The results of a laser ablation microprobe–inductively coupled by the more widely used samarium–neodymium system (e.g. Dickin, 1995). As a tracer of petrogenetic processes, plasma mass spectrometry Lu–Hf isotope study of zircons in however, Lu–Hf has one important advantage over Sm– 0·93–1·67 Ga rocks from south Norway indicate that early Nd: zircons retain a robust memory of their initial Hf P...