Abstract Field relationships and new U–Pb geochronology data indicate a temporal link between the diverse high-K mafic–intermediate magmas of the Ossa–Morena Zone (OMZ). Ages of c. 338–335 Ma for the Vale de Maceiras gabbro and the Campo Maior microdiorite and quartz-diorite indicate that plutonism took place during a Variscan extensional D 2 deformation event in the OMZ. The syntectonic nature of the Vale de Maceiras pluton is attested to by the orientation of intrusive contacts, magmatic foliation and the growth of contact metamorphic minerals in relation to the Variscan extensional D 2 foliation. The Campo Maior microdiorite, quartz-diorite and orthomigmatites are temporally linked to high-temperature mylonitic gneisses formed simultaneously with the Variscan extensional D 2 deformation event. The geochemical features of the Vale de Maceiras and Campo Maior mafic–intermediate rocks show an affinity with the sanukitoid series. This finding suggests that the observed geochemical variability, from tholeiitic to calc-alkaline and sanukitoid, in the Visean OMZ plutonic rocks ( c. 349–335 Ma) may have been inherited from partially melted mantle domains that were previously contaminated by crustal melts during subduction.

Abstract We present the results of U–Pb dating of zircons of two Late Permian igneous rocks from the Dun Mountain–Maitai and Brook Street terranes of New Zealand's South Island. A conglomerate clast of hornblende diorite from the Early–Middle Triassic Stephens Subgroup, Maitai Group, gives an age of 251.1 ± 1.6 Ma. A sample of hypabyssal andesite–microdiorite (Weetwood Formation) that intrudes the Late Permian Productus Creek Group of the Brook Street Terrane gives an age of 258.8 ± 7.9 Ma. The intermediate and subalkaline geochemistry of the two samples is not distinctive of specific tectonic settings, but their ages match plutons of the I-type, subduction-related Longwood Suite of the nearby Median Batholith. Assuming that correlation with the Longwood Suite is correct, the Weetwood sample increases the known areal extent of intrusion of the Longwood Suite; and the Stephens Subgroup Formation clast is consistent with a detrital link between Gondwana and the Dun Mountain–Maitai Terrane by the Middle Triassic. However, because of uncertainties regarding the timing of magmatism along other parts of the Gondwana margin, the data in this paper do not establish any specific provenance links.