Abstract A Julian/Tuvalian (=Lower/Upper Carnian) substage boundary within the Kasımlar Formation, recently detected at Aşağiyaylabel (Taurus Mountains, Turkey) by facies analyses and biostratigraphic ammonoid investigations, was additionally detected by magnetic susceptibility (MS) and radiometry data. The Aşağiyaylabel sequence, a key section concerning environmental changes during Early to Late Carnian time, represents a deepening sequence from platform carbonates to pelagic limestones and marls. The Julian/Tuvalian boundary strata can be correlated over wide areas due to a positive shift in MS values from 11–105×10 −6 SI (range AS I, KA IV) at the Lower Carnian sediments to 62–458×10 −6 SI (range AS I, KA IV) at the Upper Carnian sediments as well as in radiometry values from 21.35–83.27 nGy h −1 (range AS I, KA IV) at the Lower Carnian sediments to 38.43–130.24 nGy h −1 (range AS I, KA IV) at the Upper Carnian sediments. A second, smaller positive shift in MS occurs at the transition from shallow-water carbonates of the Kartoz Formation (−11 to 71×10 −6 SI; range AS I–KA II) into deeper-water carbonates from the base of the Kasımlar Formation (3–108×10 −6 SI; range AS I–KA II). This study presents the first MS and radiometry data from Lower to Upper Carnian sediments. They reliably reflect lithological changes and display a direct function of enhanced terrigenous input into marine sediment systems, most probably caused by variations in climatic conditions.

Abstract A number of 3 rd -order depositional sequences have been observed in the Southern Alps, far more than previously known: of these, 6 develop principally in the Scythian, 4 in the Anisian, 3 in the Ladinian, 4 in the Carnian, at least 2 in the Norian and finally 2 in the Rhaetian. Lower Anisian to Lower Carnian depositional sequences are best dated by ammonoids, while in the Scythian ammonoids and conodonts are scanty. In the Upper Carnian, Norian and Rhaetian deposits of the Southern Alps, very rare ammonoids and conodonts are available. Therefore Scythian, Upper Carnian, Norian and Rhaetian depositional sequences have been defined on the basis of stratal patterns and the evolution of facies, being their chronostratigraphical position inferred from sections elsewhere in the world. The contemporaneous analysis of platforms and basins and of carbonate, mixed and siliciclastic deposits has made a good comprehension of facies migration possible. This approach was crucial in the definition of 3 rd -order depositional sequences. Moreover, on the basis of the previously defined 3 rd -order sequences and systems tracts, a number of 2 nd -order transgressive/regressive cycles have been pointed out. The sequence stratigraphic analysis compared with the tectonic history allowed the definition of the different phases of the basin evolution.

Abstract Lead and zinc ores of the Alpine Triassic occur mainly within shallow water sediments of lower Carnian age; these sequences underwent emersion periods and were affected by weathering and meteoric karstification (Lagny, 1975; Bechstadt, 1975a, b, 1979; Assereto et al, 1976). The Bleiberg-Kreuth mineralization within the Wetterstein limestone is controlled by at least four geologic factors: (1) it occurs on lagoonal platforms, situated some distance from the mainland to the north, which might have been the original source of the metal; (2) on these platforms it is localized within areas where an extensive cavity network had been formed by karstic weathering; (3) the mineralization is bound to areas close to or with peritidal cyclic and evaporitic sedimentation (“special facies” of Schneider, 1964); and (4) it occurs below sealing shales (Raibl beds). Only the subaerial exposure facies is described in more detail, whereas the conflicting theories concerning lead-zinc mineralization are mentioned only briefly (Figs. 1,2).