younger floras shows that these are neither more diverse nor more warmth-loving despite an increase in global temperature (Mid-Miocene Climatic Optimum) suggesting bottlenecks during previous (Oligocene) cooler times for warmth-loving taxa. Swedish Research Council (VR)Swedish Research Council; Scientific and Technologicl Research Council of Turkey (TUBITAK), 2219 Post-Doctoral Research Fellowship Program (2017/2)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [1059B191700382] Bob Spicer, Jakub Sakala, and Howard Falcon-Lang provided valuable suggestions to improve the manuscript. We thank the Turkish Ministry of Mining for permission to work at the lignite mines of Can, Soma, Deni, and Tavsanli, and Atay Holding for permission to work in the lignite mine of Sahnall. Financial support from the Swedish Research Council (VR) to TD is acknowledged. HTG was supported by The Scientific and Technologicl Research Council of Turkey (TUBITAK), 2219 Post-Doctoral Research Fellowship Program (2017/2), project no. 1059B191700382.

The chronostratigraphy of the Cuu Long Basin, offshore Vietnam to the south of the Mekong Delta, is poorly understood, especially for the Palaeogene succession. This paper utilises a comprehensive biostratigraphic database from 46 exploration wells to establish a high-resolution sequence biostratigraphic framework for the Oligocene and upper Eocene based on the identification of 36 transgressive-regressive depositional cycles. They are shown to be climate-driven and correlate to 406 kyr ‘heartbeat of the Oligocene’ eccentricity cycles. Their occurrence has been rigorously cross checked against seismic across the basin. This re-evaluation requires the repositioning of the Oligo-Miocene boundary in the Cuu Long Basin from the C seismic pick to the BI.1 seismic pick. By integrating sequence biostratigraphic and seismic datasets, the Oligocene can be seen as characterised by two types of depositional sequence. Firstly, thin and repetitive depositional packages, here termed ‘Sequences’ but perhaps better visualised as parasequences, the deposition of which was controlled by cyclically changing climate. Secondly, much thicker packages, each comprising a succession of parasequences separated by unconformities, and which tie to the main seismic divisions within the Oligocene/upper Eocene and were driven by tectonics. The latter are visualised as 3rd order sequences, with the parasequences forming 4th order sequences. Correlating the succession of parasequences to the 406 kyr ‘heartbeat of the Oligocene’ isotope cycles allows accurate ages to be proposed for each parasequence boundary, and in doing so an accurate time framework is established for the basin. The first sediments may have been deposited during the latest middle Eocene (Seismic group F/G) at the same time as or just prior to the initial stage of faulting prior to the opening of the South China (East Vietnam) Sea, with deposition of seismic group E commencing at about 36.6 Ma during the late Eocene. Unconformities reflecting 3rd order sequence boundaries are dated at 33.4 Ma, 29.8 Ma and 27.4 Ma.

In this paper, the stratigraphic occurrence of n-alkanes (Cn) is investigated in three peat cores (Mildred, JPH4 and McMurray) from the ombrotrophic peatlands in northeastern Alberta, Canada, to determine their origin, biomass input, and paleoclimatic significance. The molecular composition of n-alkanes is dominated by the >C21 medium- to long-chain homologues, with a strong odd over even predominance. A number of n-alkane-based indices (e.g. predominant n-alkane, C23/C29, C23/(C27 + C31), Paq, ACL, and CPI), show changing conditions in the organic matter (OM) input from Sphagnum species or terrestrial vascular plants, which increasingly contributed upwards in the peat profiles, and through time. Paq and C23/(C27 + C31) proxies are similar in the three cores, and allow us to infer vegetation variations that coincide with the climate alternations of the Medieval Warm Period (MWP), Little Ice Age (LIA), and modern Recent Warming (RW). The utilization of ACL-ket and (C23 + C25)/(C27 + C29 + C31)-ket proxies, performed in comparison with n-alkane proxies, further support the biomarker-based reconstructions of paleoclimate variations over recent centuries. This study suggests that n-alkane homologues are sensitive to vegetation and climate changes and thus are reliable biomarkers for tracking past shifts in vegetation and climate variations in peat archives.

In this paper, correlation between modern leaf physiognomy and climate in China are examined, to optimize the use of leaf characters as a palaeoclimate proxy. A large dataset was compiled, recording the distribution of leaf physiognomic characters among 3166 native dicot trees species across 732 calibration grids on a county level. Grids span a range of ecological environments (tropical rainforests to alpine shrubs) across humid areas. Thirteen climatic parameters were included for each grid and 22 leaf physiognomic characters were scored for each tree species. The correlation between leaf physiognomic characters and climatic parameters were calculated based on single linear regressions (SLR) and multiple linear regressions (MLR). Results indicate clear spatial distribution patterns, linked to latitude, exist for all leaf characters, with temperature (Coldest Month Mean Temperature, CMMT) and precipitation (Growing Season Precipitation, GSP) being the main climate controls. Moreover, because leaf characters are more closely correlated with Precipitation during the Three Wettest Consecutive Months (P3WET), rather than with Precipitation during the Three Driest Consecutive Months (P3DRY), seasonal variations in rainfall associated with the Asian Monsoon might especially influence leaf physiognomic characters. Closer correlations between leaf physiognomy and climate are seen using MLR compared with SLR; therefore Mean Annual Temperature (MAT) and Mean Annual Precipitation (MAP) based on MLR equations provide the most promising basis for palaeoclimate reconstructions in China.

Factors affecting cetacean preservation and distribution in ancient sedimentary successions are not well understood. Actualistic studies have focused on coastal and deep marine examples, and little is known about taphonomic processes occurring within shelf environments. In this paper, we integrate sedimentological, taphonomic and palaeontological data for the cetacean-bearing lower Miocene Gaiman Formation from Patagonia, Argentina, to analyse which factors affected the distribution and preservation of cetaceans in several localities of the Southwestern Atlantic. Facies analysis shows that the formation represents a transgressive-regressive stratigraphic cycle, with palaeoenvironments including coastal, storm-dominated shoreface, inner shelf embayment and open inner shelf. Cetacean remains show preservation styles varying from isolated elements to articulated specimens, with nearly all remains restricted to both embayment and open marine inner shelf settings. Two fossil cetacean assemblages are recognized: Assemblage A comprises small-sized odontocetes dominated by Platanistoidea, preserved mostly in inner shelf embayment deposits; and Assemblage B comprises large-sized odontocetes and mysticetes, dominated by Physeteroidea and Balaenopteroidea, preserved mostly in open inner shelf deposits. Cetacean preservation style is controlled by a combination of palaeoenvironmental conditions, such as energy and sedimentation rate, and by biological factors, such as cetacean body plan and its impact on carcass buoyancy. Ecological factors may also explain the stratigraphic distribution of cetaceans between coastal and oceanic assemblages. This novel integrative and multidisciplinary analyses improves our knowledge of cetacean taphonomy in shelf environments. Fil: Cuitiño, José Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina Fil: Buono, Mónica Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina Fil: Viglino, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina Fil: Farroni, Nicolás D.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Geológicas; Argentina Fil: Bessone, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina

Archaeologists and palaeoecologists are increasingly turning to stable isotope analysis (δ13C, δ18O) of fossil bioapatite to examine interactions of human and animal populations. However, relatively few investigations have focussed on the identification of natural variation in comparable modern populations, particularly within the Australian context. In this paper, we present the first modern isotopic reference dataset for Tasmanian bare-nosed wombat teeth (Vombatus ursinus tasmaniensis). Samples for δ13Cbioapatite and δ18Obioapatite measurements were recovered sequentially at sub-monthly resolution from all tooth types. δ13Cbioapatite showed little variation within a seasonal sinusoidal pattern within the sample set (n = 24 wombats; 35 teeth) due to the homogeneous C3 distribution of plants in Tasmania. In contrast, δ18Obioapatite profiles varied seasonally, representing time periods of between 0.9 and 2.1 years in 95% of the sample. Significant differences between tooth types were found from intra-individual to inter-regional scales for both dental growth rates and isotopic values. The accuracy of season-of-death assessments differed across the island; those in eastern Tasmania were accurate in all instances whereas those in the west showed substantial inaccuracies. We suggest that this may be due to the elodont form of wombat dentition and the ecologically influenced seasonally varied diet in western Tasmania. As the rate of dental growth is positively correlated with the proportion of coarse vegetation within the diet, this seasonal variation is therefore likely to change how annual isotopic signals are incorporated into the enamel. These results highlight the need to understand the degree of species-specific isotopic variation at a range of scales before applying this technique to archaeological or palaeontological assemblages.

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.

One of the most reliable proofs of terrestrial ice-free conditions within Stadials is the presence of terrestrial vertebrate fauna that require access to vegetation in the winter, for example sedentary birds such as Ptarmigans and herbivorous mammals in particular. The musk ox (Ovibos moschatus) is an example of the latter; modern-day distributions of this species are limited to areas with low snow accumulations. In this paper we discuss the discovery of musk ox bones in Norway. Recently obtained radiocarbon dates on this material demonstrate the presence of this species 41–35 cal kyr B.P. in southern Norway during late Marine Isotope Stage 3 (MIS3). Furthermore the dates have implications for the interpretation of climate and environmental conditions; indicating the existence of a small ice cap in the mountains and climate and vegetation supporting a large mammal fauna in South Norway at that time. publishedVersion

Flexible crinoids (subclass Flexibilia) likely originated from the cladid crinoid genus Cupulocrinus or one of its immediate ancestors in the Middle to Late Ordovician. A remarkably constant and clade-defining character of flexible crinoids is the possession of three plates in the infrabasal circlet of the calyx. This character was a significant morphological modification for the origin of the flexible clade, resulting from the reduction of the number of infrabasal plates from five plates in the ancestral cupulocrinid. Of 615 museum specimens of Cupulocrinus sp. for which the number of infrabasal plates could be determined, 21 specimens, or 3.4%, displayed a deviation from the normal five infrabasals. Of the aberrant specimens, fifteen have four infrabasal plates, and six have six infrabasal plates. An additional aberrant specimen has five infrabasals, with one significantly reduced in size. Although the number of infrabasals is typically thought to be constant within a species, this trait appears to have been variable in the immediate ancestor of flexible crinoids, in the time period just before the number of infrabasals became fixed at three for the Flexibilia. This paper documents the range of aberrations within the infrabasal circlet of Cupulocrinus and considers the implications for the origin of the flexible crinoids.

© 2017. A new Permian-Triassic boundary microbialite (PTBM) is described from the Xiajiacao section of western Hubei Province, South China. The new microbialite, 3.16. m thick, comprises a thin layer of stromatolite and a thick thrombolite unit. An irregular contact separates the uppermost Permian skeletal packstone from the post-extinction stromatolite, but it is not yet possible to discriminate whether it was formed by submarine solution in the wake of ocean acidification or subaerial exposure due to regional regression, or a combination of both. The stromatolite shows "cabbage-like" morphology, and the thrombolite is characterized by centimetric clotted texture. Abundant columns of the microproblematica structure Gakhumella, coccoid-like spheroids, bacterial clump-like spheroids, and hollow spheroids are recognized in both stromatolites and thrombolites and may have played an important role in accretion of the microbialites. Pyrite framboid analysis indicates that microbialites may have been affected by lower dysoxic to upper dysoxic conditions in the immediate aftermath of the Permian-Triassic extinction. Stratigraphic abundance of both high-temperature grains (β-quartz and glassy balls) peaked ~. 20. cm below the biotic extinction horizon, implying that either intensive volcanic eruption occurred only just prior to biotic extinction, or volcanism was still intensive during biotic extinction, but volcanic grains were not deposited in the Xiajiacao locality, likely due to the shallow, agitated environment caused by the regional regression. Overall, microbial bloom, indicated by the widespread PTBMs, seems to have been little affected by the contemporaneous volcanism. We thank both anonymous reviewers and editor Thomas Algeo for critical comments and constructive suggestions, which have greatly improved the quality of the paper. This study is partly supported by the 111 Program of China (B08030), two NSFC grants (41572091, 41402089), and one research grant from the State Key Laboratory of Biogeology and Environmental Geology (BGEG), China University of Geosciences (GBL11206). It is a contribution to the IGCP 630 “Permian–Triassic climatic and environmental extremes and biotic response”.

Immediately after the latest Permian mass extinction, bivalve faunas colonized the Permian-Triassic Transitional Beds (PTTB), especially in littoral clastic facies of South China. The Permian-Triassic (P-Tr) transitional bivalve fauna is composed of holdovers, long-term survivors and newly evolved taxa, and characterized by moderate diversity and high dominance. However, the taxonomy and ecology of this bivalve fauna of littoral clastic facies have not been well understood, especially in comparison with offshore marine records. This paper presents a study on a P-Tr transitional bivalve fauna from five sections of littoral clastic facies in southwestern China, and as such it contributes to a better knowledge of the ecological processes of benthic communities during the P-Tr transition. In total, 20 species in 13 genera of bivalves are identified from the PTTB in the lower part of the Kayitou Formation and the basal part of the Feixianguan Formation of the five sections. Cluster analysis suggests that the transitional bivalve fauna could be further divided into two successive communities (early and late communities), and each is composed of five assemblages. Promyalina–Neoschizodus community (early community) is characterized by presence of holdover taxa, high taxonomic diversity and evenness, and more abundant shallow infaunal suspension feeders. In Pteria community (late community), taxonomic diversity and evenness are much lower, and stationary epifaunal suspension feeders boost at the expense of shallow infaunal suspension feeders compared with the Promyalina–Neoschizodus community. Furthermore, the Promyalina–Neoschizodus community shows a clear spatial variation along environmental gradient from brackish lagoon to shallow marine settings, while the Pteria community is more uniform and homogeneous laterally. The Promyalina–Neoschizodus community in the studied region is of latest Permian age while the Pteria community should belong to the earliest Triassic. Consequently, a significant taxonomical and ecological turnover of bivalve communities occurred between the Promyalina–Neoschizodus community and the Pteria community during the extinction interval in southwestern China.

The Aoerban region of central Inner Mongolia, China is an important early Miocene fossil site that contains a diverse mammalian record unrivaled by other Asian sites of similar age. In this paper, we present lithostratigraphic, biostratigraphic, and magnetostratigraphic data from Aoerban Formation to better understand faunal changes between the Xiejian and Shanwangian Chinese Land Mammal ages. With new biochronological constraints, magnetochrons in the Aoerban Formation can be correlated to C6An.2n to C5Cr with an age range of 20.71–16.72 Ma of the Astronomically Tuned Neogene Timescale (ATNTS2012). The strata of the Aoerban region contain a number of important mammalian First Appearance Data, including several morphotypes of deer (Cervidae), horses (Anchitherium), pika (Alloptox), cricetid rodents (Megacricetodon), and possibly the local earliest record of gomphotheres (i.e., the Proboscidea event). Although the ranges for most of these taxa are still poorly known, some of them, alone or in combination, are useful in defining the base the Shanwangian Land Mammal Age. Within this finely calibrated chronologic framework, the faunas of the Aoerban region are important for better understanding mammalian evolution, biogeography, and paleoenvironment.

The Pannonian Basin of Croatia is the largest back-arc extensional basin on the European continent, located between the Alps, Carpathians and Dinarides. Syn-rift subsidence started at ~18 Ma and predated the onset of the Miocene Climate Optimum (MCO; 17–14.7 Ma). In this paper, we investigate the evolution of the fluvial-lacustrine palaeoenvironment just prior to the transgression of the Central Paratethys Sea. Studies are based on a 17-m-thick section of the Požega palaeolake in the Southern Pannonian Basin using palaeobiological (mollusks, ostracods, palynomorphs, fish otoliths), mineralogical and sedimentological data. Our results reveal fluctuating freshwater and brackish conditions and a pulsating water budget, which we relate to phases in which the basin was, alternatively, hydrologically open and closed. We infer that the alternating environmental conditions can be best-explained by dry and wet periods, respectively. Droughts produced stagnant conditions, algae overproduction and increased salinity levels, supporting the survival of sporadically invading brackish water species. The wet periods, on the other hand, led to lake highstand episodes, expansion of lake area, and to the widespread development of profundal facies. The lake basin eventually became overfilled and connected through outflowing rivers with the Central Paratethys sea. However, the absence of brackish-marine assemblages in the Požega palaeolake nevertheless indicates that there was no marine water inflow from the Central Paratethys at that time.

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.

Oligocene paleoceanographic changes are useful for assessing future changes in the warming world because the levels of atmospheric pCO2 in the Oligocene were similar to those expected within the next century. However, the overall Oligocene history is still unclear even though our understanding has been improved by previous studies. In this paper, we review the preexisting hypotheses for the Eocene–Oligocene and Oligocene–Miocene changes as well as the long-term global changes. Based on newly compiled Cibicidoides spp. δ18O (δ18OCIB) records, we divide the Oligocene paleoceanographic changes into five phases: an abrupt increase in δ18OCIB values during the Eocene–Oligocene transition (EOT) (Phase 1), a gradual decrease in the early Oligocene (Phase 2), a long-term slow increase in the early to middle Oligocene (Phase 3), a gradual decrease in the late Oligocene (Phase 4) and an abrupt increase near the Oligocene–Miocene transition (OMT) (Phase 5). These recurring sequential changes in the global-scale δ18OCIB profile following the EOT are likely not directly connected to the strengthening and stratification of ocean currents during the Oligocene as a result of the unidirectional strengthening of the Antarctic circumpolar current (ACC) and the northern component water (NCW). Instead, we suggest that the strengthened ocean currents contributed significantly to interbasinal differences in δ18OCIB values. For a more robust explanation of Oligocene long-term δ18OCIB changes following the EOT, future studies will require high-resolution and more reproducible records of changes in the volume of Antarctic ice and atmospheric pCO2, as well as information about the tectonic history.

The relationship between ungulate stable carbon isotope values and environmental variables (temperature, relative humidity, precipitation) remains poorly understood. In this paper, we evaluate this relationship for, predominantly, C3 ecosystems in the winter rainfall areas of southern Africa. In our dataset (290 individuals representing 23 species), δ13C values of ungulate enamel are significantly correlated with mean annual precipitation (MAP), moisture index (MI) and summer aridity index (SAI), variables that also influence the distribution of C3/C4 grasses. Our study confirms previous findings that faunal δ13C values in C3 ecosystems are most strongly correlated with variables related to precipitation. δ13Cenamel values for ungulate browsers are more strongly correlated with a larger number of environmental variables than values for grazers and mixed feeders and vary according to vegetation type. We apply regressions derived from the modern dataset to estimate palaeoclimatic shifts based on δ13Cenamel values of browsing fauna at the Pleistocene sites of Hoedjiespunt and Elandsfontein in South Africa.

Although clypeasteroid echinoids are very common in the shallow water sediments of the Miocene of Sardinia, they have received little attention as far as their origin is concerned. In this paper, three sand dollar dominated mass accumulations from the Lower Miocene of Sardinia are studied and compared in order to understand their genesis and palaeoecology. Two clypeasteroid assemblages were found in the Sarcidano region (Central Sardinia) within the Nurallao Formation (Late Oligocene–Burdigalian). The third sand dollar mass occurrence crops out in the Logudoro region (northern Sardinia) within the Calcari di Mores Formation (Late Burdigalian). These fossil echinoid deposits show a low taxonomic diversity; two assemblages are dominated by the genus Amphiope while the other is dominated by Parascutella with subordinate Clypeaster. An integrated stratigraphic, taphonomic and sedimentological approach allows different genetic mechanisms for these shallow water, sandy, shoreface deposits to be inferred. The origin of these deposits is related to ecological, morphological and sedimentological factors. The sand dollars of Cuccuru Tuvullao (Nuragus) show high degrees of abrasion and fragmentation and represent a multiple in situ reworked accumulation while the assemblage of Duidduru (Genoni), with low abrasion and variously oriented complete and fragmented specimens constitutes an example of a proximal storm deposits. The sand dollar bed of Monte Sa Loca (Chiaramonti) consists of a dense accumulation of well-preserved, mainly concordant-oriented, juvenile and adult specimens and is considered to represent an autochthonous assemblage. This paper explores the role of detailed sedimentological and taphonomic analysis in the palaeoecological and genetic interpretations of the sand dollar beds and points out the widespread distribution and diversification of these echinoids in the Miocene deposits of the Mediterranean area.

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 Eocene was an interval of climate evolution, when the extreme high temperatures of the earliest Cenozoic gave way to a global cooling trend. Fine-grained lacustrine sediments of Eocene age from northeastern China represent an excellent archive to study long-term environmental and climatic changes at high-resolution. The Huadian Basin is a Cenozoic, fault-bounded basin in Jilin Province, northeastern China. Though small in area, it contains numerous oil shale- and coal-bearing layers, which provide an abundant Middle to Late Eocene palynoflora. Eighty-five palynomorph genera and one hundred palynomorph species were identified in the Huadian Formation, allowing to distinguish 4 palynozones. The nearest living relatives of the recovered palynomorph taxa suggest the presence of subtropical evergreen and deciduous broad-leaved forests during deposition of the Huadian Formation. Using the coexistence approach (CA), we calculated seven paleoclimatic parameters, which indicate a subtropical warm and humid climate with a mean annual temperature above 13.6 °C and a mean annual precipitation of at least 887 mm. However, the climate became cooler and drier during the transition from the lower Oil Shale Member to the upper Carbonaceous Shale Member. Palaeoclimatic data from the various Middle and Late Eocene basins of northeastern China (i.e., the Huadian, Fushun, Yilan, Hunchun and Jishu basins) were compared with data from North American and European basins. Middle Eocene climate in the Northern Hemisphere was generally warm and humid, and the mean annual temperature and precipitation in northeastern China were similar to those in North America, though slightly lower than those of Europe. Similar trends in temperature and precipitation on different continents support the existence of a global Mid-Eocene cooling event. This paper is the first systematic study of Middle to Late Eocene seasonality in the Huadian Basin. Our results show an apparent differentiation in both temperature and precipitation between summer and winter, supporting the view that the East Asian Monsoon was established in northeastern China already during the Middle to Late Eocene. This Middle and Late Eocene monsoon was likely driven by the development of Pacific trade winds and an alternating, seasonal high- and low-pressure system over Siberia. The climatic changes observed in our dataset, especially the precipitation changes, appear to have played an important role in controlling oil shale formation in the Huadian Basin. A warmer and more humid climate, with abundant precipitation and high subsidence rates, formed a deeper Huadian depositional lake. High productivity and stable stratification provided the abundant organic matter and favorable preservation conditions necessary for oil shale accumulation.

This special issue provides new studies in the field of Cenozoic climate change in eastern Asia. The papers in this volume are multidisciplinary in nature and examine a range of topics including paleovegetation, sedimentology, clay mineralogy, geochemistry, magnetostratigraphy, and climate modelling. The findings of these studies demonstrate that analysis of terrestrial paleoclimate changes in eastern Asia may offer insights into the effects of Tibetan Plateau uplift, and ultimately the dynamic processes of global change that took hold throughout the Cenozoic. The second part of this special issue, to be published later, will add a paleoecology component, examining how Cenozoic climate change has impacted floras and faunas in eastern Asia.

The destruction and damage of fossils in palaeontological collections through pyrite (FeS2) oxidation is a major and well-known issue. In this paper, we investigate the impact of this reaction on the conservation of Xiaheyan fossil entomofauna (Tupo Formation; Late Carboniferous; Ningxia, China) through three steps. First, we examined and characterised the elemental and mineralogical composition of newly excavated specimens, of museum specimens, and of weathering products at the outcrop (using SEM-EDX, Raman microspectroscopy and XRD). Second, in order to determine the potential reactivity of newly excavated fossils, we performed artificial ageing experiments, a technique recently applied in palaeontology that can offer valuable insights into long-term conservation of fossils. Finally, we designed and applied a protocol aiming at forcing the formation of gypsum outside the fossils so as to preserve the fossil integrity, namely ‘crystallisation pits’. Our data demonstrate that the depositional environment at Xiaheyan was rich in sulphur and devoid of oxygen, with perhaps oxygen-rich microenvironments, which led, respectively, to the precipitation of framboidal pyrite and of primary iron oxyhydroxides. The further chemical palaeo-weathering led to an extensive oxidation of pyrite in the outcrop, resulting in the precipitation of secondary iron oxyhydroxides, and of jarosite and gypsum, both sulphates. The low abundance of iron oxyhydroxides and the poor diversity of sulphates, compared to analogous localities, indicate a distinct weathering scenario, with a persistence of acidic water and an extensive leaching leading to the maintenance of only insoluble sulphates. Despite the extensive in situ pyrite oxidation, artificial ageing experiments demonstrated a remaining weak degradation potential. Gypsum (a calcium sulphate) is the near-exclusive efflorescence to develop within artificially aged fossils, contrary to the most commonly encountered efflorescence on pyritised fossils, namely iron sulphate. This instance can be attributed to the complete mobilisation of iron through iron oxyhydroxide precipitation and the availability of calcium ions induced by the dissolution of calcium carbonates present on Xiaheyan outcrops during palaeo-weathering. Unfortunately, the recourse to crystallisation pits failed to prompt gypsum crystallisation. We further suggest preventive storage conditions and prospects for investigation on the gypsum precipitation process at work, notably the role of organic compounds.

International audience; Environmental changes related to forest expansion and later to agricultural development and deforestation during the Holocene in Europe have strongly shaped herbivore distribution and habitat selection, leading to species extinction. In this paper, we examine, through dental microwear textural analysis, the foraging habitats, dietary flexibility and niche partitioning of large herbivores (100 to 1000 kg) including two bovids (European bison Bison bonasus and aurochs Bos primigenius) and two cervids (moose Alces alces and red deer Cervus elaphus). The study focuses on northeast (NE) and south central (SC) Europe during three periods of the Holocene: Neolithic (6500–3500 cal yrs BP), Roman Period and Middle Ages (~2000–450 cal yrs BP) and Recent times (1963–2014). Our study highlights differences in diet between species only in the Neolithic SC Europe. This may have resulted from diversified habitats and dietary niche separation in SC Europe. The absence of differences in NE Europe may suggest more homogeneous habitat conditions in combination with lower densities of large herbivores in forested habitats. Analysis shows that during the Neolithic, in the bison diet there was more herbaceous monocotyledons in SC Europe than in NE Europe. We also found temporal changes in microwear texture variables for the bison in SC Europe suggesting a more herbaceous diet in the Neolithic than during the Roman Period and Middle Ages. However, neither spatial nor temporal differences in microwear texture variables were found in the aurochs. Thus, the diet of the European bison has likely changed, which may indicate a greater plasticity that promoted survival in refuge habitats.