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In this paper, we critically review the half-century (1962–2022) history of study of Oligocene to Pliocene mammal-bearing successions in the eastern Linxia Basin, Gansu Province, China. Despite great strides in our understanding of the regional geology and the discovery of a large quantity of mammal fossils, there remains major discrepancies concerning the definition and age assignment of the formations that comprise the Linxia Group. This has resulted in the development of two competing schemes for its subdivision: the first scheme was proposed by geologists of the Lanzhou University and the Institute of Tibetan Plateau Research, and the second scheme is associated with paleontologists of the Institute of Vertebrate Paleontology and Paleoanthropology. In an attempt to solve these discrepancies, a five year project was initiated in 2017, and herein we report the main findings as follows: (1) The Jiaozigou Formation does not extend into the Miocene, with its top calibrated at about 23 Ma; (2) The Liushu Formation, as defined in the Maogou section, should be considered as the penecontemporaneous shallow water facies of the coarse-grained Hujialiang Formation of Middle Miocene age; (3) The widespread Hipparion -bearing deposits along the Guangtong River, which have been also referred to the "Liushu" Formation represent a different stratigraphic unit and should be given another name to eliminate confusion following further stratigraphic analysis. • A brief, but comprehensive review of the studied history of the Linxia Basin. • We pointed out ambiguous opinions and misunderstandings in previous studies. • A reliable chronology of precise sedimentary sequences was established with constraints of accurate mammal fossils. [ABSTRACT FROM AUTHOR]

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. • Nihewan in north China is a key area for research on the early human occupation out of Africa. • Madigou (MDG) is a newly discovered Early Pleistocene site complex in the Nihewan Basin. • Magnetostratigraphic results show that early humans occupied the MDG site ca. 1.2 Ma. • MDG hominins lived in an open habitat and practiced a core and flake technology. • Human adaptations correlate with climate variability during the onset of the Mid-Pleistocene transition (MPT). [ABSTRACT FROM AUTHOR]

Abstract This special issue of Palaeogeography Palaeoclimatology Palaeoecology on "Cenozoic Climate Change in Eastern Asia" contains a series of multidisciplinary studies representing a wide range of research on paleovegetation, sedimentology, clay mineralogy, geochemistry, magnetostratigraphy, and climate modelling. The general significance of these studies is 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 present volume is Part II of this special issue. The first part of the special issue was dedicated to understanding eastern Asian paleoclimate variation during the Cenozoic by especially evaluating proxy data from geochemistry and climate modeling. Part II includes additional geochemical studies of terrestrial deposits from different regions of eastern Asia as well as climate modeling. Some of these papers focus on the impact or effect of these climatic changes on various floras and faunas in this region. In these studies, the period investigated ranges from the Eocene to the middle Holocene, thus encompassing most of the Cenozoic. Collectively, these studies provide significant new insights into the Cenozoic paleoclimate framework of eastern Asia. [ABSTRACT FROM AUTHOR]

The destruction and damage of fossils in palaeontological collections through pyrite (FeS 2 ) 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. [ABSTRACT FROM AUTHOR]

Abstract: The relative importance of tectonism and sea-level change in driving Middle to Late Devonian biogeographic patterns in marine invertebrates is investigated using phylogenetic biogeography. Taxa considered include two clades of brachiopods, one bivalve clade, and a suborder of phyllocarid crustaceans. These organisms colonized different depositional environments and played different roles in the Devonian ecosystem which allows biogeographic patterns to be considered in a cross-faunal analysis. Vicariance patterns are well resolved and may reflect biogeographic relationships developed in the Early to early Middle Devonian due to the uplift of intracratonic arches. Uplift of tectonic arches is inferred to occur during times of tectonic quiescence during the second and third (and possibly also the first) tectophase (after Ettensohn, F.R., 1985. The Catskill Delta complex and the Acadian Orogeny: a model. In: Woodrow, D. L., Sevon, W. D. (Eds.), The Catskill Delta. Geological Society of America, Boulder, CO, Special Paper 201, pp. 39–49.) of the Acadian orogeny. Geo-dispersal patterns are not as well resolved, but may indicate dispersal across tectonic arches during downwarping associated with increased compressional tectonism during Ettensohn''s (1985) [Ettensohn, F.R., 1985. The Catskill Delta complex and the Acadian Orogeny: a model. In: Woodrow, D. L., Sevon, W. D. (Eds.), The Catskill Delta. Geological Society of America, Boulder, CO, Special Paper 201, pp. 39–49] tectophases II and III. Geo-dispersal across relatively low arches may also be coincident with transgressive events IIa and IIc of Johnson et al. (1985) [Johnson, J.G., Klapper, G., Sandberg, C.A., 1985. Devonian eustatic fluctuations in Euramerica. Geological Society of America Bulletin 96, 567–587]. The overall lack of congruence between the vicariance and geo-dispersal patterns suggests that singular, tectonic events exerted more profound influence on Devonian biogeography than cyclical changes in sea level. Furthermore, the offset in perceived timing between vicariance and geo-dispersal patterns may indicate a fundamental change in the style of biogeographic patterns during the Middle Devonian and may have played a major factor in regulating biodiversity dynamics during the Late Devonian biodiversity crisis. [Copyright &y& Elsevier]

Cenozoic faunal exchanges between Europe, Asia, Africa and America played a key role in shaping modern-day Eurasian ecosystems with dispersal pathways controlled by the dynamics of natural palaeogeographic barriers (e.g., deserts, isthmuses, large water bodies, etc.). The South Caucasus is a mountainous region between Asia and Europe, which served as an important dispersal route during the late Cenozoic for the intercontinental exchanges of diverse terrestrial vertebrates. The Pliocene geology of this region is dominated by volcanic and volcaniclastic deposits that are generally not favourable for fossil preservation. However, a few rich fossil vertebrate faunas do occur although they lack comprehensive palaeoenvironmental and age constraints. In this paper, we present an integrated study of the stratigraphy and palaeontology of the Jradzor section located in the Gegham volcanic province of Armenia, to improve knowledge of late Cenozoic dispersal pathways. The 57-m-thick succession comprises 19 fossiliferous horizons with at least 48 identified vertebrate taxa (excluding birds). The palaeoenvironmental reconstruction suggests that the succession was deposited within a short-lived dammed lake that was subject to pyroclastic density flows, and later evolved into soil catenas. Taphonomic observations indicate that pyroclastic flows caused a high mortality of small-size vertebrates in most fossiliferous horizons, while a catastrophic lahar buried the large vertebrate fauna. Multiproxy dating places the studied section between 4.3 and ∼ 3.03 Ma and the mammalian fauna correlates to the MN15. Comparison with similar age localities from across the region shows that Jradzor comprises the most continuous Pliocene succession with the highest number of fossil taxa and fills the MN15 interregional gap. The rich fossil vertebrate faunas have Asian and primarily European affinities. Findings show that the South Caucasus was a significant dispersal route for terrestrial vertebrates between Europe, Asia and Africa, and is of crucial importance for understanding Eurasian palaeogeography. • A new vertebrate fauna with >49 taxa from the Pliocene volcanic terrain of the South Caucasus. • The Jradzor fossil record dated between 4.3 and 3.1 Ma fills the MN15 interregional gap. • High mortality on site was mainly caused by pyroclastic density currents and lahars. • MN15 zone of the South Caucasus mammalian record has Asian and predominantly European affinities. • The South Caucasus is a key palaeobiogeographic tying point between Europe, Asia and Africa. [ABSTRACT FROM AUTHOR]

In this paper, we synthesize sedimentological, magnetostratigraphic and paleontological data from the continental vertebrate site of Puerto de la Cadena (Murcia, SE Spain), in order to clarify its age. The study site is located on the northern edge of the Carrascoy mountain range, in the upper part of the Cigarrón Unit. The end-Messinian discontinuity has been detected at the base of this unit, which indicates it has an early Pliocene age. Abundant remains of small and large vertebrates, including rodents, lagomorphs, primates, carnivorans, perissodactyls, artiodactyls, proboscideans, testudines, squamats, and crocodiles, have been found in this area. Some of these elements are of African origin, such as Debruijnimys sp., Macaca sp., and Sivatherium cf. hendeyi , and their presence is related to the Messinian Salinity Crisis. In addition, remains found at this site verify the persistence of Crocodylia in the European record beyond the late Miocene. The association includes typical elements of the early Ruscinian terrestrial record (MN14), like Apocricetus cf. barrierei , Sivatherium , Gazella aff. baturra , and Hipparion fissurae . The Puerto de la Cadena site is located in a reversed geomagnetic chron that has been correlated with C3n.3r (from 4.997 to 4.896 Ma). According to this correlation, the MN13/MN14 boundary has a minimum age of 4.9 Ma. [ABSTRACT FROM AUTHOR]

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 2 nd -, 3 rd -, and 4 th -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 4 th -order sequences supports suggestions of glacio-eustatic sea-level changes in the Jurassic. [ABSTRACT FROM AUTHOR]

Two new 40 Ar/ 39 Ar ages (*) and previously published K/Ar ages of basaltic pillow lava flows are coeval with closely-related fossiliferous marine layers, allowing us to establish the beginning (5.8; 5.0; 4.8 Ma at Ajuí, Fuerteventura Island and 4.8 ± 0.03 Ma (2σ)* at Tamaraceite) and a middle stage (4.20 ± 0.18 Ma (2σ)* at La Esfinge in Gran Canaria Island) of Early Pliocene marine deposits in the Canary Islands. Here the presence of tropicopolitan fossils ( Megaselachus megalodon, Janthina typica ) suggests the influence of a possible Central American Circumtropical Current during the Pliocene and in the North Atlantic basin. The presence of both Janthina typica and the Argonauta argo also indicate the occurrence of tropical storms in the area of the Canary Islands around that time. In addition, the pillow lava flow at La Esfinge overlies a submarine pyroclastic layer containing Ostrea offreti that was preserved in its life position, a fossil from the terminal Miocene and commonly found on the south eastern Iberian Peninsula. At La Cruz on Fuerteventura Island, a dune formed above marine deposits lies beneath a palaeosol and a basaltic lava flow that was K/Ar dated at 2.9 Ma. Near El Mármol in Gran Canaria the corresponding palaeosol lies between lava flows K/Ar dated at 3 Ma. Based on these observations, we argue in this paper that the first appearance of the Canary Current, the eastern boundary current of the North Atlantic sub-tropical gyre, occurred between 4.2 Ma and 2.9 Ma ago. This was followed by a major sea level drop (of about 40 m) and the formation of a first fossil-bearing palaeosol which indicate that major climate change that took place around 2.95–2.82 Ma. [ABSTRACT FROM AUTHOR]

The Qinghai-Tibet Plateau (QTP) contains rock successions that record the detailed history of the evolution of the Tethyan oceans. The purpose of this Special Issue is to improve understanding of the complex evolution of the blocks/terranes and oceans in the QTP. It comprises 21 papers covering diverse disciplines including stratigraphy, palaeontology, geochemistry, paleomagnetics and sedimentology. Some of the major findings of the collection are as follows: (1) There exist many branches of the Prototethys Ocean in the QTP with complex history of evolution and subduction; (2) The Paleotethys Ocean along the Longmu Co-Shuanghu suture zone began to widen in Early Carboniferous times; (3) The Mesotethys Ocean opened during Early Permian times as indicated by both paleobiogeographic and provenance studies; (4) There are more than two forearc basins developed during the subduction of the Neotethys Ocean. The various contributions in this Special Issue provide detailed evidence to reconstruct the complicated evolution of the Tethyan oceans involved in the formation of the QTP. The articles will be of interests to scholars across many disciplines in the geosciences. [ABSTRACT FROM AUTHOR]

Abstract: Attaichnus kuenzelii is a nest of leaf-cutting ants from the Miocene of La Pampa, Argentina, described by Laza (1982) in a pioneer paper for insect palaeoichnology. The type locality was revisited to update morphological description, affinities, and palaeoenvironmental conditions. In present day outcrops, A. kuenzelii shows no mounds or high concentration of interconnected chambers as originally described, but well separated and regularly distributed chambers, which at most may compose groups of two or three. This updated morphology suggests that A. kuenzelii can be attributed to Attini other than Atta, probably species of Acromyrmex or Trachymyrmex. Associated trace fossils are large vertebrate burrows, rhizoliths, meniscate burrows, and scarce Coprinisphaera. Other specimens of dung beetle and bee trace fossils found in the same palaeosols were probably constructed by younger producers on soils developed on post-Miocene sediments, which are mostly eroded today. Evidence for this assumption is the lack of carbonate cementation and presence of organic remains in these traces. The reinterpretation of A. kuenzelii as a nest of species of Acromyrmex or Trachymyrmex modifies the original assumption of a northern subtropical palaeoenvironment during the Miocene for this area based on the distribution of Atta species. The new affinities proposed in combination with the studied palaeosols interpreted as mollisols, phytoliths, and previous palaeontological, and sedimentological evidence suggest an open palaeoenvironment under a temperate climate, dominated by grasses. [Copyright &y& Elsevier]

Abstract: Songliao Basin in NE China developed the most productive oilfield in the world sourced from terrestrial rocks. The main source rock of the basin includes member 1 of the Qingshankou (K2qn1) and members 1 and 2 of the Nenjiang Formation (K2nj1–2). However the exact reasons for the formation of the source rock, especially the K2qn1 are still controversial. Former paleontological and organic geochemical research suggested that organic matter was deposited during marine incursion events of K2qn1 but further geochemical evidence is needed. This paper explores the distinct sulfate levels that distinguish marine from fresh waters of the Songliao paleo-lake. We undertook a systematic investigation the sulfur geochemistry of the sediments from top of member 4 of the Quantou Formation (K1q4) to top of member 1 of the Qingshankou (K2qn1). The ratio of organic carbon to the pyrite sulfur (TOC/PYS) proved the previously suggested saline conditions during the deposition of K2qn1; and the pyrite sulfur isotope indicated that marine incursion may not only have occurred for K2qn1, but also for top of K1q4. The exact time for the beginning of marine incursion is to be determined. The marine incursion within K2qn1 is not strong and partially controlled by the fluctuation of paleo-lake level. The present study will be helpful for understanding the contribution of marine incursion events to the burial of organic carbon in the Songliao paleo-lake, although further studies are still needed. [Copyright &y& Elsevier]

Abstract: This paper presents an overview on some significant historical sources, particularly from 17th to 18th century Italian scientific literature, in order to understand how color was used as one of the ‘external’ features for identifying rock formations, also including fossils, regarded as having formed in different times by different causes or events. The reference to color was also considered the main feature used for lithostratigraphical purposes within the so called ‘classifications’ of mountains in the second half of the 18th century. Later geologists and mineralogists involved in the early development of stratigraphy referred to color when a rock formation or specimen appeared to be less distinguishable by other main characters (for example chemical and morphological features). [Copyright &y& Elsevier]

Abstract: The paper presents the first paleontological data (pollen, plant macrofossil, diatom and ostracod) on the sediments of Lake Beloye, which is situated in the forest-steppe zone of Western Siberia. Our study contributes to better understanding of the Middle–Late Holocene regional to local environmental changes. Regionally, we recognized a cold stage of 3.4–2.3 calibrated ka BP and a dry stage of 2.8–1.7ka BP. The dry stage coincides with the climate-driven lowered level of the lake at 2.6–1.5ka BP. Later, the climate changed to warmer and wetter, which resulted in a highest stand of the lake at 1.3–0.2ka BP and was followed by the lowering of the lake. Forest-steppe persisted in this area during the whole period under consideration, but probably shifted southward. Such a shift is reflected in the environment around Lake Beloye similar to that of modern taiga, which existed at 3.2–1.3ka BP, however, compared to the colder and wetter climate of taiga, the conditions were colder and drier. The local plant associations and the lake ecosystem were affected by those events of climate and lake level changes. The initial eutrophic sedge-reed swamp evolved to the oligo-mesotrophic sphagnum bog, which existed around the lake at 3.2–1.3ka BP. Later, the bogging process was interrupted by the lake transgression, after which the dried bog around the lake was occupied by the birch forest. The lake ecosystem was strongly affected by the 3.4ka BP climate change: the low-alkaline eutrophic lake with abundant water higher plants and diatoms changed to the alkaline oligotrophic lake with calcium-fixing macrophytic algae and angiosperms. This resulted in total change of lake''s bio-geochemical and sedimentation patterns. [Copyright &y& Elsevier]

Abstract: The Upper Triassic sediments both in NW Europe and in the Mediterranean region imply a generally arid climate regime. In the Carnian, however, a humid phase with a high input of siliciclastics is assumed (‘Carnian Pluvial Event’) but its causes are still highly controversial. The Carnian marine succession of the Transdanubian Range (TR), Hungary also shows a significant change in sedimentation: pelagic carbonate deposition (Füred Limestone Formation) was followed by the formation of marly sediments (Veszprém Marl and Sándorhegy Formations). In order to understand the environmental changes, the clay mineralogy of 240 Carnian samples determined by X-ray diffraction is discussed in the present paper. Additionally, this set of clay mineral data from four boreholes from the Bakony Hills (Bakonyszűcs Bszü–1), Balaton Highland (Balatonfüred Bfü–1, Mencshely Met–1) and Zsámbék Basin (Zsámbék Zs–14) allows us to test the reliability of clay minerals as palaeoclimatic proxies for the Carnian (Late Triassic) by reconstructing spatial and temporal variations. The first increase in clay content of the studied Carnian succession can be detected in the limestone/marl couplets of the‘Cordevolian’ Füred Limestone. Its clay fraction is dominated by illite, mixed-layer illite/smectite (IS) and chlorite without kaolinite, a good indicator of landmasses with a hot climate and constant humidity, thus this compositional change probably related to a sea-level drop. Subsequently, the clay mineral assemblages of the Veszprém Marl sections in the Bakony Hills and the Balaton Highland are composed of illite, poorly ordered (R=0) IS with 60–70% expandable component, chlorite and kaolinite. On the other hand, the clay fraction of the samples from the Zsámbék Basin is composed of illite, IS with an average of 40–50% expandable component and a transitional R=0 to R=1 type of ordering and kaolinite; chlorite does not occur. In the Early Julian, kaolinite enrichments (~10–20%) in the clay fraction can be regarded as a manifestation of the climate shift from the prevailing aridity to the more seasonal climate with enhanced humid season. The overall presence of abundant illite and accompanying chlorite can indicate a high rate of erosion of moderately weathered rocks, while the large amount of smectitic clay (transformed to IS) could be partly derived from transport of weathering products from a distant source area and, subordinately, from diagenetic alteration of intermediate to basic volcanic rocks. Spatial variation in the expandability and ordering of the IS, at least partially, could be caused by different degree of the diagenetic overprint. [Copyright &y& Elsevier]

Abstract: The paper considers the biogeography and palaeogeographic implications of the Permian marine bivalve faunas of Northeast Asia, with a focus on the dynamic relationships between biotic similarities and palaeogeographic distance through an interval of ca. 50million years. A stage-by-stage time series analysis of the biotic similarities between two previously recognized biochores in Northeast Asia, the Kolyma–Omolon and Verkhoyan–Okhotsk provinces, has been carried out using both the Jaccard and Dice similarity indices based on the spatio-temporal distributions of 355 Permian marine bivalve species in Northeast Asia. The outcome of this analysis, combined with other empirical data and previously published tectonic, sedimentological and palaeontological information, suggests that (1) the bivalve faunas from these two provinces were distinctive from one another as two separate biochores throughout all but the earliest (Asselian) Permian stages and (2) the biotic similarities between the Verkhoyan–Okhotsk and Kolyma–Omolon provinces remained consistently low since Sakmarian, all falling well below the minimum threshold of the Jaccard index of 0.42 required for distinguishing marine biotic provinces. We interpret these below-threshold Jaccard biotic similarities as an indication of significant palaeogeographic separation between the Verkhoyan-Okhotsk and Kolyma–Omolon provinces, which is in turn considered to indicate rifting and sea-floor spreading of the Omolon microcontinent and associated terranes and island arcs away from the North Asian craton, at least from the Sakmarian to the beginning of the Late Permian. Palaeo-distance separation appears to be the primary and most significant biogeographic determinant in accounting for the differences in the spatial distribution of most Permian bivalve species in Northeast Asia. Several other variables also appear to have played a significant role, including regional climate conditions, ocean currents and merged island chains as geographic barriers. In particular, the relatively high biotic similarity between the Verkhoyan–Okhotsk and Kolyma–Omolon provinces during the Late Wuchiapingian and Changhsingian may have been related to the shallowing of the deep-water basins (Oimyakon, Ayan-Yuryakh, Balygychan and Sugoi basins) that had previously separated the two provinces and the flooding (submergence) of the Okhotsk–Taigonos volcanic arc system, thus allowing the invasion of lower latitude warm-water Palaeotethyan and even Gondwanan species into Northeast Asia. [Copyright &y& Elsevier]

Abstract: This paper presents a high-resolution micropalaeontological study, integrated with geochemical and sedimentological analyses of the Triassic–Jurassic (Tr–J) transition at the Doniford section (SW England). Our analyses indicate the renewal of surface carbonate production in the Blue Lias Formation (early Hettangian) after the end-Triassic mass extinction. Based on the high abundance of surface carbonate producers (schizosphaerellids), which occurred in phase with development at sea-floor of calcareous hyaline benthic foraminifers, we deduce that a benthic–pelagic coupling resulted in both the initial restoration of the biological carbonate pump, and also a more efficient export production. The presence of monospecific phytoplankton assemblages and benthic foraminiferal assemblages typical of poorly oxygenated environments suggest that the environmental stress continued after the end-Triassic maximal perturbation. Complete environmental recovery was prevented by a succession of alternating dysaerobic and anoxic phases that favoured the deposition of black-shale sediments. The hypothesis of a methane-release mechanism as a trigger for the global carbon cycle perturbation and greenhouse conditions during the early Jurassic is discounted, based on evidence from the decoupled carbon isotope records of carbonate and organic matter. Apart from local control of a high amplitude sea-level change across the Tr–J boundary, the succession and nature of events at Doniford are consistent with a scenario of global environmental and biotic changes triggered by the physical and chemical effects of the Central Atlantic Magmatic Province (CAMP) volcanism. A super greenhouse climate in the aftermath of the end-Triassic mass extinction appears to be the results of the combination of the long-term CO2 accumulation in the atmosphere system due to the CAMP volcanic activity, as well as the inefficiency of the biological pump due to reduced export production. [Copyright &y& Elsevier]

Abstract: The ‘Great Ordovician Biodiversification Event’ (GOBE) saw a spectacular increase in marine biodiversity at all taxonomic levels largely within the phyla established much earlier during the so-called ‘Cambrian Explosion’. The diversification was probably the result of a combination of several geological and biological processes and the positive feedbacks resulting from them. The present paper reviews the palaeoecological dimension of the GOBE. It involved major increases in α, ß and γ biodiversity largely associated with the rise of the Paleozoic Evolutionary Fauna dominated by suspension feeders and involving a greater occupation of ecospace and more complex ecological structures in the Ecological Evolutionary Units P1 and P2. In the benthos, these include more complex food webs than those of the Cambrian, greater tiering, especially above the sediment–water interface, and the development of guild structures indicating increased competition between taxa for particular resources. The Ordovician is characterized by a profound change in reef composition, with a switch from microbial-dominated reefs in the Early and Middle Ordovician to metazoan-dominated reefs in the Late Ordovician. Increases in complexity of deep-water trace fossil assemblages began in the Early Ordovician and mark the increasing exploitation in that environment and the development of hardgrounds permitted bioerosion and encrusting strategies together with the appearance of cryptic communities. Within the water column, the GOBE involved a significant increase in the diversity of the phytoplankton and the development of a diverse zooplankton (including planktotrophic larvae from a range of invertebrate clades). This revolution in the plankton enabled the establishment of a diverse fauna of pelagic vertebrates, molluscs and arthropods and promoted the rise of suspension feeders in the benthos. An escalation amongst predators and thus community evolution may also have been a major driver of biodiversification. [Copyright &y& Elsevier]

Abstract: Research on the uppermost Cretaceous continental deposits with dinosaur remains from the Haţeg Basin has behind it a history of more than 110years. The first studies were by Franz Nopcsa (1877–1933) who published between 1897 and 1929 a series of notes and papers on this fauna, including five monographs dedicated to the Haţeg dinosaurs. Nopcsa described 10 vertebrate taxa, including dinosaurs, crocodilians and turtles, from the Haţeg Basin, out of which 6 are still valid. He recognized the primitiveness and the small size of most of the taxa from the Haţeg palaeofauna, characters that he related to the isolated island environment within which this fauna lived for a long time span. After Nopcsa, systematic research on the Haţeg fauna was interrupted for many decades, being resumed after 1977 when D. Grigorescu, leading a small group of students in Geology started to explore the deposits outcropping along the Sibişel valley, near Sânpetru village, from where Nopcsa made most of his collection of fossil bones. Since then the fieldwork continued every summer until now, numerous remains of dinosaurs, crocodiles and turtles being unearthed. The list of the Maastrichtian fauna from Haţeg currently includes 56 taxa from all vertebrate classes. More than half of the recorded taxa were discovered in micropalaeontological samples through screen-washing. The most spectacular discoveries made after 1977 include a large variety of small theropods, several sites with dinosaur egg clutches, one of these also yielding hatchling remains, one of the largest pterosaurs in the world, representing a new genus and species, Hatzegopteryx thambema, and several taxa of multituberculate mammals. Studies of the Haţeg fauna were not restricted to systematic palaeontology, but also covered all the fields that contribute together to an accurate reconstruction of the environment within which the Maastrichtian fauna existed. This overview includes a list of contributors to the actual knowledge on the Haţeg fauna, during the last 30years, divided by fields of scientific interest. [Copyright &y& Elsevier]

Abstract: This paper describes recent material gathered during the second fieldwork at Ma U''Oi in November 2002 by a Vietnamese–French–Japanese team. The Ma U''Oi cave, located in the province of Hoà Binh (60 km SW from Hanoi), northern Vietnam, belongs to a karstic network developed in Triassic dark-grey limestones. The cave is filled with coarse-grained breccias containing numerous fossil remains, partially preserved at several loci inside the cave (wall, vault and ground). We describe new teeth which confirm the occurrence of mammal taxa already mentioned at Ma U''Oi (Bacon et al., 2004)[Bacon, A-M., Demeter, F., Schuster, M., Long, V.T., Thuy, N.K., Antoine, P-O., Sen, S., Nga, H.H., Huong, N.T.M., 2004. The Pleistocene Ma U''Oi cave, northern Vietnam: palaeontology, sedimentology and palaeoenvironments. Geobios 37, 305–314], while others, mainly microvertebrates, emphasize the occurrence of new species for the Pleistocene of Vietnam. We report here, for the first time, the occurrence of these microvertebrates of different groups (primates, rodents, insectivores, small reptiles and amphibians) in the faunal assemblage. Among mammal taxa, the presence of one more hominid affiliated to archaic Homo is also attested by our findings. U/Th dating carried out on 2 samples extracted from breccia speleothems confirms the biochronological estimate, with fossiliferous fillings ranging from late Middle Pleistocene to Late Pleistocene. [Copyright &y& Elsevier]

Abstract: During deglaciation of the North American Laurentide Ice Sheet large proglacial lakes developed in positions where proglacial drainage was impeded by the ice margin. For some of these lakes, it is known that subsequent drainage had an abrupt and widespread impact on North Atlantic Ocean circulation and climate, but less is known about the impact that the lakes exerted on ice sheet dynamics. This paper reports palaeogeographic reconstructions of the evolution of proglacial lakes during deglaciation across the northwestern Canadian Shield, covering an area in excess of 1,000,000 km2 as the ice sheet retreated some 600 km. The interactions between proglacial lakes and ice sheet flow are explored, with a particular emphasis on whether the disposition of lakes may have influenced the location of the Dubawnt Lake ice stream. This ice stream falls outside the existing paradigm for ice streams in the Laurentide Ice Sheet because it did not operate over fined-grained till or lie in a topographic trough. Ice margin positions and a digital elevation model are utilised to predict the geometry and depth of proglacial lakes impounded at the margin at 30-km increments during deglaciation. Palaeogeographic reconstructions match well with previous independent estimates of lake coverage inferred from field evidence, and results suggest that the development of a deep lake in the Thelon drainage basin may have been influential in initiating the ice stream by inducing calving, drawing down ice and triggering fast ice flow. This is the only location alongside this sector of the ice sheet where large (>3000 km2), deep lakes (∼120 m) are impounded for a significant length of time and exactly matches the location of the ice stream. It is speculated that the commencement of calving at the ice sheet margin may have taken the system beyond a threshold and was sufficient to trigger rapid motion but that once initiated, calving processes and losses were insignificant to the functioning of the ice stream. It is thus concluded that proglacial lakes are likely to have been an important control on ice sheet dynamics during deglaciation of the Laurentide Ice Sheet. [Copyright &y& Elsevier]

The present paper addresses the question of rudist assemblages and their interpretation in terms of ecological entities, i.e. communities. Quantitative studies performed on rudist assemblages in the Barremian platform carbonates of the Marseille region (SE France) were based on biological attributes (shell size, shell thickness, packing density, packing index, coverage and shell contribution) and sedimentological attributes from the associated substrate (mud content, grain size and skeletal contribution to the sediment and bed thickness). The studied samples were originally ascribed to four assemblages defined on the basis of semiquantitative data.Contrasting results were obtained from multivariate analysis applied to biological then to biological plus sedimentological data. The latter documents four groups of samples in correspondence with the former assemblages. This grouping refers directly or indirectly to critical attributes of communities: biomass and substrate. Evidence for some taxonomic markers and because the assemblages represent recurrent statistical entities corroborate their interpretation as palaeocommunities.The method proposed here for the reconstruction of rudist palaeocommunities has a potential for unravelling biological assemblages with a low taxonomic resolution. [Copyright &y& Elsevier]

Palaeocene molluscan faunas are characterised by complex evolutionary histories following the Cretaceous–Tertiary (K–T) boundary extinction event and exhibit dramatic, distinct signatures of composition and biodiversity levels relating to extinction and post-extinction recovery processes. This paper is the first to document and survey the entire Palaeocene record of the Southern Hemisphere, which comprises at least 515 recorded molluscan taxa from Australia, New Zealand/Chatham Islands, Antarctica, and South America. The record is much richer than previously recognised. The K–T boundary event was a prime mechanism of change for the composition of Palaeocene faunas, but Palaeocene diversity patterns were shaped also by the final break-up of Gondwana, concomitant changes in climate and in oceanic circulation, and faunal recovery processes. The ‘flip-flop’ in diversity of bivalves and gastropods across the K–T boundary stems from a rapid, evolutionary burst of speciation in the Danian for gastropods, especially carnivorous forms with planktotrophic development, which infilled ecospace vacated by the extinction. In the Southern Hemisphere fossil record, deposit feeders were less affected by the extinction event and seemingly more extinction-resistant, but other important factors related to stratigraphic range and spectrum of life habits/habitats affected survivorship success. Suspension feeders, especially epifaunal forms, were hard hit by the extinction, but had bounced back within a few million years by late Danian time at the latest, but at lower diversity than during the Late Cretaceous. The extinction was not as marked in most southern regions, as reflected in the Antarctic record. In the Antarctic K–T boundary interval, diversity drops suddenly ca 50 m before the boundary, and while suspension feeders remain at low diversity for at least 300 kyr, gastropods still dominate the molluscan assemblages. Most of the K–T boundary molluscan survivors were bivalve species (66%) and all of these were members of representative genera that displayed extensive stratigraphic and geographic ranges in the Cretaceous or earlier in the Mesozoic. The majority of earliest Danian Antarctic molluscs belong to newly evolved species within surviving genera (58%), but by late Danian time this trend had changed to a dominance of new species in new genera. Many new groups arose during the Palaeocene, especially by late Danian time, and these faunas are highly distinctive at both genus and species level. For example, the Wangaloa Formation fauna of late Danian age (ca 63–61 Ma) is dominated by new species in new genera, ranging in values from 62.5 to 81%. A systematic catalogue of all known Palaeocene Austral species is presented herein in the for the first time with details of formation recorded, age, and inferred life habits. [Copyright &y& Elsevier]

Marine sedimentary rocks of the lower Miocene Monte León Formation of southeastern Patagonia (Austral Basin), Argentina are important geological archives for better understanding regional tectonics, paleoenvironments, oceanography, and climate. In this paper, we describe assemblages of invertebrates, palynomorphs, foraminifera, ostracods and calcareous nannofossils in a stratigraphical and sedimentological framework, which suggest deposition during a transgressive-regressive cycle. From base to top, the lowermost outcropping deposits of the Punta Entrada Member represent an inner shelf environment, formed during a transgressive phase. The zone of maximum flooding is marked by a high diversity of protoperidiniaceans (heterotrophic) and offshore dinoflagellate cysts, an increase in the percentage and size of planktonic foraminifera, and a decrease in shallow water benthic foraminifera. Regressive deposits in the upper part of the Punta Entrada Member exhibit a progradational stratal stacking pattern and are characterized by an upward decrease in bioturbation and in the content of marine invertebrates; the dinoflagellate cyst assemblages point toward shallower and more restricted marine conditions than in underlying deposits. The cycle ends with the Monte Observación Member, which contains an impoverished and mostly reworked fauna of invertebrates. The presence of monospecific reefs of Crassostrea orbignyi , the decrease in dinoflagellate cysts and calcareous microfossils diversity, and the increase of continental palynomorphs suggest progressively shallower conditions and increasing influence of freshwater discharge. Although eustatic controls could have contributed to the sedimentary evolution of the Monte León Formation, the upward regressive trend is interpreted as the result of tectonism linked to the Andean orogeny, which led to the uplift, exhumation, and erosion of the highlands in the west. This is supported by the abundance of pyroclastic material, together with reworked specimens of Upper Cretaceous forams and Upper Cretaceous and middle Eocene dinoflagellate cysts in the upper part of the Punta Entrada Member and in the Monte Observación Member. • Multiproxy data indicate that study rocks represent a transgressive-regressive cycle. • A maximum flooding and/or higher organic flux zone was identified at the coastal cliffs. • The regressive trend was the result of tectonics, sediment supply dynamics, and volcanism. • Cretaceous/Eocene forams and dinocysts evidence exhumation and reworking from the Andes. [ABSTRACT FROM AUTHOR]

The present paper is a report of work completed by the group ‘Friends of Paleobiogeography’ on the principles of palaeobiogeographic classification and nomenclature of palaeobiogeographic units (biochoremas). These principles are intended to complement those of neobiogeography and are aimed at enhancing palaeobiogeography in general by a simplified and standardised terminology. [Copyright &y& Elsevier]