“…Sardinha basaltic melting is coeval with, and of similar composition to, Paraná (Serra Geral) melting from the southern part of Brazil (Bellieni et al, 1990;Baksi & Archibald, 1997). A northsouth alignment of outcrops from the Parnaíba basin might be caused by minor amounts of rifting parallel to the South Atlantic margin or by pre-existing weaknesses along the Transbrasiliano lineament (Figure 1a n/a n/a n/a n/a n/a n/a n/a n/a LOI (%) 0.25 n/a n/a n/a n/a n/a n/a n/a n/a (Fodor et al, 1990;de Min et al, 2003;Ernesto et al, 2003); open circles show samples from Mosquito Formation that have insufficient trace element data or are too evolved for our purposes (Bellieni et al, 1990;Fodor et al, 1990;de Min et al, 2003;Merle et al, 2011); solid diamonds show samples from Sardinha Formation used in this study (Fodor et al, 1990;Ernesto et al, 2003;da Silva et al, 2017); open diamonds show samples from Sardinha Formation that have insufficient trace element data or are too evolved for our purposes (Bellieni et al, 1990;Fodor et al, 1990;de Min et al, 2003;Ernesto et al, 2003); solid squares show samples from putative Sardinha Formation used in this study (da Silva et al, 2017); solid/dashed line shows Transbrasiliano lineament (Bizzi et al, 2003). (b) Geological map of Parnaíba Basin modified after Bizzi et al (2003).…”