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~(40)Ar/~(39)Ar流体包裹体同位素测年法为金矿成矿年龄测定开辟了新的途径。但是,由于次生包裹体的存在及样品中存在过剩氩或氩丢失,常产生复杂的不一致年龄谱,难以获得准确可靠的成矿年龄。本文对豫西崤山地区含金石英脉中的石英和方铅矿样品进行精选,采用阶段升温法测定出了可靠的~(40)Ar/~(39)Ar年龄。~(40)Ar/~(39)Ar等时线线性相关系数>0.99,~(40)Ar/~(39)Ar初始值分别为294.0和297.0,没有过剩氩和氩丢失。测得其全坪年龄分别为130.6±2.6 Ma和127.8±2.8 Ma;等时线年龄分别为133.0±2.7 Ma和126.0±2.5 Ma,不同样品的年龄值相差很小。由此可确定豫西崤山地区金矿的成矿年龄为130±6 Ma,为燕山期。这一年龄值与崤山变质核杂岩内花岗岩的形成年龄(106.0～122.1 Ma,K-Ar法)接近,说明了崤山金矿的形成与燕山期花岗岩浆活动密切相关,金矿找矿工作应围绕燕山期花岗岩这一主导因素开展。
The dating of ~ (40) Ar / ~ (39) Ar fluid inclusions has opened up new avenues for the determination of gold mineralization age. However, due to the existence of secondary inclusions and the presence of excess argon or argon in the sample, complex and sometimes inconsistent age spectra are often produced, making it difficult to obtain accurate and reliable metallogenic age. In this paper, the samples of quartz and galena from the gold-bearing quartz veins in the Yushan area of western Henan were selected, and the reliable ~ (40) Ar / ~ (39) Ar ages were determined by the phase-heating method. The linear correlation coefficient of ~ 40 Ar / ~ 39 Ar et al is> 0.99, and the initial values of ~ 40 Ar / ~ 39 Ar are 294.0 and 297.0, respectively. No excess argon and argon are lost. The average age of the samples was 130.6 ± 2.6 Ma and 127.8 ± 2.8 Ma, respectively. The isochronal ages were 133.0 ± 2.7 Ma and 126.0 ± 2.5 Ma, respectively. It can be confirmed that the mineralization age of the gold deposits in the Wushan area in western Henan is 130 ± 6 Ma, which is the Yanshan period. This age value is close to the age of the granites (106.0-122.1 Ma, K-Ar method) in the Yanshan metamorphic core complex, which shows that the formation of the Yanshan gold deposit is closely related to the Yanshanian granite magmatism. The gold prospecting work Should focus on Yanshan granite the dominant factor to carry out.