Previous palynological studies of the Caspian–Black Sea–Mediterranean corridor primarily focused on pollen and spores for paleoecological and chronostratigraphic studies. Until recently, there has been less emphasis on the nonpollen palynomorphs, such as dinoflagellate cysts, algal and fungal spores, and animal remains. New studies of nonpollen palynomorphs in land-locked seas, estuaries, and lakes reported here indicate that they are important markers of salinity, nutrient loading, and human activity, including ballast discharge, farming, and soil erosion. We describe the nonoxidative laboratory processing methods necessary to extract nonpollen palynomorphs from marine- and brackish-water sediment samples. We list 48 nonpollen palynomorphs taxa from 37 surface sediments (including the past millennium) for cores along the salinity gradient from <16‰ off the Danube Delta to >39‰ in the Aegean, Mediterranean, and Red Seas, for two Crimean saline lakes, the Caspian and Aral Seas, and for lakes in Iran and Kazakhstan. The main nonpollen palynomorphs taxa are illustrated and listed systematically to provide a baseline for future collaborative studies among Black Sea corridor palynologists. We outline the biological affinities of some nonpollen palynomorphs and discuss the initial results of the study in terms of what nonpollen palynomorphs may reveal about the history of the salinity in the Black Sea corridor and the impact of humans on soil erosion, plankton production, and harmful algal blooms.

Abstract Subalkaline basalts from NE Egypt represent an episode of magmatism at c . 24 Ma, coincident with widespread eruptive activity in northern Africa. New geochemical data provide insight into the mineralogical and isotopic characteristics of the underlying mantle. The basalts show little geochemical variation, with incompatible trace element abundances similar to those of ocean island basalts. They display fairly smooth primitive mantle-normalized incompatible trace element patterns. Trace element abundances and Sr–Nd–Pb–Hf isotopic signatures are consistent with contributions from two distinct source regions, one similar to the Afar plume and the other located within the metasomatized spinel-facies subcontinental lithosphere. Mixing of melts from these two domains was followed by minor crustal contamination during prolonged ascent or emplacement. Integrating the geochemical data with available tomographic information allows us to develop a framework for understanding mid-Tertiary magmatic activity throughout northern Africa. A model for this widespread volcanism involves ascent of upwelling mantle derived from the margins of the South African Superplume rooted at the core–mantle boundary and/or through small-scale convection at the 660 km discontinuity. Ascent of magmas to the surface was facilitated by pre-existing structures within the lithosphere, including those associated with incipient rifting of the Red Sea. Supplementary material: Mineral chemistry data are available at http://www.geolsoc.org.uk/SUP18483 .

Abstract The Ślęża Ophiolite is one of several thrust-bounded crustal slices dominated by metabasites in the western Sudetes. The apparent field association of serpentinites, gabbros and amphibolitic components led previous workers to consider that this lithological assemblage represented an ophiolite sequence. Fieldwork suggests that the ophiolite is now highly inclined, partly overturned, so that an ophiolitic pseudostratigraphy can be deduced, grading from serpentinites and gabbros in the south to metabasite lavas in the north. The recent discovery of pillow lava structures (at Gozdnica Hill, to the west of Sobótka town) confirms that the volcanic top of the ophiolite lies in the northern section, as might be expected from the ophiolite model. The gabbros have undergone greenschist facies metamorphism with the random development of low-grade amphibole. The volcanic portion of the sequence comprise metamorphosed dolerites and basalts partly within the contact aureole of the Variscan Strzegom-Sobótka granite. Previous work dated plagiogranites associated with the gabbros at about 400–420 Ma (U-Pb zircon ages). Geochemical data suggest that the gabbros are distinct and apparently not comagmatic with the volcanic section of sheeted dykes and lavas. The gabbros, in particular, although very depleted in incompatible elements are dissimilar to supra-subduction zone ophiolites, exhibiting instead N-MORB-like light REE depleted patterns. Depletion is both a feature of the cumulate character of many of the gabbros, as well as a source effect (especially the uniformly low Nb content). The metabasalts and metadolerites, on the other hand, are a well-evolved single comagmatic suite with high incompatible element contents, Zr/Y approximately 3–4, and generally flat to light REE-depleted patterns. The geochemical dichotomy of the plutonic and volcanic segments calls into question a simple interpretation of the body as a single-stage coherent stratiform ophiolite. Chemical comparison with Sudetic metabasites from within the nearby Rudawy-Janowickie and Kacazawa Complexes shows that the Ślęża metabasites have a number of features in common, including the presence of both low-Ti (gabbros) and high-Ti (dykes and lavas) chemical groups. The correlation of the gabbros, dykes and lavas with the low-Ti and high-Ti (Main Series) metatholeiites respectively, seen throughout the Bohemian Massif, as well as the Sudetes, places them within the regional collage of Palaeozoic crustal blocks separated by the Saxothuringian Seaway. Comparison with Bohemian Massif metabasites also indicates that sediment contamination of the Ślęża Ophiolite sources was not an important process and that an enriched plume source played no part in the generation of the ophiolitic melts. The two Ślęża chemical groups were derived from variably depleted asthenospheric mantle sources. Simple modelling suggests that the volcanic segment could have been derived by 10–15% partial melting of a depleted N-MORB source, whereas the plutonic segment represents around 30% partial melting of a more depleted source. To develop varying degrees of depletion in an oceanic environment, the two sources could be related via incremental partial melting of a shallow MORB-type source.