佛子岭岩群中的晋宁期深成岩带及其构造含意

Jinningian Plutonic Belt in the Foziling Group and Its Tectonic Implication

在北淮阳带东段,原卢镇关岩群小溪河组火山—深成杂岩是最主要的岩浆活动带。作者们在追索北秦岭加里东期岛弧东延的过程中,对该火山—深成岩带北部四个侵入佛子岭岩群的变形花岗岩测定了单颗粒锆石U-Pb年龄,所得结果为744±9Ma和665±39Ma,属震旦纪,讨论了由此测定结果产生的佛子岭岩群的时代和对比、大别地块的构造归属以及晋宁期的构造环境和演化顺序等问题。

The metavolcanic-plutonic complex, which were originally attributed to the Xiaoxihe Formation of the Luzhenguan Group, are most obvious magmatism zone in the eastern section of the north Huaiyang belt in the Dabie orogen. In the process of tracing the eastward extension of the Caledonian arc system in the northern Qinling belt, the authors dated zircon U-Pb ages for four metagranites, situated in the north part of the mag-matic zone and intruded into the Foziling Group. The results are 744±9 Ma and 665±39 Ma respectively, all belonging to the Sinian period. The paper also discusses the geological age and correlation of the Foziling Group, the tectonic affinity of the Dabie Block and the tectonic setting and evolutionary sequence of the Jinning Age.