Two-billion-year granulites in the late precambrian metamorphic basement along the southern peruvian coast.

نویسندگان

  • B Dalmayrac
  • J R Lancelot
  • A Leyreloup
چکیده

Uranium-lead data indicate that the high-pressure granulitic and charnockitic nuclei within the medium-grade metamorphic complex of the Peruvian coastal area must be related to an orogenic event 2 x 10(9) years ago. As in western Africa and Brazil, this old granulitic basement is reworked by Late Precambrian orogeny. Its presence along the Peru-Chile Trench must be taken into account in interpreting the anomalously high strontium isotopic ratios of recent calc-alkaline volcanism.

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عنوان ژورنال:
  • Science

دوره 198 4312  شماره 

صفحات  -

تاریخ انتشار 1977