Abstract Fossil chondrichthyan teeth played an important part in the establishment of a scientific understanding of ‘formed stones’. Following a slowly emerging taxonomy, Louis Agassiz presented the first comprehensive guide to Palaeozoic chondrichthyans in the 1830s. The next contribution of any substance was Arthur Smith Woodward’s Catalogue of Fossil Fishes in the British Museum (Natural History) with a historical, descriptive and systematic review of the chondrichthyans, a group on which he already had an impressively large publication record. Initially stimulated by his observations on an articulated petalodont dentition ( Climaxodus ), Smith Woodward erected the Bradyodonti in 1921. Defined on the possession of dentitions with very slow growth rates, only seven or eight successional teeth produced throughout the lifetime of the fish, and retention rather than shedding of earlier teeth, primarily by fusion to later ones, the bradyodonts embraced petalodonts, psammodonts, copodonts and cochliodonts. The establishment and subsequent demise of the bradyodonts is briefly reviewed here.

Abstract: Establishing a Permian brachiopod biochronological scheme for global correlation is difficult because of strong provincialism during the Permian. In this paper, a brief overview of brachiopod successions in five major palaeobiogeographical realms/zones is provided. For Gondwanaland and peri-Gondwanan regions including Cimmerian blocks, Bandoproductus and Punctocyrtella (or Cyrtella ) are characteristic of the lower Cisuralian, as is Cimmeriella for the middle Cisuralian. As the Cimmerian blocks continued drifting north during the late Kungurian, accompanied by climate amelioration, contemporaneous brachiopods inhabiting these blocks showed a distinct shift from cold-water to mixed or warm-water affinities. However, coeval brachiopods in the Northern Transitional Zone (NTZ) are characterized by warm-water faunas and are associated with fusulinids in the lower Cisuralian. The Guadalupian brachiopods of the NTZ were clearly mixed between the Boreal and palaeoequatorial affinities. The end-Guadalupian is marked by the disappearance of a few characteristic genera, such as Vediproductus , Neoplicatifera and Urushtenoidea , in the Palaeotethyan region. The onset of the end-Permian mass extinction in the latest Changhsingian is clearly exhibited by the occurrence of the dwarfed and thin-shelled brachiopods commonly containing Paracrurithyris .

Abstract Several brachiopods which belong to the same genus Horridonia of late Early and early Late Permian age in Spitsbergen and Poland, respectively, have been petrographically and geochemically analysed to verify seasonal variation in stable carbon and oxygen isotope values for palaeoclimatological implications. The specimens of Horridonia timanica from Spitsbergen show distinct cyclicity reflective of seasonal pattern, while those of Horridonia horrida from Poland do not. These differences are explained by the fact that the former lived at high palaeolatitudes at the northern margin of the supercontinent Pangaea where the seawater temperature differences between winter and summer seasons were greater, as expressed in the isotopic composition of the skeletal materials. In contrast, the shell growth of Horridonia horrida was subjected to strong evaporative influence by climatic variations in the eastern area of Pangaea.

Abstract: This study describes the distribution and stratigraphic range of the Upper Palaeozoic–Mesozoic succession in the NE Atlantic region, and is correlated between conjugate margins and along the axis of the NE Atlantic rift system. The stratigraphic framework has yielded important new constraints on the timing and nature of sedimentary basin development in the NE Atlantic, with implications for rifting and the break-up of the Pangaean supercontinent. From a regional perspective, the Permian–Triassic succession records a northwards transition from an arid interior to a passively subsiding, mixed carbonate–siliciclastic shelf margin. A Late Permian–earliest Triassic rift pulse has regional expression in the stratigraphic record. A fragmentary paralic to shallow-marine Lower Jurassic succession reflects Early Jurassic thermal subsidence and mild extensional tectonism; this was interrupted by widespread Mid-Jurassic uplift and erosion, and followed by an intense phase of Late Jurassic rifting in some (but not all) parts of the NE Atlantic region. The Cretaceous succession is dominated by thick basinal-marine deposits, which accumulated within and along a broad zone of extension and subsidence between Rockall and NE Greenland. There is no evidence for a substantive and continuous rift system along the proto-NE Atlantic until the Late Cretaceous.

Abstract: Exploration for hydrocarbons in the NE Atlantic mainly focuses on the central eastern margin. The western margin has remained virtually unexplored, with no exploration wells drilled so far. A cost-efficient way to infer the presence of natural hydrocarbons in the poorly explored regions of the NE Atlantic is the application of synthetic aperture radar (SAR). This study presents four areas, the Western Barents Sea Margin, the Irish Atlantic Margin, East Greenland and Jan Mayen, where clustered oil-slick data indicate possible active oil seepage. The eastern margin of the NE Atlantic contains numerous oil-slick observations, but along the western margin the number of observations is limited, partly due to a persistent sea-ice coverage. Based on the tectonostratigraphic setting, it is suggested that Triassic and Jurassic source rocks are the most likely candidates for the generation of seeps in the areas studied. Near Jan Mayen and East Greenland, Cenozoic source rocks could also be present. SAR data are a useful tool in an early stage of exploration, but further work is needed to improve the understanding of the subsurface below the observed oil slicks in the NE Atlantic to determine the origin of the seepage.

Abstract: Permian rugose corals underwent evolutionary episodes of assemblage changeover, biogeographical separation and extinction, which are closely related to geological events during this time. Two coral realms were recognized, the Tethyan Realm and the Cordilleran–Arctic–Uralian Realm. These are characterized by the families Kepingophyllidae and Waagenophyllidae during the Cisuralian, Waagenophyllidae in the Guadalupian and the subfamily Waagenophyllinae in the Lopingian, and the families Durhaminidae and Kleopatrinidae during the Cisuralian and major disappearance of colonial and dissepimented solitary rugose corals from the Guadalupian to the Lopingian, respectively. The development of these coral realms is controlled by the geographical barrier resulting from the Pangaea formation. According to the changes in the composition and diversity of the Permian rugose corals, a changeover event might have occurred at the end-Sakmarian and is characterized by the mixed Pennsylvanian and Permian faunas to typical Permian faunas, probably related to a global regression. In addition, three extinction events are present at the end-Kungurian, the end-Guadalupian and the end-Permian, which are respectively triggered by the northward movement of Pangaea, the Emeishan volcanic eruptions and subsequent global regression, and the global climate warming induced by the Siberian Traps eruption.