The role of crustal contamination in magma evolution of Neoproterozoic metaigneous rocks from Southwest Svalbard

• Neoproterozoic metavolcanics from Wedel Jarlsberg Land and Nördenskiold Land, Svalbard trace magma-crust interaction. The crustal assimilants change geographically reflecting the depositional environment of sedimentary crust. metatuffs have mechanically assimilated shales during eruption. Late metavolcanic rocks occur along Southwest coast Svalbard. protoliths Nordenskiöld are mainly diabase, basalt felsic tuff tholeiitic affinity associated with continental magmatism. We investigate magma evolution paying particular attention to processes interaction assess potential sources contamination. These goals achieved by employing element geochemistry, as well Sr Nd isotope geochemistry. Metavolcanic South (Orvindalen Werenskiöldbreen) higher LREE, LILE Th compared North (Nordenskiöld Land), which relatively enriched in Sr. Incompatible ratios like Th/La, Th/Nb, La/Nb, Th/Yb Nb/Yb also decrease North. 143 Nd/ 144 (635 Ma) ranges 0.511396 0.512356 increases For isotopes, show a wide range, however we observe 87 Sr/ 86 0.70407–0.73043 0.70410–0.71028. Energy Constrained – Assimilation Fractional Crystallization (EC-AFC) modelling indicates that extent contamination is highest South. Additionally suggests fractional crystallization assimilation granulite or amphibolite followed shale for mixtures carbonate contributed. This geographical pattern reflects upper metasedimentary sequences, where phyllites common carbonates more Land). Density contrasts impermeable layers within crust would likely acted barriers ascending magma, forcing it stall providing opportunities