Wolfram Michael Kürschner

• Zhang, Xiaoqing; Royer, Dana L.; Colombi, Carina E.; Drovandi, Juan Martin; McElwain, Jennifer C. & Guignard, Gaëtan [Vis alle 24 forfattere av denne artikkelen] (2025). Fossil leaf cuticle: Best practices for preparation and paleo-CO2 analysis. Earth-Science Reviews. ISSN 0012-8252. 264. doi: 10.1016/j.earscirev.2025.105104. Fulltekst i vitenarkiv Vis sammendrag

  Leaf cuticle is the waxy envelope that protects leaves from desiccation, UV damage, and abrasion. The cuticle encodes information about a plant's chemistry and leaf epidermal and stomatal cell morphology. Fossil leaf cuticle has been used to determine taxonomic affinities for almost two centuries and recognized in recent decades for its value in reconstructing paleoenvironments and paleoclimates, especially atmospheric CO2. Fossil leaf cuticle preparation techniques are typically reported as single workflows tied to individual studies, starting with finding fossils in the field through the steps of preparing cuticle for chemical and morphological analysis, including decisions about type of microscopy and level of sampling effort at different spatial scales (number of fields-of-view, leaves, and species). The siloed nature of these publications makes finding appropriate methods and workflows for new studies difficult, especially for less experienced researchers. Here, we attempt to synthesize a breadth of existing workflows and make recommendations to guide methodological decision-making for new studies, with a particular focus on paleo-CO2 reconstruction via a proxy based on leaf gas-exchange principles (the Franks model). We describe and annotate chemical procedures for preparing cuticles for analysis and include recommendations regarding leaf conditions for which each is most appropriate. For studies making repeated measures of morphology (e.g., stomatal density), we describe a resampling routine that can guide decision-making, in real time, about sampling effort.

• Baranyi, V; Budai, Tamãs; Karadi, Viktor; Jin, Xin; Kürschner, Wolfram Michael & Toth, Emöke (2025). Vegetation and climate record across the Carnian Pluvial episode from the Transdanubian Range, Hungary, Western Tethys. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 671. doi: 10.1016/j.palaeo.2025.112989. Fulltekst i vitenarkiv Vis sammendrag

  The Carnian Pluvial Episode (CPE) is one of the most extensively studied Triassic hyperthermal events that triggered biological turnovers both on land and in the marine realm. From a palynological perspective, the CPE is marked by a notable increase in the hygrophytic spore-pollen assemblages compared to the early Late Triassic. In the Transdanubian Range (Western Hungary), Carnian mixed clastic‑carbonate successions indicate a relatively wetter climate and elevated terrestrial input into the basins during the CPE. The quantitative and qualitative palynological data from three borehole successions provided insight into the Julian and early Tuvalian vegetation history of the study area. The new palynostratigraphical data refined the age constraints of the CPE deposits spanning from the late Julian to early Tuvalian correlated to the Duplicisporites continuus zone from the Alpine Realm. Palynological marker taxa characteristic for the middle to late Tuvalian were absent, confirming that the well-documented hiatus between the CPE deposits and the Main Dolomite extends over large parts of the Tuvalian. A complex interplay between regional and global processes influenced the palynological assemblages that responded to both eustatic sea-level changes and climatic fluctuations. The climate change in the Julian 2 was not uniform and seemingly expressed in the palynofloras of the Transdanubian Range with a delay due to transgression, as the palynological assemblage were still predominantly characterized by xerophytic conifer pollen in the pelagic depositional site in the early CPE phase, and even they might point to highly seasonal climate at the onset of the event inferred from the proliferation of the Enzonalasporites group. Hygrophytic vegetation elements such as spores and cycad-bennettite pollen peaked only in the late Julian 2. Variations in the relative abundance of spores, cycad-bennettite pollen and marine palynomorphs showed the combined effects of local sea-level changes and humid climatic episodes in controlling terrestrial influx from the latest Julian 2–Tuvalian onwards. The palynofloras point to aridification from later in the early Tuvalian, indicating the waning of the pluvial phase.

• Wu, Quingting; Nsingi, Joseph M.; Kürschner, Wolfram Michael; Beaty, Brian J.; Planavsky, Noah J. & Schneebeli-Hermann, Elke [Vis alle 9 forfattere av denne artikkelen] (2025). Impacts of volcanism on geochemical records during the Late Permian-Early Triassic transition in northern and middle Norwegian continental margins. Global and Planetary Change. ISSN 0921-8181. 252. doi: 10.1016/j.gloplacha.2025.104874. Fulltekst i vitenarkiv Vis sammendrag

  The end-Permian mass extinction (EPME; ∼252 Ma), known as the largest extinction event during the Phanerozoic Eon, provides a critical case study to understand the impacts of anthropogenic climate change. The warming associated with the EPME was likely triggered by the emissions of large quantities of CO2 during the eruption of the voluminous Siberian Traps (ST) volcanism, which eliminated 80 to 90 % of marine species and 70 % of terrestrial species. However, the links between volcanism, negative carbon isotope excursions (nCIEs), chemical weathering, oceanic anoxia, and biotic turnover remain poorly understood. To better understand these connections, we analyze organic carbon isotopes, major element, and trace element geochemistry from two shallow marine sites at the Finnmark and Trøndelag Platforms in Norway, which serve as proxies for tracing volcanic-induced biogeochemical perturbations. Enhanced chemical weathering across the PTB at the Finnmark Platform and during the earliest Triassic at the Trøndelag Platform is indicated by increases in chemical weathering proxies (CIA, CIW, PIA, and Rb/Sr ratios) and decreases in WIP, along with indirect support from Li enrichment. At the Finnmark Platform, transient enrichments in primary productivity-sensitive elements (P and Ni) precede the PTB, but these signals likely result from a combination of nutrient input and localized lithological controls rather than a direct increase in marine productivity. This phase coincides with a brief period of reduced oxygen availability, as indicated by elevated UEF, VEF, and U/Th ratios, followed by a return to more oxygenated conditions. In contrast, at the Trøndelag Platform, sustained enrichment of PEF, NiEF, UEF, and U/Th ratios during the earliest Triassic suggests episodic oxygen depletion was likely driven by sediment redeposition processes rather than persistent euxinia or continuous biological productivity. The contrasting geochemical responses observed at the two platforms highlight the complexity of regional environmental feedbacks during the EPME, highlighting the importance of integrating multiple geochemical proxies in tracking environmental responses to climate change.

• Tekin, U. Kagan; Krystyn, Leopold; Kürschner, Wolfram Michael; Sayit, Kaan; Okuyucu, Cengiz & Forel, Marie-Béatrice (2024). Development of the early Carnian deepening upward sequence of the Huglu Unit within the tectonic slices/blocks of the Mersin Mélange, southern Turkey: Biochronologies, geochemistry of volcaniclastics and palaeogeographic implications. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 636. doi: 10.1016/j.palaeo.2023.111964. Fulltekst i vitenarkiv
• Li, Liqin; Xu, Yuanyuan; Wang, Yongdong & Kürschner, Wolfram Michael (2023). Palynological investigation of an Upper Triassic sequence in Nanjing area, eastern China, with paleoecological implications. Geobios. ISSN 0016-6995. 80, s. 43–54. doi: 10.1016/j.geobios.2023.07.002. Fulltekst i vitenarkiv
• Gravendyck, Julia; Coiffard, Clément; Bachelier, Julien B. & Kürschner, Wolfram Michael (2023). Re-evaluation of Cerebropollenites thiergartii Eberh.Schulz 1967 and related taxa: priority of Sciadopityspollenites and nomenclatural novelties. Grana. ISSN 0017-3134. 62(1), s. 1–47. doi: 10.1080/00173134.2022.2158688. Fulltekst i vitenarkiv Vis sammendrag

  The important marker species for the base of the Jurassic, Cerebropollenites thiergartii, occurs contemporaneously with at least nine related taxa. However, their distinction is difficult and has been confused in the past. In addition, a long history of numerous recombinations with different genus names (e.g. Tsugaepollenites and Sciadopityspollenites), and inconsistent classifications or synonymisations, further complicate the taxonomic framework of Cerebropollenites thiergartii. A comprehensive study of these ten taxa, summarising their crucial distinctive characteristics and potential synonymy, is currently missing. This limits the stratigraphic value of Cerebropollenites thiergartii and associated taxa relevant to the Triassic–Jurassic transition. Here, we revisit relevant holotype material, related taxa and investigated new material for potential interspecific and intraspecific morphological variation. Based on an empirical analysis of name use and an extensive literature review, we identified previous sources of confusion, re-evaluated the distinctive characteristics and stratigraphic value of these taxa, and their relevance for the Triassic–Jurassic transition. Finally, we argue that the recombination as Sciadopityspollenites thiergartii is taxonomically and nomenclaturally imperative, not only due to priority, but also because it unifies previous disjunct use of Cerebropollenites for Mesozoic and Sciadopityspollenites for Cenozoic taxa, or Mesozoic species in many Russian studies. Thus, we propose a series of nomenclatural novelties: Sciadopityspollenites emend., Sciadopityspollenites thiergartii comb. nov. et emend., S. thiergartii ssp. nov. thiergartii, S. thiergartii ssp. multiverrucosus stat. nov., S. megaorbicularius sp. nov., S. carlylensis comb. nov. et emend., S. serratus emend., S. macroverrucosus emend., S. mesozoicus emend., Cryptopalynites gen. nov., Cryptopalynites pseudomassulae comb. nov. et emend.

• Hönisch, Bärbel; Royer, Dana L.; Breecker, Daniel O.; Polissar, Pratigya Jeremy; Bowen, Gabriel J. & Henehan, Michael James [Vis alle 84 forfattere av denne artikkelen] (2023). Toward a Cenozoic history of atmospheric CO<inf>2</inf>. Science. ISSN 0036-8075. 382(6675). doi: 10.1126/science.adi5177. Fulltekst i vitenarkiv Vis sammendrag

  The geological record encodes the relationship between climate and atmospheric carbon dioxide (CO2) over long and short timescales, as well as potential drivers of evolutionary transitions. However, reconstructing CO2 beyond direct measurements requires the use of paleoproxies and herein lies the challenge, as proxies differ in their assumptions, degree of understanding, and even reconstructed values. In this study, we critically evaluated, categorized, and integrated available proxies to create a high-fidelity and transparently constructed atmospheric CO2 record spanning the past 66 million years. This newly constructed record provides clearer evidence for higher Earth system sensitivity in the past and for the role of CO2 thresholds in biological and cryosphere evolution.

• Bang, Emil; Nakrem, Hans Arne; LITTLE, CRISPIN T.S.; Kürschner, Wolfram Michael; Kelly, Simon R.A. & Smelror, Morten (2022). Palynology of Early Cretaceous (Barremian to Aptian) hydrocarbon (methane) seep carbonates and associated mudstones, Wollaston Forland, Northeast Greenland. Acta Palaeobotanica. ISSN 0001-6594. 62(1), s. 11–23. doi: 10.35535/acpa-2022-0002. Fulltekst i vitenarkiv Vis sammendrag

  Palynostratigraphic and palynofacies analysis have been performed on hydrocarbon seep carbonate, carbonate nodule and mudstone samples from the Early Cretaceous Kuhnpasset Beds in the Kuhnpasset area of Wollaston Forland, Northeast Greenland. Three informal palynostratigraphic zones have been defined based on dinoflagellate cyst occurrences. The zones range from ?early Barremian to early Aptian in age, and correlate with previously defined dinoflagellate cyst zones in Northeast Greenland. These zones indicate hydrocarbon seepage in Kuhnpasset spanned the ?early–late Barremian age range, but did not continue into the Aptian, and thus seep activity continued for as much as three million years. Palynofacies analysis is used to interpret the depositional environment of the Kuhnpasset Beds and indicate that the hydrocarbon seeps and associated mudstones from this sedimentary sequence were deposited in a proximal shelf setting.

• Li, Liqin; Kürschner, Wolfram Michael; Lu, Ning; Chen, Hongyu; An, Pengcheng & Wang, Yongdong (2022). Palynological record of the Carnian Pluvial Episode from the northwestern Sichuan Basin, SW China. Review of Palaeobotany and Palynology. ISSN 0034-6667. 304. doi: 10.1016/j.revpalbo.2022.104704. Fulltekst i vitenarkiv Vis sammendrag

  The prevailing arid Late Triassic climate was interrupted by a humid Carnian Pluvial Episode (CPE) during the mid-Carnian period. In this study, a palynological study was conducted for the Ma'antang Formation (Carnian) from the northwestern Sichuan Basin, SW China, in the eastern Tethys. The study reveals dominance of terrestrial palynomorphs, and two palynological assemblage zones were identified. Palynofloras are well-presented by dominant ferns (especially Dipteridaceae/Matoniaceae), with less abundant lycopsids, conifers, cycadophytes/ginkgophytes and seed ferns. Overwhelming predominance of wet Lowland SEG and hygrophyte elements, and increased Lowland/Hinterland as well as hygrophyte/xerophyte ratios observed in Units 2–4 of the Ma'antang Formation, suggesting intensified humidity during the Julian 2 in this area. This study presents the first palynological evidence for vegetation changes in South China during the CPE, and correlates well with observations from North China as well as western Tethys, thus further supports worldwide impact of humid climate associated with the CPE.

• Lu, Ning; Wang, Yongdong; Xu, Yuanyuan; Li, Liqin; Xie, Xiaoping & Popa, Mihai Emilian [Vis alle 9 forfattere av denne artikkelen] (2022). Oscillations of a fluvial-lacustrine system and its ecological response prior to the end-Triassic: Evidence from the eastern Tethys region. Geological Journal. ISSN 0072-1050. doi: 10.1002/gj.4658. Fulltekst i vitenarkiv Vis sammendrag

  The end-Triassic mass extinction is considered one of the “Big Five” extinction events in the Phanerozoic. However, whether the terrestrial ecosystem began to deteriorate or even collapse prior to the Triassic–Jurassic (Tr-J) transition remains controversial. Compared with the documented data from the western Tethyan region, evidence from the eastern Tethyan realm is limited. We undertake a fitting analysis of the sedimentary system, floral community successions and major geological events of the Xujiahe Formation as reflected by the Qilixia Section, Xuanhan area, northeast Sichuan Basin, China. Our results reveal an oscillating fluvial-lacustrine depositional system during the Late Triassic, with the dominant sedimentary processes mainly controlled by the Indosinian Movement. Beside the sedimentary influence on the Xujiahe Flora, climate changes played a more important role. Fluctuating conditions to cooler and dryer climates at this time promoted diversification of gymnosperms under an overall warm and humid climate setting in the Late Triassic in the Xuanhan area. Superimposed on this oscillating long-term climate state, ecosystem destabilization occurred over 1 million years prior to the Tr–J interval in the Xuanhan study area, possibly in response to the intensified storm and wildfire activity and the following environmental changes. Although the Xujiahe Flora always recovered from the interruption of the tectonic movement, it ultimately collapsed under extreme climatic events and ecological pressures induced by the Late Triassic Central Atlantic Magmatic Province event.

• Steinthorsdottir, Margret; Coxall, Helen K.; Boer, Agatha M. De; Huber, Matthew; Barbolini, Natasha & Bradshaw, C. D. [Vis alle 23 forfattere av denne artikkelen] (2021). The Miocene: The Future of the Past. Paleoceanography and Paleoclimatology. 36(4). doi: 10.1029/2020PA004037. Fulltekst i vitenarkiv Vis sammendrag

  The Miocene epoch (23.03–5.33 Ma) was a time interval of global warmth, relative to today. Continental configurations and mountain topography transitioned toward modern conditions, and many flora and fauna evolved into the same taxa that exist today. Miocene climate was dynamic: long periods of early and late glaciation bracketed a ∼2 Myr greenhouse interval—the Miocene Climatic Optimum (MCO). Floras, faunas, ice sheets, precipitation, pCO2, and ocean and atmospheric circulation mostly (but not ubiquitously) covaried with these large changes in climate. With higher temperatures and moderately higher pCO2 (∼400–600 ppm), the MCO has been suggested as a particularly appropriate analog for future climate scenarios, and for assessing the predictive accuracy of numerical climate models—the same models that are used to simulate future climate. Yet, Miocene conditions have proved difficult to reconcile with models. This implies either missing positive feedbacks in the models, a lack of knowledge of past climate forcings, or the need for re-interpretation of proxies, which might mitigate the model-data discrepancy. Our understanding of Miocene climatic, biogeochemical, and oceanic changes on broad spatial and temporal scales is still developing. New records documenting the physical, chemical, and biotic aspects of the Earth system are emerging, and together provide a more comprehensive understanding of this important time interval. Here, we review the state-of-the-art in Miocene climate, ocean circulation, biogeochemical cycling, ice sheet dynamics, and biotic adaptation research as inferred through proxy observations and modeling studies.

• Cui, Ying; Li, Mingsong; Soelen, Elsbeth Ester van; Peterse, Francien & Kürschner, Wolfram Michael (2021). Massive and rapid predominantly volcanic CO2 emission during the end-Permian mass extinction. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 118(37). doi: 10.1073/pnas.2014701118. Fulltekst i vitenarkiv Vis sammendrag

  The end-Permian mass extinction event (∼252 Mya) is associated with one of the largest global carbon cycle perturbations in the Phanerozoic and is thought to be triggered by the Siberian Traps volcanism. Sizable carbon isotope excursions (CIEs) have been found at numerous sites around the world, suggesting massive quantities of 13 C-depleted CO 2 input into the ocean and atmosphere system. The exact magnitude and cause of the CIEs, the pace of CO 2 emission, and the total quantity of CO 2 , however, remain poorly known. Here, we quantify the CO 2 emission in an Earth system model based on new compound-specific carbon isotope records from the Finnmark Platform and an astronomically tuned age model. By quantitatively comparing the modeled surface ocean pH and boron isotope pH proxy, a massive (∼36,000 Gt C) and rapid emission (∼5 Gt C yr −1 ) of largely volcanic CO 2 source (∼−15%) is necessary to drive the observed pattern of CIE, the abrupt decline in surface ocean pH, and the extreme global temperature increase. This suggests that the massive amount of greenhouse gases may have pushed the Earth system toward a critical tipping point, beyond which extreme changes in ocean pH and temperature led to irreversible mass extinction. The comparatively amplified CIE observed in higher plant leaf waxes suggests that the surface waters of the Finnmark Platform were likely out of equilibrium with the initial massive centennial-scale release of carbon from the massive Siberian Traps volcanism, supporting the rapidity of carbon injection. Our modeling work reveals that carbon emission pulses are accompanied by organic carbon burial, facilitated by widespread ocean anoxia.

• Zhou, Ning; Xu, Yuanyuan; Li, Liquin; Lu, Ning; An, Pengcheng & Popa, Mihai Emilian [Vis alle 9 forfattere av denne artikkelen] (2021). Pattern of vegetation turnover during the end-Triassic mass extinction: Trends of fern communities from South China with global context. Global and Planetary Change. ISSN 0921-8181. 205. doi: 10.1016/j.gloplacha.2021.103585. Fulltekst i vitenarkiv Vis sammendrag

  The end-Triassic mass extinction (ETME) is considered to be one of the five most severe extinction events in Earth history and caused the disappearance of ca. 80% of all species. The terrestrial ecosystems were also greatly affected by this extinction, but the severity of the land plant diversity loss is not well understood. Ferns are once a principal component of the terrestrial ecosystem from the late Paleozoic/early Mesozoic era and colonizers taxa commonly found in disturbed environments. In this study, we investigated the diversity and ecology of fern during the Triassic-Jurassic (Tr–J) transition in the Sichuan Basin of South China and focused for the first time on the impact of the end-Triassic mass extinction event on the fern communities. We assembled fern fossil records in 16 localities from the Rhaetian Xujiahe (XJH) Formation to the lowermost Jurassic Zhenzhuchong (ZZC) Formation. Our results indicate that no obvious mass extinctions of macro-microflora of ferns but a clear species turnover was recorded at ETME in the Sichuan Basin, reflected an appropriate response of plants in places far away from CAMP volcanism. The paleoecological analysis based on macroflora and microflora in the Sichuan Basin shows a warm and humid condition of tropical-subtropical climate during Rhaetian followed by an increase of specific dry-resistant taxa, indicating a dryer environment at the Earliest Jurassic. Additionally, multivariate statistical approaches (principal coordinates analysis, cluster analysis, network analysis) for fern macro-remains and spores data in the southeastern Sichuan Basin infer that the members of XJH and ZZC Formation cluster in three groups, corresponding to their environmental conditions, determined by humidity and temperature.

• Zaputlyaeva, Alexandra; Mazzini, Adriano; Blumenberg, Martin; Scheeder, Georg; Kürschner, Wolfram Michael & Kus, Jolanta [Vis alle 8 forfattere av denne artikkelen] (2020). Recent magmatism drives hydrocarbon generation in north-east Java, Indonesia. Scientific Reports. 10. doi: 10.1038/s41598-020-58567-6. Fulltekst i vitenarkiv Vis sammendrag

  Conventional studies of petroleum basins associate oil generation with the gradual burial of organic-rich sediments. These classical models rely on the interplay between pressure, temperature, and the time required for organic matter transformation to oil and gas. These processes usually occur over geological timescales, but may be accelerated by rapid reactions when carbon-rich sediments are exposed to migrating magmatic fluids. The spectacular Lusi eruption (north-east Java, Indonesia) is the surface expression of the present-day deep interaction between volcanic and sedimentary domains. Here we report the ongoing generation of large amounts of hydrocarbons induced by a recent magmatic intrusion from the neighbouring Arjuno-Welirang volcanic complex. We have investigated a unique suite of oil and clast samples, and developed a detailed conceptual model for the complex hydrocarbon migration history in this part of the basin by integrating multidisciplinary techniques. Our results show that palynology, organic petrology, and chlorite microthermometry are the most sensitive geothermometers for basins affected by recent magmatic activity. These findings further our understanding of the driving mechanisms fueling the world’s largest active mud eruption and provide a unique dataset to investigate modern hydrocarbon generation processes.

• Ruffell, Alastair & Kürschner, Wolfram Michael (2020). Sediment Cyclicity and the Carnian Pluvial Episode: Evidence from Spectral Gamma ray Logging of the Mercia Mudstone Group, SW England. Boletino Geologico y Minero. 131(2), s. 231–242. doi: 10.21701/bolgeomin.131.2.002. Fulltekst i vitenarkiv Vis sammendrag

  The Late Triassic exposed on the Devon coast (SW England) is analysed through spectral gamma-ray logging and considered in terms of two theories of palaeoenvironmental change: sediment cyclicity and the Carnian Pluvial Episode (CPE). A decrease in total count gamma-ray output occurs at the CPE and reflects a geographically extensive change in depositional styles from siltstones and isolated playa-lake, evaporitic mudstones to more geographically- widespread evaporite-bearing mudstone cycles. Th/K and Th/U ought to increase (through humid weathering) in the CPE, but these ratios do not change until above the CPE-related Dunscombe Mudstone Formation. A delayed response in Th enrichment is considered likely, reacting to both the initiation of the 1.2my long CPE, but also longerterm and widespread Carnian rifting, marine inundation and volcanism in Pangaea.

• Gravendyck, Julia; Schobben, Martin A.N.; Bachelier, Julien B. & Kürschner, Wolfram Michael (2020). Macroecological patterns of the terrestrial vegetation history during the end-Triassic biotic crisis in the central European Basin: A palynological study of the Bonenburg section (NW-Germany) and its supra-regional implications. Global and Planetary Change. ISSN 0921-8181. doi: 10.1016/j.gloplacha.2020.103286. Fulltekst i vitenarkiv
• Li, Liqin; Wang, Yongdong; Kürschner, Wolfram Michael; Ruhl, Micha & Vajda, Vivi (2020). Palaeovegetation and palaeoclimate changes across the Triassic–Jurassic transition in the Sichuan Basin, China. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 556. doi: 10.1016/j.palaeo.2020.109891. Fulltekst i vitenarkiv
• Zhou, Ning; Wang, Yongdong; Ya, Li; Porter, Amanda S.; Kürschner, Wolfram Michael & Li, Liquin [Vis alle 8 forfattere av denne artikkelen] (2020). An inter-comparison study of three stomatal-proxy methods for CO2 reconstruction applied to early Jurassic Ginkgoales plants. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 542. doi: 10.1016/j.palaeo.2019.109547. Fulltekst i vitenarkiv
• Stokkebekk, Even; Nordeng, Eirik N.; Dypvik, Henning; Småkasin, Rikke Øya; Sørhus, Kathrine & Kürschner, Wolfram Michael (2019). Sedimentological and palynological investigations of the Neoproterozoic Valdres Group. Norwegian Journal of Geology. ISSN 2387-5844. 99(4), s. 575–582. doi: 10.17850/njg99-4-2. Fulltekst i vitenarkiv Vis sammendrag

  The Valdres Group (?Cryogenian) has been sedimentologically and stratigraphically studied and sampled in a few key sites (Grønsennknippa, Mellane, Ormtjernkampen). The search for fossils in selected formations has been the target and one identified acantomorphic acritarch was discovered along with other organic matter of more uncertain heritage. In addition to the diamictite/tillite present in the Valdres Group succession, this facilitates a correlation with the well-known Hedmark Group to the east.

• Baranyi, Viktoria; Rostasi, Agnes; Raucsik, Bela & Kürschner, Wolfram Michael (2019). Palynology and weathering proxies reveal climatic fluctuations during the Carnian Pluvial Episode (CPE) (Late Triassic) from marine successions in the Transdanubian Range (western Hungary). Global and Planetary Change. ISSN 0921-8181. 177, s. 157–172. doi: 10.1016/j.gloplacha.2019.01.018. Fulltekst i vitenarkiv Vis sammendrag

  In the early Late Triassic, the Carnian Pluvial Episode (CPE) is a phase with increased siliciclastic influx into the marine-carbonate dominated depositional setting of the Western Tethys assumingly caused by a shift to more humid climatic conditions and increased continental runoff. Here, vegetation changes inferred from the palynological assemblages and weathering proxies (αAli) have been studied from the Transdanubian Range (TR), western Hungary to reveal climate variations and detect episodes with hygrophytic vegetation and enhanced continental hydrolysis. Palynostratigraphy has been applied to correlate the clastic pulses known from elsewhere in the Western Tethys. The quantitative palynological analysis indicates a shift towards hygrophytic elements in the Julian 2, and return to xerophytic associations in the Tuvalian. The increase in the hygrophytic vegetation elements is coincident with elevated kaolinite and partially with the increase of α-values indicating strong terrestrial runoff, enhanced continental hydrolysis and more humid climate in the lower part of the Veszprém Formation in the early Julian 2. The wetter conditions in the Julian 2 were periodically interrupted by shorter periods of drier climate manifested in the progradation of carbonate platforms and the deposition of carbonate series and breccias interbedded between the marl units. In the late Julian 2 the high amount of hygrophytes points to another humid episode, but the decrease of kaolinite in the clay mineral profile and the weathering indices might suggest stronger seasonality. Although, the multiple clastic pulses in the western Tethys were related primarily to more humid climate during the CPE, the comparison to clay mineralogy and weathering proxies suggest a more complicated scenario in the TR. The enhanced continental weathering related to a more humid climate is only suggested for the lower part of the Veszprém Formation in the early stages of the CPE in the Julian 2.

• Baranyi, Viktoria; Rostasi, Agnes; Raucsik, Bela & Kürschner, Wolfram Michael (2019). Palynological and X-ray fluorescence (XRF) data of Carnian (Late Triassic) formations from western Hungary. Data in Brief. 23. doi: 10.1016/j.dib.2019.103858. Fulltekst i vitenarkiv Vis sammendrag

  The data presented in this article are related to the research article “Palynology and weathering proxies reveal climatic fluctuations during the Carnian Pluvial Episode (CPE) (Late Triassic) from marine successions in the Transdanubian Range (western Hungary)” (Baranyi et al., 2019). Palynological and palynofacies counts and mineralogical data are presented that build the core for the palaeoenvironmental and palaeoclimatic interpretation discussed in the original research article. Other component of this data article is the description of the applied laboratory and analytical techniques. We also supply microscopic images of the identified pollen and spores and a list of all identified palynomorphs.

• Baranyi, Viktoria; Miller, Charlotte Sarah; Ruffell, Alastair; Hounslow, Mark W. & Kürschner, Wolfram Michael (2019). A continental record of the Carnian Pluvial Episode (CPE) from the Mercia Mudstone Group (UK): palynology and climatic implications. Journal of the Geological Society. ISSN 0016-7649. 176(1), s. 149–166. doi: 10.1144/jgs2017-150. Fulltekst i vitenarkiv Vis sammendrag

  The generally arid Late Triassic climate was interrupted by a wet phase during the mid-Carnian termed the Carnian Pluvial Episode (CPE). Quantitative palynological data from the Mercia Mudstone Group in the Wessex Basin (UK) reveal vegetation changes and palaeoclimate trends. Palynostratigraphy and bulk organic carbon isotope data allow correlation to other Carnian successions. The palynostratigraphy indicates that the Dunscombe Mudstone is Julian and the lowest part of the overlying Branscombe Mudstone Formation is Tuvalian. The Aulisporites acme characterizing the CPE in Tethyan successions and the Germanic Basin is missing in the UK. The quantitative palynological record suggests the predominance of xerophyte floral elements with a few horizons of increased hygrophytes. A humidity signal is not seen owing to the dry climate in central Pangea. Also, the signal might be masked by the overrepresentation of xerophyte regional pollen and the predominance of xerophyte hinterland flora. The bias towards regional pollen rain is enhanced by the potential increase in continental runoff related to seasonally humid conditions and differences in pollen production rates and transport mechanisms. The vegetation of British CPE successions suggests a more complex climate history during the Carnian, indicating that the CPE is not recognized by the same changes everywhere.

• Iqbal, Shahid; Wagreich, Michael; U, Jan Irfan; Kürschner, Wolfram Michael; Gier, Susanne & Bibi, Mehwish (2019). Hot-house climate during the Triassic/Jurassic transition: The evidence of climate change from the southern hemisphere (Salt Range, Pakistan). Global and Planetary Change. ISSN 0921-8181. 172, s. 15–32. doi: 10.1016/j.gloplacha.2018.09.008. Fulltekst i vitenarkiv
• Schobben, Martin; Gravendyck, Julia; Mangels, Franziska; Struck, Ulrich; Bussert, Robert & Kürschner, Wolfram Michael [Vis alle 9 forfattere av denne artikkelen] (2019). A comparative study of total organic carbon-δ13C signatures in the Triassic–Jurassic transitional beds of the Central European Basin and western Tethys shelf seas. Newsletters on stratigraphy. ISSN 0078-0421. 52(4), s. 461–486. doi: 10.1127/nos/2019/0499. Fulltekst i vitenarkiv Vis sammendrag

  Stratigraphic studies are an integral component in understanding the chronology of events that led to the end-Triassic mass extinction, by resolving causal relationships between environmental upheavals and biotic response. Successful correlation of Triassic–Jurassic (Tr–J) successions is complicated by the disappearance of macro-fossils that are otherwise central components in stratigraphic studies. This problem is exacerbated in multiple Tr–J sections situated in Europe, where the so-called “Event Beds” – assumed to demarcate the extinction interval – are virtually devoid of fossils. An alternative stratigraphic approach entails the reconstruction of carbon isotope records, where stratigraphic fluctuations in carbon isotope composition are considered to track changes in the global biogeochemical carbon cycle. The predominance of carbonate-lean sections has prompted the reconstruction of total organic carbon (TOC)-based carbon isotope records. However, bulk rock derived TOC is the diagenetically stabilized remnant of organic components that accumulated on the sea floor, and which can originate from multiple sources. In this study, we assess long-term TOC-based carbon isotope trends at two sites: Bonenburg (Central European Basin) and Kuhjoch (the Tr–J Global Stratotype Section and Point; western Tethys shelf seas). We focus on the TOC 13C-enrichment of the Event Beds with the aim of deciphering stratigraphic fluctuations in relation to their main driver (the exogenic carbon pool versus organic matter source changes). By studying the systematic co-variance of several sedimentary parameters (TOC, total nitrogen [TN], and the palynomorph composition), we infer that the TOC composition is possibly characterized by insignificant organic matter source changes in terms of the marine and terrestrial organic carbon contributions. By contrast, a clay mineralogical shift to more K-depleted minerals as well as the elevated occurrence of wood fragments in the Event Beds suggest a terrestrial organic matter source shift from immature substrates to substrates predominated by “pre-aged” or “fossil organic matter” under a changing continental weathering regime. This outcome urges for reservations when interpreting TOC-based carbon isotope records in terms of global C-cycle perturbations, especially when coinciding with lithological and mineralogical changes. On a more positive note, the shift towards positive carbon isotope values appears to be a recurring feature, possibly testifying to a globally significant climate-controlled weathering regime shift.

• Lerch, Benedikt; Karlsen, Dag Arild; Thießen, Olaf; Abay, Tesfamariam Berhane; Soelen, Elsbeth Ester van & Kürschner, Wolfram Michael [Vis alle 8 forfattere av denne artikkelen] (2018). Investigations on the use of triaromatic dimethylcholesteroids as age-specific biomarkers in bitumens and oils from Arctic Norway. Organic Geochemistry. ISSN 0146-6380. 122, s. 1–16. doi: 10.1016/j.orggeochem.2018.04.011. Fulltekst i vitenarkiv
• Olsen, Paul E.; Geissman, John W.; Kent, Dennis V.; Gehrels, George E.; Mundil, Roland & Irmis, Randall B. [Vis alle 27 forfattere av denne artikkelen] (2018). Colorado Plateau Coring Project, Phase I (CPCP-I): A continuously cored, globally exportable chronology of Triassic continental environmental change from western North America. Scientific Drilling. ISSN 1816-8957. 24, s. 15–40. doi: 10.5194/sd-24-15-2018. Fulltekst i vitenarkiv Vis sammendrag

  Phase 1 of the Colorado Plateau Coring Project (CPCP-I) recovered a total of over 850 m of stratigraphically overlapping core from three coreholes at two sites in the Early to Middle and Late Triassic age largely fluvial Moenkopi and Chinle formations in Petrified Forest National Park (PFNP), northeastern Arizona, USA. Coring took place during November and December of 2013 and the project is now in its post-drilling science phase. The CPCP cores have abundant detrital zircon-producing layers (with survey LA-ICP-MS dates selectively resampled for CA-ID-TIMS U-Pb ages ranging in age from at least 210 to 241 Ma), which together with their magnetic polarity stratigraphy demonstrate that a globally exportable timescale can be produced from these continental sequences and in the process show that a prominent gap in the calibrated Phanerozoic record can be filled. The portion of core CPCP-PFNP13-1A for which the polarity stratigraphy has been completed thus far spans ∼215 to 209 Ma of the Late Triassic age, and strongly validates the longer Newark-Hartford Astrochronostratigraphic-calibrated magnetic Polarity Time-Scale (APTS) based on cores recovered in the 1990s during the Newark Basin Coring Project (NBCP). Core recovery was ∼100 % in all holes (Table 1). The coreholes were inclined ∼60–75∘ approximately to the south to ensure azimuthal orientation in the nearly flat-lying bedding, critical to the interpretation of paleomagentic polarity stratigraphy. The two longest of the cores (CPCP-PFNP13-1A and 2B) were CT-scanned in their entirety at the University of Texas High Resolution X-ray CT Facility in Austin, TX, and subsequently along with 2A, all cores were split and processed at the CSDCO/LacCore Facility, in Minneapolis, MN, where they were scanned for physical property logs and imaging. While remaining the property of the Federal Government, the archive half of each core is curated at the NSF-sponsored LacCore Core Repository and the working half is stored at the Rutgers University Core Repository in Piscataway, NJ, where the initial sampling party was held in 2015 with several additional sampling events following. Additional planned study will recover the rest of the polarity stratigraphy of the cores as additional zircon ages, sedimentary structure and paleosol facies analysis, stable isotope geochemistry, and calibrated XRF core scanning are accomplished. Together with strategic outcrop studies in Petrified Forest National Park and environs, these cores will allow the vast amount of surface paleontological and paleoenvironmental information recorded in the continental Triassic of western North America to be confidently placed in a secure context along with important events such as the giant Manicouagan impact at ∼215.5 Ma (Ramezani et al., 2005) and long wavelength astronomical cycles pacing global environmental change and trends in atmospheric gas composition during the dawn of the dinosaurs.

• Baranyi, Viktoria; Reichgeld, Tammo; Olsen, Paul E.; Parker, William G. & Kürschner, Wolfram Michael (2018). Norian vegetation history and related environmental changes: New data from the Chinle Formation, Petrified Forest National Park (Arizona, SW USA). Geological Society of America Bulletin. ISSN 0016-7606. 130(5-6), s. 775–795. doi: 10.1130/B31673.1. Fulltekst i vitenarkiv Vis sammendrag

  Fossil plant assemblages including spores and pollen grains provide useful information on past ecosystems and the response of terrestrial biotas to various environmental perturbations. New quantitative palynological data from the Chinle Formation of the American Southwest suggest that a floral turnover occurred in the middle Norian (between 217 and 213 Ma). Analysis of plant communities reveals that this turnover was followed by a complete reorganization of the riparian vegetation, driven by changes in fluvial styles and the tectonic regime of the basin, as well as a gradual transition toward a more arid climate. Marked increases in Klausipollenites gouldii, Patinasporites spp., and Froelichsporites traversei are probable indicators of environmental stress, such as increased aridity, perturbations of atmospheric pCO2, acid rain, and atmospheric aerosol accumulation due to volcanism in connection with the Pangean rifting and uplift of the Cordilleran arc. Comparison of the vegetation turnover with younger assemblages from the Chinle Formation in New Mexico revealed similar floral turnover patterns, suggesting two distinct drier periods as a result of multiple climatic oscillations. The climate-induced floral turnover may have contributed to the vertebrate faunal turnover as the loss of wetland habitat space and an increase in xerophytic plants may have dwindled the supply of palatable vegetation for herbivores. The onset of the floral turnover in Arizona roughly corresponds to the Manicouagan impact event, but a direct causal link is still speculative.

• Baranyi, Viktoria; Wellman, Charles H. & Kürschner, Wolfram Michael (2018). Ultrastructure and probable botanical affinity of the enigmatic sporomorph froelichsporites traversei from the norian (Late triassic) of North America. International journal of plant sciences. ISSN 1058-5893. 179(2), s. 100–114. doi: 10.1086/694762. Fulltekst i vitenarkiv Vis sammendrag

  Froelichsporites traversei is a prominent palynomorph in the Upper Triassic of North America that always occurs in tetrahedral permanent tetrads. It is an important regional biostratigraphic marker in the Norian of North America, and its abundance rises around 215 Ma, associated with a significant floral and faunal turnover. Its most striking morphological features are one well-developed distal pore (ulcus) on each grain and the annulus-like exine thickening around them. Previous works suggested that it was produced by spore-producing plants or Cheirolepidiaceae, but its botanical affinity is still unclear.

• Soelen, Elsbeth Ester van & Kürschner, Wolfram Michael (2018). Late Permian to Early Triassic changes in acritarch assemblages and morphology in the Boreal Arctic: New data from the Finnmark Platform. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 505, s. 120–127. doi: 10.1016/j.palaeo.2018.05.034. Fulltekst i vitenarkiv Vis sammendrag

  The Late Permian extinction interval is in many marine locations characterized by the development of anoxic conditions. The Finnmark Platform is one of few exceptions, as sedimentological and palynofacies evidence indicate oxygenated conditions throughout the event. Changes in acritarch assemblages and morphology were studied in order to better understand the link between acritarchs and environmental conditions. The main taxa are of Micrhystridium, Baltisphaeridium and leiospheres, while Veryhachium and the prasinophytes Cymatiosphaera and Tasmanites were present in low abundances. Increased concentrations of acritarchs, particularly Micrhystridium, show that the environmental changes at the start of the extinction event may have resulted in enhanced marine productivity. A shift from Micrhystridium/Baltisphaeridium dominance before and during the extinction event, to leiosphere-dominance after the extinction event, indicates a shift towards a more inshore environment. The new data are compared with published Late Permian acritarch records from East Greenland, China and Pakistan. A striking difference between the East Greenland and Finnmark Platform, which are both expanded Upper Permian/Lower Triassic sections, is that the acritarch record from Greenland shows a strong decrease in process length of the acritarch Micrhystridium. Together with a change in the acritarch assemblage, this change in morphology was interpreted to represent a decrease in salinity at the site, resulting from increased run-off. The differences between the East Greenland and the Finnmark records are likely due to their palaeogeographical settings, as the East Greenland section was located in a narrow and elongated basin which was likely more sensitive to evaporation and run-off changes than the Finnmark Platform.

• Soelen, Elsbeth Ester van; Twitchett, Richard & Kürschner, Wolfram Michael (2018). Salinity changes and anoxia resulting from enhanced run-off during the late Permian global warming and mass extinction event. Climate of the Past. ISSN 1814-9324. 14(4), s. 441–453. doi: 10.5194/cp-14-441-2018. Fulltekst i vitenarkiv Vis sammendrag

  The late Permian biotic crisis had a major impact on marine and terrestrial environments. Rising CO2 levels following Siberian Trap volcanic activity were likely responsible for expanding marine anoxia and elevated water temperatures. This study focuses on one of the stratigraphically most expanded Permian–Triassic records known, from Jameson Land, East Greenland. High-resolution sampling allows for a detailed reconstruction of the changing environmental conditions during the extinction event and the development of anoxic water conditions. Since very little is known about how salinity was affected during the extinction event, we especially focus on the aquatic palynomorphs and infer changes in salinity from changes in the assemblage and morphology. The start of the extinction event, here defined by a peak in spore : pollen, indicating disturbance and vegetation destruction in the terrestrial environment, postdates a negative excursion in the total organic carbon, but predates the development of anoxia in the basin. Based on the newest estimations for sedimentation rates, the marine and terrestrial ecosystem collapse took between 1.6 and 8 kyr, a much shorter interval than previously estimated. The palynofacies and palynomorph records show that the environmental changes can be explained by enhanced run-off and increased primary productivity and water column stratification. A lowering in salinity is supported by changes in the acritarch morphology. The length of the processes of the acritarchs becomes shorter during the extinction event and we propose that these changes are evidence for a reduction in salinity in the shallow marine setting of the study site. This inference is supported by changes in acritarch distribution, which suggest a change in palaeoenvironment from open marine conditions before the start of the extinction event to more nearshore conditions during and after the crisis. In a period of sea-level rise, such a reduction in salinity can only be explained by increased run-off. High amounts of both terrestrial and marine organic fragments in the first anoxic layers suggest that high run-off, increased nutrient availability, possibly in combination with soil erosion, are responsible for the development of anoxia in the basin. Enhanced run-off could result from changes in the hydrological cycle during the late Permian extinction event, which is a likely consequence of global warming. In addition, vegetation destruction and soil erosion may also have resulted in enhanced run-off. Salinity stratification could potentially explain the development of anoxia in other shallow marine sites. The input of fresh water and related changes in coastal salinity could also have implications for the interpretation of oxygen isotope records and seawater temperature reconstructions at some sites.

• Miller, Charlotte Sarah; Peterse, Francien; Silva, Anne-Christine da; Baranyi, Viktoria; Reichart, Gert-Jan & Kürschner, Wolfram Michael (2017). Astronomical age constraints and extinction mechanisms of the Late Triassic Carnian crisis. Scientific Reports. 7. doi: 10.1038/s41598-017-02817-7. Fulltekst i vitenarkiv Vis sammendrag

  The geological record contains evidence for numerous pronounced perturbations in the global carbon cycle, some of which are associated with mass extinction. In the Carnian (Late Triassic), evidence from sedimentology and fossil pollen points to a significant change in climate, resulting in biotic turnover, during a time termed the ‘Carnian Pluvial Episode’ (CPE). Evidence from the marine realm suggests a causal relationship between the CPE, a global ‘wet’ period, and the injection of light carbon into the atmosphere. Here we provide the first evidence from a terrestrial stratigraphic succession of at least five significant negative C-isotope excursions (CIE)’s through the CPE recorded in both bulk organic carbon and compound specific plant leaf waxes. Furthermore, construction of a floating astronomical timescale for 1.09 Ma of the Late Triassic, based on the recognition of 405 ka eccentricity cycles in elemental abundance and gamma ray (GR) data, allows for the estimation of a duration for the isotope excursion(s). Source mixing calculations reveal that the observed substantial shift(s) in δ13C was most likely caused by a combination of volcanic emissions, subsequent warming and the dissociation of methane clathrates.

• Hincke, Alexandra J.C.; Broere, Tom; Kürschner, Wolfram Michael; Donders, Timme H. & Wagner-Cremer, Friederike (2016). Multi-Year Leaf-Level Response to Sub-Ambient and Elevated Experimental CO2 in Betula nana. PLOS ONE. doi: 10.1371/journal.pone.0157400. Fulltekst i vitenarkiv
• Mueller, Steven; Hounslow, Mark W. & Kürschner, Wolfram Michael (2016). Integrated stratigraphy and palaeoclimate history of the Carnian Pluvial Event in the Boreal realm – new data from the Upper Triassic Kapp Toscana Group in central Spitsbergen (Norway). Journal of the Geological Society. ISSN 0016-7649. 173, s. 186–202. doi: 10.1144/jgs2015-028. Fulltekst i vitenarkiv
• Mueller, Steven; Krystyn, Leopold & Kürschner, Wolfram Michael (2016). Climate variability during the Carnian Pluvial Phase - A quantitative palynological study of the Carnian sedimentary succession at Lunz am See, Northern Calcareous Alps, Austria. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 441, s. 198–211. doi: 10.1016/j.palaeo.2015.06.008. Fulltekst i vitenarkiv
• Midtkandal, Ivar; Svensen, Henrik; Planke, Sverre; Corfu, Fernando; Polteau, Stephane & Torsvik, Trond Helge [Vis alle 11 forfattere av denne artikkelen] (2016). The Aptian (Early Cretaceous) oceanic anoxic event (OAE1a) in Svalbard, Barents Sea, and the absolute age of the Barremian-Aptian boundary. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 463, s. 126–135. doi: 10.1016/j.palaeo.2016.09.023. Fulltekst i vitenarkiv Vis sammendrag

  The age of the Cretaceous Barremian-Aptian boundary has been a long-standing problem in the geological timescale. Age suggestions range between 126 Ma and 117 Ma, making causal links between environmental crises and large-scale processes such as large igneous provinces (LIPs) problematic. New stratigraphic and radiometric data from three drillcores in Svalbard show that Barremian shelf siltstones and sandstones are overlain by Aptian shallow-marine mudstones. The organic carbon content in the mudstones is higher than 1.0 wt%, with values ranging up to 70 wt% in coal-dominated intervals. Carbon isotope measurements of the TOC show a negative δ13C excursion of 4.5‰ followed by a positive excursion of 6.7‰ within a 20-m interval, identified as the early Aptian Oceanic Anoxic Event 1a (OAE1a). This isotopic pattern of the excursion is in perfect agreement with excursions from lower latitude sections of the same age. A ~ 10-cm-thick zircon-bearing bentonite was discovered in the lower part of the Barremian, about 40 m below the OAE1a interval. U-Pb TIMS zircon analyses of two equivalent bentonites in adjacent boreholes gave a robust age of 123.1 ± 0.3 Ma. Based on the Barremian depositional systems, we estimate that a time interval of 1–2 Myr separates the bentonite and the OAE1a, providing an age of about 121–122 Ma for the Barremian-Aptian boundary. Our results stress that the geological timescale needs revision, and provide a benchmark test for the correlation between the OAE1a and LIPs in general.

• Schneebeli-Hermann, Elke; Kürschner, Wolfram Michael; Kerp, Hans; Bomfleur, Benjamin; Hochuli, Peter A. & Bucher, Hugo [Vis alle 8 forfattere av denne artikkelen] (2015). Vegetation history across the Permian–Triassic boundary in Pakistan (Amb section, Salt Range). Gondwana Research. ISSN 1342-937X. 27(3), s. 911–924. doi: 10.1016/j.gr.2013.11.007. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Mander, Luke & McElwain, Jennifer (2014). A gymnosperm affinity for Ricciisporites tuberculatus Lundblad: implications for vegetation and environmental reconstructions in the Late Triassic. Palaeobiodiversity and Palaeoenvironments. ISSN 1867-1594. 94(2), s. 295–305. doi: 10.1007/s12549-014-0163-y. Fulltekst i vitenarkiv
• Mueller, Steven; Veld, Harry; Nagy, Jenø & Kürschner, Wolfram Michael (2014). Depositional history of the upper triassic kapp toscana group on svalbard, Norway, inferred from palynofacies analysis and organic geochemistry. Sedimentary Geology. ISSN 0037-0738. 310, s. 16–29. doi: 10.1016/j.sedgeo.2014.06.003. Fulltekst i vitenarkiv
• Schneebeli-Hermann, Elke; Kürschner, Wolfram Michael; Hochuli, Peter A.; Ware, David; Weissert, Helmut & Bernasconi, Stefano M. [Vis alle 10 forfattere av denne artikkelen] (2013). Evidence for atmospheric carbon injection during the end-Permian extinction. Geology. ISSN 0091-7613. 41(5), s. 579–582. doi: 10.1130/G34047.1. Fulltekst i vitenarkiv
• Hillebrandt, Axel von; Krystyn, Leopold; Kürschner, Wolfram Michael; Bonis, Nina Rosa; Ruhl, Micha & Richoz, Silvain [Vis alle 13 forfattere av denne artikkelen] (2013). The Global Stratotype Sections and Point (GSSP) for the base of the Jurassic System at Kuhjoch (Karwendel Mountains, Northern Calcareous Alps, Tyrol, Austria). Episodes. ISSN 0705-3797. 36(3), s. 162–198. doi: 10.18814/epiiugs/2013/v36i3/001. Fulltekst i vitenarkiv Vis sammendrag

  The Global Stratotype Section and Point (GSSP) defining the base of the Jurassic System Lower Jurassic Epoch and Hettangian Stage is situated at the Kuhjoch pass, Karwendel Mountains, Northern Calcareous Alps, Austria (47°29'02"N/11°31'50"E). The Triassic-Jurassic (T-J) boundary is exposed at Kuhjoch West and at Kuhjoch East, and corresponds to the first occurrence (FO) of the ammonite Psiloceras spelae tirolicum. The “Golden Spike” was fixed at Kuhjoch East. The section displays a high and continuous sedimentation rate with a constant facies trend across the boundary level. Other bio-events include the FO of the aragonite foraminifer Praegubkinella turgescens, and of diverse ostracod species 1.0-3.40 cm below the FO of P. spelae and 3.2 m below P. spelae occurs the continental palynomorph Cerebropollenites thiergartii. Because of the lack of other terrestrial microfloral events this is yet the FO event closest to the FO of P. spelae and allows a correlation with nonmarine sediments. The d13Corg record shows a strong initial negative excursion at the boundary between the Kössen and Kendlbach formations, 5.8 m (Kuhjoch W) below the T-J boundary, a shift to more positive d13Corg in the Schattwald Beds and a gradual decline to more negative values at the transition of the Schattwald Beds to the proximate Tiefengraben Mb. The stratotype point lies within a zone of smaller negative and positive d13Corg peaks, which is superimposed on a longer lasting main negative shift. According to recent investigations, the radiometric age of the T-J boundary is about 201,3 Ma.

• Kürschner, Wolfram Michael; Batenburg, Sietske & Mander, Luke (2013). Aberrant Classopollis pollen reveals evidence for unreduced (2n) pollen in the conifer family Cheirolepidiaceae during the Triassic-Jurassic transition. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 280(1768:20131708). doi: 10.1098/rspb.2013.1708. Fulltekst i vitenarkiv
• Reichgelt, Tammo; Parker, William; Martz, Jeffrey; Conran, John; Cittert, Johanna van Konijnenburg-van & Kürschner, Wolfram Michael (2013). The palynology of the Sonsela member (Late Triassic, Norian) at Petrified Forest National Park, Arizona, USA. Review of Palaeobotany and Palynology. ISSN 0034-6667. 189, s. 18–28. doi: 10.1016/j.revpalbo.2012.11.001. Fulltekst i vitenarkiv
• Mander, Luke; Kürschner, Wolfram Michael & McElwain, Jennifer (2013). Palynostratigraphy and vegetation history of the Triassic-Jurassic transition on East Greenland. Journal of the Geological Society. ISSN 0016-7649. 170, s. 37–46. doi: 10.1144/jgs2012-018. Fulltekst i vitenarkiv
• Elke, Schneebeli-Hermann; Kürschner, Wolfram Michael; Hochuli, Peter A.; Bucher, Hugo; Ware, David & Goudemand, Nicolas [Vis alle 7 forfattere av denne artikkelen] (2012). Palynofacies analysis of the Permian-Triassic transition in the Amb section (Salt Range, Pakistan): Implications for the anoxia on the South Tethyan Margin. Journal of Asian Earth Sciences. ISSN 1367-9120. 60, s. 225–234. doi: 10.1016/j.jseaes.2012.09.005. Fulltekst i vitenarkiv
• Esmeijer-Liu, Alice; Kürschner, Wolfram Michael; Lotter, Andre F.; Verhoeven, Jos T. A. & Goslar, Tomasz (2012). Stable Carbon and Nitrogen Isotopes in a Peat Profile Are Influenced by Early Stage Diagenesis and Changes in Atmospheric CO2 and N Deposition. Water, Air and Soil Pollution. ISSN 0049-6979. 223(5), s. 2007–2022. doi: 10.1007/s11270-011-1001-8. Fulltekst i vitenarkiv
• Szurlies, Michael; Geluk, Mark C.; Krijgsman, Wout & Kürschner, Wolfram Michael (2012). The continental Permian-Triassic boundary in the Netherlands: Implications for the geomagnetic polarity time scale. Earth and Planetary Science Letters. ISSN 0012-821X. 317-318, s. 165–176. doi: 10.1016/j.epsl.2011.11.043. Fulltekst i vitenarkiv
• Bonis, Nina Rosa & Kürschner, Wolfram Michael (2012). Vegetation history, diversity patterns, and climate change across the Triassic/Jurassic boundary. Paleobiology. ISSN 0094-8373. 38(2), s. 240–264. doi: 10.1666/09071.1. Fulltekst i vitenarkiv
• Ruhl, Micha & Kürschner, Wolfram Michael (2011). Multiple phases of carbon cycle disturbance from large igneous province formation at the Triassic-Jurassic transition. Geology. ISSN 0091-7613. 39, s. 431–434. doi: 10.1130/G31680.1. Fulltekst i vitenarkiv
• Ruhl, M; Bonis, NR; Reichart, GJ; Damste, JSS & Kürschner, Wolfram Michael (2011). Atmospheric carbon injection linked to End-Triassic mass extinction. Science. ISSN 0036-8075. 333(6041), s. 430–434. doi: 10.1126/science.1204255. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Kürschner, Wolfram Michael; An, Pengcheng; Dons, Carl Erik & Nakrem, Hans Arne (2026). A new record of the conifer Quadrocladus from the Lower Permian Gipshuken Formationon Spitsbergen - implications for palaeobiogeography and palaeoecology. doi: https:/indico.uni-muenster.de/event/4105/book-of-abstracts.pdf. Fulltekst i vitenarkiv Vis sammendrag

  We report the first systematic description of Permian plant macrofossils from the Lower Permian Gipshuken Formation on Spitsbergen, Svalbard, Arctic Norway. Several conifer shoots from a fossil plant horizon in the lower Vengeberget member are assigned to the genus Quadrocladus. The plant-bearing interval occurs within stacked anhydrite–dolomite–marl successions of the Vengeberget member that record a shallow marine to supratidal sabkha system on an extensive carbonate platform in a semi arid climate, characterized by hypersalinity, low taxonomic diversity, and evidence for palaeosol formation and vegetation growth on exposed shoals and platform interiors. The Quadrocladus shoots display pronounced xeromorphic traits, notably very short and narrow leaves, consistent with adaptation to water stress in semi arid, periodically desiccated playa–sabkha settings. Comparison with younger occurrences from the Kungurian Tregiovo flora and Late Permian Angaran and Zechstein successions shows that the Spitsbergen record is so far, both the oldest and the northernmost known occurrence of Quadrocladus. These findings imply a boreal, semi arid origin for this xeromorphic, stress tolerant conifer and provide a key high latitude data point for reconstructing Early Permian vegetation dynamics and the subsequent palaeobiogeographic expansion of Quadrocladus across Pangaea.

• Kürschner, Wolfram Michael (2025). Nieuwe inzichten over paleo-atmosferisch CO2 van het Laat Trias aan de hand van zaadvarens en Ginkgo bladeren. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2024). Modernization of a Late Triassic pCO2 record based on Lepidopteris ottonis and Ginkgoites taeniatus leaves from Germany (a contribution to CO2PIP). Fulltekst i vitenarkiv
• Nakrem, Hans Arne & Kürschner, Wolfram Michael (2024). Et spesielt plantefossil fra Svalbard. Paleobloggen. Fulltekst i vitenarkiv
• Tekin, Kagan; Krystyn, Leopold; Kürschner, Wolfram Michael; Okuyucu, Cengiz; Sayit, Kan & Forel, Marie-Béatrice (2023). Integrated stratigraphy (from radiolarians, conodonts, palynomorphs, ammonoids, ostracods) of the Early Carnian deepening upward sequence (the Huglu Unit) within the tectonic slices/blocks of the Mersin Melange, southern Turkey: biochronologies and paleogeographic implications. Fulltekst i vitenarkiv
• An, Pengcheng; Krystyn, Leopold; Wang, Yongdong & Kürschner, Wolfram Michael (2023). Integrated stratigraphy of Carnian deposits in the Dinaric Alps, Glamoc (SW Bosnia-Hercegovina). Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2022). Discussion of Stomata frequency analysis as a proxy for palaeo-atmospheric CO2 reconstructions. Fulltekst i vitenarkiv
• Sun, Yadong; Richoz, S. & Kürschner, Wolfram Michael (2021). Editorial preface to special issue: Triassic at the dawn of modern world in honour of Prof. Leopold Krystyn. Global and Planetary Change. ISSN 0921-8181. doi: 10.1016/j.gloplacha.2021.103633. Fulltekst i vitenarkiv
• Bang, Emil; Smelror, Morten; Kürschner, Wolfram Michael & Nakrem, Hans Arne (2021). Palynology of Early Cretaceous hydrocarbon seep carbonates from Wollaston Forland, Northeast Greenland – preliminary results. Fulltekst i vitenarkiv
• Zaputlyaeva, Alexandra; Mazzini, Adriano; Blumenberg, M; Scheeder, Georg; Kürschner, Wolfram Michael & Kus, J [Vis alle 8 forfattere av denne artikkelen] (2020). Timing – an underestimated key factor for source rock evaluation, case study from NE Java, Indonesia. Fulltekst i vitenarkiv
• Labes, Alienor; Mazzini, Adriano; Akhmanov, Grigorii G. & Kürschner, Wolfram Michael (2020). Palynology of Holocene Lake Baikal sediments. Fulltekst i vitenarkiv
• Gravendyck, Julia; Bachelier, Julien B.; Kürschner, Wolfram Michael & Herendeen, Patrick S. (2020). (009) A proposal to solve a paradox when neotypifying names of fossil‐taxa. Taxon. ISSN 0040-0262. 69(3), s. 628.–628.. doi: 10.1002/tax.12249. Fulltekst i vitenarkiv
• Zaputlyaeva, Alexandra; Mazzini, Adriano; Blumenberg, Martin; Scheeder, Georg; Kus, Jolanta & Kürschner, Wolfram Michael (2019). Source Rock Maturity and Hydrothermal/Magmatic Activity: The Lusi Eruption Case Study, Ne Java, Indonesia. 29th International Meeting on Organic Geochemistry. doi: 10.3997/2214-4609.201902716. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2019). A review of Late Triassic and Early Jurassic palynology. Fulltekst i vitenarkiv Vis sammendrag

  The Late Triassic is characterized by enhanced rates of biotic turnover in the marine and terrestrial realms culminating in the End-Triassic extinction. Several negative C-isotope anomalies have been reported that indicate coeval pertubations in the carbon cycle. An integrated approach using physical, bio - and chemostratigraphic tools is pivotal to improve correlations between regions across different latitudes and constrain rates of biotic and environmental changes. In this contribution I review palynological data with emphasis on the Carnian and Triassic – Jurassic intervals from different sections in Europe and Scandinavia and discuss their stratigraphic correlation and environmental significance.

• Kürschner, Wolfram Michael; Soelen, Elsbeth Ester van; Rusinovich, Ales & Suprunenko, O. I. (2018). Palynostratigraphy and Carbon Isotope Stratigraphy of the Permian Triassic Strata in the Timan-Pechora basin. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2018). On the Biological Significance of Pollen and Spore Tetrads. Fulltekst i vitenarkiv
• Baranyi, Viktoria & Kürschner, Wolfram Michael (2018). A comparision of the North American and European Carnian and Norian palynofloras. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Soelen, Elsbeth Ester van; Rusinovich, Ales & Suprunenko, Oleg (2018). Palynostratigraphy and Carbon Isotope Stratigraphy of the Permian-Triassic Strata in the Timan-Pechora basin. Fulltekst i vitenarkiv Vis sammendrag

  The Timan–Pechora Basin is a complex of rift basins and a series of foreland basins along the Uralian orogenic front on the east margin of the basin. The Permian-Triassic (PT) strata were studied in 4 cores located alongside an East-West transect from the eastern Barents Sea into the eastern part of the Pechora sea including the Kolguyev Island. 25 sediment samples were analyzed for palynology, palynofacies and C-isotope composition of the bulk sedimentary organic matter. The aim of the present study was to establish a constrained stratigraphic correlation of the Permian/Triassic transition in the Norwegian and Russian Arctic sector as well as the Uralian foreland basin. The Upper Permian – Lower Triassic sediments comprise shallow marine to continental mixed siliciclastic sediments (sand-, silt- and mudstones) that are deposited on a shallow shelf with deltaic complexes to coastal plain environment with fluvial-estuarine sediments. All samples show a C-isotope composition of about -26 to -27 permille. We did not find a negative C isotope excursion which is normally characteristic for the PT boundary interval. Some of the mud-siltstone samples yielded well preserved palynomorph assemblages dominated by taeniate and bisaccate pollen and spores. The maturity of the organic matter is low, TAS 1-2. The palynofacies is dominated by wood remains, cuticle fragments and some degraded amorphous matter characteristic for fluvio-deltaic sediments. The presence of acritarchs indicate a marine influence in a neritic depositional environment. Reduviasporonites and taeniate pollen (Weylandites, Vittatina) are indicative for the PT boundary interval. However, so far spore dominated assemblages, as reported from Greenland, the Barents Sea or Svalbard are absent. Our preliminary data may indicate a sedimentary hiatus at the PT boundary in the Timan-Pechora basin or the absence of PT boundary features are due to a still rather low sampling density in the cores.

• Soelen, Elsbeth Ester van; Peterse, Francien & Kürschner, Wolfram Michael (2017). A compound specific carbon isotope record for the late Permian to Early Triassic. Fulltekst i vitenarkiv Vis sammendrag

  The end Permian biotic crisis is one of the most severe extinction events in the history of the earth. A carbon isotope shift near the Permian-Triassic boundary is an important global stratigraphical tool, showing a negative shift of 5-10‰ over the late Permian extinction phase. However, most records displaying this shift are based bulk carbon isotope values. Since the start of the extinction is characterized in many marine settings by the onset of anoxia, it coincides with a sharp increase in marine derived organic matter. Such a change in palynofacies affects also the δ13CTOC record. Compound, specific isotope analysis (CSIA) can help to improve the δ13C curve and help to estimate the size of the atmospheric carbon-isotope shift, which is thought to result from CO2 release by a large ingenous province (LIP) in Siberia. However, the high maturity of many late Permian sections complicates lipid biomarker work, especially if oil has migrated into the study section. We present data from low mature sediments covering the late Permian to Early Triassic. The sediments were deposited in a shallow marine environment in the Barents Sea and were recovered from the Finnmark plateau by drilling. Long chain n-alkanes (C25-C35) show a strong odd-over-even dominance, and the alkanes likley derive from the leave-waxes of higher terrestrial plants (i.e. trees). In a next step, CSIA on the long chain n-alkanes will help to estimate the magnitude of the change in atmospheric carbon isotope values.

• Soelen, Elsbeth Ester van; Peterse, Francien & Kürschner, Wolfram Michael (2017). A comparison of bulk versus compound specific C-isotope and palynological data from core 7128/12-U-01: implications for the use of C-isotope chemostratigraphic correlation of the Permian-Triassic boundary interval on the Barents shelf. Fulltekst i vitenarkiv
• Soelen, Elsbeth Ester van; Hasic, Edi; Planke, Sverre; Svensen, Henrik; Sleveland, Arve Rein Nes & Midtkandal, Ivar [Vis alle 8 forfattere av denne artikkelen] (2017). Permian-Triassic palynofacies and chemostratigraphy in a core recovered from central Spitsbergen. Fulltekst i vitenarkiv
• Iqbal, Shahid; Wagreich, Michael; Jan, Irfan; Kürschner, Wolfram Michael & Gier, Susanne (2017). Geochemical evidences for palaeoclimatic fluctuations at the Triassic-Jurassic boundary: southwestern margin of the Neotethys in the Salt Range, Pakistan. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2017). Revisiting the stratigraphic correlation of Tr-J boundary interval – new and old concepts. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Iqbal, Shahid; Wagreich, Michael; Jan, Irfan & Gier, Susanne (2017). Palynology and Carbon isotope stratigraphy of the Triassic – Jurassic transition in the Salt Range (Pakistan). Fulltekst i vitenarkiv
• Grundan, Ekaterina; Kürschner, Wolfram Michael & Wout, Krijgsman (2017). Climate variations in the late Miocene – early Pliocene in the Black Sea region (Taman peninsula) inferred from palynological analyses. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2017). Late Triassic Environmental changes inferred from palynological and Carbon isotope studies. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Soelen, Elsbeth Ester van (2016). Permian – Triassic palynology and stratigraphy. Fulltekst i vitenarkiv
• Soelen, Elsbeth Ester van; Planke, Sverre; Svensen, Henrik; Twitchett, Richard; Polozov, Alexander G. & Kürschner, Wolfram Michael (2016). Chemo- and palyno-stratigraphy of the Permian-Triassic transition in the Boreal region. Fulltekst i vitenarkiv
• Soelen, Elsbeth Ester van; Planke, Sverre; Svensen, Henrik; Twitchett, Richard; Polozov, Alexander G. & Kürschner, Wolfram Michael (2016). Chemo- and palyno-stratigraphy of the Permian-Triassic transition in the Boreal region. Geophysical Research Abstracts. ISSN 1029-7006. Fulltekst i vitenarkiv
• Font, Eric; Adatte, Thierry; Planke, Sverre; Svensen, Henrik & Kürschner, Wolfram Michael (2016). Impact, volcanism, global changes, and mass extinction. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 441, s. 1–3. doi: 10.1016/j.palaeo.2015.11.001. Fulltekst i vitenarkiv
• Planke, Sverre; Zuchuat, Valentin; Svensen, Henrik; Hammer, Øyvind; Braathen, Alvar & Silkoset, Petter [Vis alle 27 forfattere av denne artikkelen] (2016). Coring and High-Resolution Imaging of the Permian-Triassic Boundary in Deltadalen, Svalbard. Fulltekst i vitenarkiv
• Mueller, Steven & Kürschner, Wolfram Michael (2016). The Carnian Pluvial Phase in the Boreal. Fulltekst i vitenarkiv
• Soelen, Elsbeth Ester van; Twitchett, Richard & Kürschner, Wolfram Michael (2016). END PERMIAN SALINITY AND OXYGENATION CHANGES IN A SHALLOW MARINE BASIN IN EAST GREENLAND. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Krystyn, Leopold (2016). Integrated stratigraphy of the Carnian biotic crises. Fulltekst i vitenarkiv
• Olsen, Paul; Parker, William; Kürschner, Wolfram Michael & Huber, Peter E. (2016). Implications of the stratigraphic results of the Colorado Plateau Coring Project (CPCP): salt vs. plate tectonics vs. eustasy in the Late Triassic Chinle Formation. Fulltekst i vitenarkiv
• Miller, Charlotte Sarah; Kürschner, Wolfram Michael; Peterse, Francien; Baranyi, Viktoria & Reichart, Gert-Jan (2016). The Carnian (Late Triassic) carbon isotope excursion: new insights from the terrestrial realm. Geophysical Research Abstracts. ISSN 1029-7006. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Krystyn, Leopold (2016). Integrated stratigraphy of the Carnian biotic crises. Geophysical Research Abstracts. ISSN 1029-7006. 18. Fulltekst i vitenarkiv
• Miller, Charlotte Sarah; Kürschner, Wolfram Michael; Peterse, Francien; Baranyi, Viktoria & Reichart, Gert-Jan (2016). The Carnian (Late Triassic) carbon isotope excursion: new insights from the terrestrial realm. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2015). Atmospheric CO2 and climate history in deep time. Fulltekst i vitenarkiv
• Mueller, Steven; Hounslow, Mark W. & Kürschner, Wolfram Michael (2015). Integrated stratigraphy of the Kapp Toscana Group from central Spitsbergen: identification of the Boreal equivalent of the Carnian Pluvial Phase. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Mueller, Steven & Hounslow, Mark W. (2015). Towards a refined Late Triassic palynostratigraphy in the Boreal region: an example from Carnian Kapp Toscana group on Spitsbergen. Fulltekst i vitenarkiv
• Miller, Charlotte Sarah; Fraser, Wesley; Jardine, Phil & Kürschner, Wolfram Michael (2015). Quantifying UV-B flux over the Late Triassic Carnian Pluvial Extinction Event (c. 233–229 Ma). Fulltekst i vitenarkiv
• Font, Eric; Adatte, Thierry; Planke, Sverre; Svensen, Henrik & Kürschner, Wolfram Michael (2015). Impact, volcanism, global changes, and mass extinction. Palaeogeography, Palaeoclimatology, Palaeoecology. ISSN 0031-0182. 441, s. 1–3. doi: 10.1016/j.palaeo.2015.11.001. Fulltekst i vitenarkiv
• Mueller, Steven & Kürschner, Wolfram Michael (2015). Depositional Environments and Integrated Stratigraphy of the Upper Triassic Kapp Toscana Group on Svalbard and the Barents Sea Shelf. Fulltekst i vitenarkiv
• Krystyn, Leopold; Richoz, Sylvain; Maslo, Martin; Kürschner, Wolfram Michael; Gardin, Silvia & Gallet, Yves (2015). Proposal for a candidate GSSP for the base of the Rhaetian stage at Steinbergkogel (Salzkammergut, Austria). Berichte Institutes für Erdwissenschaften Karl-Franzen-Univ. Graz. ISSN 1608-8166. 21, s. 213–213. Fulltekst i vitenarkiv Vis sammendrag

  The Steinbergkogel section near Hallstatt, Salzkammergut, Austria is proposed as candidate GSSP for the Norian-Rhaetian boundary (NRB) with the boundary defined in bed 111 of section A, 2m20 above section base by the FAD of Misikella posthernsteini. This definition follows the boundary recommendation of the NRB Task Force of the Subcommission on Triassic Stratigraphy. The Steinbergkogel exposes a pelagic basin facies of red and gray Middle Norian to Lower Rhaetian Hallstatt Limestone with a rich ammonoid and conodont fauna. Accompanying biostratigraphic boundary markers are the FA of Misikella koessensis, the FA of the ammonoids Paracochloceras suessi and of Sagenites s.str. Despite the overall rare occurrence of Misikella posthernsteini in the early Rhaetian, Bed 111 further shows a distinct conodonts frequency change from Epigondolella to Misikella dominance as a valuable proxy for the boundary. An identical, time-correlative shift in conodont biofacies is seen in the Steinbergkogel quarry sections B and C and in various Tethyan sections from Germany (Berchtesgaden), Austria (Hallstatt, Dachstein, Hernstein), Slovakia (S. Brezova), Turkey (Oyuklu; Mersin), Oman (Musandam; Sumeini, Baid and Al Aqil) and Indonesia (Timor). The FAD of M. posthernsteini occurs 40 cm higher up than the FA of Misikella hernsteini. Just below the FO of Misikella hernsteini is the LO of Metasibirites, a widespread late Norian ammonoid genus and the worldwide disappearance of Monotis (M. salinaria/subcircularis in low palaeolatitudes and M. ochotica group in the Boreal). Very rare coccolith spp were observed below the Norian-Rhaetian boundary. They increase in abundance just above the FAD of Misikella posthernsteini where the first Crucirhabdus minutus was also recorded. Above the FAD of M. posthernsteini is also the FA of the dinoflagellate cyst Rhaetogonyaulax rhaetica, which can be here lithologically controlled, followed by the disappearance of the “Norian” palynomorphs. Between the FA of M. hernsteini and the FAD of M. posthernsteini lies a magnetic polarity reversal, ending a relatively long normal polarity interval, which can be recognized in other Tethyan magnetostratigraphies whereas, unfortunately, a clear correlation with the lacustrine Newark magnetochronology remains ambiguous. The delta13Ccarb record is well preserved and shows no significant variations around the boundary. The Austrian Salzkammergut region fulfills essential requirements for a Rhaetian GSSP: i) A lithologically uniform boundary interval, good exposure conditions in an old abandoned quarry and location on public land in a mountainous forested area in an UNESCO world heritage site assure longtime preservation and accessibility, ii) the area is well known for diverse Norian-Rhaetian low palaeolatitude invertebrate faunas (cephalopods, bivalves, gastropods, brachiopods, reefal organisms) found in different bathymetric and facial environments; iii) knowledge of their temporal and spatial distribution is now well advanced and a high-resolution correlation framework of the relevant pelagic biomarkers (ammonoids, conodonts) linked to abiotic stratigraphic tools such as stable isotopes and magnetostratigraphy has been achieved; iv) the multistratigraphical approach allows a correlation with the geochronologically constrained Pucara Group in northern Peru where the NRB is dated to around 205,5 my, and in the future hopefully with the astrochronologically tuned time scale of the Newark basin.

• Soelen, Elsbeth Ester van; Richard, Twitchett & Kürschner, Wolfram Michael (2015). Palynology of the Permian-Triassic transition in East Greenland. Fulltekst i vitenarkiv
• Soelen, Elsbeth Ester van; Twitchett, Richard & Kürschner, Wolfram Michael (2015). Palyno- and chemo-stratigraphy of the Permian-Triassic transition in the Boreal region. Fulltekst i vitenarkiv
• Planke, Sverre; Twitchett, Richard; Zuchuat, Valentin; Svensen, Henrik; Hammer, Øyvind & Braathen, Alvar [Vis alle 22 forfattere av denne artikkelen] (2015). Coring the Permian-Triassic Boundary in Deltadalen, Svalbard. Fulltekst i vitenarkiv
• Miller, Charlotte Sarah; Fraser, Wesley; Jardine, Phil & Kürschner, Wolfram Michael (2015). Quantifying UV-B flux over the Late Triassic Carnian Pluvial Extinction Event (c. 233–229 Ma). Geophysical Research Abstracts. ISSN 1029-7006. 17. Fulltekst i vitenarkiv
• Krystyn, Leopold; Richoz, Silvain; Maslo, Martin; Kürschner, Wolfram Michael; Gallet, Yves & Gardin, Stephan (2015). Proposal for a candidate GSSP for the base of the Rhaetian stage at Steinbergkogel (Salzkammergut, Austria). Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Müller, Steven & Hounslow, Mark (2015). Triassic palynostratigraphy and environmental history: how to correlate the Early Carnian in the Arctic with the Tethys realm. Fulltekst i vitenarkiv
• Olsen, Paul; Geissman, John; Kent, Dennis; George, Gerehls; Irmis, Randall & Mundil, Roland [Vis alle 13 forfattere av denne artikkelen] (2014). The Colorado Plateau Coring Project (CPCP): A Continuous Cored Record of Triassic Continental Environmental Change in Western North America. Fulltekst i vitenarkiv Vis sammendrag

  The Triassic Period (251.9-201.3 Ma) is bound by two of the Earth’s largest mass extinctions, suffered several giant bolide impacts and eruption of 3 large igneous provinces, and witnessed evolution of the main components of modern tetrapod communities, and yet has sparse geochronological calibration. To bridge this gap, NSF- and ICDP-funded coring of Phase 1 of the CPCP finished in 12/2013 with the recovery of two major cores (1A, 518m and 2B, 253m; 31km apart) from opposites sides of Petrified Forest National Park spanning nearly the entire Triassic sequence (Chinle & Moenkopi fms) with many U-Pb datable levels (1,2,3) and a recoverable paleomagnetic polarity record (4). The cores will provide a U-Pb and paleomagnetic exportable time scale and sedimentary and geochemical proxies with undoubted superposition testing the motivating hypotheses of: 1) the accuracy of orbitally-paced cyclicity of the Newark APTS (5); 2) apparent climate trends as a function of drift through climate belts (6) and atmospheric CO2 (7); 3) the temporal link between the mid-Late Triassic biotic turnover and the ~100 km Manicouagan impact (1); and 4) the delayed ecological dominance of dinosaurs coupled to climate-driven provinciality (1,8). For orientation, the cores were drilled using a azimuth-tracking device, deviated 30° and 15° from vertical to the SE and S, and CT-scanned. The unprecedented sedimentological and stratigraphic detail visible in the CT-scans, and geophysical logs, plus the ~100% recovery promises successful tests of the motivating hypotheses and provide a superbly detailed reference section for this key episode in Earth system history. 1, Irmis+,2011, EPSL 309:258; 2, Ramazani+, 2011, GSA Bull. 123:2142; 3, Ramazani+, 2014, AJS 314:981; 4, Steiner & Lucas, 2000, JGR B 105:25791; 5, Kent & Olsen, 1999, JGR 104(B6):12831-12841; 6, Kent and Tauxe, 2005, Science 307:240–244; 7, Schaller+, 2012, EPSL 323-324:27–39; 8, Kent +, 2014, PNAS 111:7958–7963.

• Geissler, Wolfram; Knies, Jochen; Nielsen, Tove; Gaina, Carmen; Matthiessen, Jens & Damm, Volkmar [Vis alle 24 forfattere av denne artikkelen] (2014). The Opening of the Arctic-Atlantic Gateway: Tectonic, Oceanographic and Climatic Dynamics - an IODP Initiative. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2014). Vegetation and climate change during the Triassic - Jurassic mass extinction - did good genes help plants to survive one of the biggest earth crises? Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Mueller, Steven (2014). Integrated Magneto-, Carbon isotope and quantitative palynostratigraphy of the Upper Triassic Kapp Toscana Group on Spitsbergen, Norway. Fulltekst i vitenarkiv
• Mueller, Steven & Kürschner, Wolfram Michael (2014). Depositional Environments and (Bio-)stratigraphy of the Upper Triassic Kapp Toscana Group on Svalbard and the Barents Sea Shelf. Fulltekst i vitenarkiv
• Mueller, Steven & Kürschner, Wolfram Michael (2014). Depositional Environments and (Bio-)stratigraphy of the Upper Triassic Kapp Toscana Group on Svalbard and the Barents Sea Shelf. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Mueller, Steven (2014). Late Triassic (Carnian) Boreal vegetation and climate history and its relationship with the Wrangellia large igneous province. Geophysical Research Abstracts. ISSN 1029-7006. 16. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Mueller, Steven (2014). Late Triassic (Carnian) Boreal vegetation and climate history and its relationship with the Wrangellia large igneous province. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2014). Classopollis variability in tetrads and pollen size – implications for palaeopolyploidy among early Jurassic Cheirolepidiaceae. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2013). Vegetation history through periods of extreme environmental changes. Fulltekst i vitenarkiv
• Mueller, Steven & Kürschner, Wolfram Michael (2013). Palynofacies and palynology of the Upper Triassic deposits at the Judvalskampen section (central Spitsbergen). Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Batenburg, Sietske & Mander, Luke (2013). Abberant Classopollis pollen reveal evidence for environmental mutagenesis in conifers during the End-Triassic mass extinction. Fulltekst i vitenarkiv
• Mueller, Steven & Kürschner, Wolfram Michael (2013). Palynostratigraphy of Upper Triassic sections of the Kapp Toscana Group on Central Svalbard. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael; Mander, Luke; Mueller, Steven & Ruhl, Micha (2013). Late Triassic palynology in the Alpine and Arctic realm: a review of palynofloral trends and their stratigraphic correlations. Fulltekst i vitenarkiv Vis sammendrag

  The end – Triassic period is characterized by major faunal turnover that culminated in the extinction of about 25% of marine and terrestrial families. Palynological records show a more variable decline in floral diversity but overall pronounced quantitative changes in vegetation composition. Several lines of evidence suggest that the effects of a major flood basalt volcanism in the Central Magmatic Province and associated environmental changes, such as rising CO2 and warming, methane release and ocean acidification, were the causes for this biotic crisis. However, the different scenarios are still controversially discussed. In this contribution we review palynological data from different sections from the Alpine to the Arctic realm and discuss their stratigraphic correlation and environmental significance.

• Michael, Szurlies; Geluk, Mark C.; Wout, Krijgsman; Kürschner, Wolfram Michael & Zeug, Matthias (2012). High-resolution base-level cycles and sand dispersal directions around the Permian-Triassic boundary in Western and Central Europe. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2012). Variation in pollen size and tetrad configuration in Late Triassic Classopollis as a measure of polyploidy in Cheirolepidaceae. Fulltekst i vitenarkiv
• Hincke, Alexandra J.C.; Hunt, John; Kürschner, Wolfram Michael; Lotter, André F. & Wagner-Cremer, Friederike (2012). Stomatal response of Nothofagus fusca (New Zealand red beech) to CO2 availability and nutrient status. Fulltekst i vitenarkiv
• Hincke, Alexandra JC; Kürschner, Wolfram Michael; Lotter, André F.; Tinner, Willy & Kaltenrieder, Petra (2011). Plants in a low CO2 world: validation of botanical proxies for the Pleistocene. Fulltekst i vitenarkiv
• Elkelani, Mohamed; Reichart, Gert Jan; Damsté, Jaap Sinninghe; Smeenk, Zwier; Kürschner, Wolfram Michael & Brinkhuis, Henk [Vis alle 7 forfattere av denne artikkelen] (2011). Palaeoenvironmental change reflected by carbon isotopes and palynology in the Early Silurian of the Tanezzuft Formation, Libya. Fulltekst i vitenarkiv
• Hincke, Alexandra J.C.; Kürschner, Wolfram Michael; Lotter, André F.; Tinner, Willy & Kaltenrieder, Petra (2011). Plants in a low CO2 world: validation of botanical proxies for the Pleistocene. Fulltekst i vitenarkiv
• Schneebeli-Hermann, Elke; Hochuli, Peter A.; Kürschner, Wolfram Michael & Bucher, Hugo (2011). Terrestrial ecosystems during and following the end-Permian mass extinction - or from spore spike to spore spike. Fulltekst i vitenarkiv
• Schneebeli-Hermann, Elke; Kürschner, Wolfram Michael; Hochuli, Peter A.; Goudemand, Nicolas; Ware, David & Bucher, Hugo [Vis alle 7 forfattere av denne artikkelen] (2011). Permian-Triassic palaeoenvironment inferred from palynofacies data of Amb, Salt Range, Pakistan. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2011). Peculiarities of Permian – Triassic palynological records. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael (2011). Plants in a low CO2 world – an integrated study of plant growth in low CO2 experiments and late glacial fossil remains. Fulltekst i vitenarkiv
• Kürschner, Wolfram Michael & Mueller, Steven (2015). Stratigraphy and depositional environments of the Boreal and Tethyan Early Carnian (Triassic) - Evidence by palynology and geochemistry. Akademika forlag. Fulltekst i vitenarkiv

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