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The Cellon section, located in the Carnic Alps, is a reference section for the Silurian of the world. The conodont association of the section is revised according to the most recent taxonomy and the biostratigraphy updated in the basis of the recently published zonation schemes. Seventy taxa (species and subspecies) belonging to 23 genera have been identified, allowing the discrimination of fifteen biozones from the upper Llandovery to the end of the Pridoli. However, some of the uppermost Llandovery and Wenlock biozones, corresponding to black shale intervals, have not been documented

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We present the first reconstruction of the micrometeorite flux to Earth in the Silurian Period. We searched 321 kg of condensed, marine limestone from the Late Silurian Cellon section, southern Austria, for refractory chrome‐spinel grains from micrometeorites that fell on the ancient sea floor. A total of 155 extraterrestrial spinel grains (10 grains >63 μm, and 145 in the 32–63 μm fraction) were recovered. For comparison, we searched 102 kg of similar limestone from the mid‐Ordovician Komstad Formation in southern Sweden. This limestone formed within ~1 Ma after the breakup of the L chondrite parent body (LCPB) in the asteroid belt. In the sample we found 444 extraterrestrial spinel grains in the >63 μm fraction, and estimate a content of at least 7000 such grains in the 32–63 μm fraction. Our results show that in the late Silurian, ~40 Ma after the LCPB, the flux of ordinary equilibrated chondrites has decreased by two orders of magnitude, almost down to background levels. Among the ordinary chondrites, the dominance of L‐chondritic micrometeorites has waned off significantly, from >99% in the post‐LCPB mid‐Ordovician to ~60% in the Late Silurian, with ~30% H‐, and ~10% LL‐chondritic grains. In the Late Silurian, primitive achondrite abundances are similar to today's value, contrasting to the much higher abundances observed in pre‐LCPB mid‐Ordovician sediments.

Seven species of graptoloid graptolites are described from Hirnantian and lower Rhuddanian formations of the Austrian part of the Carnic and western Karavanke Alps. The Plöcken Formation, of latest Ordovician (Hirnantian) age, yields the biozonal index graptolite <i>Metabolograptus persculptus </i>in the Cellon Reference Section and, tentatively, the Feistritzgraben Section. A distinctive graptolite assemblage indicating an earliest Silurian (early Rhuddanian) age comes from the Waterfall Section near Zollnersee Hütte. Along with the presence of the biozonal index <i>Parakidograptus acuminatus </i>and accompanying taxa, common <i>Rickardsograptus</i>? <i>bifurcus </i>(Ye) has been recorded - for the first time outside China. The absence of <i>Neodiplograptus lanceolatus </i>Štorch & Serpagli, <i>Normalograptus trifilis </i>(Manck) and other easily recognizable lowermost Rhuddanian species which are dominant in this level throughout peri-Gondwanan Europe indicates the peculiar character of the <i>acuminatus </i>Biozone assemblage encountered in the Carnic Alps