| 赵炳新.小兴安岭东南部胜利林场地区晚三叠世A型花岗岩地球化学特征及构造指示意义[J].地质与勘探,2014,50(Z1):1326-1337 |
| 小兴安岭东南部胜利林场地区晚三叠世A型花岗岩地球化学特征及构造指示意义 |
| Geochemical characteristics of the Late Triassic A-type granite in the Shengli forestry centre area, southeastern Xiao Hinggan Ling and their tectonic implications |
| 投稿时间：2014-03-28 修订日期：2014-09-16 |
| DOI： |
| 中文关键词: 晚三叠世花岗岩 A2型花岗岩 后碰撞 伸展拉张 |
| 英文关键词: Late Triassic granite, A2 type granite, post-collision, extensional environment |
| 基金项目:黑龙江省基金项目（编号:HLJKD2008-08）资助 |
|
| 摘要点击次数: 2009 |
| 全文下载次数: 1622 |
| 中文摘要: |
| 小兴安岭东南部胜利林场地区晚三叠世花岗岩位于松嫩地块东缘，东部以嘉荫－牡丹江断裂为界与佳木斯地块相接。晚三叠世花岗岩以二长花岗岩和正长花岗岩为主。它具较高的SiO2（72.51%~78.83%，平均值75.70%）、K2O+Na2O（7.65%~9.84%，平均8.58%）及FeO*/MgO(5.79~24.43，平均值为12.81);较低的CaO（0.1%~0.87%，平均值0.55%）、P2O5(0.01%~0.03%，平均值0.02%);过碱指数AI=mol(Na2O+K2O)/Al2O3（0.82~1.0，平均值0.88）；以上各值同A型花岗岩值相同。δEu=0.11~0.55,平均为0.31，表现中等－较强的Eu负异常。原始地幔标准化蛛网图上，富集Th、La、Ce、Ta和Rb等元素，而Ba、Sr、Nb和Y明显亏损。在A１、A２型花岗岩类的判别图解上，除一个样品外，其它样品均显示了A2(后碰撞)花岗岩特征。暗示晚三叠世A型花岗岩为造山后伸展拉张环境的产物。 |
| 英文摘要: |
| The Shengli forestry centre district is in the southeast of the Xiao Hinggan Ling Mountains. Late Triassic granites in this district are located in the east of the Songnen crustal block, which is bounded by the Jiayin-Mudanjiang fault adjoining the Jiamusi crustal block in east. These Late Triassic granites are comprised of the monzonitic granite and the syenite granite. They have high contents of SiO2 (72.51%~78.83% average of 75.7%), K2O+Na2O (7.65%~9.84%, 8.58%) and FeO*/MgO (5.79~24.43, average 12.81), and low contents of CaO (0.1%~0.87%, average 0.55%) and P2O5 (0.01%~0.03%, average 0.02%). Their alkali index which ranges from 0.82 to 1.0, average 0.88, is identical with the A-type granite. The Eu element exhibits moderate-stronger negative anomalies (δEu=0.11~0.55, average 0.31). It is clear from the preliminary mantle-normalized trace element pattern that the elements of Th, La, Ce, Ta, and Rb are enriched, while Ba, Sr, Nb, and Y are depleted. Except one sample, all the other samples demonstrate characters of the A2 (post-collision) granite implying that this Late Triassic A type granite was produced by an extensional environment of post-orogenesis. |
|
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
