The Quanzigou Mo deposit is located in the western portion of the northern margin of the North China Craton (NCC). The results of molybdenite Re–Os isotopes indicate that the mineralization occurred at 170.8 ± 2.0 Ma. It is coeval with the mineralization-related porphyritic biotite granite pluton and granite porphyry dykes of respectively 170.3 ± 1.1 Ma and 169.3 ± 1.0 Ma (zircon U–Pb ages). Thus, the Quanzigou deposit is confirmed to fill the gap of the regional early Yanshanian (i.e., Early–Middle Jurassic) porphyry Mo deposits in this study. Whole-rock ε_Nd(t) (−12.09 to −9.72; mean = −10.80) and zircon ε_Hf(t) values (−16.28 to −9.23; mean = −12.01) of the Quanzigou granites indicate that they originated from the lower continent crust involving some depleted mantle material. Zircon oxygen fugacity results (f_O2) show that the mineralization-related granites are high magma f_O2 with an average ΔFMQ_Zr (departure from the fayalite–magnetite–quartz oxygen buffer) of +1.1 in the porphyritic biotite granite pluton and an average ΔFMQ_Zr of +1.0 in the granite porphyry dykes, respectively. Because of the relative low-f_O2 of the ancient lower continent crust, the high-f_O2 source might be associated with continuously metasomatic fluids/melts from the high-f_O2 lithospheric mantle, which was metasomatized by the fluids/melts of the preexisting high-f_O2 sediments during the closure of the paleo-Asian Ocean. Therefore, the high-f_O2 granites are formed during the tectonic setting of the post-collisional compression-to-extension transition caused by the continental collision between the Siberian plate and the NCC. Their high-f_O2 characteristics were inherited from the early oceanic crust sediments during the closure of the paleo-Asian Ocean.

泉子沟钼矿床位于华北克拉通（NCC）北缘西部。辉钼矿 Re-Os 同位素结果表明矿化发生在 170.8 ± 2.0 Ma。它与矿化相关的斑状黑云母花岗岩岩体和花岗岩斑岩岩脉分别为 170.3 ± 1.1 Ma 和 169.3 ± 1.0 Ma（锆石 U-Pb 年龄）同时期。因此，本研究证实泉子沟矿床填补了区域早燕山世（即早—中侏罗世）斑岩钼矿床的空白。全岩ε _Nd ( t ) (-12.09 至 -9.72；平均值 = -10.80) 和锆石ε _Hf ( t) 值 (-16.28 至 -9.23; 平均值 = -12.01) 表明它们起源于下大陆地壳，涉及一些枯竭的地幔物质。锆石氧逸度结果 ( f _O2 ) 表明，与矿化相关的花岗岩是高岩浆f _O2，斑状黑云母花岗岩中的平均 ΔFMQ _Zr（从铁橄榄石-磁铁矿-石英氧缓冲层出发）为 +1.1，平均 ΔFMQ花岗岩斑岩岩脉中的_{Zr 分别}为 +1.0。由于古老的下大陆地壳相对低f _O2，高f _O2源可能与来自高f _O岩石圈地幔的连续交代流体/熔体有关，后者在古亚洲洋关闭期间被先前存在的高f _O沉积物的流体/熔体交代。因此，高f _O2花岗岩是在西伯利亚板块与华北克拉通大陆碰撞引起的后碰撞压缩-伸展过渡的构造环境中形成的。它们的高f _O2特征是从古亚洲洋闭合期间早期洋壳沉积物继承而来的。