Carnic Alps Research Articles

Middle–late Asselian (Early Permian) fusulinid fauna from the post-Variscan cover in NW Anatolia (Turkey): Biostratigraphy and geological implications

The earliest autochthonous cover of the Variscan basement of the Sakarya Composite Terrane (SCT) in NW Anatolia is represented by basal conglomerates and limestones. The microfacies types of the limestones in ascending order are: (1) bioclastic grainstone/packstone, (2) fusulinid grainstone/packstone, (3) smaller foraminiferal grainstone/packstone, (4) Anthracoporella (dasycladale) grainstone/packstone, and (5) wackestones. Twenty-three species assignable to 15 genera of fusulinids were recovered from the studied materials of the Kadirler section; Quasifusulina guvenci nov. sp. and Pseudoschwagerina beedei magna nov. subsp. are created. Rugosofusulinids, sphaeroschwagerinids, pseudoschwagerinids, occidentoschwagerinids, pseudochusenellids, quasifusulinids, rugosochusenellids and paraschwagerinids are the main faunal elements of the succession, which shows two distinct faunal intervals. Eoschubertella, Schubertella, Biwaella?, Rugosofusulina stabilis group, and Pseudochusenella correspond to the first interval at the base; the second interval is characterized by the species of Sphaeroschwagerina, Pseudoschwagerina, Occidentoschwagerina, the Rugosofusulina latispiralis group, and diverse quasifusulinids. A biostratigraphic correlation shows that the Kadirler section in the SCT in NW Anatolia shares many common species with Central Asia in the East but especially with the Carnic Alps and Karavanke Mountains in the West. The new data suggest that the close faunal relationship in the Late Carboniferous between eastern Alps, Ural Mountains, NW Turkey and Central Asia also continued during the Asselian.

Environmental control on the end of the Dolomia Principale/Hauptdolomit depositional system in the central Alps: Coupling sea-level and climate changes

The Norian in the Western Tethys is characterised by the deposition of early-dolomitised inner platform facies (Dolomia Principale/Hauptdolomit, DP/HD), bordered on the landward side by terrigenous coastal deposits (Keuper) and on the seaward side by calcareous backreef and reefal facies (Dachstein Limestone) passing basinward to open-sea sediments (Hallstatt facies). The inner carbonate platform is locally (Lombardy Basin, Carnic Alps, Central Austroalpine) dissected by normal faults leading to the development of intraplatform troughs. Close to the Norian–Rhaetian boundary, sedimentation records an abrupt environmental change both on platform top and basins all over the Western Tethys (e.g. Western Carpathians, Transdanubian Range, Alps, Central Apennine). The top of the Dolomia Principale locally emerged, reflecting a major eustatic sea-level fall. Emersion is recorded in favourable settings by the development of polycyclic paleosols up to 30 m thick. In the Norian intraplatform basins, the succession is capped by 4 to 8 m of thin-bedded, fine-grained limestones yielding abundant remnants of fishes and terrestrial reptiles. Fossil concentration as well as sedimentological features is indicative of reduced sedimentation rates due to decreased carbonate production, induced by the emersion of the platform top. The sea-level fall was followed by deposition of mixed fine-grained siliciclastic–carbonate successions (e.g. Riva di Solto Shale, Kössen beds, “ Rhaetavicula contorta beds”, Fatra Formation). Stratigraphic evidence indicates a dry climate in the Western Tethys during the Norian, as indicated by the presence of evaporites (Burano, Apennine) and arid to semi-arid coastal to playa settings (Upper Keuper, Germany). In contrast, the basal layers of the basinal shales show evidence of wet climate. The end of the Norian depositional system records two different phenomena: (1) an important sea-level fall was responsible for the emersion of the platform top and deposition of a condensed horizon in the basins; and (2) transition from dry to humid climate. The observed evolution is explained with a global cooling which caused the rapid sea-level fall responsible for the abrupt end of the DP/HD depositional system and the shift of the boundary between arid and temperate climate belts, which modified the distribution and amount of rainfall, triggering the deposition of shales along the Western Tethys margin.

Basic stratigraphy and tectonics of the Southern Alpsaround the Giudicarie Lineament (Southern Alps, Italy)

One of the most fascinating problems of the Southern Alps is the meaning of the strong structural indentation between the Sothern Alps and the Austroalpine units along N-Giudicarie fault, where the Europe-verging nappe stack of the Alps (Austroalpine and Penninic nappes) and the Africa-verging thrust belt of the Southern Alps face each other and appear sinistrally displaced more than 50 km. Starting from the beginning of ‘900 century, several generations of geologists considered the sinistral slip on the fault responsible of the indentation of the Alps along the Giudicarie lineament, occurred during N-S Neogene compressions. Old and new data, on the contrary, indicate that most of the extensive sinistral displacement affecting the N Giudicarie Lineament originated during late Cretaceous-early Eocene times. The Pre-Adamello structural belt is present only in the internal Lombardy zone, located W of the Adamello massif. This belt is unknown in the Dolomites and surrounding areas located to the E of the Giudicarie lineament. Upper Cretaceous-early Eocene thick Flysch deposits of Lombardy and Giudicarie are well preserved along the Southern and Eastern border of the Pre-Adamello belt (S-verging Alpine orogen). Towards the E, in the Dolomites and in the Carnic Alps and external Dinarides, only incomplete remnants of Flysch deposits, Aptian-Albian and Turonian-Maastrichtian in age, are present. They can be considered as equivalent to those of Lombardy and Giudicarie formerly in connection along the N-Giudicarie corridor. All these deposits may correspond to the foredeep syntectonic sedimentary records of the S border of the new Cretaceous-Eocene orogenic belt of the Alps. Differences between the eastern and western blocks (the Dolomites versus the pre-Adamello belt) can be related to the Cretaceous-Eocene N Giudicarie transfer zone, which produced the basic structural setting discussed here. Due to these data and interpretations the Giudicarie bending of the Alps appears to be a late Mesozoic-early Tertiary tectonic inheritance rather than the result of the Neogene compressional evolution. During the late Eocene to early Oligocene the transfer zone was utilized for the ascent and emplacement of the Paleogene Adamello batholith. Oligocene to Neogene compressional evolution inverted the N-Giudicarie fault into a back-thrust of the Austroalpine units over the South-Alpine chain rearranging most of the former structural setting.

The influence of terrestrial run off on marine biotic communities: An example from a thrust-top carbonate ramp (Upper Pennsylvanian foreland basin, Picos de Europa, NW Spain)

High-diversity marine biotic communities characterize the lower Kasimovian (Upper Pennsylvanian) carbonates of the Las Llacerias Formation in the Ándara Massif (Picos de Europa Province, Cantabrian Mountains, Spain). The carbonates accumulated on a small thrust-top ramp system. Within the shallow, low-energy and euphotic realms, biotic communities were characterized by abundant photozoans (calcareous algae and cyanobacteria) and heterozoans including filter and suspension feeders (calcareous and siliceous sponges, bryozoans, brachiopods, crinoids), diverse other metazoans (rugose solitary and colonial corals, tabulate corals, bivalves, gastropods and echinoids), benthic foraminifers including very abundant small incrusting “tubiforms” and conspicuous swarms of cement-filled spheres (calcispheres or Penella). Small-sized buildups of chaetetid sponges, syringoporids, branching rugose corals, Anthracoporella and phylloid algae commonly developed in these shallow-water environments. Meanwhile, mud mounds formed at greater water depths, mostly below the lower limit of the phothic zone. The occurrence of such diverse biotic communities and the grain composition of the shallow-water deposits, not recorded in the platform-top successions of the antecedent Bashkirian–Moscovian carbonate shelf (Valdeteja and Picos de Europa formations) are interpreted as linked to increased nutrient levels (mesotrophic to mildly eutrophic conditions) in the actual sea-surface water. The nutrients are inferred to have resulted from land-derived fluxes from the rivers draining the adjacent growing Variscan Orogenic chain. Nutrients were subsequently transported into the narrowed marine shallowing foreland basin located in the eastern side of Pangea, within the palaeoequatorial humid belt. Comparison to the Pennsylvanian Auernig Group in the Carnic Alps allows the discrimination between the influence of land-derived versus upwelling-derived nutrients, providing a useful tool in the interpretation of biotic assemblages in the fossil rock record.

Silurian sequence stratigraphy of the Carnic Alps, Austria

Sequence stratigraphy provides an alternative approach to correlation that may also serve as a predictive framework for the interpretation of sea-level and sedimentological change. The main aim of this study is to apply sequence stratigraphic concepts to the biostratigraphically well constrained shallow to moderately deep shelf carbonates and basinal graptolitic shale facies of the Silurian successions in the Carnic Alps of Austria in order to correlate the sequence packages and sea-level changes established there with those identified in other areas of North America and Europe. Documenting local sea-level curves is essential for determining global eustasy. The sea-level curve for the Silurian of the Carnic Alps has been elaborated within a refined stratigraphic framework for the Silurian based on conodont and graptolite biozonation [Melchin, M.J., Cooper, R.A., Sadler, P.M., 2004. The Silurian Period. In: Gradstein, F.M., Ogg, J.G., Smith, A.G. (Eds), A Geologic Time Scale. Cambridge University Press, Cambridge, pp. 188–201.]. In particular, the minor and frequent sea-level changes within the Silurian of the Carnic Alps are of special interest as these stratigraphic intervals are poorly preserved and not well studied in other Silurian localities. The interpretation of the field and microfacies analysis indicates major sequence boundaries in the Llandovery (3), Wenlock (3), Ludlow (3) and Přídolí–Lochkovian (2) which may be correlated with coeval disconformities in the Appalachian Foreland Basin of eastern North America and/or in the Welsh Basin of the British Isles. The following times appear to represent relative sea-level highstand maxima in the Silurian of the Carnic Alps, as indicated by dark, graptolitic shales in deep shelf to basinal carbonate-dominated sections: a) early Aeronian, approximately the Coronograptus cyphus graptolite Zone/ Demirastrites triangulatus graptolite Zone), b) the early Telychian ( Oktavites spiralis graptolite Zone; Pterospathodus celloni conodont Superzone), c) late Telychian (lower Pterospathodus a. amorphognathoides conodont Zone); d) early to middle Sheinwoodian ( Kockelella ranuliformis to Ozarkodina sagitta rhenana conodont Zones; Monograptus riccartonensis graptolite Zones); e) mid-Wenlock ((?upper Kockelella walliseri conodont Zone; Cyrtograptus rigidus graptolite Zone); f) mid Homerian ( Ozarkodina bohemica conodont Zone; Gothograptus nassa graptolite Zone); g) near the Wenlock–Ludlow boundary ( Neodiversograptus nilssoni graptolite Zone); h) Polygnathoides siluricus conodont Zone; i) near the Ludlow–Přídolí boundary (upper Ozarkodina snajdri Interval Zone); j) lower Přídolí ( Monograptus parultimus graptolite Zone) and k) at the Silurian–Devonian boundary (earliest Lochkovian: Icriodus woschmidti woschmidti conodont Zone. Of these, the earlier (at least b–e) are well represented in the Appalachian Basin, as in Avalonian sections in Great Britain and in Baltica. Johnson [Johnson, M.E., 2006. Relationship of Silurian sea-level fluctuations to oceanic episodes and events. GFF 128, 115–121.] documented eight major highstands in global sea-level during the Silurian. The temporal resolution obtained in the Carnic Alps for local sea-level changes allows for refinement of the Telychian to Přídolí sea-level curve, as the stratigraphic successions are chronologically well-defined using both conodont and graptolite biostratigraphy and K-bentonite levels. Nearly all inferred deepenings in the Carnic Alps section, with the exception of that in the Polygnathoides siluricus conodont Zone, approximately match highstands recorded on the Silurian sea-level curves of Johnson [Johnson, M.E., 1996. Stable cratonic sequences and a standard for Silurian eustasy. In: Witzke, B.J., Ludvigson, G.A., Day, J. (Eds.), Paleozoic sequence stratigraphy – Views from the North American Craton. Geol. Soc. Am. Spec. Pap. vol. 306, Boulder, pp. 203–212., Johnson, M.E., 2006. Relationship of Silurian sea-level fluctuations to oceanic episodes and events. GFF 128, 115–121.]; however, the two Telychian highstands are not distinguished but rather are combined as highstand 4 on the Johnson curve, although they are recognized by Loydell [Loydell, D.K., 1998. Early Silurian sea-level changes. Geol. Mag. 135 (4), 447–471.], and the upper Kockelella walliseri conodont Zone deepening is not explicitly numbered by Johnson. These similarities suggest pervasive and probably eustatic events that are manifested in the Apulia Terrane [Cocks, L.R.M., Torsvik, T.H., 2002. Earth geography from 500 to 400 million years ago: a faunal and palaeomagnetic review. J. Geol. Soc. Lond. 159 (6), 631–644.], Laurentia and Avalonia during these time intervals.

FACIES, MICROFOSSILS (SMALLER FORAMINIFERS, CALCAREOUS ALGAE) AND BIOSTRATIGRAPHY OF THE HUECO GROUP, DOÑA ANA MOUNTAINS, SOUTHERN NEW MEXICO, USA

The Lower Permian Hueco Group of the Dona Ana Mountains (south-central New Mexico, USA) is studied in three sections (A, B, C) located east of Leasburg, Dona Ana County. Regionally, the Hueco Group has been subdivided into four formations termed Shalem Colony, Community Pit, Robledo Mountains and Apache Dam formations; the lower three are exposed in the Dona Ana Mountains. The succession shows a shallowing upward trend from dominantly shallow, open marine conditions (Shalem Colony Fm) to increasingly restricted marine environments (Community Pit Fm) and siliciclastic influx (Robledo Mountains Formation). Sedimentation, particularly siliciclastic influx, was mainly controlled by reactivation of basement uplifts during the last pulses of the Ancestral Rocky Mountains deformation. The microfossils and microfacies of the two first formations are studied in detail here. The Shalem Colony Formation can be divided into a lower biozone with Triticites pinguis , which is Newwellian (latest Pennsylvanian, early Wolfcampian) in age, and an upper division characterized by the first occurrence of Geinitzina , and lower-middle Asselian (late early Wolfcampian) in age. By comparison with the subdivisions of the Carnic Alps (Austria), the Community Pit Formation is characterized as Sakmarian (middle Wolfcampian) in age due to the first occurrence of the genus Pseudovermiporella , and its probable complete phylogeny from Hedraites . The late Asselian is restricted to the uppermost part of the Shalem Colony and lowermost part of the Community Pit Formation. Due to the occurrence of Pseudoreichelina the Robledo Mountains Formation is dated as Artinskian (late Wolfcampian). Some bioconstructions of Archaeolithophyllum are emphasized, as well as some species of foraminifers-globivalvulinids, Miliolata and Nodosariata.

Upper Silurian and Lower Devonian conodonts from the Monte Cocco II Section (Carnic Alps, Italy)

Upper Silurian and Lower Devonian conodonts from the Monte Cocco II Section (Carnic Alps, Italy)

Graptolite faunas of the Llandovery “phtanites” at Les Fresnaies (Chalonnes-sur-Loire, southeastern Armorican Massif): Palaeontology and biostratigraphy

In the SE of the Armorican Massif (France), the Ordovician-Silurian transition and the lower part of the Silurian are exposed at the locality Les Fresnaies at Chalonnes-sur-Loire. The Silurian graptolitic phtanites (black cherts) are richly fossiliferous. Detailed sampling allows a description of the graptolite faunas and a precise stratigraphical analysis of the succession that comprises the whole of the Rhuddanian and Aeronian stages. Both the Llandovery graptolite assemblages and the lithologies of Les Fresnaies are similar to those of other lower Silurian successions throughout peri-Gondwanan Europe, like Portugal, Spain, Sardinia, Bohemia, Germany and Carnic Alps, and in the Middle East (Jordan and Saudi Arabia).

Latest Permian foraminifers from the Vlasic mountain area, northwestern Serbia

Foraminifers from the Permian-Triassic boundary interval in the upper part of the "Bituminous Limestone" Formation of the Komiri section, northwestern Serbia are described and illustrated here for the first time. Four new species of foraminifers are described: Hemigordius komiricensis n. sp., H. smiljkae n. sp., Multidiscus vlasicensis n. sp., and Eomarginulinella serbica n. sp. The genus Eomarginulinella Sosnina 1969 is considered to be a valid genus and reinstated herein. The youngest Late Permian foraminifers are found together with conodonts of the Lower Hindeodus praeparvus Zone, the next to the last of the youngest conodont zones of the Upper Permian. The assemblage of the foraminifers from the upper part of the "Bituminous Limestone" in northwestern Serbia is most similar to coeval foraminiferal assemblages from the upper Changhsingian Belolabinskaya Group of the northwestern Caucasus and from the Nagyvisnyo Limestone Formation of the Bukk Mountains in northeastern Hungary. It is less similar to coeval foraminiferal assemblages of the Carnic Alps, Central Taurides of Turkey, Transcaucasia and China.

Environmental change during the Late Famennian and Early Tournaisian (Late Devonian–Early Carboniferous): implications from stable isotopes and conodont biofacies in southern Europe

AbstractA biostratigraphic correlation of the Devonian/Carboniferous (D/C) boundary sections from the Carnic Alps, the Graz Palaeozoic, the Montagne Noire and the Pyrenees resulted in a high‐resolution record of the carbon isotopic composition of micrites (δ13Ccarb), of sedimentary organic matter (δ13Corg) and of oxygen isotope ratios of conodont apatite (δ18Ophosph). The studies focused on the interval between the Upper postera Zone (Late Famennian) and the sandbergi Zone (Lower Tournaisian). For the first time, weak but significant positive carbon isotope excursions in micrites and in the sedimentary organic matter is reported from the Middle and Upper expansa zones of the Carnic Alps. They coincide with a decrease in the oxygen isotope values of conodont apatite. The excursions indicate changes in the global carbon cycle during an episode of high seawater temperatures, and correlate with sedimentary change and a stepwise eustatic rise in the Rhenish Massif. High carbon isotope values were also measured in limestones from the Graz Palaeozoic in the Upper praesulcata Zone, which were previously reported from the Rhenish Massif, Carnic Alps, Montagne Noire and the North America continent. The change from a palmatolepid–polygnathid conodont biofacies to a palmatolepid–bispathodid–branmehlid biofacies in the expansa Zone in the Carnic Alps is obviously influenced by anoxic conditions and repeated transgressive phases. The protognathodids and the polygnathids start to radiate in the Upper praesulcata Zone, after the main end‐Famennian extinction episode. This is connected with the disappearance of the palmatolepids, and environmental stress created by worldwide anoxic conditions, climate change and sea‐level changes, stimulated the radiation of both protognathodids and the polygnathids. The regional correlation of the geochemical records as well as interpretations of these records on a global scale indicate that changes in conodont biofacies of Late Famennian–Early Tournaisian limestones were caused by a complex pattern of environmental changes. Copyright © 2008 John Wiley & Sons, Ltd.

LATE CARBONIFEROUS AND EARLY PERMIAN FUSULINOIDEANS IN THE CENTRAL TAURIDES, TURKEY: BIOSTRATIGRAPHY, FAUNAL COMPOSITION AND COMPARISON

The Upper Carboniferous and Lower Permian rock units in the Hadim area, central Taurides, Turkey, are biostratigraphically divided into eleven fusulinoidean zones in ascending order: the Protriticites variabilis , Montiparus umbonoplicatus and Schwageriniformis schwageriniformis Zones in the Kasimovian; the Jigulites aff. formosus , Daixina asiatica and Rugosofusulina sp. A Zones in the Gzhelian; the Paraschwagerina sp. and Dutkevichia complicata Zones in the Asselian; the Paraschwagerina pseudomira and Robustoschwagerina nucleolata Zones in the Sakmarian; and the Dunbarula ? sp. Zone of possible Artinskian age, according to the geochronologic calibration by fusulinoideans. Basal Kasimovian strata, Kasimovian-Gzhelian boundary strata and lower Asselian strata are missing, due to erosion and/or nondeposition, based on faunal analysis of 61 species in 31 genera. Lithologies and fossils suggest that deposition of the studied rock units occurred under shallow, high energy, tropical coastal conditions, influenced by glacioeustatic sea level fluctuations. Early groups of schwagerinids dispersed rapidly, so that the Kasimovian faunas of the Taurides have both European and Central Asian affinities. Faunal similarity between the Hadim area and stratotype regions of the Moscow Basin and the Southern Urals declined gradually in Gzhelian time, declined more rapidly in the Asselian, and reached its low point in the Sakmarian. Many common species occur in the Hadim area and Central Asia (southern Fergana and southwest Darvas), the eastern Mediterranean Sea regions (Slovenia, Croatia, Chios Island, and other localities of Turkey), and the Carnic Alps, especially in the Sakmarian fauna containing Robustoschwagerina , Pseudoschwagerina , Paraschwagerina , Quasifusulina , Eoparafusulina and Darvasites .

Depositional environment of Upper Carboniferous – Lower Permian beds in the Karavanke Mountains (Southern Alps, Slovenia)

Late Paleozoic rocks were studied in detail in the Dovžanova soteska section. The Upper Carboniferous sedimentary succession, correlated with upper part of Auernig and Schulterkofel Fm. in the Carnic Alps, indicates cyclic clastic-carbonate deposition in a coastal to shallow marine ramp setting with strong influence of coarse-grained fluvial-deltaic siliciclastics from the hinterland, storm dominated regime of nearshore sediments, and offshore algal buildups. The Lower Permian sequence is developed differently from its time equivalent Grenzland Fm. and is subdivided into Dovžanova soteska Fm., Born Fm., and Rigelj beds. It is marked by the formation of a reef mound on the platform margin. Open-marine inner platform close to the marginal shoals represented the depositional environment of the mixed carbonate-siliciclastic sediments. Thus, a platform evolution from a ramp into a rimmed shelf is suggested.

Early Ordovician ostracods from Argentina: their bearing on the origin of binodicope and palaeocope clades

New species of ostracods are described from the Tremadoc of the Cordillera Oriental (Argentina). These are among the earliest well-documented records of Ostracoda sensu stricto. The ostracod assemblages are sourced from shallow marine clastics and are dominated by palaeocopes (Eopilla waisfeldaen. sp.,Nanopsis coquenan. sp.), and the binodicopeKimsella luciaen. gen. and sp.EopillaandKimsellashow affinities with species from paleocontinental Gondwana (e.g., Ibero-Armorica, Turkey, Australia, Carnic Alps), butNanopsisis previously known only from paleocontinental Baltica. This study confirms that two of the major clades of Ordovician ostracods, namely the Binodicopa and the Palaeocopa, were already geographically widespread during the late Tremadoc, suggesting a still earlier origin for these groups, possibly from within the Cambrian to Early Ordovician Bradoriida. Evidence from soft-part anatomy indicates that phosphatocopids, the other group hypothesized to be ancestral ostracods, have apomorphies that preclude them as direct ancestors. The origin of ostracods is more likely to be found within the Bradoriida, a probable polyphyletic group that resembles Early Ordovician ostracods in the external sculpture of their bivalved carapace. Evidence from carapace morphology suggests that the ancestors of true ostracods might lie within the bradoriid groups Beyrichonidae and Hipponicharionidae, a hypothesis that can only truly be tested when more evidence from fossilized soft tissues becomes available.

Dichotrachelus kahleni sp. n., a new weevil species from the Carnian Alps, north-eastern Italy (Coleoptera, Curculionidae, Entiminae)

A new species of Dichotrachelus is described from the Carnian Alps, Friuli-Venezia Giulia, north-eastern Italy (type locality: Moggio Udinese, Mount Sernio). The new species belongs to the D. luzei species group, previously known from Mt. Pasubio, Veneto, and Mt. Grintavec, Slovenia; its discovery in the Carnian Alps fills thus a broad gap in the distribution of this group. It is associated with Saxifraga caesia in limestone habitats; imagoes, apparently hatching in late summer, live in the small clumps of the host plants; some larvae were found among the roots. Additional specimens moderately distinct were found in the Julian Alps: taxonomic relationships between these and the type specimens of D. kahleni are discussed.

Late Devonian – Early Carboniferous vertebrate microremains from the Carnic Alps, northern Italy

Vertebrate microremains from the Late Devonian–Early Carboniferous of the Carnic Alps are predominantly chondrichthyan, with minor placoderm and actinopterygian remains. The faunas are sparse and, with very few exceptions, occur only in conodont-rich pelagic limestones (Pramosio Limestone) representative of the palmatolepid-bispathodid conodont biofacies. Phoebodont and jalodont chondrichthyans, also reflecting open-ocean environments, predominated during the Famennian, and eventually symmoriids seem to predominate during the Early Carboniferous. The presence of Siamodus in this assemblage gives a new locality for this genus known from few regions in the world and allows confirming its stratigraphical range ( limpidus Zone) and its relation to deep-water environments. The Late Devonian vertebrate faunas are tropical and cosmopolitan, having much in common with coeval taxa from the North-Gondwanan margins and Asian terranes. Composition of the vertebrate faunas is consistent with the Carnic Alps terrane having occupied a position intermediate between Gondwana and Laurussia, as hypothesized by various authors, but because of sparsity of the taxa represented and the pronounced cosmopolitan nature of both the conodont and vertebrate faunas, the data are not compelling.

Using GB-SAR technique to monitor slow moving landslide

A Ground-Based SAR (GB-SAR) interferometer was employed to measure the surface displacements of a landslide occurring in the Carnian Alps, north-eastern Italy, which has affected a national road and seriously damaged a road tunnel still under construction. Moreover, since the landslide is located on the left bank of the Tagliamento River Valley, it is feared that this mass movement might dam the river, creating a basin that would increase natural hazard for the valley inhabitants. The data collected from December 2002 to July 2005 by a conventional monitoring system, consisting of a GPS network and boreholes equipped with inclinometric tubes, showed that the landslide was moving at a quasi-constant rate of about 3 cm per year. Due to the slow deformation rate of the landslide, a recently developed GB-SAR technique based on the analysis of a restricted ensemble of coherent points was used. Two surveys, each lasting two days, were planned in December 2004 and July 2005, in order to map and measure the surface displacements that occurred over time. The results from the radar were compared with the ones derived from the GPS monitoring network. An agreement was achieved among the data collected, showing the capability of the GB-SAR technique to measure displacements even within a time span of several months between the surveys.

Late Paleozoic reef mounds of the Carnic Alps (Austria/Italy)

The Late Paleozoic (early Kasimovian–late Artinskian) sedimentary sequence of the Carnic Alps (Austria/Italy) is composed of cyclic, shallow-marine, mixed siliciclastic–carbonate sedimentary rocks. It contains different types of skeletal mounds in different stratigraphic levels. The oldest mounds occur at the base of the Auernig Group, within a transgressive sequence of the basal Meledis Formation. These mounds are small and built by auloporid corals. Algal mounds are developed in the Auernig Formation of the Auernig Group, forming biostromes, and Lower Pseudoschwagerina Limestone of the Rattendorf Group forming biostromes and bioherms. The dominant mound-forming organism of these mounds is the dasycladacean alga Anthracoporella spectabilis. In mounds of the Auernig Formation subordinately the ancestral corallinacean alga Archaeolithophyllum missouriense is present, whereas in mounds of the Lower Pseudoschwagerina Limestone a few calcisponges and phylloid algae occur locally at the base and on top of some Anthracoporella mounds. Mounds of the Auernig Formation formed during relative sea level highstands whereas mounds of the Lower Pseudoschwagerina Limestone formed during transgression. The depositional environment was in the shallow marine, low-turbulence photic zone, just below the active wave base and lacking siliciclastic influx. The algal mounds of the Carnic Alps differ significantly from all other algal mounds in composition, structure, zonation and diagenesis; the formation of the mounds cannot be explained by the model proposed by Wilson (1975). The largest mounds occur in the Trogkofel Limestone, they are composed of Tubiphytes/Archaeolithoporella boundstone, which shows some similarities to the “ Tubiphytes thickets” of stage 2 of the massive Capitan reef complex of the Guadalupe Mountains of New Mexico/West Texas.

Polyphase metamorphism in the eastern Carnic Alps (N Italy–S Austria): clay minerals and conodont Colour Alteration Index evidence

Thermal evolution of the Palaeozoic–Triassic sequences of the Carnic Alps has been characterized by b cell dimension and Kubler Index (illite “crystallinity”) of K-white micas (KI), Arkai Index (AI) of chlorites, clay mineral assemblages and conodont Colour Alteration Index (CAI). Data indicate at least two metamorphic events, Variscan and Alpine. In the older event high anchizonal conditions predominated although epizonal conditions were reached over wide areas. It was characterized by low-intermediate pressure facies. The thermal peak was mainly due to an extensional regime during the Bashkirian. A younger thermal overprint generated by Alpine orogeny was of lower grade, reaching high diagenetic–anchizonal conditions characterized by high-pressure facies. Inverted metamorphic patterns are associated with middle to late Miocene thrusting. Hydrothermal alteration in the northern part of the region can be linked with emplacement of Oligocene plutons and high heat flow along the Periadratic lineament.

Ostracods from the Upper Ordovician Borenshult fauna, Sweden

The Borenshult locality was a temporarily exposed, richly fossiliferous locality with the Hirnantia fauna. It yielded a rich and diverse ostracod assemblage, the Harpabollia harparum association. This association differs from other Upper Ordovician and Llandoverian ostracod faunas of Baltoscandia. In terms of graptolite zonation, the age of the H. harparum association may be characterised as extraordinarius-persculptus. The age and the fact that the H. harparum association occurs together with macrofossils typical of the Hirnantia-Dalmanitina fauna suggest that it may be regarded as part of the Hirnantia fauna in a wider sense. The record of the characteristic taxa of this particular association from the Carnic Alps and Bohemia suggests an immigration of the most characteristic members of the H. harparum association into the Baltoscandian Palaeobasin from higher palaeolatitudes. The data suggest that collection from the debris at Borenshult provided not only Hirnantian material, but also material from the pre and post-Hirnantian.

Eurytholia plates (Problematica) from the late Silurian of the Austrian Carnic Alps

A small fauna of phosphatic plates of the enigmatic organism Eurytholia bohemica [Ferretti A., Serpagli E., Štorch P., 2006. Problematic phosphatic plates from the Silurian-Early Devonian of Bohemia, Czech Republic. Journal of Paleontology 80 1026–1031.], is described for the first time from upper Silurian beds of Austria. Other known Silurian occurrences of this taxon were restricted to Bohemian localities even if the genus had been previously reported from several Ordovician outcrops. The extension of E. bohemica from the microcontinent of Perunica to that of Carnica suggests that Eurytholia was not an uncommon constituent of Silurian fauna, at least at intermediate latitudes in the southern hemisphere.