Vegetation, climate and palaeoaltitude reconstructions of the Eastern Alps during the Miocene based on pollen records from Austria, Central Europe

Aim To reconstruct the flora, vegetation, climate and palaeoaltitude during the Miocene (23.03–5.33 Ma) in Central Europe. Location Six outcrop sections located in different basins of the Central Paratethys in Austria. Methods Pollen analysis was used for the reconstruction of the vegetation and climate. The altitude of the Eastern Alps that are adjacent to the Alpine Foreland and Vienna basins has been estimated using a new quantification method based on pollen data. This method uses biogeographical and climatological criteria such as the composition of the modern vegetation belts in the European mountains and Miocene annual temperature estimates obtained from fossil pollen data. Results Pollen changes from Early to Late Miocene have been observed. The vegetation during the Burdigalian and Langhian (20.43–13.65 Ma) was dominated by thermophilous elements such as evergreen trees, typical of a present‐day evergreen rain forest at low altitudes (i.e. south‐eastern China). During the Serravallian and Tortonian (13.65–7.25 Ma) several thermophilous elements strongly decreased, and some disappeared from the Central European region. This kind of vegetation was progressively substituted by one enriched in deciduous and mesothermic plants. Middle‐altitude (Cathaya, Cedrus and Tsuga) and high‐altitude (Abies and Picea) conifers increased considerably during the Langhian and later on during the Serravallian and Tortonian. Main conclusions Pollen changes are related to climatic changes and to the uplift of the Alpine massifs. The vegetation during the Burdigalian and Langhian reflects the Miocene climatic optimum. The decrease in thermophilous plants during the Serravallian and Tortonian can be interpreted as a climatic cooling and can be correlated with global and regional climatic changes. This study shows that the palaeoaltitude of the eastern part of the Eastern Alps during the Burdigalian was not high enough for Abies and Picea to form a forest. Therefore, we inferred that the summits of most of the mountains would have been less than 1800 m. The substantial increase of middle‐ and high‐altitude conifers in the pollen spectra suggests that the uplift rate increased during the Langhian in this region. Based on higher palaeoaltitude estimations for the pollen floras from the studied sections of Austria, we infer that the uplift of the easternmost part of the Alpine chain continued during the Serravallian and Tortonian.     

Change in diversity,ecological significance and biogeographical relationships of the Mediterranean Miocene toothed whale fauna

The main evolutionary trend in the Mediterranean Miocene toothed whale fauna is related (1) to the change in diversity and (2) to the turnover in community structure. Diversity increases from Upper Aquitanian–Lower Burdigalian to Burdigalian–Langhian, when it reaches its maximum. Starting from this time, diversity decreases progressively. The Early Miocene (Upper Aquitanian–Lower Burdigalian) Mediterranean toothed whale fauna, as well as the extramediterranean ones, is characterised by a high number of endemic taxa and by the prevalence of longirostral forms living in estuarine-neritic environments. A more diversified fauna spreading in neritic and pelagic environments characterises the Burdigalian–Langhian age, while an increase in pelagic forms and the nearly complete disappearance of some archaic longirostral taxa is typical of the Serravallian–Messinian fauna. Decrease in diversity and disappearance of archaic longirostral taxa are also recorded, at more general scale, in the Late Miocene extramediterranean fossil bearing deposits. These events can be related to the progressive global climatic deterioration, starting from Middle Miocene. From a biogeographic point a view, we can outline some relationships between the Mediterranean and western North Atlantic Miocene faunas. Closer affinities are observed between the Baltringen fauna and the northern Atlantic one, because of the presence of the genera Pomatodelphis and Zarhachis (platanistids) in both areas. In the Miocene Mediterranean and in North Atlantic, the delphinids are apparently absent as well as other extant delphinoid groups even if erroneously recorded in the past.     

Vegetation and climate reconstructions on different time scales in China: a review of Chinese palynological research

This paper reviews vegetation and climate reconstructions for different time scales based on palynological studies in China. It discusses examples of significant developments in palynological research topics within China: (1) Modern pollen—a modern pollen database (East Asia Surface Pollen Database) has been established through the collaboration of Chinese palynologists. Based on these data, modern pollen distributions and their quantitative relationship with vegetation and climate have been thoroughly studied. (2) Pre-Quaternary vegetation and climate dynamics—scientists have mapped pollen and palaeobotanical data from the Palaeogene. The vegetation distributions confirm a north–south zonal pattern during the Palaeogene that changed to an east–west monsoonal pattern during the Miocene and Pliocene. These results provide key evidence for understanding monsoon evolution. (3) Late-Quaternary vegetation—biome reconstructions based on fossil pollen data show spatial and temporal changes in vegetation since the Last Glacial Maximum, permitting a better understanding of climate change across China. (4) Quantitative climate reconstructions—some reconstructions have successfully detected Holocene climate variability thereby providing insights into monsoon history. At present, there are no comprehensive spatial reconstructions. Major possible future developments should focus on: (1) long-term vegetation reconstructions from lakes to study Asian monsoon dynamics at orbital scales; (2) quantitative reconstructions of vegetation and climate change to help stronger integration with palaeoclimate models and dynamic vegetation models; (3) land-cover and land-use change across China over the last 6,000 years to understand human impacts and provide empirical data for climate modellers; and (4) integration of pollen data with vegetation and climate modelling to understand the CO₂-vegetation relationship and climate dynamics.     

Depositional environment changes during the early–late Serravallian boundary dated by the Central Paratethys bioevents

The early–late Serravallian boundary (Badenian–Sarmatian) is a key interval for understanding Central Paratethys evolution. Environmental changes resulted in a great regional faunal turnover known as the Badenian-Sarmatian extinction event (BSEE). Here, we present a high-resolution sedimentological and biostratigraphical study from a rare site located on the Vienna and Danube basin junction (Slovakia). Four Middle Miocene depositional cycles/episodes ranked between 13.1 and 12.6 Ma are described in detail: (1) early Serravallian (13.1 Ma or older) shallow-marine episode; (2) early Serravallian (Badenian; Bulimina–Bolivina biozone; ~13.1 Ma or younger) outer shelf cycle; (3) late Serravallian (Sarmatian; large Elphidia biozone; ~12.6 Ma or younger) inner shelf cycle; (4) late Serravallian? A sedimentary episode represented by a scour filled with a reworked Serravallian (Upper Badenian and Sarmatian) material. The middle Miocene strata are overlaying and discordantly separated by Quaternary fluvial (floodplain) sediments (2.58 Ma or younger). These episodes reflect the early–late Serravallian turnover documented in the bioevents and in the sedimentological record.     

Integrated stratigraphy of the Early Miocene lacustrine deposits of Pag Island (SW Croatia): Palaeovegetation and environmental changes in the Dinaride Lake System

An integrated stratigraphic study of a Neogene lacustrine succession on the Pag Island (Croatia), combining quantitative pollen analysis, magnetostratigraphy, cyclostratigraphy, biostratigraphy and gamma-ray measurements, provides new insights into orbitally controlled variations in palaeo-vegetation and depositional patterns in the Dinaride Lake System. The quantitative palynological record shows a cyclical pattern of vegetation changes that closely corresponds to sedimentological patterns. The intervals with a high abundance of thermophilous and xeric indicators, suggesting a warm and dry climate, generally coincide with intervals of frequent lignite deposition and shallow lake facies. This suggests that both records are dominantly controlled by variations in past climatic conditions and lake level. Our data show two large-scale warming and shallowing-upward cycles, which are interpreted to be forced by the ~ 100 kyr eccentricity cycle of the Earth's orbit. Magnetostratigraphic data of the examined section reveal a long (113 m) reversed polarity interval, followed by a 7 m thick interval of normal polarity at the top. The inferred depositional rate of ~ 0.3 mm/yr, combined with biostratigraphic constraints by mollusks, suggests that the most logical correlation of the reversed interval is to chron C5Cr. This indicates that the Pag succession was deposited between 17.1 and 16.7 Ma and that it corresponds to the Burdigalian Stage of the Early Miocene, and the regional Karpatian Stage of the Central Paratethys. The high relative percentage of thermophilous pollen taxa, Engelhardia and Taxodium-type being the most prominent, generally indicates a subtropical humid climate for the SW Croatian part of the Dinaride Lake System. The observed warming trend is possibly related to the onset of the Miocene Climatic Optimum.     

Facies architecture and depositional development of Middle Miocene carbonate strata at Siwa Oasis, Northwestern Egypt

Based on microfacies analyses and sedimentological data, 17 facies are identified within the Middle Miocene carbonates at Siwa Oasis in the northern Western Desert of Egypt. These facies are attributed to five main facies belts. Within these facies and facies belts, five foraminiferal assemblages are recognized. A depositional model relates the reported facies and biofacies to a down-dip depositional profile of an inner to middle carbonate ramp. The facies of the peritidal to restricted lagoon (facies belt 1) and the less-restricted lagoon (facies belt 2) were deposited in the inner ramp behind the barrier/beach shoal facies belt 3. Basinward, lime mudstone of facies belts 4 and 5 accumulated in a proximal to distal middle ramp, respectively. The depositional evolution involved three stages, which are strongly controlled by tectonics and eustatic sea-level changes. The first stage comprises the transgressive Lower Miocene clastic-dominated fluvial facies of the Moghra Formation. The second stage heralds the deposition of the Langhian inner-ramp carbonate and shale facies of the basal Oasis Member of the Marmarica Formation under a relatively high stand of sea level, constrained clastic influx and climate warming. The final stage is represented by Langhian to Serravallian mid-ramp carbonate-dominated facies of the Siwa Escarpment and El Diffa Plateau members under fluctuating sea level, and a westward restriction in clastic supply and water turbidity.     

Early Miocene repetitive vegetation and climatic changes in the lacustrine deposits of the Rubielos de Mora Basin (Teruel, NE Spain)

Pollen analysis of a Lower Miocene succession from the Rubielos de Mora Basin (NE Spain) has been carried out with the aim of reconstructing the flora, vegetation and climatic changes. Previous paleobotanical studies on these sedimentary rocks and adjacent areas interpreted very diverse climates for the Early Miocene: from humid temperate to dry subtropical. In this study, a rich thermophilous pollen spectrum and a diverse subarid flora including Nitraria, Caesalpiniaceae, Ephedra and Acacia, indicative of a dry subtropical climate are identified. On the other hand, mesothermic taxa with high water requirements are also abundant. Therefore, the pollen assemblages evidence the juxtaposition of very contrasted environments: the presence of subdesertic taxa, typical of plants growing in the lowlands and conditioned by a long warm, dry season, together with others with very high water requirements, needing constant water. This can be explained by the presence of the Rubielos de Mora Lake providing local conditions for developing riparian forests. The vegetation was clearly controlled by the water availability under a subtropical and dry-seasonal climate. Pollen changes along the succession, which coincide with sedimentological changes, are related to climatic variations. Alternation in pollen taxa (thermophilous–dry vs. mesothermic–riparian) reflects the influence of the cyclicity of temperature and precipitation on the lake level and vegetation.     

Pollen analysis of coal-bearing Miocene sedimentary rocks from the Seyitömer Basin (Kütahya), Western Anatolia

The late Early-Middle Miocene sequences of the Seyitömer Basin (western Anatolia) were palynologically investigated. Fifty-five taxa belonging to seven gymnospermous and 48 angiospermous pollen genera were identified in the 19 productive samples. Two pollen zones were recognised based on the changing abundance of individual tree taxa. Zone 1 is characterized by predominance of Pinus and Cedrus. Zone 2 is characterized by predominance of deciduous Quercus and evergreen Quercus and a marked reduction in representation of Taxodiaceae. The differences in the pollen spectra between Zone 1 and Zone 2 may reflect the global Middle Miocene cooling. These results are largely comparable to pollen data derived from the neighbouring areas. The vegetation of the Seyitömer Basin was dominated by trees. This palynological analysis reveals the existence of a swamp-forest developed in a subtropical to warm-temperate humid climate.     

Les faunes de Scléractiniaires dans les faluns du Miocène moyen d'Atlantique-Est (bassins de la Loire et d'Aquitaine) : paléobiogéographie et évolution climatique

The Aquitaine and Loire basins show in the Middle Miocene numerous marine littoral deposits, often shelly or crag-type. Scleractinia are present, with a distribution and an abundance very variable according to the outcrops. A detailed study of all the available material, recently or historically cropped, allowed to draw up an accurate faunal inventory and to compare the distribution of taxa between the two basins. Out of 90 taxa in total, 62 are known in Aquitaine and 48 in Loire. In the Aquitaine Langhian, when is noted an obvious reduction of hermatypic taxa in comparison with the rich regional Burdigalian faunas, the association includes 44 species (25 reef-building ones). In the Serravallian, the reef-building taxa become significantly scarce and are residual (9 taxa out of 33 in Aquitaine, present in levels belonging to the lower sequence of the stage, and located in sheltered internal parts of the south-Aquitaine and central-Aquitaine gulfs). In the Loire basin, the corals are quite diversified in the Pontilevian facies (19 reef-building taxa out of 48), and much scarcer in the Lublean and Savignean facies. Globally, the Scleractinia are few abundant everywhere. If in the two basins hermatypic taxa persisted in the Langhian, indicating subreefal-type facies, varied factors have impeded permanently the settlement of reefs. In comparison with the Burdigalian, the thermic deterioration gradient, evidenced since the Chattian on the northeastern Atlantic frontage, had an important influence, and the Langhian waters were only subtropical. Other factors acted, at least locally, as the hydrodynamics, the bathymetry, the kind of substratum, the salinity pro parte. Moreover, a latitudinal gradient between the two basins is evidenced by the global species richness and by the ratio of hermatypicity, created here and defined as the fraction of hermatypic taxa reported to ahermatypic ones from a same basin. This ratio can be used at generic level or specific one as well. In the Serravallian, when the diversity was everywhere obviously lower, the influence of the climatic gradient went on, together with other unfavourable conditions (often abundant detritic supplies, high hydrodynamics, spatial biocompetition). Diverse biogeographic and paleogeographic data are also reported. A vast East-Atlantic coralline bioprovince, settled as early as the Chattian with a dispersion center located in Aquitaine, was still active in the Middle Miocene, when large transgressions favoured the faunal exchanges; its history was to be completed at the end of this period.     

An 18 million year record of vegetation and climate change in northwestern Canada and Alaska: tectonic and global climatic correlates

We reconstruct long-term vegetation/paleoclimatic trends, spanning the last 18 million years, in Alaska, Yukon and far western Northwest Territories. Twenty-one average percentage spectra for pollen and spores are assembled from eight surface/subsurface sections. The sections are dated independently or by correlation. Pollen and spore ratios indicate the direction of change in vegetation and climatic parameters — growing season temperature (T_est), tree canopy density (C_est) and paludification at study sites (P_est). A global warm peak ca. 15 Ma is shown by the abundance of thermophilous taxa, including Fagus and Quercus. A temperature decline immediately following 15 Ma parallels climatic reconstructions based on marine oxygen isotopes. Subsequent declines correlate to the Messinian event and the onset of late Pliocene-Pleistocene glaciation. After 7 Ma herbs and shrubs become more important elements of the palynological assemblages, suggesting a more continental, colder/drier climate. However, a late Pliocene warm interval is evident. Vegetation/climatic changes during the early to late Miocene show synchrony with, and are most economically attributable to, global events. After 7 Ma, vegetation/climate change is attributed primarily to latest Miocene-to-Pleistocene uplift of the Alaska Range and St. Elias Mts. The continuing influence of global climatic patterns is shown in the late Pliocene warm interval, despite uplift to the south. The opening of the Bering Strait ca. 3 Ma may have moderated the climate in the study area.     

Late Miocene vegetation and climate reconstruction based on pollen data from the Sofia Basin (West Bulgaria)

The analysis of fossil palynomorh assemblages in the Late Miocene freshwater sediments of the Sofia Basin (West Bulgaria) was done to collect data on the vegetation and climate dynamics during the Late Miocene. On the basis of pollen data, we described the main palaeocomunities developed in the region. The mixed mesophytic forests dominated the vegetation in which species of Quercus, Ulmus, Zelkova, Fagus, Carpinus, Betula, Castanea, Corylus, Pterocarya, Carya, Juglans, and Eucommia played important roles. Swamp forests were also recorded, including Taxodiaceae, Alnus, Glyptostrobus, Nyssa, and Myrica. Herbaceous vegetation was distributed in the middle part of the section, with a maximum of 35.5%. The vegetation dynamic passes through several phases, which were associated with changes in paleoclimate and palaeoecological conditions. Coexistence Approach (CA) was applied to palynological data to calculate four climatic parameters. The values of coexistence intervals for mean annual temperatures are 13.6–16.6 °C, with winter temperatures being 3.7–6.6 °C and summer temperatures being 23.6–27.8 °C. Mean annual precipitation ranged most frequently between 828 and 1308 mm. The palaeoclimatic reconstruction illustrates existence of a warm-temperate and relatively humid climate with higher mean annual temperature than the present day climate.     

Middle to Upper Miocene benthonic foraminiferal palaeoecology of the Tap Marls (Alicante Province,SE Spain) and its palaeoceanographic implications

The benthonic foraminiferal faunas of twenty sections have been analysed statistically (cluster analysis) and interpreted palaeoecologically. The analysis shows that oxygenation was the most important factor for the distribution of the faunas in the investigated area. The lifting and lowering of the sill to the Atlantic Ocean (Gibraltar sill), in conjunction with climatic changes and sea level fluctuations, led to changes in the current system and to two faunal turnovers at the transition from Langhian to Serravallian (∼15.2–15.0 Ma) and at the end of the Serravallian, respectively (∼11.7–11.4 Ma). The faunas indicate well oxygenated (Langhian), reduced oxygenated (Serravallian) and again well oxygenated (Tortonian) conditions. A simplified circulation model for the western Mediterranean, based on the author's interpretation and additional sources, suggests: (a) an estuarine circulation during the Langhian; (b) a `restricted' anti-estuarine pattern with sluggish circulation until the end of the Serravallian; and (c) an anti-estuarine circulation similar to today's situation during the Tortonian.     

Floristic and vegetational changes in the Iberian Peninsula during Jurassic and Cretaceous

The successive vegetations inhabiting the Iberian Peninsula from the Triassic/Jurassic boundary to the Cretaceous/Tertiary Boundary is reviewed based on published palynological and macrofloral data, and the vegetational changes set in a palaeogeographical and climate context. Xerophytic microphyllous coniferous forests and pteridophyte communities of arid environments dominated the Jurassic and earliest Cretaceous vegetation. This vegetation was replaced in the mid Early Cretaceous by mixed forests of pteridophytes, gymnosperms and angiosperms. The composition of the successive plant assemblages suggests that a subtropical arid climate generally prevailed in the Iberian Peninsula during Jurassic-Cretaceous, although palaeobotanical and sedimentological evidences suggest that the climate was not uniform through the whole interval and that were two episodes in the Tithonian-Berriasian and Aptian-Albian periods of pronounced dry and/or arid environmental conditions. The composition and structure of the vegetation was not only affected by evolutionary changes but also by successive global geographical and climate changes. Hence, significant changes in the distribution of continental areas during the Mesozoic resulted in the latitudinal or sublatitudinal extensions of the climatic belts.     

Palaeoecological perspectives on pattern and process in plant diversity and distribution adjustments: a comment on recent developments*

Two developments in the understanding of the relationship between sedimentary pollen assemblages, vegetation and plant diversity are discussed. The Prentice model of vegetation–pollen relationships has improved our understanding of how and at what scale sedimentary pollen records vegetation. The modelling framework allows improved palaeoecological study designs that may, potentially, give important new insights into processes of plant migrations in response to climate change. Also, reconstructions of plant communities and landscape openness may be improved. Competing hypotheses for the relationship between vegetation and palynological diversity are discussed and it is concluded that more attention should be focused on evenness aspects of palynological diversity and on hypothesis testing.     

Vegetation changes during the Holocene in the North Ibersá, Corrientes, Argentina

Vegetation changes during the Holocene in the North Iberá, Corrientes, Argentina. Wetlands are very important sites for palynological studies, since they represent one of the most suitable environments for fossil pollen preservation. The aim of this work was to determine, by palynological analysis of lacustrine sediments, the vegetal communities and the predominant environment during the Holocene in NW of Iberá. Two lagoons were studied: San Sebastián and San Juan Poriahú. Sediment samples were obtained with witness using a "Levingstone square-rod sampler", processed with Faegri e Iversen techniques and dated with C14. The palynological graphs were divided in zones using the Tilia program. The palynological analysis allowed visualizing diverse changes in the vegetation: from 6 140 +/- 50 to 5 170 +/- 100 a. C., the NW of Iberá was characterized by marsh-herbaceous vegetation and arboreal vegetation typical of dry vegetation. From 5 170 +/- 100 to 3 460 +/- 60 a. C., a decrease in the species frequency, typical of wet environments, is produced, and the clogging of the waterbody, from 3460 +/- 60 a. C. onwards, while continuing the dominance of herbaceous vegetation typical of these environments, the arboreal pollen, indicates the beginning of a hygrophilous forest development.     

西欧地中海地区中新世以来的植被演化和现代地中海植被的形成

从距今2500万年的中新世初到更新世,欧洲地中海沿岸地区的植被是从东亚型的热带——亚热带常绿阔叶林逐渐过渡为旱生性的蒿——藜草原。古热带和亚洲、北美成份从晚中新世起逐渐消失,少数一直延续到中更新世。孢粉分析表明,地中海成分从中上新世起有明显增加,地中海常绿硬叶林的发展与北极冰盖的形成密切相关。     

New Zealand climate in the Neogene and implications for global atmospheric circulation

New Zealand has a good Neogene plant fossil record. During the Miocene it was without high topography and it was highly maritime, meaning that its climate, and the resulting vegetation, would be controlled dominantly by zonal climate conditions. Its vegetation record during this time suggests the climate passed from an ever-wet and cool but frostless phase in the Early Miocene in which Nothofagus subgenus Brassospora was prominent. Then it became seasonally dry, with vegetation in which palms and Eucalyptus were prominent and fires were frequent, and in the mid-Miocene, it developed a dry-climate vegetation dominated by Casuarinaceae. These changes are reflected in a sedimentological change from acidic to alkaline chemistry and the appearance of regular charcoal in the record. The vegetation then changed again to include a prominent herb component including Chenopodiaceae and Asteraceae. Sphagnum became prominent, and Nothofagus returned, but mainly as the subgenus Fuscospora (presently restricted to temperate climates). This is interpreted as a return to a generally wet, but now cold climate, in which outbreaks of cold polar air and frost were frequent. The transient drying out of a small maritime island and the accompanying vegetation/climate sequence could be explained by a higher frequency of the Sub-Tropical High Pressure (STHP) cells (the descending limbs of the Hadley cells) over New Zealand during the Miocene. This may have resulted from an increased frequency of ‘blocking’, a synoptic situation which occurs in the region today. An alternative hypothesis, that the global STHP belt lay at a significantly higher latitude in the early Neogene (perhaps 55°S) than today (about 30°S), is considered less likely because of physical constraints on STHP belt latitude. In either case, the difference between the early Neogene and present situation may have been a response to an increased polar-equatorial temperature gradient. This contrasts with current climate models for the geological past in which the latitude of the High Pressure belt impact is held invariant though geological time.     

Holoplanktonic gastropoda (Mollusca) from the Miocene of Cyprus: systematics and biostratigraphy

Abstract: Eleven randomly chosen outcrops in the Miocene Pakhna Formation of Cyprus were sampled for holoplanktonic Mollusca. Four species of Heteropoda were found, and 24 of Pteropoda, a substantial increase from the two species recorded until now from the Miocene of Cyprus. One pteropod species, Peracle charlotteae sp. nov. (Gastropoda, Pseudothecosomata), is introduced. Age assignments based on holoplanktonic molluscs for the 11 localities are as follows: Langhian (Alassa 1–4), (Serravallian?) Tortonian to Messinian (Episkopi 1), Tortonian (Agios Tychon, Tokhni and the Maroni Marlstone of Khirokitia 1–2) and Tortonian to Early Messinian (Episkopi 2). These age determinations in some cases are at odds with those from previous publications based on calcareous nannofossils and Foraminifera. The sediments underlying the Amathus Channel outcrop yielded insufficient fauna for definitive dating, but we suggest are younger than Late Serravallian. At some localities, particularly in the Alassa area, pteropod assemblages are strongly variable on a bed‐by‐bed basis, and this offers possibilities for future refined biostratigraphical interpretations. This is the first substantial holoplanktonic mollusc fauna described from the eastern Mediterranean basin and allows correlation with assemblages in the central Mediterranean and elsewhere.     

A taphonomic approach to the genetic interpretation of clypeasteroid accumulations from the Miocene of Tarragona,NE Spain

Belaústegui, Z., Nebelsick, J.H., Gibert, J.M. de, Domènech, R. & Martinell, J. 2012: A taphonomic approach to the genetic interpretation of clypeasteroid accumulations from the Miocene of Tarragona, NE Spain. Lethaia, Vol. 45, pp. 548–565. Clypeasteroid accumulations are common in Cenozoic shallow marine sediments, particularly in the Neogene, as they are also in analogue modern environments. In this article, four clypeasteroid accumulations from Miocene (Serravallian) shallow marine carbonates of the El Camp de Tarragona Basin (NE Spain) are studied. Two of them are dominated by flat‐shaped Parascutella, whereas the other two consist exclusively of bell‐shaped Clypeaster. The combination of the taphonomic analysis of the tests, the palaeoecological and taphonomic information provided by the associated fossils, and the stratigraphical and sedimentological context of each one of these beds allows interpreting them as autochthonous/parautochthonous accumulations resulting from in situ reworking in moderate energy settings, except for one that constitutes a true sand dollar coquina deposited by a storm event. This contribution explores the potential of thorough taphonomic analysis of marine invertebrate skeletal concentrations and substantiates the importance of clypeasteroid echinoids as producers of shell beds in the Neogene. □ Clypeasteroids, Echinoids, Miocene, Taphonomy, Tarragona.     

Centennial- to decadal scale environmental shifts in and around Lake Pannon (Vienna Basin) related to a major Late Miocene lake level rise

A detailed ultra-high-resolution analysis of a 37-cm-long core of Upper Miocene lake sediments of the long-lived Lake Pannon has been performed. Despite a general stable climate at c. 11-9 Ma, several high-frequency oscillations of the paleoenvironments and depositional environments are revealed by the analysis over a short time span of less than 1000 years. Shifts of the lake level, associated with one major 3rd order flooding are reflected by all organisms by a cascade of environmental changes on a decadal scale. Within a few decades, the pollen record documents shifting vegetation zones due to the landward migration of the coast; the dinoflagellate assemblages switch towards "offshore-type" due to the increasing distance to the shore; the benthos is affected by low oxygen conditions due to the deepening. This general trend is interrupted by smaller scale cycles, which lack this tight interconnection. Especially, the pollen data document a clear cyclicity that is expressed by iterative low pollen concentration events. These "negative" cycles are partly reflected by dinoflagellate blooms suggesting a common trigger-mechanism and a connection between terrestrial environments and surface waters of Lake Pannon. The benthic fauna of the core, however, does not reflect these surface water cycles. This forcing mechanism is not understood yet but periodic climatic fluctuations are favoured as hypothesis instead of further lake level changes. Short phases of low precipitation, reducing pollen production and suppressing effective transport by local streams, might be a plausible mechanism. This study is the first hint towards solar activity related high-frequency climate changes during the Vallesian (Late Miocene) around Lake Pannon and should encourage further ultra-high-resolution analyses in the area.