Petrology and palaeotectonic setting of Cretaceous alkaline basaltic volcanismin the Pieniny Klippen Belt (Western Carpathians, Slovakia)

摘要: Occurrences of mafic alkaline volcanics are scattered all around Europe, being mostly related to anorogenic, extensional tectonic environments. While the widespread Cenozoic basalts have been intensively studied and comparatively well-known, their Cretaceous precursors were often associated with Alpine-Carpathian orogenic zones, so genesis geodynamic setting partially obscured by superimposed deformation alteration. We describe a newly discovered body melanephelionites inserted within Upper deep-marine pelagic succession Pieniny Klippen Belt in Western Slovakia. The consists hyaloclastic lavas nephelinitic composition. mineralogical composition geochemical features Vrsatec volcanites correspond melanephelinites. Reconstruction volcanism Alpine-Carpathian-Pannonian realm infers general extensional/rifting regime that ultimately led opening Penninic oceanic rift arms. However, this rifting started as basically passive non-volcanic. Only during later, post-breakup extension phases did slow-spreading ridges develop, which characterized MORB-type (mid-ocean-ridge basin) basaltic volcanism. Alkaline volcanic provinces linear character appear follow continental margins arms opened Jurassic Early Cretaceous. infer resulted from heating partial melting subcontinental mantle lithosphere on peripheries asthenospheric upwellings confined Alpine Tethys. Consequently, regarding debate about plume vs. non-plume origin volcanism, geological data area rather support latter affinity