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The Huangtuliang monzonitic granite outcrops on the northern side of the Huangtuliang gold mining district, Chicheng, North Hebei Province. Our predecessors only made isotopic age determination using the K-Ar method. Through LA-MC-ICP-MS zircon U-Pb dating and zircon Hf isotopic composition determination, this study acquired the age of 244.8±2.0 Ma(MSWD=0.57) on the basis of the weighed mean 206Pb/238U ratio, indicating that the Huangtuliang monzonitic granite was formed during the Middle Triassic period, which is the product of Early Indosinian magmatic activities in the region of North Hebei. εHf(t) values vary relatively evenly, within the range of-10.65--14.03, with an average of-12.14. The two-stage evolution model ages, tDM2, vary between 1943 and 2144 Ma, implying that the rock-forming materials of the Huangtiliang monzonitic granite mainly came from the Paleoproterozoic recirculated crustal materials, though a small quantity of enriched-mantle materials would have been involved.
The Huangtuliang monzonitic granite outcrops on the northern side of the Huangtuliang gold mining district, Chicheng, North Hebei Province. Our predecessors only made isotopic age determination using the K-Ar method. Through LA-MC-ICP-MS zircon U-Pb dating and zircon Hf isotopic composition determination, this study acquired the age of 244.8 ± 2.0 Ma (MSWD = 0.57) on the basis of the weighed mean 206Pb / 238U ratio, indicating that the Huangtuliang monzonitic granite was formed during the Middle Triassic period, which is the product of Early Indosinian magmatic activities in the region of North Hebei. εHf (t) values vary relatively evenly, within the range of-10.65--14.03, with an average of -12.14. The two-stage evolution model ages, tDM2, vary between 1943 and 2144 Ma, implying that the rock-forming materials of the Huangtiliang monzonitic granite mainly came from the Paleoproterozoic recirculated crustal materials, though a small quantity of enriched-mantle materials would have been involv ed.