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    The Stenshuvud and Taghusa granitoids: new representatives of Mesoproterozoic magmatism in southern Sweden

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    New sites of Mesoproterozoic granitoid magmatism in southern Sweden have been discovered by recent fieldwork and U-P zircon age determination. In the area around Stenshuvud, in eastern Skane, granitic melts were intruded into country-rock gneisses of unknown age at c. 1450 Ma. The 1458 6 Ma Stenshuvud intrusion is composed of several rock varieties including quartz monzonite, tonalite, monzogranite, and late aplites. The Stenshuvud granitoids proper have glomeroporphyritic textures defined by monomineralic aggregations of feldspar or quartz and polymineralic aggregations of amphibole, biotite and magnetite. At 1442+/-9 Ma, the Taghusa granites were intruded along the contact between the Stenshuvud granitoids and the country-rock gneisses. These granites have streaky appearances, which are due to the presence of short, sub-parallel mafic mineral aggregations. The subsequent intrusion of leucogranites as cross-cutting veins and small bodies was the last phase of the entire magmatic event. All these granitoids appear to be co-genetic and belong to a metaluminous to marginally peraluminous, ferro-potassic, high-K calc-alkaline to shoshonitic sequence. Trace elements indicate similar source materials for both principal intrusions. An epsilon(Nd)-value of -0.6 and a T-DM model age of 1.85 Ga indicate involvement of older crustal materials in the generation of the melt(s). The studied granitoids feature both I- and A-type characteristics but are not typical of either type. While the Stenshuvud granitoids were intruded during NE-SW compressional stress that caused shearing an folding, the Taghusa granites are post-compressional and show no solid-state deformation
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