Two-billion-year granulites in the late precambrian metamorphic basement along the southern peruvian coast.
نویسندگان
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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ورودعنوان ژورنال:
- Science
دوره 198 4312 شماره
صفحات -
تاریخ انتشار 1977