Citation: | WU Songyang, HOU Lin, DING Jun, ZHANG Jinrang, ZHU Sibao. Deep magma evolution in the extensional Youjiang Basin in late Yanshanian period: Evidence from geochemical characteristics of Baiceng ultramafic rock, Guizhou Province[J]. Geological Bulletin of China, 2017, 36(2-3): 445-458. |
The ultramafic rocks in Baiceng area are located on the southwest margin of Yangtze block. There exist multi-stage magmatic activities and quite a few ultramafic rocks in this area. Lots of research work on ultramafic rocks has been done in this area, but some important questions remain unsolved. In this paper, the authors analyzed major elements, minor elements (including REE) and PGE for 11 samples of ultramafic rocks from Baiceng area. The results show that their major elements vary in a narrow range, implying the characteristics of high potassium and low sodium. These rocks are also enriched in LILE (Ba, Sr, Rb), HFSE (Nb) and rare earth elements. The enrichment of LREE forms a right inclined curve, which indicates definite fractionation of REE. The anomalies of Eu and Ce are negative. The total content of platinum group element is low, and the differentiation is not significant. Geochemical characteristics of these ultramafic rocks indicate that the rocks were formed under a tectonic setting of large-scale lithospheric extension in Youjiang Basin. The magma was derived from the mantle with a low degree of partial melting, with garnet and sulfide being left over during the melting. Obvious crustal contamination never happened during the process of magma rising. The crystallization and differentiation level of magma was not high. The fractionation of clinopyroxene and olivine occurred during magma intruding while there was no fractionation of plagioclase.
[1] | 邓晋福, 苏尚国, 周肃, 等.华北地区燕山期岩石圈减薄的深部过程[J].地学前缘, 2003, 10(3):41-50. |
[2] | Su W C, Hu R Z, Xia B, et al. Calcite Sm-Nd isochron age of the Shuiyindong Carlin-type gold deposit, Guizhou, China[J]. Chemical Geology, 2009, 258:269-274. doi: 10.1016/j.chemgeo.2008.10.030 |
[3] | Peter S G, Huang J Z, Li Z P, et al. Sedimentary rock-hosted Au deposits of the Dian-Qian-Gui area, Guizhou, and Yunnan Provinces, and Guangxi District, China[J]. Ore Geology Reviews, 2007, 31:170-204. doi: 10.1016/j.oregeorev.2005.03.014 |
[4] | 朱赖民, 刘显凡, 金景福, 等.滇-黔-桂微细浸染型金矿床时空分布与成矿流体来源[J].地质科学, 1998, 33(4):463-474. |
[5] | 王砚耕, 索书田, 张明发.黔西南构造与卡林型金矿[M].北京:地质出版社, 1994. |
[6] | 陈懋弘, 毛景文, 吴六灵, 等.滇黔桂矿集区微细浸染型金矿成矿年代学研究[J].桂林工学院学报, 2006, 26(3):334-340. |
[7] | 韩至钧, 王砚耕, 冯济舟, 等.黔西南金矿地质与勘查[M].贵阳:贵州科技出版社, 1999. |
[8] | 陈懋弘, 章伟, 杨宗喜, 等.黔西南白层超基性岩墙锆石SHRIMP U-Pb年龄和Hf同位素组成研究[J].矿床地质, 2009, 28(2):240-250. |
[9] | Liu S, Su W C, Hu R Z, et al. Geochronological and geochemical constraints on the petrogenesis of alkaline ultramafic dykes from south-west Guizhou Province, SW China[J]. Lithos, 2010, 114:253-264. doi: 10.1016/j.lithos.2009.08.012 |
[10] | 冯光英, 刘燊, 苏文超, 等.黔西南碱性超基性脉岩的铂族元素地球化学[J].矿物学报, 2010, 30(2):207-214. |
[11] | 陈懋弘, 毛景文, 屈文俊, 等.贵州贞丰烂泥沟卡林型金矿床含砷黄铁矿Re-Os同位素测年及地质意义[J].地质论评, 2007, 53(3): 371-382. |
[12] | 胡瑞忠, 彭建堂, 马东升, 等.扬子地块西南缘大面积低温成矿时代[J].矿床地质, 2007, 26(6):583-596. |
[13] | 刘建中, 邓一明, 刘川勤, 等.水银洞金矿床包裹体和同位素地球化学研究[J].贵州地质, 2006, 23(1):51-56. |
[14] | 贵州省地质调查院.贵州省区域地质志[M].北京:地质出版社, 1994. |
[15] | Zhang X C, Spiro B, Halls C, et al. Sediment-hosted disseminated gold deposit in Southwest Guizhou PRC: Their geological setting and orgin in relation to mineralogical, fluid inclusion, and stable-isotope characteristics[J]. International Geology Review, 2003, 45:407-470. doi: 10.2747/0020-6814.45.5.407 |
[16] | 梅厚钧.峨眉山玄武岩地球化学特征, IGCAS年度报告 (1980-1981)[M].贵阳:贵州人民出版社, 1980. |
[17] | 路远发. GeoKit:一个用VAB构建的地球化学工具软件包[J].地球化学, 2004, 33(5):459-464. |
[18] | McDonough W F, Sun S S. The composition of the earth[J]. Chemical Geology, 1995, 120: 223-230. doi: 10.1016/0009-2541(94)00140-4 |
[19] | Anders E, Grevese N. Abundances of the elements meteoritic and solar[J]. Geochimica et Cosmochimica Acta, 1989, 53(1):197-214. doi: 10.1016/0016-7037(89)90286-X |
[20] | 张成江, 陈友良. 510-1铀矿床垂直分带规律的发现及其成因意义[J].地质与勘探, 2010, 46(4):434-441. |
[21] | 赵振华.微量元素地球化学原理[M].北京:科学出版社, 1997. |
[22] | Sun S S, McDonough 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 Basins. Geological Society Special Publication, 1989, 42:313-345. |
[23] | 孙晓明, 熊德信, 王生伟, 等.云南哀牢山金矿带墨江金镍矿床铂族元素 (PGE) 地球化学及其对矿床成因的制约[J].矿床地质, 2006, 25(4):438-446. |
[24] | Rehkamper M, HallidayA N, Barfod D, et al. Platinum-Group Element Abundance Patterns in different Mantle Environments[J]. Science, 1997, 278:1595-1598 doi: 10.1126/science.278.5343.1595 |
[25] | 张贵山, 温汉捷, 裘愉卓.闽西晚中生代基性岩脉的地球化学研究[J].地球化学, 2004, 3(3):243-253. |
[26] | 张贵山, 温汉捷, 胡瑞忠, 等.闽东南基性岩脉形成的构造应力场地质意义[J].大地构造与成矿学, 2006, 30(2):142-148. |
[27] | 李立兴, 李厚明, 崔艳合, 等.河北高寺台含铬超基性岩杂岩体成岩成矿时代及岩石成因[J].岩石学报, 2012, 28(11):3757-3771. |
[28] | 冯光英, 刘燊, 冯彩霞, 等.吉林红旗岭超基性岩体的锆石U-Pb年龄、Sr-Nd-Hf同位素特征及岩石成因[J].岩石学报, 2011, 27(6): 1594-1606. |
[29] | 吴华, 李华芹, 莫新华, 等.新疆哈密白石泉铜镍矿区基性-超基性岩的形成时代及其地质意义[J].地质学报, 2005, 79(4):498-502. |
[30] | Pearce J A, Norry M J. Petrogenetic implications of Ti, Zr, and Nb variations in volcanic rocks[J]. Contributions to Mineralogy and Petrology, 1979, 69:33-47. doi: 10.1007/BF00375192 |
[31] | Meschede M. A method of discriminat between different types of mid-ocean ridge basalts and continental tholeiites with the Nb-Zr-Y diagram[J]. Chemical Geology, 1986, 56:207-218. doi: 10.1016/0009-2541(86)90004-5 |
[32] | 杜远生, 黄宏伟, 黄志强, 等.右江盆地晚古生代-三叠纪盆地转换及其构造意义[J].地质科技情报, 2009, 28(6):10-15. |
[33] | 曾允孚, 刘文均, 陈洪德, 等.华南右江复合盆地的沉积构造演化[J].地质学报, 1995, 69(2):113-124. |
[34] | 曾允孚, 刘文均, 陈洪德, 等.右江复合盆地的沉积特征及其构造演化[J].广西地质, 1992, 5(4):1-14. |
[35] | 陈洪德, 曾允孚.右江沉积盆地的性质及演化讨论[J].岩相古地理, 1990, 1:28-37 |
[36] | 毛景文, 谢桂青, 李晓峰, 等.华南地区中生代大规模成矿作用与岩石圈多阶段伸展[J].地学前缘, 2004, 11(1):45-55. |
[37] | Chen M H, Mao J W, Li C, et al. Re-Os isochron ages for arsenopyrite from Carlin-like gold deposits in the Yunnan-Guizhou-Guangxi "golden triangle", southwestern China[J]. Ore Geology Reviews, 2015, 64:316-327. doi: 10.1016/j.oregeorev.2014.07.019 |
[38] | Su W C, Hu R Z, Xia B, et al. Calcite Sm-Nd isochron age of the Shuiyindong Carlin-type Au deposit, Guizhou, China[J]. Chemical Geology, 2009, 258:269-274. doi: 10.1016/j.chemgeo.2008.10.030 |
[39] | Taylor S, McLennan S. The Continental Crust: Its Composition and Evolution[M]. New York:Oxford Press, 1985. |
[40] | Hofmann A, Jochum K, Seufert M, et al. Nb and Pb in oceanic basalts: New constraints on mantle evolution[J]. Earth and Planetary Science Letters, 1986, 79(1/2):33-45. |
[41] | Munker C, Pfander J A, Weyer S, et al. Evolution of planetary cores and the earth-moon system from Nb/Ta systematics[J]. Science, 2003, 301(5629):84-87. doi: 10.1126/science.1084662 |
[42] | Rehkamper M, Halliday A N, Barfod D, et al. Platinum-Group Element Abundance Patterns in different Mantle Environments[J]. Science, 1997, 278:1595-1598. doi: 10.1126/science.278.5343.1595 |
[43] | Munker C. Nb/Ta fractionation in a Cambrian arc/back system, New Zealand:source constraints and application of refined ICPMS techniques[J]. Chemical Geology, 1998, 56:207-218. |
[44] | Naldrett A J, Hoffmann E L, Green A H, et al. The composition of Ni-sulfide ores with particular reference to their content of PGE and Au[J]. Canada Mineral, 1979, 17:403-415. |
[45] | 储雪蕾, 李晓林, 徐久华, 等.汉诺坝玄武岩及其地幔橄榄岩、麻粒岩捕掳体的PGE分布特征[J].科学通报, 1999, 44(8):859-863. |
[46] | 赵正, 漆亮, 黄智龙, 等.攀西裂谷南段鸡街碱性超基性岩微量元素和Sr-Nd同位素地球化学及其成因探讨[J].岩石学报, 2012, 28(6):1915-1927. |
[47] | Barnes S J, Naldrett A J, Gorton M P. The orgin of the Fractionation of plartinum-group elements in terrestrial magmas[J]. Chemical Geology, 1985, 53:303-323. doi: 10.1016/0009-2541(85)90076-2 |
[48] | Genc S C, Tuysuz O. Tectonic setting of the Jurassic bimodal magmatism in the Sakarya zone (central and western Pontides), northern Turkey:A geochemical and isotopic approach[J]. Lithos, 2010, 118(1/2):95-111. |
[49] | Eggins S, Rudnick R, McDonough W. The composition of peridotites and their minerals:A laser-ablation ICP-MS study[J]. Earth and Planetary Science Letters, 1998, 154(1/4):53-71. |
[50] | McDonough W F, Stosch H, Ware N. Distribution of the titanium and the rare earth elements between peridotitic minerals[J]. Contributions to Mineralogy and Petrology, 1992, 110(2):321-328. |
[51] | Xu Y G. Distribution of trace element in spinel and garnet peridotites[J]. Science in China (Series D), 2000, 43(2):166-175. doi: 10.1007/BF02878146 |
[52] | Zack T, Foley S, Jenner G. A consistent partition coefficient set for clinopyroxene, amphibole and garnet from laser ablation microprobe analysis of garnet pyroxenites from Kakanui, New Zealand[J]. Neues Jahrbuch Fur Mineralogie Abhandlungen, 1998, 172:23-41. |
[53] | Bodinier J, Merlet C, Bedini R, et al. Distribution of niobium, tantalum, and other highly incompatible trace elements in the lithospheric mantle:The spinel paradox[J]. Geochimica et Cosmochimica Acta, 1996, 60(3):545-550. doi: 10.1016/0016-7037(95)00431-9 |
[54] | Keays R R. The role of komatiitic magmatism and S-saturation in the formation of ore deposits[J]. Lithos, 1995, 34:1-18. doi: 10.1016/0024-4937(95)90003-9 |
Geotectonic divisions and distribution of magmatic rocks in southwestern Guizhou Provence
Geological map of the study area
SiO2-(K2O+Na2O) diagram of ultramafic rocks in Baiceng
Trace element spider diagram and REE patterns of ultramafic rocks in Baiceng
Primitive mantle-normalized PGE patterns for Baiceng ultramafic rocks
Diagrams for discriminating tectonic settings of ultramafic rocks in Baiceng
Diagrams of MgO-Nb/U (a) and Nb/Ta-La/Yb (b) of ultramafic rocks in Baiceng
Diagrams of correlations of MgO versus major elements of ultramafic rocks in Baiceng
Diagrams of La-La/Sm (a) and MgO-Sr (b) of ultramafic rocks in Baiceng
Diagrams of Ni/Cu-Pd/Ir (a) and Pd-Cu/Pd (b) of ultramafic rocks in Baiceng
Diagrams of La/Sm-Sm/Yb of ultramafic rocks in Baiceng