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extinction boundary occurred at the Tenuicostatum–Serpentinumtransition, and that the organic-richfacies linked to the Oceanic AnoxicEvent and the associated negative δ 13 C excursionare diachronous.From a latest Pliensbachian cooling interval, afirst increment of seawater temperature averagingabout 4.5 °C, started around the Pliensbachian–Toarcianboundary and developed duringthe earliest Toarcian Tenuicostatum Biochron,marking the beginning of the main extinctioninterval. From the Tenuicostatum–Serpentinumtransition up to the Bifrons Biochron, a rise inseawater temperature averaging 5.7 °C to 7.8 °Cwas recorded. This warming interval, whichstarted rapidly and which seems to be synchronousat least in Western Europe, is consideredone of the main factors responsible for mass extinction.For some authors this rapid warmingwas probably due to a massive injection ofgreenhouse gases into the atmosphere, but itdoes not seem to be recorded in belemnite calcite,and the origin of these possible gases islargely debated in the literature.Additional isotope excursions were found in thestudied sections in Spain during the Middle andLate Toarcian. A negative δ 13 C bel excursion hasbeen recorded at the latest Bifrons Biochron.Above this shift, the Illustris–Vitiosa subzonesthermal peak, which represents a 2–3 °C ΔT,could be linked to one of the tectonomagmaticactivity peaks recorded in the Karoo Basin. Arenewal in the ammonite and brachipod faunascoincident with this climatic change has beenrecognized in NW Europe and Western Tethys.An interesting thermal peak has also been detectedin belemnites of the Insigne Subzone. ΔTis in the order of 3 °C, and in both sections thethermal peak is included into a δ 13 C bel negativeexcursion of about − 1.5‰. Relative synchronywith the new age for the Karoo main magmaticactivity (178–180 Ma) indicates that the δ 13 Cnegative anomaly and the warming intervalcould be caused by the release of volcanogenicgreenhouse gases. At this short interval, noteworthychanges in the abundance and diversityof the recorded assemblages in several faunalgroups of NW Europe and Tethys are observed.The uppermost Levesquei Subzone thermal peakhas only been recognized in the deposits of thesection located in Central Spain and coincideswith a positive δ 13 C excursion.2008040549“ 突 尼 斯 山 脊 ” 里 阿 斯 统 - 道 格 统 过 渡 。 新 的 地层 数 据 和 特 提 斯 扩 张 到 上 土 阿 辛 阶 = TheLias–Dogger transition in the ‘Tunisian ridge’.New stratigraphical data and Tethyan distensionup to the Upper Toarcian. ( 法 文 ). Sekatni N;Fauré P; Alouani R; Zargouni F. Comptes RendusPalevol, 2008, 7(4): 185-194In the Jebel Bou Kornine of Hammam Lif(northern Tunisia), the transition between Liasand Dogger is located in a carbonate formationthat is approximately 150 m thick (Kef El OrmaFormation). Based on ammonite faunas, its agecan be determined as Upper Toarcian (AalensisZone) up to Lower Bajocian (Propinquans Zone).Four successive conglomeratic units are recognizedin this formation. The two earlier ones aresituated in the Uppermost Toarcian (AalensisZone, Lugdunensis Subzone), while the later twoare in the Opalinum Zone of the Lower Aalenian(Opalinum and Comptum Subzones). These deposits,which associate carbonate-bearing conglomerateswith laminated/slumped calcarenites,result from a gravitational flow on a palaeoslopeinduced by extensive palaeofaults. They testifyto a tectonic instability during the Upper Toarcian,causing the formation of two distinct palaeostructuralunits: the ‘Tunisian trough’ andthe ‘Tunisian ridge’ carbonated platform, bothbelonging to the Maghrebian passive margin ofthe Tethys. We must insist on the part played, assoon as the Upper Toarcian, by the polyphasedtilted-blocks tectonics on the deposition of thedifferent conglomeratic units of the Bou KornineJebel.2008040550西 环 比 利 牛 斯 域 坎 潘 阶 - 马 斯 特 里 赫 特 阶 有 孔虫 Radotruncana calcarata,Gilianelles 和 其 他微 疑 问 化 石 生 物 地 层 = Biostratigraphy ofRadotruncana calcarata (foraminifera), gilianelles,and other microproblematica of theCampanian–Maastrichtian of the westerncircum-Pyrenean domain. ( 法 文 ). Odin G S.Comptes Rendus Palevol, 2008, 7(4): 195-203Microproblematica from the Campanian–Maastrichtian boundary stratotype (Tercis,France) include the continuously evolving genusAturella, short-living taxa, and widely distributedtaxa. The same is true in the immediate vicinityas well as in the southern Pyrénées,100 km apart. These newly established microfossilsallow the most precise regional biostratigraphicalcorrelations. Amongst contemporaneousforaminifera, Radotruncana calcarata wascollected from seven sections from the platformand flysch facies where it was formerly unknownor poorly known. Regionally, this foraminiferis the most precise foraminiferalmarker of the end of the Cretaceous, as it wasalready elsewhere in the world. Absent from theflysch facies, the microproblematica are restrictedto the pithonellid-rich platform facies.2008040551167