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Early Jurassic palaeoenvironments and palaeoclimates, based on chemostratigraphy, have been extensively studied for the northern Tethyan margin. For the first time, high-resolution chemostratigraphy for the entire Pliensbachian is proposed for the African Tethyan margin (Morocco), and compared with new sections from the European Tethyan margin (France). Precise ammonite determinations, completed by calcareous nannofossil distribution, provide an accurate biostratigraphic framework from the Upper Sinemurian to the Upper Pliensbachian. Bulk inorganic carbon (d13Ccarb) and organic carbon (d13Corg) isotope signals are used to characterise and compare carbon-cycle trends in the Central High Atlas Basin (Amellago-Ikis section, Morocco), the Paris Basin (Montcornet borehole, France), and the Subalpine Basin (Serre-Ponçon section, France). Comparison of this new dataset with previously published geochemical data from European basins confirms the existence of five distinct carbon-isotope events, synchronous at the scale of the NW Tethyan Realm: (1) a clear –2‰ negative excursion of d13Ccarb and d13Corg, corresponding to the Sinemurian–Pliensbachian Boundary Event (SPBE), probably associated with a massive release of light carbon by volcanism and hydrothermalism during the breakup of Pangea; (2) a positive excursion (+1 to +1.5‰) in the Valdani and Luridum subzones (Ibex Zone), reflecting increased organic matter storage under warm climate conditions; (3) a broadly negative event from the Davoei Zone to the lower part of the Margaritatus Zone, associated with major oceanographic reorganisation in a transgressive context, and possible enhanced hydrothermalism related to the opening of the Hispanic corridor; (4) a positive carbon excursion (+2‰) during the Subnodosus and Gibbosus subzones (Margaritatus Zone), corresponding to the Late Pliensbachian Event (LPE), associated with organic matter storage; (5) an end-Margaritatus–Spinatum negative excursion, associated with sea-level fall, probably driven by glacio-eustasy. This new high-resolution carbon-isotope dataset highlights the synchroneity of carbon-cycle trends throughout the NW Tethyan Realm. Several major isotopic events, prior to those of the Toarcian, must therefore have occurred at a supra-regional to global scale during the Pliensbachian, involving significant internal and external geodynamic mechanisms.

A new record of carbon isotopes, nannofossil biostratigraphy, gamma-ray and Fe content variations is presented for the upper Campanian of the Adda-3 core, Danish Central Graben, North Sea. The studied interval provides a revision of previously assigned late Coniacian to early Santonian ages. New biostratigraphic data indicate a late Campanian age for the 60m thick studied interval. The Late Campanian Event (LCE) iswell recorded by a 1.5‰ negative excursion in the bulk δ13C, along with two stepwise pre-excursion negative shifts (defining the pre-LCE). The amplitude of the LCE appears higher in the North Sea than in other areas as seen from the correlation to Germany, the UK and France. This correlation allows identification of a new 0.4‰ negative excursion (defined as the conica event). Fe and gamma-ray variations are used to calibrate the record with cyclostratigraphy. Fourteen 405 kyr cycles identified in the upper Campanian of Adda-3 can be correlated to North Germany. The compilation of previous results from North Germany and correlation to Adda-3 shows that the Boreal upper Campanian spans a total of 17 cycles each of 405 kyr; that is, 6.885 myr. The duration of the LCE is estimated to be c. 1 myr at Adda-3 and in North Germany. [ABSTRACT FROM AUTHOR]

New stratigraphic (calcareous nannofossils and carbon isotope) and sedimentological results from the upper Campanian – Maastrichtian of the Stevns-2 core, Denmark, allow for regional correlations and building of a solid age-model with the definition of 17 stratigraphic tie-points in the Danish Basin. Based on the correlation of four different sites to this age-model, the reliability of 26 calcareous nannofossil biohorizons is assessed and points to a revision of the standard upper Campanian – Maastrichtian nannofossil biozonation in the Boreal Realm. A modified calcareous nannofossil zonation is presented for the Danish Basin, calibrated in age and correlated to high-resolution carbon isotope stratigraphy. Common, regional changes in sediment accumulation rates highlight trends that appear linked to climatic conditions.

Calcareous nannofossil biostratigraphy and stable isotope stratigraphy have been investigated in the Shahneshin section of the Gurpi Formation from the Zagros Basin (Iran). The results show that the Gurpi Formation spans the late early Coniacian to late Thanetian. The age-model shows that the Shahneshin section spans the Coniacian to mid-Campanian with a good continuity whereas condensation is highlighted in the late Campanian, across the Campanian/Maastrichtian boundary and in the late Maastrichtian. Extreme condensation is recorded after the Cretaceous-Paleogene boundary with the complete absence of the Danian, and the Selandian and lower Thanetian being comprised in only 6 m at the top of the Gurpi Formation. Correlation of the carbon-isotope profile with other reference curves allows the recognition of several Late Cretaceous excursions at the Shahneshin section such as the Beeding, White Fall, Kingsdown, Michel Dean, Haven Brow, Horseshoe Bay, Buckle, Hawks Brow, Santonian/Campanian boundary (SCBE) and Campanian/Maastrichtian boundary (CMBE) events. Correlation to a recently proposed global δ13C stack for the Late Cretaceous points to a major mismatch of this compilation with magnetostratigraphy in the Santonian – early Campanian interval. The δ13C correlation, supported by calcareous nannofossil biostratigraphy, brings insights into: (1) the position of the Coniacian/Santonian, Santonian/Campanian and Campanian/Maastrichtian boundaries with respect to carbon-isotope stratigraphy and calcareous nannofossil bio-horizons, and (2) their correlation between the Tethyan and Boreal realms.

The rhythmically bedded limestone-marl alternations in the coastal cliffs of Sopelana and Zumaia in the Basque country, northern Spain, permit testing and refining of existing Maastrichtian chronologies (latest Cretaceous). The recently established astronomical time scale for the late Maastrichtian at Zumaia is extended into C31n with the integrated stratigraphy of the Sopelana section. The cyclic alternations of hemipelagic limestones and marls at Sopelana show a strong influence of eccentricity-modulated precession. Together, the Zumaia and Sopelana sections span almost the entire Maastrichtian, and encompass thirteen 405 kyr cycles spanning a total duration of 5.3 myr. From the Cretaceous-Paleogene (K-Pg) boundary downwards, 405 kyr minima in the lithological, magnetic susceptibility and reflectance data records are tuned to successive 405 kyr minima in the new La2011 eccentricity solution. Assuming a K-Pg boundary age of 65.97 Ma, we present orbitally tuned ages of biostratigraphic and magnetostratigraphic events. Whereas the bases of Chrons C29r and C30n were reliably established at Zumaia and are in good agreement with previous studies, new data from Sopelana provide a refinement of the basal age of Chron C31r. Additional planktonic foraminifera and calcareous nannoplankton data from Zumaia, and new calcareous nannoplankton data from Sopelana, allow for worldwide correlation of the cyclostratigraphy of the Basque country. [ABSTRACT FROM AUTHOR]

The current study presents new bed‐by‐bed brachiopod δ13C and δ18O records from Öland, Sweden, which together with previously published data from the East Baltic region, constitutes a high‐resolution paired brachiopod and bulk rock carbon and oxygen isotope archive through the Lower to Upper Ordovician successions of Baltoscandia. This new data set refines the temporal control on the global Ordovician δ18O‐trend considerably, improving paleoenvironmental reconstructions through the main phase of the Great Ordovician Biodiversification Event (GOBE). The new brachiopod carbon and oxygen isotope records from Öland display strong similarity with the East Baltic records, elucidating the regional consistency as well as global correlation utility of the ensuing composite Baltoscandian Lower to Middle Ordovician carbon and oxygen isotope record. The carbon isotope record from Öland indicates that the widely reported Middle Ordovician carbon cycle perturbation—MDICE (Mid‐Darriwilian Carbon Isotope Excursion)—is recorded in both brachiopods and bulk carbonates. The oxygen isotope record reveals a long‐term Lower to Upper Ordovician trend of increasingly heavier brachiopod δ18O values, with a pronounced increase during the Middle Ordovician Darriwilian Stage. We interpret this trend as dominantly reflecting a paleotemperature signal indicating progressively cooler Early to Middle Ordovician climate with glacio‐eustasy. Our Baltic δ18O values are therefore consistent with postulations that the biotic radiations during the GOBE and climatic cooling during the Darriwilian were strongly linked. Oxygen isotope values obtained from fossil brachiopod shells have traditionally been used as a faithful paleoclimatic proxy to shed light on temperature trends in ancient oceans. However, because brachiopod shells are susceptible to diagenetic overprint after burial, secular oxygen isotope trends derived from these fossils are often questioned—notably the farther one goes back in geological time. This study presents temporally well‐resolved oxygen isotope data from Lower–lower Upper Ordovician sedimentary rocks of Öland, Sweden, tied precisely to conodont biostratigraphy on the bed‐by‐bed scale. This interval is important in Earth history as it brackets the greatest marine biodiversification event known in the fossil record and coincides with a global climatic cooling phase (determined based on proxies other than oxygen isotopes). The current study therefore provides an excellent test of the spatial and temporal consistency of the secular Ordovician oxygen isotope trend. We find that although our data is probably affected by diagenetic modification, primary paleoclimatic signals are preserved. Furthermore, as current global Ordovician oxygen isotope records lack sufficient resolution because they comprise data from geographically widely distributed low‐paleolatitude localities, our new high‐resolution data set from one mid‐paleolatitude region, provides significant temporal insights that considerably improves our understanding of the Ordovician climate. New paired Baltic carbonate data set improves Ordovician 18O‐ and 13C‐recordThe new data supports a Middle Ordovician sea surface temperature coolingRegional/intra‐basinal consistency of oxygen isotope trends indicate primary nature of paleoenvironmental changes New paired Baltic carbonate data set improves Ordovician 18O‐ and 13C‐record The new data supports a Middle Ordovician sea surface temperature cooling Regional/intra‐basinal consistency of oxygen isotope trends indicate primary nature of paleoenvironmental changes

A new bio-chronostratigraphic framework is presented for the upper Campanian - Maastrichtian pelagic sediments of the Gubbio area (Bottaccione and Contessa Highway sections, Italy). New planktonic foraminiferal (FO of P. hantkeninoides), calcareous nannofossil (FO of M. prinsii, base acme of M. murus) and magnetostratigraphic data are provided and integrated to construct an age-depth curve based on the recent astronomical calibration of the late Campanian - Maastrichtian magnetic polarity time scale (Husson, D., Galbrun, B., Laskar, J., Hinnov, L. A., Thibault, N., Gardin, S., Locklair, R. E., 2011. Astronomical calibration of the Maastrichtian, Late Cretaceous. Earth and Planetary Science Letters 305, 328-340). All bio-horizons recorded in both sections fall on or are very close to the Line of Correlation (LOC), which testifies to the reliability of biochronologic studies in the Umbria-Marche basin. The proposed age model allows to estimate the sedimentation rates and the ages of calcareous nannofossil and planktonic foraminiferal bio-horizons in both sections. Also, it provides an excellent late Campanian - Maastrichtian reference for sections in the Umbria-Marche area and the entire Tethys. Due to the presence of a ∼425 kyr-long hiatus in Chron C31n of the Bottaccione section, the Contessa Highway section constitutes a more complete late Campanian - Maastrichtian reference for bio-magnetochronology in the Tethyan realm.

Abstract:Event history surveys provide a means to analyse large numbers of complete individual occupational trajectories. A variety of statistical methods have been developed to measure the time spent in a give state as a function of individual characteristics. Until the 1990s, exploratory data analysis to describe the full complexity of trajectories was rarely mentioned in the literature. Qualitative harmonic analysis and optimal matching are two exploratory methods that can be used to build typologies of complex individual trajectories that take account of both the sequence and the duration of events. They are used here to classify the working careers of male respondents of the Biographies et entouragesurvey (INED, 2001), with the aim of comparing the respective advantages of each technique.Abstract:Les enquêtes biographiques permettent d'analyser un grand nombre de carrières professionnelles individuelles dans leur intégralité. Diverses méthodes statistiques ont été développées pour mesurer les durées de séjour dans un état considéré en fonction de caractéristiques individuelles. Jusqu'aux années 1990, le traitement exploratoire des données avec l'objectif de décrire les parcours dans leur complexité n'avait fait l'objet que de peu d'attention dans la littérature. L'analyse harmonique qualitative et les méthodes d'appariement optimal sont deux méthodes exploratoires qui permettent de construire des typologies de parcours individuels complexes en prenant en compte la séquence des événements et leur durée. On les utilise ici pour reconstituer des typologies des carrières professionnelles des hommes interrogés lors de l'enquête Biographies et entourage(Ined, 2001) afin de comparer l'intérêt respectif de chacune de ces techniques.Abstract:Las encuestas biográficas permiten analizar un gran número de carreras profesionales individuales en su totalidad. Se han desarrollado diversos métodos estadísticos para medir las duraciones de las estancia en un estado considerado en función de características individuales. Hasta los años 1990, el tratamiento exploratorio de los datos con el objetivo de describir los recorridos en su complejidad había sido objeto de poca atención en la literatura. El análisis armónico cualitativo y los métodos de emparejamiento óptimo son dos métodos exploratorios que permiten elaborar tipologías de recorridos individuales complejos tomando en cuenta la secuencia de los acontecimientos y su duración. Aquí se les utiliza para reconstituir tipologías de las carreras profesionales de los hombres interrogados en la encuesta Biographies et entourage (Ined, 2001), con la finalidad de comparar el interés respectivo de cada una de estas técnicas.

A detailed biostratigraphic, chemostratigraphic, and chronostratigraphic study was carried out in the South‐Western margin of the Neo‐Tethys ocean (Tunisia) covering the Eocene‐Oligocene interval to report potential paleoenvironmental and paleoclimatic changes associated with the growth of the Antarctic ice sheet (AIS). The studied section consists of marls and limestones extending from the Helicosphaera compactanannofossil Zone (CNE21) to the Reticulofenestra umbilicusZone (CNO2). The Bc of Clausicoccus subdistichuscoincides in northeastern Tunisia with the extinction of hantkeninids and is thus used here to define the Eocene/Oligocene boundary (EOB) at 34.03 Ma. Calcareous nannofossil assemblages suggest a significant change from oligotrophic/warm surface waters during the late Eocene to eutrophic/cool waters during the early Oligocene. The observed changes in trophic conditions are synchronous with a shallowing trend testified by an increase in nearshore species and enhanced terrigenous input. Major environmental changes occurred at the EOB and across glaciation event Oi‐1a whereas we record a poor imprint of glaciation event Oi‐1. Three orbital configurations have been distinguished: (1) The late Eocene is characterized by a prominent 405‐kyr cycle and a weak obliquity component; (2) the onset of cooling at 34.35 Ma coincides with the rosette‐shaped discoasterextinction and is reflected by a shift toward enhanced obliquity and short‐eccentricity cycles. The installation of a fully developed AIS (event Oi‐1a, 32.75 Ma) shows the most pronounced obliquity imprint reflecting an increased influence of high‐latitude climate processes; (3) after 31.75 Ma, the obliquity decreases in coincidence with the return to a dominant long‐eccentricity cycle. The Eocene/Oligocene transition corresponds to one of the most important climatic shifts in the Cenozoic. This paleoclimatic shift from the greenhouse of the late Eocene to the icehouse regime in the early Oligocene triggered changes in the paleoenvironmental conditions of the Neo‐Tethyan area. We used calcareous nannofossil assemblages, carbon isotopes, elemental data (X‐ray fluorescence), and spectral analysis applied on magnetic susceptibility to report the possible effects of ice volume changes associated with the Antarctic glaciation on the Southern Neo‐Tethyan region and on the expression of Milankovitch cycles at low latitudes. We observe a change in the calcareous nannofossil assemblages that suggests a transition from low‐nutrient/warm‐water conditions to more heterotrophic/cooler conditions across the Eocene/Oligocene interval associated with the shift from a dominant 405‐kyr long‐eccentricity cycles to a prevalent obliquity and short‐eccentricity forcing. However, the situation shifted again at 31.75 Myr, with the return of dominant long‐eccentricity cycles. High phytoplankton productivity across the EOT of the Southern Neo‐Tethys (Tunisia)Astronomical calibration of the Tunisian record and power variations in the expression of distinct orbital components across the EOTMajor changes in trophic conditions and sediment composition at the EOB and across Oi‐1a but minor changes across the main Oi‐1 glaciation

The article focuses on the initiative made by INTERSPORT France to double its exclusive brands business turnover in four years. It states that INTERSPORT has implemented a product lifecycle management (PLM) technology from Centric Software Inc. to respond to its lack off technological capabilities necessary to achieve its growth targets. Furthermore, INTERSPORT business unit manager Nicolas Thibault says that the company's implementation of the PLM has improved its product development efforts.