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安基山和铜山铜（钼）矿床为分别位于宁镇山脉弧形构造拐转处和弧形构造中段的两个中型矿床。前者为与燕山晚期花岗闪长斑岩石英闪长玢岩有关的、以斑岩型和矽卡岩型为主的铜（钼）矿床，岩体的单矿物Ｋ－Ａｒ同位素年龄为１２３．１×１０６—１０６．０×１０６ａ，Ｋ－Ａｒ等时线值为１２３．０×１０６ａ；后者为与燕山晚期石英闪长玢岩有关的矽卡岩型铜（钼）矿床，主岩体的Ｋ－Ａｒ同位素年龄为１１７．０×１０６ａ。从安基山铜（钼）矿床的细脉浸染型钼矿石和铜山铜（钼）矿床的浸染状钼矿石中选取了辉钼矿纯样并对其进行了Ｘ射线衍射分析，结果表明：安基山矿床的辉钼矿为２Ｈ１＋３Ｒ型，铜山矿床的辉钼矿为２Ｈ１型。采用同位素稀释－等离子体质谱法测定了辉钼矿中的１８７Ｒｅ和１８７Ｏｓ，并以衰变常数λ（１８７Ｒｅ）＝１．６４×１０－１１ａ－１计算出两矿床内辉钼矿的成矿年龄分别为（１０８±２）×１０６ａ和（１０６±３）×１０６ａ，分别比相关岩体的年龄晚１５×１０６ａ和１１×１０６ａ
The Anji Mountain and Tongshan Copper (Molybdenum) deposit are two medium-sized deposits located respectively in the arc structure turning point and the middle arc structure of Ningzhen Mountain Range. The former is related to late Yanshan granodiorite porphyry-quartz diorite porphyry type and skarn-type copper (molybdenum) deposits, rock mineral K-Ar isotope age of 123 .1 × 106-106.0 × 106a, the K-Ar isochron age is 123.0 × 106a; the latter is skarn type copper (molybdenum) deposit related to late Yanshanian quartz diorite porphyrite, Body K-Ar isotope age of 117.0 × 106a. Pure molybdenite samples were selected from the veinlets of disseminated molybdenum ore from the Anji Mountain copper (molybdenum) deposit and the disseminated molybdenum ore from the copper-copper (molybdenum) deposit and analyzed by X-ray diffraction. The results show that: The molybdenite in Keishan deposit is 2H1 + 3R type and the molybdenite in Tongshan deposit is 2H1 type. 187Re and 187Os in the molybdenite were determined by isotope dilution-mass spectrometry. The decay constants λ (187Re) = 1.64 × 10-11a-1 were used to calculate the mineralization age of molybdenite in the two deposits (108 ± 2) × 106a and (106 ± 3) × 106a, respectively, which are respectively 15 × 106a and 11 × 106a later than those of related rock mass