Evidence from the Parana of south Brazil for a continental contribution to Dupal basalts

  title={Evidence from the Parana of south Brazil for a continental contribution to Dupal basalts},
  author={Chris J. Hawkesworth and Marta Silvia Maria Mantovani and Paul N. Taylor and Zenon A. Palacz},
It has been suggested1,2 that the oceanic upper mantle preserves a large scale isotope anomaly, Dupal2, which may be thousands of millions of years old. New Nd-, Pb- and Sr-isotope data on the continental volcanic rocks of the Parana, south Brazil, reveal ‘enriched’isotopic ratios, with 87Sr/86Sr = 0.705−0.716 and εnd = −2.5 to −8, similar to those from other continental flood basalt provinces. Their 207Pb/204Pb ratios are higher than those of mid-ocean-ridge basalts (MORB) at comparable 206Pb… 
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    Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences
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