Constraints of Parent Magma on Altered Clay Minerals: A Case Study on the Ashes near the Permin-Triassic Boundary in Xinmin Section, Guizhou Province
-
摘要: 目前对于粘土层中伊蒙混层矿物的堆垛结构、单元层含量与岩浆母质及环境条件关系的了解等，仍然十分匮乏.一定沉积环境下火山灰层中粘土矿物组合、以及伊蒙混层堆垛方式精细结构特征，可能记录了沉积(包括成岩作用) 环境对火山物质蚀变产物的影响.采用X射线衍射(XRD)、扫描电子显微镜(SEM)、元素地球化学分析、氧同位素分析方法等方法，对贵州新民深海相二叠系-三叠系(P-T) 界线附近蚀变火山灰层的地球化学特征、粘土矿物精细结构特征等进行了深入研究.结果表明，4个火山灰粘土层均含有2种具有R3结构、不同混层比的伊蒙混层矿物相，且均出现粘土矿物集合体取代原先的火山碎屑颗粒或在颗粒表面生长的现象，粘土矿物形成于沉积-成岩阶段因而其泥质结构被保留；样品XM-5-1和XM-5-2的Fe3+原子数分别为0.16和0.17个且具有明显Eu负异常和较低的K2O含量，而XM-5-3和XM-5-4的Fe3+原子数均为0.14个，说明相对于前2个粘土层，后2个的岩浆母质更加偏向酸性而表现为成岩蚀变程度更强.粘土矿物的氧同位素组成为17.3‰~18.1‰，与常温下蒙脱石与海水的平衡数值相近，表明粘土矿物化学组成与海底成岩蚀变环境有关，而不同火山灰层的粘土矿物学特征则主要取决于岩浆岩母质以及成岩蚀变强度.Abstract: The study on the influence of sedimentary environments on the altered clay mineralogy facilitates accurate stratigraphical correlation using volcanic ashes as marked beds. However, the relationships among the stacking ordering, illite layer contents, parent magma and environmental condition are still poorly known. A case study on altered vocalnic materials near the Permian-Triassic boundary in the Xinmin section, Guizhou province was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), geochemical analysis, and oxygen isotope analysis methods. Results show that all the four volcanic ash layers contain two phases of mixed-layered illite/smectite (I/S) with R3 structure and varied layer contents, and clay mineral aggregates were found having replaced the volcaniclastic particles or have grown on the surfaces of volcaniclastic particles. It can be inferred that clay minerals formed in sedimentary to early diagenesis periods since the materials preserve argillaceous texture when clay minerals were produced. The number of Fe3+ atoms are 0.16 and 0.17 respectively in the samples XM-5-1 and XM-5-2, and 0.14 in both samples XM-5-3 and XM-5-4, indicating that parent magmas of the latter ones were more of meta acid compared with the former two. It is indicative of more intense alteration of the latter two volcanic ash layers, together with the apparent Eu negative anomaly and less K2O contents. Oxygen isotopic composition of the volcanic ashes ranges narrowly from 17.3‰ to 18.1‰, consistent with the equilibrium value between smectite and ocean water at 25 ℃, suggesting that chemical composition of the Xinmin clay minerals is related to conditions of submarine diagenesis alteration since the clay mineralogy of different volcanic ash layer depends on its parent magma and degree of diagenesis alteration.
-
图 2 新民剖面地层及采样位置描述
Fig. 2. Stratigraphic descriptions and sampling horizons of Xinmin section
图 4 新民剖面＜2 μm颗粒大小的粘土矿物混层相XRD拟合图
Fig. 4. Experimental and calculated XRD patterns of < 2 μm clay fractions from Xinmin ashes
图 5 新民火山灰层粘土矿物代表性(样品XM-5-2) 扫描电镜照片
Fig. 5. Representative SEM photographs of clay minerals from Xinmin volcanic ashes (XM-5-2)
图 6 新民剖面火山灰粘土层化学组成的K2O/Al2O3-Na2O/Al2O3关系
Fig. 6. The K2O/Al2O3-Na2O/Al2O3 relations of Xinmin volcanic ash beds
图 7 新民剖面火山灰粘土层微量元素蛛网图
Fig. 7. Primitive mantle and UCC normalized trace element spider diagrams of Xinmin ashes
图 8 新民剖面火山灰粘土层稀土元素蛛网图
Fig. 8. Chondrite-normalized REE distribution pattern of Xinmin volcanic ashes
表 1 新民剖面火山灰粘土矿物化学组成(%) 及晶体化学式
Table 1. Chemical compositions (%) of Xinmin clay minerals and their structural formulae
样品 SiO2 TiO2 Al2O3 Fe2O3 MnO MgO CaO Na2O K2O P2O5 LOI XM-5-1 51.95 0.50 25.06 3.10 0.04 3.39 0.56 0.45 6.24 0.19 8.93 XM-5-2 52.35 0.56 24.87 3.36 0.03 3.34 0.42 0.39 6.40 0.10 8.54 XM-5-3 52.50 0.44 25.30 2.81 0.01 3.36 0.26 0.11 6.82 0.09 8.75 XM-5-4 52.38 1.36 24.86 2.80 0.09 3.44 0.08 0.00 6.59 0.03 8.74 UCC* 65.89 0.50 15.17 4.49 0.07 2.20 4.19 3.89 3.39 0.20 PAAS* 62.80 1.00 18.90 6.50 0.11 2.20 1.30 1.20 3.70 0.16 样品 晶体化学式 XM-5-1 (K0.54Na0.06Ca0.04Mg0.03)(Al1.50Fe0.16Mg0.31Ti0.03)2(Si3.51Al0.49)4O10(OH)2 XM-5-2 (K0.55Na0.05Ca0.03Mg0.05)(Al1.50Fe0.17Mg0.29Ti0.04)2(Si3.53Al0.47)4O10(OH)2 XM-5-3 (K0.58Na0.01Ca0.02Mg0.04)(Al1.53Fe0.14Mg0.30Ti0.03)2(Si3.53Al0.47)4O10(OH)2 XM-5-4 (K0.55Ca0.01Mg0.06)(Al1.55Fe0.14Mg0.29Ti0.02)2(Si3.56Al0.44)4O10(OH)2 注：UCC*和PAAS*据Taylor and McLennan (1985). 
下载: 导出CSV
表 2 新民剖面火山灰层微量元素和稀土元素含量(10-6)
Table 2. Trace element and rare earth element compositions of Xinmin volcanic ashes (10-6)
样品 XM-5-1 XM-5-2 XM-5-3 XM-5-4 UCC* PAAS* Li 15.4 11.4 9.6 11.5 20.0 75.0 Be 5.02 3.83 3.64 4.08 3.00 Sc 14.9 18.4 19.1 35.2 13.6 16.0 V 44.8 19.3 16.3 107.0 107.0 150.0 Cr 6.86 44.30 2.18 6.01 85.00 110.00 Co 13.80 2.09 4.47 23.10 17.00 23.00 Ni 50.4 22.8 11.8 15.6 44.0 55.0 Cu 36.0 14.0 14.3 23.7 25.0 50.0 Zn 103.0 77.6 48.8 42.3 71.0 85.0 Ga 29.2 31.7 30.0 28.8 17.0 20.0 Rb 264 294 293 278 112 160 Sr 49.5 40.1 25.9 29.0 350.0 200.0 Zr 406 483 567 713 190 27 Nb 21.0 30.8 19.0 29.8 12.0 210.0 Cs 7.84 9.49 9.49 11.50 4.60 19.00 Ba 256 240 230 284 550 15 Hf 14.2 14.7 16.4 19.7 5.8 210.0 Ta 2.96 2.66 2.61 2.57 1.00 Pb 48.9 31.0 19.6 18.9 17.0 20.0 Th 63.7 61.2 52.6 49.2 10.7 14.6 U 12.40 11.80 8.25 3.83 2.80 3.10 La 57.3 105.0 62.8 68.0 30.0 38.2 Ce 113 214 157 211 64 80 Pr 15.0 28.5 20.8 25.6 7.1 8.8 Nd 55.6 103.0 73.9 89.9 26.0 33.9 Sm 10.8 18.7 13.0 14.1 4.50 5.55 Eu 1.59 2.25 1.93 2.25 0.88 1.08 Gd 9.92 13.40 9.61 9.08 3.80 4.66 Tb 1.75 2.09 1.63 1.54 0.64 0.77 Dy 10.8 12.6 11.0 11.2 3.50 4.68 Ho 2.08 2.46 2.42 2.60 0.80 0.99 Er 6.10 7.19 7.76 8.43 2.30 2.85 Tm 0.88 1.07 1.18 1.35 0.33 0.41 Yb 5.65 6.78 7.46 9.06 2.20 2.82 Lu 0.84 0.95 1.10 1.36 0.32 0.43 Y 63.8 63.5 67.9 74.7 22.0 27.0 ΣREE 291.52 518.52 371.54 455.64 ΣLREE 253.49 471.92 329.34 411.09 ΣHREE 38.03 46.59 42.20 44.55 ΣLREE/ΣHREE 6.67 10.13 7.80 9.23 注：UCC*和PAAS*据Taylor and McLennan (1985).
下载: 导出CSV
表 3 新民火山灰粘土层氧同位素组成
Table 3. O isotope compositions of Xinmin ashes
样品 矿物名称 δ18OV-SMOW(‰) 沉积相 XM-5-1 ＜2 μm伊蒙混层粘土矿物 17.8 深海相 XM-5-2 ＜2 μm伊蒙混层粘土矿物 17.3 深海相 XM-5-3 ＜2 μm伊蒙混层粘土矿物 17.5 深海相 XM-5-4 ＜2 μm伊蒙混层粘土矿物 18.1 深海相
下载: 导出CSV
-
Agha, M.A., Ferrell, R.E., Hart, G.F., et al., 2013.Mineralogy of Egyptian Bentonitic Clays Ⅱ:Geologic Origin.Clays and Clay Minerals, 61(6):551-565.doi: 10.1346/ccmn.2013.0610608 Cadrin, A.A.J., Kyser, T.K., Caldwell, W.G.E., et al., 1996.Isotopic and Chemical Compositions of Bentonites as Paleoenvironmental Indicators of the Cretaceous Western Interior Seaway.Palaeogeography, Palaeoclimatology, Palaeoecology, 119(3-4):301-320.doi: 10.1016/0031-0182(95)00015-1 Chen, Z.Q., Benton, M.J., 2012.The Timing and Pattern of Biotic Recovery Following the End-Permian Mass Extinction.Nature Geoscience, 5(6):375-383.doi: 10.1038/ngeo1475 Christidis, G.E., 1998.Comparative Study of the Mobility of Major and Trace Elements during Alteration of an Andesite and a Rhyolite to Bentonite, in the Islands of Milos and Kimolos, Aegean, Greece.Clays and Clay Minerals, 46(4):379-399.doi: 10.1346/ccmn.1998.0460403 Christidis, G.E., Huff, W.D., 2009.Geological Aspects and Genesis of Bentonites.Elements, 5(2):93-98.doi: 10.2113/gselements.5.2.93 Deconinck, J.F., Crasquin, S., Bruneau, L., et al., 2014.Diagenesis of Clay Minerals and K-Bentonites in Late Permian/Early Triassic Sediments of the Sichuan Basin (Chaotian Section, Central China).Journal of Asian Earth Sciences, 81:28-37.doi: 10.1016/j.jseaes.2013.11.018 Eberl, D.D., Blum, A.E., Serravezza, M., 2011.Anatomy of a Metabentonite:Nucleation and Growth of Illite Crystals and their Coalescence into Mixed-Layer Illite/smectite.American Mineralogist, 96(4):586-593.doi: 10.2138/am.2011.3682 Fang, Q., Hong, H.L., Chen, Z.Q., et al., 2016.Microbial Proliferation Coinciding with Volcanism during the Permian-Triassic Transition:New, Direct Evidence from Volcanic Ashes, South China.Palaeogeography, Palaeoclimatology, Palaeoecology.doi:10.1016/j.palaeo.2016.06.026 Ferrage, E., Vidal, O., Mosser-Ruck, R., et al., 2010.A Reinvestigation of Smectite Illitization in Experimental Hydrothermal Conditions:Results from X-Ray Diffraction and Transmission Electron Microscopy.American Mineralogist, 96(1):207-223.doi: 10.2138/am.2011.3587 Gao, Q.L., Chen, Z.Q., Zhang, N., et al., 2015.Ages, Trace Elements and Hf-Isotopic Compositions of Zircons from Claystones around the Permian-Triassic Boundary in the Zunyi Section, South China:Implications for Nature and Tectonic Setting of the Volcanism.Journal of Earth Science, 26(6):872-882.doi: 10.1007/s12583-015-0589-9 Gao, W.P., Hong, H.L., Yin, K., et al., 2013.Fine Structure and Their Genetic Significance of Clay Minerals from the Permian-Triassic Boundary, Huaxi Area, Guizhou Province.Earth Science, 38(6):37-46 (in Chinese with English abstract). https://www.researchgate.net/publication/287549463_Fine_structure_and_their_genetic_significance_of_clay_minerals_from_the_Permian-Triassic_boundary_Huaxi_Area_Guizhou_Province Grim, R.E., Güven, N., 1978.Bentonites:Geology, Mineralogy, Properties and Uses.Elsevier, Amsterdam, 256. Hong, H.L., Churchman, G.J., Yin, K., et al., 2014.Randomly Interstratified Illite-Vermiculite from Weathering of Illite in Red Earth Sediments in Xuancheng, Southeastern China.Geoderma, 214-215:42-49.doi:10.1016/j.geoderma.2013.10.004 Hong, H.L., Xie, S.C., Lai, X.L., 2011.Volcanism in Association with the Prelude to Mass Extinction and Environment Change across the Permian-Triassic Boundary (PTB), Southern China.Clays and Clay Minerals, 59(5):478-489.doi: 10.1346/ccmn.2011.0590505 Hu, Z.W., Huang, S.J., Gao, X.Y., et al., 2008.Clay Minerals in the Clay beds near the Permian/Triassic Boundary at Huaying Mountain, Eastern Sichuan, China:Their Types and Origin.Geological Bulletin of China, 27(3):374-379(in Chinese with English abstract). https://www.researchgate.net/publication/286878321_Clay_minerals_in_the_clay_beds_near_the_PermianTriassic_boundary_at_Huaying_Mountain_eastern_Sichuan_China_their_types_and_origin Huff, W.D., 2016.K-Bentonites:A Review.American Mineralogist, 101(1):43-70.doi: 10.2138/am-2016-5339 Kamo, S.L., Czamanske, G.K., Amelin, Y., et al., 2003.Rapid Eruption of Siberian Flood-Volcanic Rocks and Evidence for Coincidence with the Permian-Triassic Boundary and Mass Extinction at 251 Ma.Earth and Planetary Science Letters, 214(1-2):75-91.doi: 10.1016/s0012-821x(03)00347-9 Korte, C., Kozur, H.W., 2010.Carbon-Isotope Stratigraphy across the Permian-Triassic Boundary:A Review.Journal of Asian Earth Sciences, 39(4):215-235.doi: 10.1016/j.jseaes.2010.01.005 Lanson, B., Sakharov, B.A., Claret, F., et al., 2009.Diagenetic Smectite-To-Illite Transition in Clay-Rich Sediments:A Reappraisal of X-Ray Diffraction Results Using the Multi-Specimen Method.American Journal of Science, 309(6):476-516.doi: 10.2475/06.2009.03 Liao, Z.W., Hu, W.X., Wang, X.L., et al., 2016.Volcanic Origin of Clay Stone near the Permian-Triassic Boundary in the Deep Water Environment of the Lower Yangtze Region and Its Implications for LPME.Acta Geologica Sinica, 90(4):785-800(in Chinese with English abstract). Libbey, R.B., Longstaffe, F.J., Flemming, R.L., 2013.Clay Mineralogy, Oxygen Isotope Geochemistry, and Water/Rock Ratio Estimates, Te Mihi Area, Wairakei Geothermal Field, New Zealand.Clays and Clay Minerals, 61(3):204-217.doi: 10.1346/ccmn.2013.0610304 Lu, Q., Lei, X.R., Liu, H.F., 1991.Genetic Types and Crystallochemical Classification of Irregular Illite/Smectite Interstratified Clay Minerals.Acta Mineralogica Sinica, 11(2):97-104(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-KWXB199102000.htm MacRae, N.D., Nesbitt, H.W., Kronberg, B.I., 1992.Development of a Positive Eu Anomaly during Diagenesis.Earth and Planetary Science Letters, 109(3-4):585-591.doi: 10.1016/0012-821x(92)90116-d McCarty, D.K., Sakharov, B.A., Drits, V.A., 2009.New Insights into Smectite Illitization:A Zoned K-Bentonite Revisited.American Mineralogist, 94(11-12):1653-1671.doi: 10.2138/am.2009.3260 Middleton, A.W., Uysal, I.T., Golding, S.D., 2015.Chemical and Mineralogical Characterization of Illite-Smectite:Implications for Episodic Tectonism and Associated Fluid Flow, Central Australia.Geochimica et Cosmochimica Acta, 148:284-303.doi: 10.1016/j.gca.2014.09.035 Reynolds, Jr.R.C., Hower, J., 1970.The Nature of Interlayering in Mixed-Layer Illite-Montmorillonites.Clays and Clay Minerals, 18(1):25-36.doi: 10.1346/ccmn.1970.0180104 Shen, S.Z., Crowley, J.L., Wang, Y., et al., 2011.Calibrating the End-Permian Mass Extinction.Science, 334(60-61):1367-1372.doi: 10.1126/science.1213454 Sheppard, S.M.F., Gilg, H.A., 1996.Stable Isotope Geochemistry of Clay Minerals.Clay Minerals, 31(1):1-24.doi: 10.1180/claymin.1996.031.1.01 Taylor, S.R., McLennan, S.C., 1985.The Continental Crust:Its Composition and Evolution.Blackwell, Oxford, 312. Tian, L., Tong, J.N., Bottjer, D., et al., 2015.Rapid Carbonate Depositional Changes Following the Permian-Triassic Mass Extinction:Sedimentary Evidence from South China.Journal of Earth Science, 26(2):166-180.doi: 10.1007/s12583-015-0523-1 Uysal, I.T., Mutlu, H., Altunel, E., et al, 2006.Clay Mineralogical and Isotopic (K-Ar, δ18O, δD) Constraints on the Evolution of the North Anatolian Fault Zone, Turkey.Earth and Planetary Science Letters, 243(1):181-194. Xie, S.C., Pancost, R.D., Wang, Y.B., et al., 2010.Cyanobacterial Blooms Tied to Volcanism during the 5 m.y.Permo-Triassic Biotic Crisis.Geology, 38(5):447-450.doi: 10.1130/g30769.1 Yan, C.B., Jiang, H.S., Lai, X.L., et al., 2015.The Relationship between the "Green-BeanRock" Layers and Conodont Chiosella timorensisand Implications on Defining the Early-Middle Triassic Boundary in the Nanpanjiang Basin, South China.Journal of Earth Science, 26(2):236-245.doi: 10.1007/s12583-015-0535-x Yin, H.F., Jiang, H.S., Xia, W.C., et al., 2014.The End-Permian Regression in South China and its Implication on Mass Extinction.Earth-Science Reviews, 137:19-33.doi: 10.1016/j.earscirev.2013.06.003 Zhang, N., Jiang, H.S., Zhong, W.L., et al., 2014.Conodont Biostratigraphy across the Permian-Triassic Boundary at the Xinmin Section, Guizhou, South China.Journal of Earth Science, 25(5):779-786.doi: 10.1007/s12583-014-0472-0 Zhang, S.X., Feng, Q.L, Gu, S.Z., et al., 2006.Clay Stone around Deep Water Permian-Triassic Boundary from Guizhou and Guangxi Region.Geological Science and Technology Information, 25(1):9-13(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DZKQ200601001.htm Zhang, S.X., Yu, J.X., Yang, P.Q., et al., 2004.Study on Clayrocks of the Neritic, Littoral and Marine-Terrigenous Facies across the Permian-Triassic Boundary in the Eastern Yunnan and Weastern Guizhou, South China.Journal of Mineralogy and Petrology, 24(4):81-86(in Chinese with English abstract). https://www.researchgate.net/publication/293253054_Study_on_clayrocks_of_the_neritic_littoral_and_marine-terrigenous_facies_across_the_Permian-Triassic_boundary_in_the_Eastern_Yunnan_and_Western_Guizhou_South_China Zhao, T.Y., Feng, Q.L., Liu, R., et al., 2013.Volcanics Characteristics and LA-ICP-MS Zircon U-Pb Ages of Clay Rocks along Dongpan Section of Guangxi.Geological Bulletin of China, 32(9):1402-1409(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-ZQYD201309009.htm 高文鹏, 洪汉烈, 殷科, 等, 2013.贵州花溪P-T界线附近粘土矿物结构及成因意义.地球科学, 38(6): 37-46. http://www.earth-science.net/WebPage/Article.aspx?id=2795 胡作维, 黄思静, 郜晓勇, 等, 2008.川东华蓥山二叠系/三叠系界线附近粘土层中粘土矿物的类型及成因.地质通报, 27(3): 374-379. http://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD200803011.htm 廖志伟, 胡文瑄, 王小林, 等, 2016.下扬子PTB界线深水相区粘土岩的火山成因研究及其对LPME的指示意义.地质学报, 90(4): 785-800. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201604014.htm 陆琦, 雷新荣, 刘惠芳, 1991.不规则伊/蒙混层粘土矿物成因类型及晶体化学分类.矿物学报, 11(2): 97-104. http://www.cnki.com.cn/Article/CJFDTOTAL-KWXB199102000.htm 张素新, 冯庆来, 顾松竹, 等, 2006.黔桂地区深水相二叠系-三叠系界线附近黏土岩研究.地质科技情报, 25(1): 9-13. http://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ200601001.htm 张素新, 喻建新, 杨逢清, 等, 2004.黔西滇东地区浅海、滨海及海陆交互相二叠系-三叠系界线附近粘土岩研究.矿物岩石, 24(4): 81-86. http://www.cnki.com.cn/Article/CJFDTOTAL-KWYS200404015.htm 赵天宇, 冯庆来, 刘嵘, 等, 2013.广西东攀剖面粘土岩的火山岩特征及LA-ICP-MS锆石U-Pb年龄.地质通报, 32(9): 1402-1409. http://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD201309009.htm -
点击查看大图
图(8) / 表(3)
计量
- 文章访问数: 4948
- HTML全文浏览量: 2486
- PDF下载量: 34
- 被引次数: 0
