Thus the different tectonic units have different late Archean tectonometamorphic histories. Trace element geochemistry as well as Pb + Nd isotope characteristics of the SMZ are similar to those of the Kaapvaal Craton, with low Th and U concentrations around 2 and 0.7 ppm.
The different tectonic units have distinct late Archean metamorphic histories. The trace element geochemistry and Pb + Nd isotopic composition of the SMZ resemble those of the Kaapvaal Craton, exhibiting low Th and U levels of about 2 and 0.7 ppm.