首页|Nd, Pb, Sr, and O isotopic characterization of Saudi Arabian shield terranes
Nd, Pb, Sr, and O isotopic characterization of Saudi Arabian shield terranes
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
NSTL
New Nd, Sr and O isotopic data for granitoid rocks of the Saudi Arabian Shield are presented together with published Nd, Pb, Sr and O isotopic data and all available geologic and geochronologic information to re-evaluate the terranes defined for the Saudi Arabian part of the Arabian-Nubian Shield. Three groups of terranes are identified: 1) the western arc terranes, 2) the eastern arc terranes, and 3) the Khida terrane. The Khida terrane is the only terrane composed of pre-Neoproterozoic continental crust. The western arc terranes are of oceanic arc affinity, and have the least radiogenic Pb and Sr and most radiogenic Nd isotopic compositions and some of the lowest delta O-18 values of any rocks of the Saudi Arabian Shield. Although some previous studies have characterized the eastern arc terranes as of continental affinity, this study shows that they too are composed of Neoproterozoic oceanic arcs, although their sources have slightly elevated Pb-208/Pb-204, Nd, Sri, and delta O-18 values compared to the western are terranes. These data suggest that either the isotopic composition of the mantle source for the western arc terranes is more depleted than that of the eastern arc terranes or the eastern arc terranes have been mixed with a small amount of cratonic source material, or both.
NSTL
