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USGS · 70013335

Geochronological and isotopic evidence for early Proterozoic crust in the eastern Arabian Shield

J. S. Stacey·C. E. Hedge
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Abstract

We report zircon U-Pb, feldspar common Pb, whole-rock Sm-Nd, and Rb-Sr data from sample Z-103, a fine-grained granodiorite from the Jabal Khida region of the Saudi Arabian Shield (lat 21°19′N; long 44°50′W). The measurements yield conclusive evidence for continental crust of early Proterozoic age (∼1,630 Ma) at that locality. Furthermore, lead-isotope data indicate an even earlier, perhaps Archean, crustal history for the source of the lower Proterozoic rocks.

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J. S. Stacey, C. E. Hedge. 1984. Geochronological and isotopic evidence for early Proterozoic crust in the eastern Arabian Shield. https://doi.org/10.1130/0091-7613(1984)12%3C310%3Agaiefe%3E2.0.co%3B2

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