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.

Abstract. 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.

The generally arid Late Triassic climate was interrupted by a wet phase during the mid Carnian termed Carnian Pluvial Episode (CPE). Quantitative palynological data from the Mercia Mudstone Group in the Wessex Basin (UK), reveals vegetation changes and palaeoclimate trends. Palynostratigraphy and bulk organic carbon isotope data enable 9 Laxitexella multireticulata within the Lincombe Member in the coastal sections which is indicative of the early Carnian L. mucroreticulata Zone (Kozur & Weems 2010). This species is common in the early Carnian 'Estheria Beds' (in the upper Grabfeld Formation in Germany), but is also reported from the Schilfsandstein in Germany. Hounslow et al. (2002) suggested that the Ladinian-Carnian boundary may be in the upper part of the Sidmouth Mudstone Formation and the Carnian-Norian boundary near the boundary between the DMF and overlying Branscombe Mudstone Formation, however, this was based on hitherto unpublished magnetostratigraphic data. The DMF crops out along coastal cliffs between Higher Dunscombe Cliff and Strangman`s Cove and has a wide distribution in the sub-surface of the Wessex Basin (Gallois & Porter 2006; Porter & Gallois 2008) (Fig. 1). The DMF was cored in two boreholes Wiscombe Park 1 and 2 (WP-1 and 2) about 5 km north of the coastal outcrop (Porter & Gallois 2008) (Fig. 1). Further north in Somerset, several lenticular sandstone units of the Arden Sandstone Fm can be found around Taunton, North Curry and Sutton Mallet areas (Fig. 1), similar to the Lincombe Member of the Dunscombe Mudstone Fm. However, the stratigraphic correlation of these arenaceous units remains uncertain (Gallois 2003; Gallois & Porter 2006). On lithostratigraphical and palaeoenvironmental grounds, Howard et al. (2008) argued that the sandstone bodies in Somerset are contemporaneous with the Lincombe Member, but Gallois (2001) suggested they might occur in a higher stratigraphic position within the DMF compared to the Lincombe Member.

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The Danube Basin is situated between the Eastern Alps, Western Carpathians and Transdanubian mountain ranges and represents a classic petroleum prospection site. The basin fill is known from many 2D reflection seismic lines and deep wells with measured e-logs which provided a good opportunity for theories about its evolution. New analyses of deep wells situated in the Danube Basin northeastern margin allowed us to refine stratigraphy and to interpret various depositional systems. This also allowed us to outline changes in provenance of sediment during the Cenozoic. The performed interpretation of the Palaeogene and Neogene depositional systems also confirmed the Oligocene-Early Miocene exhumation of the basin pre-Neogene basement. Opening and development of the Middle to Late Miocene basin depocentres above the boundary between the Western Carpathians and Northern Pannonian domain was recognized. Our analysis contributed to a better understanding of the Hurbanovo-Di€ osjen} o fault which acts as an inherited weakness zone along the boundary of two crustal fragments with different provenance. We document various basin types stacked one on another (retro-arc, back-arc and extensional hinterland basin). The analysis of sediment sources reveals intricate geodynamic processes during the Eastern Alpine-Western Carpathian orogenic system collision with European platform (formation of ALCAPA microplate) and its successive tectonics escape during the Pannonian Basin System origination.

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, Patina sporites spp., and Froelichsporites traversei are probable indicators of environmental stress, such as increased aridity, perturbations of atmospheric pCO 2 , 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.

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This paper presents the results of a mineralogical, petrographic and palynological study of selected Pannonian calcareous marl and sandstone samples penetrated by the Hódmezővásárhely-I (Hód-I) well, Endrőd Formation (Tótkomlós Member, cores 35 and 40, 5167.0-5183.0 m and 5468.0-5486.0 m, respectively); this formation is part of the Makó Trough of the Pannonian Basin, SE Hungary. The studied sections comprise mixed carbonate-siliciclastic rocks with abundant silt-to sand-sized angular grains such as monocrystalline and polycrystalline quartz, muscovite, biotite, chlorite, carbonate and metamorphic rock fragments. This polymictic and immature clast composition reflects the importance of local provenance, suggesting that intrabasinal structural highs represent additional source areas to the basin. Palynological analysis was carried out on selected core segments of the well in order to provide a biostratigraphic framework and palaeoenvironmental interpretation for the studied interval. In the investigated samples two biozones were distinguished: the Spiniferites bentorii oblongus Zone and the Spiniferites paradoxus Zone. The successive changes of the dinocyst assemblages reflect changes in the distance from the shoreline or the terrestrial input from the margin of the Makó Trough. The older assemblage indicates a more proximal setting in relation to the shoreline and/or a higher terrestrial input; the younger dinocyst assemblage -with a more open-water taxa point in relation to a greater distance from the shoreline -represents an increase in the water level, and/or decreased terrestrial input. The predominance of membranous dinocysts in this assemblage indicates a fluctuation in the lake surface salinity, or possibly a shift to a holoplanktonic lifestyle due to periodical oxygen depletion in the water column. The assemblages of both zones demonstrate their regional distribution throughout the whole Pannonian Basin and therefore they can be used to document regional scale trends in phytoplankton communities, as well as implying the communication of water bodies. The colour and preservation of the palynomorphs suggests significant burial heating and the high maturity of the sedimentary organic matter. In the studied samples a series of paragenetic events have been identified using petrographic methods. Early diagenesis was generally represented by cementation (i.e. of framboidal pyrite and carbonates with variable iron content) and weak mechanical compaction. On the other hand, late diagenesis involved pressure solution (chemical compaction), cementation (late pyrite) and, occasionally, dolomite replacement and mineral transformation (smectite to illite) processes. It is noteworthy that in these two core sections neither significant macroporosity nor microporosity were observed, this being due to pervasive cementation.Keywords: Pannonian, endemic, dinocysts, Spiniferites, diagenesis, paragenetic sequence ÖsszefoglalásMunkánkban a Hódmezővásárhely-I fúrás 35. és 40. magfúrási szakaszaiból (5167,0-5183,0 m, ill...