【摘要】 石桥岩群是一套浅变质的正常沉积碎屑岩 ,同位素地质年龄 ( 6 2 0± 2 2 )Ma。岩石富SiO2 、K2 O、REE ,贫Al2 O3、MnO、Ca、Na2 O、Sr,K2 O/Na2 O、SiO2 /Al2 O3、(La/Yb) N 比值高 ,铕负异常明显 ,表明它是伸展型断陷盆地边缘之河口浅海环境中沉积的稳定型复理式建造。它揭示苏胶造山带在晋宁期造山后的震旦纪开始裂解 ,是Rodinia超大陆震旦纪裂解的组成部分。更多还原

【Abstract】 Shi qiao rock clusters are a suit of shallow metamorphised clastic rocks of normal sedimentation with an isotopic geological age of (620±22) Ma. The rocks are rich in SiO 2, K 2O, REE and poor in Al 2O 3, MnO, Ca, Na 2O, Sr, K 2O/Na 2O, SiO 2/Al 2O 3, and high specific value of (La/Yb) n, europium negative anomaly is evident, showing that it is a stable flysch formation deposited in stream outlets and shallow sea environments around the extended fault basin margin. The formation opened out that Su Jiao orogenic belt began splitting in Sinian period of post Jinning movement and formed the composite part of Rodinia super continental Sinian splitting groups.更多还原