辽东连山关地区新太古代花岗杂岩SHRIMP U-Pb年龄、Hf同位素组成及地质意义

发布时间：2018-03-13 22:26

本文选题：辽东半岛　切入点：花岗杂岩　出处：《地球科学》2016年12期 　论文类型：期刊论文

【摘要】：辽东本溪连山关花岗杂岩岩体的精细年代学和地球化学的研究匮乏,区域上辽东地区新太古代岩浆活动较少,研究也相对较弱.辽东本溪连山关地区处于铀矿集中区,是内生铀矿床的有利成矿地区.区内铀矿主要赋存于连山关花岗杂岩体与辽河群浪子山组或鞍山群的接触带附近,表明了岩体与铀矿化关系密切.连山关地区浅肉红色正长花岗岩SHRIMP U-Pb年龄为2 512±14Ma,灰白色条痕状二长花岗岩SHRIMP U-Pb年龄为2 510±15Ma,花岗杂岩侵位时代为新太古代.正长花岗岩SiO_2含量为69.28%~72.70%,K_2O含量为6.24%~7.12%,Na_2O含量为2.77%~3.09%,Al_2O_3含量为13.68%~15.92%;二长花岗岩SiO_2含量为65.53%~71.01%,K_2O含量为2.95%~3.90%,Na_2O含量为3.57%~4.23%,Al_2O_3含量为14.13%~14.90%;连山关花岗杂岩含白云母,A/CNK为1.09~1.16(平均1.12),刚玉(C)为1.37~2.28,P_2O_5和SiO_2无负相关关系,表现为高钾的S型花岗岩.稀土总量较高,轻重稀土元素之间强烈分馏,从正铕异常到负铕异常(δEu=3.55~0.36),亏损Nb、Ta、P、Ti等高场强元素,富集Rb、Th、K等大离子亲石元素.锆石ε_(Hf)(t)值为-15.19~-0.47,对应的单阶段Hf模式年龄TDM为2 826~3 400Ma,两阶段Hf模式年龄T_(DM)~C为2 931~3 650Ma.辽东连山关花岗杂岩可能是在高温中压条件下由中太古代和古太古代地壳物质(以变质泥岩和杂砂岩为主)发生深熔作用形成的,可能发生在后碰撞环境,指示华北克拉通各微陆块拼贴完成.
[Abstract]:The detailed geochronology and geochemistry of the Lianshanguan granitic complex in Benxi, Liaodong, are scarce, and the NeoArchean magma activity is less and the study is relatively weak in the area of Liaodong, where the Benxi Lianshanguan area is located in the uranium concentration area. Uranium deposits mainly occur near the contact zone between Lianshanguan granitic complex and the Langzishan formation or Anshan Group of Liaohe Group. The SHRIMP U-Pb age is 2 512 卤14 Ma. SHRIMP U-Pb age is 2 510 卤15 Ma. the granitic emplacement age of granitic complex is NeoArchaean in Lianshanguan area, and the age is 2 512 卤14 Ma.The grayish-white striped monzogranite SHRIMP U-Pb age is 2 510 卤15 Ma.The granitic complex emplacement age is NeoArchaean. The SiO_2 content of the feldspar rock is 69.287.72.70 and the content of Na2O is 6.24. The content of Na2O is 2.77 and 3.09. It is worth 13.686.6815.92; the SiO_2 content of the feldspar granite is 65.5353,71.01and the content of K2O is 2.952.903.90. the content of Al2O3 is 14.131314.90; the Lianshanguan granitic complex has no negative correlation with SiO_2, and the ACNK of the Lianshanguan granitic complex is 1.09ng1.16 (average 1.12o, corundum Con) is 1.372.28P2O5 and has no negative correlation with SiO_2. It is characterized by high potassium S type granite. The total amount of rare earth is relatively high, and the heavy and heavy rare earth elements are fractionated strongly, from the positive europium anomaly to the negative europium anomaly (未 EU ~ (3. 55) ~ 0. 36 ~ 0. 36). Large ion lithophile elements such as RbsThnk are enriched with zircon 蔚 -15.19 ~ 0.47, corresponding single-stage HF model age TDM is 2 826 ~ 3 400 Ma. and two-stage HF model age T _ T is 2 931 ~ 3 650 Ma. the Lianshan Guanguan granitic complex in Liaodong may be derived from Zhongtai granitic complex under high temperature and medium pressure. The ancient and ancient Archean crustal materials (mainly metamorphic mudstone and complex sandstone) were formed by deep melting, It may occur in the post-collision environment, indicating the completion of the collage of the North China Craton microblocks.
【作者单位】：吉林大学地球科学学院;中国地质调查局沈阳地质调查中心;
【基金】：中国地质调查局地质资源大调查项目(No.12120113058800) 国家自然科学基金青年基金项目(No.41501093)
【分类号】：P588.121;P597;P619.14

【相似文献】