Elemental and Sr-Nd-Pb Isotope Geochemistry of the Florianópolis Dyke Swarm (Paraná Magmatic Province): Crustal Contamination and Mantle Source Constraints

The Florianopolis Dyke Swarm is located in Santa Catarina island, comprising also the adjacent continental area, and belog to the Parana Magmatic Province (PMP). the dyke outcrops in the island are 0.1-70.0 m thick and most of them are coast-parallel (NE-SW trending), with subordinate NW-SE trending. the vast majority of the dykes has SiO2 varying from 50 to 55 wt% and relatively high-Ti (TiO2>3.0wt%) contents and these rocks were divided using the criteria commonly used to distinguish the different magma types identified in the volcanic rocks from the PMP. The Urubicy dykes (Sr>550 ppm) are the most abundant and some of them experienced crustal contamination reaching to 10%, as evidenced by low P2O5/K2O (0,30-0,21), high (Rb/Ba)PM (1.0-2.2), and radiogenic Sr and Pb isotopic composition (87Sr/86Sri = 0.70716-back to 125 ma) and 206Pb/204Pbm up to 19.093. The Pitanga (Sr