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赣中变质岩带主要由斜长(云母)变粒岩、十字石榴云母片岩、云母石英片岩夹斜长角闪岩组成。斜长角闪岩Sm-Nd全岩等时线年龄为1113±19Ma,相当于该变质岩带的原岩形成年龄。ε_(Nd)(t)值为2.4±0.1,说明岩浆起源于亏损程度较低的地幔源区:726.6±1.1Ma、403.1±6.4Ma的Rb-Sr等时线年龄表明赣中地区在新元古代末期、加里东期经历了一次强烈的构造变质热作用,其地质、地球化学特征及时代可与浙闽地区陈蔡群、建瓯群进行对比。因此赣中变质岩带并非长期公认的华南加里东褶皱带,应是华夏地块的一部分,这一事实对华南大地构造单元的划分及构造演化具有重要意义。
Ganzhong metamorphic belt is mainly composed of plagioclase amphibolite (mica) granulite, cross pomegranate mica schist, mica-quartz schist clayey amphibolite. The Sm-Nd whole-rock isochron age of the amphibolite is 1113 ± 19Ma, which is equivalent to the protolith age of the metamorphic belt. The value of ε_ (Nd) (t) is 2.4 ± 0.1, indicating that the magma originated from the mantle source areas with a lower degree of depletion: the Rb-Sr isochron ages of 726.6 ± 1.1Ma and 403.1 ± 6.4Ma indicate that the central- In the late ancient period, Caledonian experienced a strong tectono-thermal effect. Its geological, geochemical characteristics and times can be compared with that of Chen Caiqun and Jianou in Zhejiang and Fujian provinces. Therefore, the fact that the metamorphic rock zone in the middle Jiangxi is not a long-recognized southern Caledonian fold belt and should be part of the Cathaysian block is of great significance to the division and tectonic evolution of tectonic units in the South China.