The Mirdita Ophiolite Zone in Albania is associated with widespread mélanges containing components of up to nappe-size. We dated matrix and components of the mélange by radiolarians, conodonts, and other taxa. The components consist of radiolarites, pelagic limestones and shallow-water limestones, all of Triassic age, as well as ophiolites. Triassic radiolarite as a primary cover of ophiolite material proves Middle Triassic onset of Mirdita ocean-floor formation. The mélange contains a turbiditic radiolarite-rich matrix (''radiolaritic flysch''), dated as Late Bajocian to Early Oxfordian. It formed as a synorogenic sediment during west-directed thrusting of ophiolite and sediment-cover nappes representing ocean floor and underplated fragments of the western continental margin. The tectonic structures formed during these orogenic events (''Younger Kimmeridian or Eohellenic Orogeny'') are sealed by Late Jurassic platform carbonates. The geological history conforms with that of the Inner Dinarides and adjoining areas; we therefore correlate the Mirdita-Pindos Ophiolite Zone with the Vardar Zone and explain its present position by far-distance west-directed thrusting.

Although many case studies describe stromatoporoid-rich Jurassic reefs, there are only few reliable data as to their distribution pattern. This is in part due to a largely taxonomic and systematic focus on the enigmatic stromatoporoids which now are interpreted as a polyphyletic informal group of demosponges by most specialists. The common co-occurrence of Jurassic scleractinian corals and stromatoporoids might, at first hand, point to very similar environmental demands of both organismic groups, but autecological considerations as well as evaluation of stromatoporoid distribution patterns should allow for a much more refined interpretation. This study concludes that Jurassic corals and stromatoporoids show a relatively broad overlap of environmental demands but their maximum ecological tolerances appear to differ considerably. Jurassic corals were dominating in mesotrophic to mildly oligotrophic, slightly deeper settings, where they largely outcompeted stromatoporoids. On the other hand, stromatoporoid growth was particularly favoured in very shallow water, strongly abrasive, high-energy settings as well as in possibly overheated waters. Many taxa and growth forms were very tolerant towards frequent reworking and redistribution, a feature which is compatible with the sponge nature of the stromatoporoids. As such, stromatoporoid facies may be common in low-accommodation regimes, giving rise to frequent "shelf shaving" and redistribution across wide shelf areas. The mixed coralstromatoporoid reefs from the margins of isolated IntraTethys platforms are interpreted to be indicative of oligotrophic normal marine waters. This is corroborated by statistical cluster analysis of stromatoporoid taxa from representative areas. In addition, Arabian stromatoporoid occurrences might have been adapted to overheated and slightly hypersaline waters. There also are a few exceptional stromatoporoid taxa which might have had environmental tolerances different from the bulk tolerances of other Jurassic stromatoporoids. Part of our interpretations are preliminary and should stimulate further research. However, the present results already help explain the observed compositional differences between Jurassic North Tethys/North Atlantic, Intra-Tethys, and South Tethys shallow-water reefs and platforms.

The Late Jurassic-Lower Cretaceous microorganisms incertae sedis Lithocodium aggregatum Elliott and

No abstract

Several Late Jurassic (Kimmeridgian?-Tithonian) to Early Cretaceous (Late Berriasian-Valanginian) shallow-water carbonate clasts of different facies are contained in mass-flow deposits in a pelagic sequence in the Kurbnesh area of central Albania. These clasts are used to reconstruct shallow-water carbonate platforms, which formed on top of the radiolaritic-ophiolitic wildflysch (ophiolitic mélange) of the Mirdita Zone. Stratigraphic interpretation of the platform carbonates was compiled on basis of calcareous algae, benthic foraminifera, and calpionellids. From biostratigraphic data and microfacies analysis, the Neocomian clasts can be directly correlated with autochthonous platform carbonates of the western part of the Munella carbonate platform, which at least reaches up to the Late Aptian. A Late Jurassic precursor platform (Kurbnesh carbonate platform; nomen novum) was completely eroded until the Valanginian and is only documented by the clasts described here. It was deposited on top of the Mirdita Ophiolite Zone nappe stack, which formed during the Middle to Late Jurassic Kimmeridian orogeny. Thrusting and imbrications as well as the formation of the syntectonic wildflysch (mé-lange) therefore occurred much earlier than previously assumed. Our results constrain the Kimmeridian orogeny, which was controlled by the closure of the Neotethys Ocean, and show excellent correlation with the Eastalpine-Dinaric-Hellenic orogenic system. ZUSAMMENFASSUNGAus mikrofaziell unterschiedlichen Ober-Jura-(Kimmeridgium?/Tithonium) und Unter-Kreide-Flachwasserkalk-Klasten (Ober-Berriasium bis Valanginium), die in Form von Brekzienkörpern in pelagischen Sedimenten in der Gegend von Kurbnesh in Zentral-Albanien auftreten, werden jene Karbonatplattformen rekonstruiert, welche ursprünglich die Serie des radiolaritischenophiolithischen Wildflysches (Ophiolith-Mélange) in der Mirdita-Zone bedeckten. Die Stratigraphie basiert auf Kalkalgen, Benthosforaminiferen und Calpionellen. Stratigraphische und mikrofazielle Kriterien erlauben, die Neokom-Karbonatklasten mit den autochthonen Seichtwasser-Karbonaten des westlichen Abschnittes der Munella-Plattform, die mindestens bis in das obere Aptium reicht, in direkten Zusammenhang zu bringen. Eine heute vollständig erodierte Ober-Jura Karbonatplattform im Hangenden der Ophiolithdecken wird durch Komponentenanalyse rekonstruiert. Diese Ober-Jura-Karbonatplattform (Kurbnesh Karbonatplattform; nomen novum) war bis zum Valanginium vollständig erodiert und lässt sich nur durch die beschriebenen Klasten rekonstruieren. Sie wurde auf der Mirdita-Ophiolithzone abgelagert und versiegelte den Deckenstapel, der sich während der mittel-bis oberjurassischen Kimmeridischen Orogenese bildete. Deckenbau und Imbrikation sowie die Bildung des syntektonischen Wildflysches (der Mélange) fanden daher viel früher statt als bisher angenommen. Unsere Ergebnisse grenzen die Kimmeridische Orogenese, die von der Schließung des Neotethys-Ozeans gesteuert wurde, zeitlich ein, und zeigen sehr gute Korrelation mit dem Ost...