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对采自鲁西雁翎关地区泰山群的三套23件全岩和分离矿物样品进行了Rb-Sr和K-Ar研究。任家庄组(或太平顶组)三组混合岩全岩样品给出不同的等时线,它们的年龄和初始比分别是2474±353Ma和0.7014±0.0019,1841±266Ma和0.7023±0.0006,1544±117Ma和0.7047±0.0006;侵入任家庄组的伟晶岩的一件全岩和三件分离矿物给出等时线年龄2408±69Ma和初始比0.7331±0.0093,该伟晶岩中的一件白云母K-Ar年龄为2295±60Ma;雁翎关组五件斜长角闪岩全岩样品给出等时线年龄2266±118Ma和初始比0.7024±0.0007该组斜长角闪岩的一件分离角闪石的K-Ar年龄为2406±65Ma。上述结果表明,本区2500Ma前后发生了广泛的混合岩化作用,2400Ma前后发生了伟晶岩侵位,这个过程间断性地持续到2300Ma前后;角闪岩相变质作用晚于混合岩化,它发生在2400至2300Ma前后;1900至1100Ma前之间有不止一期变质事件叠加。推测任家庄组原岩老于雁翎关组原岩。
Three Rb-Sr and K-Ar studies were carried out on three sets of 23 rock samples collected from Taishan Group in Yanlingguan area, western Shandong Province. All three sets of mixed rock samples from the Renjiazhuang (or Taiping Formation) group show different isochrons, and their ages and initial ratios are 2474 ± 353Ma and 0.7014 ± 0.0019, 1841 ± 266Ma and 0.7023 ± 0.0006, 1544 respectively ± 117Ma and 0.7047 ± 0.0006. A whole rock and three separate minerals from the pegmatite intruded into the Renjiazhuang Formation gave an isochron age of 2408 ± 69Ma and an initial ratio of 0.7331 ± 0.0093. One of the pegmatites The K-Ar age of muscovite is 2295 ± 60Ma. The whole rock samples of the five amphibolite from Yanlingguan Formation show an isochron age of 2266 ± 118Ma and an initial ratio of 0.7024 ± 0.0007. One of the amphibolite The K-Ar age of the separation amphibole is 2406 ± 65Ma. The above results show that extensive mixing-rocking occurred before and after 2500 Ma in this area, and the pegmatite emplacement took place before and after 2400 Ma. The process lasted intermittently until about 2300 Ma. Amphibolite facies metamorphism later than that of mixed rock Occurred in 2400 to 2300Ma before and after; between 1900 to 1100Ma more than one metamorphic event overlay. Presumably Renlaozhuang original rock Yan Yan Ling Guan group original rock.