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The distal part of a mass flow deposit has been excavated across an area of 400 m2 in the basinal facies of the Eckfeld Maar. The high concentration and diversity of fossils in mainly excellent preservation (i.e. leaves, fruits/seeds, wood, molluscs, vertebrate teeth, and bones such as undeformed sculls) is unique and underline its outstanding importance concerning sedimentological, taxonomical, and...
The siliciclastic, up to 4,000 m thick Upper Triassic–Bajocian Shemshak Formation is widespread across the Iran Plate, especially in the Alborz Mountains of northern Iran. In contrast to its lower, generally non-marine part, the upper part is marine. Based on the Tazareh section of the eastern Alborz, an integrated analysis of this marine interval is presented. The 1,700 m thick marine sedimentary...
Despite prejudices that comparisons of paleoecological patterns in modern and fossil reef communities are of doubtful validity, we compare the biologic response of living coralgal reefs in French Polynesia to environmental stress with an exceptionally well exposed Middle Permian sponge reef and Shamovella-microbial reef of the Capitan Limestone in New Mexico. In the western Tuamotu Archipelago, reef...
Work on secular oscillations of the ocean-atmosphere system has reached a particularly interesting stage, characterized by competing models that alternately invoke endogenic and celestial drivers. The most widely accepted concept is the icehouse-greenhouse cycle with an approximate length of 300 Ma. The concept holds that in the past 600 Ma the Earth has oscillated between a glacial mode and one of...
In the cold-temperate setting of the Swedish Kosterfjord, a 2-year experiment was launched in order to assess bioerosion rates and to investigate the endolithic borer communities in relation to light availability (relative bathymetry), hydrography and exposure time. The inventory of microendolithic traces, studied by SEM analysis of epoxy resin casts of planted bivalve shells, yields diverse ichnocoenoses...
The relationship between algae and depositional environment was studied in a limestone succession of Berriasian–Valanginian age. Several depositional environments were recorded from shallow subtidal to intertidal and supratidal, with salinity ranging from normal marine to fresh and/or supersaline water. The algal assemblages consist mainly of dasycladaleans, rivulariacean-type cyanobacteria and charophytes...
Light and dark bands in fully recrystallized fossil hermatypic corals are generally interpreted to represent annual growth increments reflecting a photosymbiotic life style—an interpretation of far reaching significance in palaeoecology. In this paper we describe annual growth bands in the colonial coral Porites in a perfect (aragonite and microstructures retained) and fully recrystallized (sparry...
Lacustrine stromatolites of the Norian Arnstadt Formation (“Steinmergelkeuper”) occur on top of asymmetric flooding–evaporation cycles of a closed lake basin. They have been investigated with regard to associated lithofacies and biota, microfabric and stable carbon and oxygen isotopes. The stromatolites of the “Middle Grey Series” are brecciated and reworked by a flooding event of a subsequent lake...
During the Early Permian, in the area of the Carnic Alps, a quartz-gravelly beach fringed a mixed siliciclastic-carbonate lagoon with fleshy algal meadows and oncoids; seaward, an ooid shoal belt graded down dip to a low-energy carbonate inner shelf with phylloid algal meadows. In limestones, foraminiferal biomurae and bioclast preservation record tapholoss by rotting of non-calcified organisms (interpreted...
Uniquely preserved Late Devonian calcispheres were found in a core of the deep borehole Sosnowiec IG-1 (Upper Silesia, southern Poland). These enigmatic calcareous microfossils are interpreted here as acritarchs that underwent an early post-mortem calcification. Remnants of organic walls preserved in the calcispheres suggest that they represent various acanthomorphic acritarchs, characteristic members...
Peloids are ubiquitous components in modern and fossil carbonates. The term peloid is non-genetic because the origin of these grains and the pathways of their formation are not fully understood. Based on Berriasian material originating from Dorset, southern England, we report here on peloids that result from the more or less in-place breakdown of previously micritized bivalve shells. The continuum...
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...
Recent and ancient carbonate platforms are major marine ecosystems, built by various carbonate-secreting organisms with different sensitivity for environmental change. For this reason, carbonate platforms are excellent sensors for changes in contemporaneous marine environments. A variety of ecosystem changes in carbonate platforms have previously been recognised in the aftermath of mass extinction...
Nautilus is not suitable as a model organism to infer biological functions, embryonic development, or mode of life in ammonoids. A brief review of the available morphological data is given and molecular data are added to discuss the usefulness of Spirula as a biological proxy for ammonoids. Indeed, there are many morphological hints indicating that Spirula could be a useful model organism for approaching...
Two colonial serpulid worm tubes—Filograna taurica n. sp. and Filograna serialis n. sp.—from the Upper Triassic (Norian) reef boulders occurring in Taurus Mts. (south Turkey) are described. As bafflers, both species of Filograna build microbioherms reaching dimensions of up to 15 cm. Both species were not known either in Turkey or in any other Triassic localities of the Tethyan realm.
A facies analysis of the epicontinental marine Cenomanian sediments of northern Germany shows the presence of 17 facies types (FTs, including several subtypes) which can be assigned to three facies associations: 1) an inner shelf facies association (FT 1–8) with high amounts of terrigenous material and/or high-energy depositional features, 2) a middle shelf facies association (FT 9–15) of predominantly...
Deeper shelf carbonates are often composed of relatively monotonous successions with few diagnostic sedimentological characteristics. The Upper Jurassic of southern Germany provides a classical example for deeper ramp carbonate environments, dominated by limestone/marl sequences including conspicuous sponge/microbial bioherms. Sedimentological analysis was integrated with stable isotope (O, C) and...
Recent pharetronid sponges were regarded as relict species in tropical and subtropical waters, inhabiting cryptic habitats on coral reefs and in caves. More recent findings of a new species of the genus Plectroninia off northern Norway, with an inner fused skeleton have changed that view. Recent investigations on the sponge fauna of the “Propeller Mound”, northern Porcupine Seabight, focusing on sponges...
Limestone-marl alternations represent a common type of fine-grained calcareous rhythmites during the entire Phanerozoic. Their diagenetic overprint, however, obliterates their value for palaeoenvironmental interpretations. The original mineralogical composition of the carbonate fraction (aragonite, high-Mg calcite, low-Mg calcite) would potentially yield important information on palaeoenvironmental...
The carbonate-evaporitic sequence of the Cañadón Asfalto Formation that crops out in Cañadón Carrizal (Chubut province, Argentina) is characterized by a lacustrine facies association. This sequence includes an extensive biohermal belt, flood facies with high lake-level and low lake-level stages, and desiccation–evaporation facies. The biohermal belt shows three growth-stages of microbial communities...
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