Rock mass dating, geochemical characteristics and metallogenic role of Laoliwan granite in Xiaoshan area, west He'nan Province
-
摘要:
豫西崤山老里湾岩体位于华北陆块南缘崤山地区东部，是河南省地矿局地矿一院近年新发现的二长花岗岩体。岩体内部已发现多个矿体，为探寻岩体的形成机制及其与成矿作用的关系，对岩体进行了岩石学、年代学、地球化学及岩体内部矿化特征研究，揭示其形成机制及成矿作用。全岩Rb-Sr定年结果显示，老里湾岩体的侵位时间是149±11Ma。岩体的地球化学特征总体表现为高硅、高铝、富碱、低镁的钾玄质、准铝质-过铝质花岗岩；轻稀土元素富集，重稀土元素亏损，轻、重稀土元素强烈分异；δEu=0.62~0.66，具有中等的负Eu异常，富集Rb、Th、U、K等大离子亲石元素，Nb、Ta、P、Ti等高场强元素亏损；岩体具有中等含量Sr，低Yb、Y，揭示源区除石榴子石外还有斜长石残留；岩体形成于加厚地壳向正常地壳减薄的环境。岩体内部矿化特征具有斑岩型矿床的特征，成矿时代属晚侏罗世，老里湾岩体成矿是豫西地区晚侏罗世成矿事件在崤山东部地区的地质响应。老里湾岩体与成矿作用关系密切，找矿前景较好，岩体周边地区应被视为崤山东部重点找矿靶区之一。
Abstract:Laoliwan granite lies in Xiaoshan area on the southern margin of North China Block. It is a granite body discovered re-cently by Henan Provincial Bureau of Geology and Mineral Resources. This granite mainly consists of adamellite. In this granite body several ore deposits have been found. In order to investigate its formation mechanism and metallogenic role, the authors carried out a study in such aspects as petrology, chronology, geochemistry and mineralization. The formation time of Laoliwan granite is 149 ±11Ma, as shown by Rb-Sr dating. It is highly K calc-alkaline and metaluminous-peraluminous, enriched in silica (SiO2=65.81%~68.52%), aluminum (Al2O3=14.52%~14.75%), alkali (K2O+Na2O=6.52%~7.49%) and depleted in MgO (0.21%~0.73%); LREE is rel-atively enriched while HREE is depleted (ΣLREE/ΣHREE=15.69~16.38), with medium negative Eu anomalies (δEu=0.63~0.66). In addition, it is rich in large ion lithophile elements, such as K, U, and Th, poor in high field elements, such as Nb, Ta, P and Ti, and contains medium Sr (265×10-6~415×10-6, averagely 315×10-6), low Y (14.7×10-6~18.8×10-6, averagely 16.7×10-6) and Yb (1.14×10-6~1.37×10-6, averagely 1.26×10-6), suggesting it was formed during the transition from thickened crust to normal crust, with garnet and plagioclase relics. The inner mineralization is similar to feature of porphyry deposits and its mentallogenic age is Late Jurassic. Its metallogenic role is a geological response to the Late Jurassic mineralization event in Yuxi area. So the Laoliwan granite has a close relationship with mentallization. The ore-searching prospect is good, and the area around Laoliwan granite should be con-sidered to be one of the prospecting targets in the east Xiaoshan region.
-
Key words:
- Laoliwan granite /
- Rb-Sr dating /
- geochemistry /
- Xiaoshan
-
-
表 1 豫西崤山老里湾岩体Rb-Sr同位素组成结果
Table 1. Rb-Sr isotope data of the Laoliwan granite in Xiaoshan region
样品号 Rb/10-6 Sr/10-6 87Rb/86Sr 87Sr/86Sr 2σ LLW-① 236 371 1.8390 0.711440 0.000012 LLW-② 219 289 2.1898 0.712208 0.000014 LLW-③ 245 304 2.3286 0.712061 0.000011 LLW-④ 222 251 2.5546 0.712948 0.000013 
下载: 导出CSV
表 2 豫西崤山老里湾岩体主量元素分析结果
Table 2. Major element analyses of the Laoliwan granite in Xiaoshan area
% 样品号 SiO2 TiO2 Al2O3 Fe2O3 FeO MnO MgO CaO Na2O K2O P2O5 烧失量 总和 LLW-① 66.72 0.33 14.52 1.01 1.43 0.10 0.84 2.57 0.61 6.88 0.16 4.60 99.77 LLW-② 65.81 0.32 14.60 1.83 0.95 0.10 0.82 2.97 0.57 6.61 0.15 5.14 99.87 LLW-④ 68.52 0.33 14.80 2.29 0.50 0.34 0.66 1.38 0.57 6.39 0.16 3.97 99.91 LLW-⑦ 67.87 0.33 14.75 2.42 0.18 0.08 0.29 2.62 0.59 6.13 0.16 4.54 99.96 LLW-⑧ 66.20 0.34 14.67 1.94 0.20 0.09 0.40 4.04 0.56 5.96 0.16 5.38 99.93
下载: 导出CSV
表 3 豫西崤山老里湾岩体微量和稀土元素分析结果
Table 3. Trace element and rare earth element analyses of the Laoliwan granite in Xiaoshan area
10-6 样品号 Mo Zn W Cu Co V Cr Rb Ba Th U Ta LLW-① 1.24 292 1.76 9.19 3.43 32.6 2.54 311 1795 17.4 2.03 1.56 LLW-② 0.763 443 2.36 0.778 3.4 34.6 3.15 272 2158 18.6 2.24 1.73 LLW-④ 1.56 >5000 2.66 2.01 3.34 31.4 2.02 266 1942 17.8 2.82 1.54 LLW-⑦ 4.56 350 2.07 2.85 2.57 32.6 3.21 260 1700 18.6 1.75 1.64 LLW-⑧ 2.11 357 1.95 1.26 2.35 32.1 2.07 274 1643 17.9 1.70 1.72 样品号 Nb Ce Pb Sr Zr Hf Dy Y La Ce Pr Nd LLW-① 26.3 87.3 270 415 134 4.03 2.46 16.9 48.1 87.3 10.8 34.8 LLW-② 26.9 87.9 348 340 158 4.65 2.69 17.8 48.9 87.9 10.9 35.5 LLW-④ 25.4 84.2 219 265 126 3.83 2.41 15.7 46.4 84.2 10.5 33.4 LLW-⑦ 27.3 87.7 67 266 148 4.33 2.63 18.8 49.3 87.7 10.7 34.8 LLW-⑧ 27.3 82.5 79.6 293 141 4.22 2.30 14.7 45.8 82.5 10.3 34.5 样品号 Sm Eu Gd Tb Dy Ho Er Tm Yb Lu （La/Yb）N δEu LLW-① 5.07 1.04 5.02 0.62 2.46 0.41 1.25 0.20 1.24 0.18 27.82 0.63 LLW-② 5.11 1.10 5.13 0.65 2.69 0.47 1.35 0.22 1.37 0.20 25.60 0.66 LLW-④ 4.86 0.99 4.80 0.62 2.41 0.42 1.27 0.21 1.26 0.18 26.41 0.63 LLW-⑦ 5.08 1.01 4.96 0.66 2.63 0.48 1.32 0.22 1.32 0.19 26.79 0.62 LLW-⑧ 4.77 0.98 4.95 0.60 2.30 0.39 1.19 0.19 1.14 0.17 28.82 0.62
下载: 导出CSV
-
[1] Liang T, Bai F J, Lu R, et al. LA-ICP-MS zircons dating of Baishiya body in xiao Mountain, west Henan Province, and its geologic implication[J]. Acta Geologiacal Sinica, 2013, 87(7):722-725. https://www.researchgate.net/institution/Chinese_Academy_of_Geological_Sciences/publications
[2] 胡浩, 李建威, 邓晓东.洛南-卢氏地区与铁铜多金属矿床有关的中酸性侵入岩锆石U-Pb定年及其地质意义[J].矿床地质, 2011, 30(6):979-1001. http://www.cnki.com.cn/Article/CJFDTOTAL-KCDZ201106003.htm
[3] 卢仁, 梁涛, 卢欣祥, 等.豫西崤山后河岩体LA-ICP-MS锆石U-Pb定年及其地质意义[J].地质调查与研究, 2013, 36(4):263-270. http://www.cnki.com.cn/Article/CJFDTOTAL-QHWJ201304004.htm
[4] 卢仁, 梁涛, 卢欣祥, 等.豫西崤山龙卧沟岩体锆石U-Pb年代学、地球化学特征及地质意义[J].中国地质, 2014, 41(3):756-772. http://www.cnki.com.cn/Article/CJFDTOTAL-DIZI201403006.htm
[5] 梁涛, 卢仁.豫西崤山小妹河岩体LA-ICP-MS锆石U-Pb定年、地球化学特征及地质意义[J].地质通报, 2015, 34(8):1526-1540. http://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD201508012.htm
[6] 河南省地质矿产局.河南省区域地质志[M].北京:地质出版社, 1989:1-772.
[7] 罗铭玖, 黎世美, 卢欣祥, 等.河南省主要矿产的成矿作用及矿床成矿系列[M].北京:地质出版社, 2000:1-125.
[8] 李磊, 孙卫志, 孟宪锋, 等.华北陆块南缘崤山地区燕山期花岗岩类地球化学、Sr-Nd-Pb同位素特征及其地质意义[J].岩石学报, 2013, 29(8):2635-2652. http://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201308002.htm
[9] Sun S S, Mc Donough W F. Chemical and isotopic systematics of oceanic basalts:Implications for mantle composition and processes[C]//Saunders A D, Norry M J. Magmatism in the Ocean Basin. Geological Society of London Special Publication, 1989, 42:313-345.
[10] 李铁钢, 武广, 陈毓川, 等.豫西银家沟杂岩体年代学、地球化学和岩石成因[J].岩石学报, 2013, 29(1):46-66. http://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201301005.htm
[11] 毛景文, 谢桂青, 张作衡, 等.中国北方中生代大规模成矿作用的期次及其地球动力学背景[J].岩石学报, 2005, 21(1):169-188. http://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200501018.htm
[12] 王义天, 叶会寿, 叶安旺, 等.小秦岭文峪和娘娘山花岗岩体锆石SHRIMP U-Pb年龄及其意义[J].地质科学, 2010, 45(1):167-180. http://www.cnki.com.cn/Article/CJFDTOTAL-DZKX201001016.htm
[13] 张旗, 王焰, 熊小林, 等.埃达克岩与花岗岩:机遇与挑战[M].北京:中国大地出版社, 2008:1-178.
[14] 张旗, 金惟俊, 李承东, 等.再论花岗岩按照Sr-Yb的分类:标志[J].岩石学报, 2010, 26(4):985-1015. http://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201004002.htm
[15] Wang Q, Xu J F, Jian P, et al. Petrogenesis of adakitic porphyries in an extensional tectonic setting, Dexing, South China:Implications for the genesis of porphyry copper mineralization[J]. Journal of Petrology, 2006, 47:119-144.
[16] 吴福元, 葛文春, 孙德有. 埃达克质岩的概念、识别标志及其地质意义[C]//肖庆辉, 邓晋福, 马大锉, 等. 花岗岩研究思维与方法. 北京: 地质出版社, 2002: 172-191.
[17] 葛小月, 李献华, 陈志刚, 等.中国东部燕山期高Sr低Y型中酸性火成岩的地球化学特征及成因:对中国东部地壳厚度的制约[J].科学通报, 2002, 47(6):474-450. http://www.cnki.com.cn/Article/CJFDTOTAL-KXTB200206021.htm
[18] 高昕宇, 赵太平, 高剑峰, 等.华北陆块南缘小秦岭地区早白垩世埃达克质花岗岩的LA-ICP-MS锆石U-Pb年龄、Hf同位素和元素地球化学特征[J].地球化学, 2012, 41(4):302-319. http://www.cnki.com.cn/Article/CJFDTOTAL-DQHX201204002.htm
[19] 张旗, 王焰, 钱青, 等.中国东部燕山期埃达克岩的特征及其构造-成矿意义[J].岩石学报, 2001, 17(2):236-244. http://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200102007.htm
[20] 张国伟, 张本仁, 袁学诚, 等.秦岭造山带与大陆动力学[M].北京:科学出版社, 2001:1-855.
[21] Meng Q R, Zhang G W. Geologic framework and tectonicevolution of the Qinling orogen, central China[J]. Tectonophysics, 2000, 323(3/4):183-196.
[22] 王清晨, 孙枢, 李继亮, 等.秦岭的大地构造演化[J].地质科学, 1989, (2):129-l42. http://www.cnki.com.cn/Article/CJFDTOTAL-DGYK199704003.htm
[23] 陈海泓, 侯泉林, 肖文交.中国碰撞造山带研究[M].北京:海洋出版社, 1999:224-232.
[24] 任纪舜.论中国大陆岩石圈构造的基本特征[J].中国区域地质, 1991, 10(4):289-293. http://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD199104000.htm
[25] 赵越, 杨振宇, 马醒华.东亚大地构造发展的重要转折[J].地质科学, 1994, 29(2):105-119. http://www.cnki.com.cn/Article/CJFDTOTAL-DZKX402.000.htm
[26] 卢欣祥.秦岭花岗岩揭示的秦岭构造演化过程——秦岭花岗岩研究进展[J].地球科学进展, 1998, 13(2):213-214. http://www.cnki.com.cn/Article/CJFDTOTAL-DXJZ802.018.htm
[27] 洪大卫, 王涛, 童英, 等.华北地台和秦岭-大别-苏鲁造山带的中生代花岗岩与深部地球动力学过程[J].地学前缘, 2003, 10(3):231-256. http://www.cnki.com.cn/Article/CJFDTOTAL-DXQY200303034.htm
[28] Maruyama S, Isozaki Y, Kimura G, et al. Paleogeographic maps of the Japanese Islands:Plate tectonicsynthesis from 752Ma to the present[J]. Island Arc, 1997, 6(1):121-142. doi: 10.1111/iar.1997.6.issue-1
[29] 武广, 陈毓川, 李宗彦, 等.豫西银家沟硫铁多金属矿床流体包裹体和同位素特征[J].地质学报, 2013, 87(3):354-376. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201303007.htm
[30] 武广, 陈毓川, 李宗彦, 等.豫西银家沟硫铁多金属矿床Re-Os和40Ar-39Ar年龄及其地质意义[J].矿床地质, 2013, 32(4):809-822.
[31] 毛景文, 郑榕芬, 叶会寿, 等.豫西熊耳山地区沙沟银铅锌矿床成矿的40Ar-39Ar年龄及其地质意义[J].矿床地质, 2006, 25(4):359-369.
[32] 李永峰, 毛景文, 白凤军, 等.东秦岭南泥湖钼矿Re-Os同位年龄及其地质意义[J].地质论评, 2003, 49(6):652-659. http://www.cnki.com.cn/Article/CJFDTOTAL-DZLP200306015.htm
① 河南省地质矿产勘查开发局第一地质矿产调查院. 河南省崤山地区1∶ 5万区域矿产调查报告. 2012.
-
图(5)
表(3)
计量
- 文章访问数: 821
- PDF下载数: 9
- 施引文献: 0