Characteristics and geological implications of the Late Paleozoic post- orogenic Shierzhan granite in the Great Xing' an Range.
Characteristics and geological implications of the Late Paleozoic post- orogenic Shierzhan granite in the Great Xing' an Range.
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发表时间：
2009
影响因子：
1.8
通讯作者：
Sui Zhen;X. Xue
中科院分区：
文献类型：
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作者：
Sui Zhen;X. Xue
石儿站岩体位于中国东北部的大兴安岭，主要由正长花岗岩和二长花岗岩组成。正长花岗岩LA-ICPMS分析获得的锆石U-Pb年龄为298 Ma，表明它是晚古生代岩浆活动的产物。石儿站花岗岩岩石化学特征为高K(K2O4.82%~6.06%)，属钾橄榄岩系列。富LILE(LREE、Rb、Th、K)，亏损HFSE(Nb、Ta、P、Ti)，具有后造山花岗岩特征。认为该岩体可能是兴安、松嫩地块碰撞后造山演化的产物。花岗岩的锆石Hf同位素数据表明，大兴安岭北部兴安地块的地壳生长发生在显生宙，这与额尔古纳地块有很大的不同，显示了新原生界到显生界的地壳形成年龄。因此，兴安地块和额尔古纳地块具有不同的地壳演化史。
The Shierzhan intrusion, located in the Great Xing' an Range of northeastern China, is mainly composed of syenogranite and monzogranite. Zircon U-Pb age obtained by LA-ICP-MS analyses from the syenogranite is 298Ma, suggesting that it is the production of Late Paleozoic magmatic activities. Petrochemically, the Shierzhan granite is characterized by high K (K_2O 4.82%～ 6.06%) , and therefore belongs to shoshonite series. It is enriched in LILE (LREE, Rb, Th, and K) and depleted in HFSE (Nb, Ta, P, and Ti) , showing characteristics of post-orogenic granites. It is proposed that this pluton was likely the product of post-orogenic evolution after the collision of Xing' an and Songnen massifs. Zircon Hf isotopic data of the granite suggests that crustal growth of Xing' an massif in northern Great Xing' an Range occurred in the Phanerozoic, which is much different from that of the Eerguna massif which displays crustal formation age of Neoprotozoic to Phanerozoic. Therefore, the Xing' an and Eerguna massifs have different crustal evolution histories.