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The compositional variation of calciturbidites (Pedata/Pötschen Formation), deposited adjacent to the Dachstein Formation carbonate platform in the Triassic Hallstatt Basin, was analysed using detailed field measurements and point‐counting of thin sections. The 35 m long section is located in the Northern Calcareous Alps of Austria. Six point‐count groups were distinguished separating basinal from platform‐derived input. Summary statistics, cluster and correspondence analysis of the point‐count data reveals a close relationship between the biota present on the Dachstein carbonate platform and the calciturbidite composition. The variations in turbidite composition are attributed to fluctuations in sea level and resulting flooding and exposure of the platform, which alternately created and destroyed shallow‐water habitats on the platform top.

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A detailed magnetostratigraphic investigation of the Agost section (Spain) containing the Cretaceous-Tertiary (K/T) boundary is reported. Thermal demagnetization--contrary to alternating field demagnetization--succeeds in revealing the polarity of the characteristic remanent magnetization, although an overlap in blocking temperature spectrum exists with a normal polarity, secondary magnetization component. The K/T boundary occurs at two-thirds from the base of a reversed polarity zone and by comparison with earlier results [1] this polarity zone is correlated to chron C29r.Linear regression of sedimentation rates in other sections with an established magnetostratigraphy and containing the K/T boundary yields an age of 66.45 Ma for this boundary. On the basis of this age and the magnetic reversal ages of the Berggren et al. [13]

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