Abstract Late Moscovian–early Gzhelian conodonts occur abundantly in a newly discovered slope section, the Shanglong section, southern Guizhou, South China. The conodont fauna is dominated by P1 elements of Idiognathodus and associated with elements of Swadelina , Streptognathodus and Heckelina . A total of 62 species, including species in open nomenclature, were identified, which are assigned to eight genera. Index conodont species of Middle and Late Pennsylvanian, e.g. I. podolskensis Group, Sw. sp. A, Sw . subexcelsa , Sw . makhlinae , I . heckeli , I . magnificus , I . guizhouensis , H. eudoraensis , I . naraoensis , and H . simulator are all recovered, and their 10 conodont zones are recognized. The richness and abundance of the conodonts throughout the section are analysed. Conodont richness ranges from 1 to 14 and is positively related to conodont abundance (1–379). The composition of conodont elements, i.e. sinistral v. dextral, P1 v. non-P1 and adult v. subadult and juvenile, is presented. The numerical cluster technique is employed to identify four subbiofacies of the slope setting, namely the I . podolskensis , Swadelina , I. swadei–magnificus and Streptognathodus – Heckelina–Idiognathodus subbiofacies.

Abstract This review focuses on the recognition of volcanic ash occurrences in marine sediment cores and on using their appearance and properties to deduce their origin. Widespread marine tephra layers are important marker horizons for both volcanological as well as general geological investigations. We describe ash detection by visual inspection and logging of sediment cores. Ash layer structure and texture, particle morphologies and lithological compositions of primary volcanic deposits are summarized and processes modifying them are discussed, both natural processes acting on and in the seafloor, i.e. erosion and bioturbation, and anthropogenic modifications during drilling/coring and core preparation. We discuss primary emplacement processes of marine fall and flow tephra deposits derived from either subaerial or submarine sources in order to identify distinguishing properties. We also elaborate on processes generating secondary, resedimented volcaniclastic layers such as submarine landslides and shelf erosion as well as fluvial input and ice-rafting, and how they can be distinguished from primary volcaniclastic deposits, which is essential in tephrostratigraphy. Finally, methods of tephra correlation between cores and on-land deposits/volcanoes are illustrated because they allow us to extend the 1D information from single cores to 3D distribution and facies changes of tephras and to bridge the land–sea gap.