Geochronoloy and Geochemical Characteristics of Lundu Mafic Rocks in Kuching Area, Sarawak
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摘要: 加里曼丹岛作为南海南部最大的岛屿，处于印度-澳大利亚板块、欧亚板块和菲律宾海板块的汇聚带，具有复杂的构造演化史.西加里曼丹岛古晋地区晚白垩世岩浆作用强烈，虽然该期基性岩分布少，但其成因研究对探讨西加里曼丹晚白垩纪构造演化过程具有重要意义.对古晋地区伦杜基性岩开展了详细的岩石学、年代学和地球化学研究，结果表明，该地区基性岩的岩石组成主要为辉绿岩和含橄榄石辉长岩，其中辉绿岩锆石定年显示其结晶年龄为83.4±0.9 Ma，说明岩体侵位于晚白垩世.岩石具有较为均一的SiO2（52.01%~52.38%），大部分样品具有较低的TiO2含量（0.81%~0.92%），K2O含量（0.37%~0.53%）和较高的Al2O3（14.00%~14.54%）、MgO（7.40%~7.86%）.微量元素分析结果显示具有较低的稀土元素总量（∑REE=43.96×10-6~48.19×10-6），呈LREE轻度富集的平坦型配分模式，富集大离子亲石元素，亏损Nb、Ta和Ti等高场强元素.（87Sr/86Sr）i=0.705 1~0.705 3，εNd（t）=2.1~3.3.综合分析表明，伦杜基性岩来源于受到俯冲沉积物和板片流体交代改造影响的地幔源区，并结合前人数据推测伦杜基性侵入岩形成于古太平洋俯冲格局下的弧后盆地构造背景，可能与中国东南沿海-海南-越南构成一条俯冲带.Abstract: Kalimantan Island is the largest island in the south of South China Sea that has undergone complex tectonic evolution, resulting from convergence of the Indian-Australian, Pacific and Philippine Sea plates. The Kuching area of Kalimantan Island has a series of Late Cretaceous magmatic rocks, but the distribution of basic rocks is less. The petrogenesis of basic rocks is significant to reveal the tectonic framework and evolution history in that period. In this study, it presents new petrographic, geochronological and geochemical data for the Lundu gabbroic pluton in the Kuching area. The basic rocks are predominantly made of dolerite and gabbro. Zircon U-Pb dating result shows that the crystallization age of the gabbro is 83.4±0.9 Ma, suggesting that the basic rocks intruded in the Late Cretaceous. These samples have low SiO2 ranging from 52.01% to 52.38%, K2O from 0.37% to 0.53% and TiO2 ranging from 0.81% to 0.92% with high Al2O3 of 14.00%-14.54% and MgO of 7.40%-7.86%. These samples are geochemically characterized by enrichment of light rare earth elements (LREE) and large-ion lithophile elements (LILE) and flat distribution of heavy rare earth elements (HREE) with light low REE abundance (∑REE=43.96×10-6-48.19×10-6). The representative samples show low initial 87Sr/86Sr ratios (0.705 1 to 0.705 3) and positive εNd(t) values (2.1 to 3.3). Combination of trace elemental and isotopic results suggest that the parental magmas were likely derived from the mantle source modified by subduction-related fluid and sediments in the back-arc basin tectonic setting in the response of the subduction of the Paleopacific plate, and may link with Southeast China, Hainan island and Vietnam.
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Key words:
- Lundu mafic rock /
- LA-ICP-MS zircon U-Pb dating /
- E-MORB /
- back-arc basin /
- subduction of Paleopacific /
- petrology
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图 1 加里曼丹岛所在地理位置图(改自Hall，2012)
Fig. 1. Location of Kalimantan Island (modified from Hall, 2012)
图 2 (a) 加里曼丹岛图；(b)西加里曼丹岛大地构造简图；(c)古晋地区概况及采样点位置
a.改自Breitfeld et al., 2017；b.改自Hennig et al., 2017；c.改自Aftab et al., 2017
Fig. 2. Simplified map of Kalimantan (a), simplified geological map in West Sarawak (b), geological map of Kuching area showing the sampling locations (c)
图 3 伦杜基性岩体野外及镜下特征照片
a.闪长岩脉侵入基性岩体；b.辉绿岩手标本；c.辉绿岩显微照片；d.含橄榄石辉长岩显微照片；Ol.橄榄石；Cpx.单斜辉石；Pl.斜长石
Fig. 3. Field photographs and photomicrographs from the Lundu mafic rocks, Sarawak
图 4 (a) 沙捞越伦杜辉绿岩(17SA-47A1)锆石U-Pb谐和图和(b)锆石稀土元素球粒陨石配分模式图
Fig. 4. Concordia diagram of zircons U-Pb dating from the Lundu mafic rocks (17SA-47A) (a) and chondrite-normalized REE patterns from the Lundu mafic rocks, Kuching (b)
图 5 伦杜基性岩SiO2-K2O+Na2O(a)和Zr-Y判别(b)图解
a据Le Bas et al.（1986）；b据Barrett et al.（1994）；华南内陆基性岩数据来自Wang et al.（2003）；海南岛基性岩数据来自葛小月等（2003）；东南沿海基性岩来自Xie et al.（2006）和Chen et al.（2008）
Fig. 5. Rock classification TAS SiO2-K2O+Na2O diagrams (a) and Zr-Y diagram of the Lundu mafic rocks, Kuching (b)
图 6 伦杜基性岩的球粒陨石标准化稀土元素配分图(a)和原始地幔标准化微量元素蛛网图(b)
用于标准化的球粒陨石和原始地幔数据分别引自Taylor and McLennan（1995）和Sun and McDonough（1989）
Fig. 6. Chondrite-normalized REE pattern (a) and PM-normalized incompatible element spiderdiagram (b) for the Lundu mafic rocks, Kuching
图 7 伦杜基性岩(87Sr/86Sr)-εNd(t)关系图(改自张云等，2019)
Fig. 7. (87Sr/86Sr)i-εNd(t) diagram of the Lundu mafic rocks(modified from Zhang et al., 2019)
图 8 古晋伦杜地区基性岩的(Ta/La)N-(Hf/Sm)N(a)和U/Th-Th判别图解(b)
Fig. 8. Plots of (Ta/La)N-(Hf/Sm)N (a) and U/Th-Th (b) from Lundu mafic samples, Kuching
图 9 (a) 沙捞越伦杜基性岩Ti-Zr判别图解、(b)Zr/Y-Y判别图解、(c)Th/Zr-Nb/Zr和(d)V-Ti/1 000判别图解
数据来源同图 3
Fig. 9. Ti-Zr (a), Zr/Y-Y (b), Th/Zr-Nb/Zr (c), V-Ti/1 000 (d) for the Lundu mafic rocks, Kuching
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Aftab, A.K., Wan, H.A., Meor, H.H., et al., 2017. Tectonics and Sedimentation of SW Sarawak Basin, Malaysia, NW Borneo. Journal of the Geological Society of India, 89(2): 197-208. https://doi.org/10.1007/s12594-017-0584-0 Barrett, T.J., MacLean, W.H., 1994. Chemostratigraphy and Hydrothermal Alteration in Exploration for VHMS Deposits in Greenstones and Younger Volcanic Rocks. In: Lentz, D.R., ed., Alteration and Alteration Processes Associated with Ore-Forming Systems. Shotr Course Notes, 11: 433-467. Ben-Avraham, Z., Uyeda, S., 1973. The Evolution of the China Basin and the Mesozoic Paleogeography of Borneo. Earth and Planetary Science Letters, 18(2): 365-376. https://doi.org/10.1016/0012-821x(73)90077-0 Breitfeld, H.T., Hall, R., Galin, T., et al., 2017. A Triassic to Cretaceous Sundaland-Pacific Subduction Margin in West Sarawak, Borneo. Tectonophysics, 694: 35-56. https://doi.org/10.1016/j.tecto.2016.11.034 Carter, A., Roques, D., Bristow, C., et al., 2001. Understanding Mesozoic Accretion in Southeast Asia: Significance of Triassic Thermotectonism (Indosinian Orogeny) in Vietnam. Geology, 29(3): 211-214. doi: 10.1130/0091-7613(2001)029<0211:UMAISA>2.0.CO;2 Chen, C.H., Lee, C.Y., Lu, H.Y., et al., 2008. Generation of Late Cretaceous Silicic Rocks in SE China: Age, Major Element and Numerical Simulation Constraints. Journal of Asian Earth Sciences, 31(4-6): 479-498. https://doi.org/10.1016/j.jseaes.2007.08.002 Ding, C., Zhao, Z.D., Yang, J.B., et al., 2015. Geochronology, Geochemistry of the Cretaceous Granitoids and Mafic to Intermediate Dykes in Shishi Area, Coastal Fujian Province. Acta Petrologica Sinica, 31(5): 1433-1447(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSXB201505018.htm Dong, C.W., Zhang, D.R., Xu, X.S., et al., 2006. SHRIMP U-Pb Dating and Lithogeochemistry of Basic-Intermediate Dike Swarms from Jinjiang, Fujian Province. Acta Petrologica Sinica, 22(6): 1696-1702(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSXB200606026.htm Feng, G.Y., Liu, S., Niu, X.L., et al., 2018. Geochronology, Geochemistry and Petrogenesis of Early-Middle Permian Mafic Intrusion in Zhangguangcai Range, China. Earth Science, 43(4): 1293-1306(in Chinese with English abstract). Ge, X.Y., Li, X.H., Zhou, H.W., 2003. Geochronologic, Geochemistry and Sr Nd Isotopes of the Late Cretaceous Mafic Dike Swarms in Southern Hainan Island. Geochimica, 32(1): 11-20(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQHX200301001.htm Hall, R., 2012. Late Jurassic-Cenozoic Reconstructions of the Indonesian Region and the Indian Ocean. Tectonophysics, 570-571: 1-41. https://doi.org/10.1016/j.tecto.2012.04.021 Hennig, J., Breitfeld, H.T., Hall, R., et al., 2017. The Mesozoic Tectono-Magmatic Evolution at the Paleo-Pacific Subduction Zone in West Borneo. Gondwana Research, 48: 292-310. https://doi.org/10.1016/j.gr.2017.05.001 Hofmann, A.W., Jochum, K.P., Seufert, M., et al., 1986. Nb and Pb in Oceanic Basalts: New Constraints on Mantle Evolution. Earth and Planetary Science Letters, 79(1-2): 33-45. https://doi.org/10.1016/0012-821x(86)90038-5 Hoskin, P.W.O., Schaltegger, U., 2003. The Composition of Zircon and Igneous and Metamorphic Petrogenesis. In: Hanchar, J.M., Hoskin, P.W.O., eds., Zircon. De Gruyter, Boston, 27-62. Hutchison, C.S., 1975. Ophiolite in Southeast Asia. Geological Society of America Bulletin, 86(6): 797-806. doi: 10.1130/0016-7606(1975)86<797:OISA>2.0.CO;2 Hutchison, C.S., 2005. Geology of North-West Borneo. Elsevier, Amsterdam, 421. Hutchison, C.S., 2010. Oroclines and Paleomagnetism in Borneo and South-East Asia. Tectonophysics, 496(1-4): 53-67. https://doi.org/10.1016/j.tecto.2010.10.008 Hutchison, C.S., Tan, D.N.K., 2009. Geology of Peninsular Malaysia. University of Malaya, Kuala Lumpur. Le Bas, M.J., Le Maitre, R.W., Streckeisen, A., et al., 1986. A Chemical Classification of Volcanic Rocks Based on the Total Alkali-Silica Diagram. Journal of Petrology, 27(3): 745-750. https://doi.org/10.1093/petrology/27.3.745 Li, C.F., Li, X.H., Li, Q.L., et al., 2012. Rapid and Precise Determination of Sr and Nd Isotopic Ratios in Geological Samples from the Same Filament Loading by Thermal Ionization Mass Spectrometry Employing a Single-Step Separation Scheme. Analytica Chimica Acta, 727: 54-60. https://doi.org/10.1016/j.aca.2012.03.040 Li, X., Yang, M., 2002. Movement and Evolution of Crustobody in Kalimantan and Adjacent Areas. Geotectonica et Metallogenia, 26(3): 235-239(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/ http://search.cnki.net/down/default.aspx?filename=DGYK200203002&dbcode=CJFD&year=2002&dflag=pdfdown Liu, Y.S., Hu, Z.C., Gao, S., et al., 2008. In Situ Analysis of Major and Trace Elements of Anhydrous Minerals by LA-ICP-MS without Applying an Internal Standard. Chemical Geology, 257: 34-43. doi: 10.1016/j.chemgeo.2008.08.004 Liu, Y.S., Gao, S., Hu, Z.C., et al., 2010. Continental and Oceanic Crust Recycling-Induced Melt-Peridotite Interactions in the Trans-North China Orogen: U-Pb Dating, Hf Isotopes and Trace Elements in Zircons from Mantle Xenoliths. Journal of Petrology, 51(1-2): 537-571. https://doi.org/10.1093/petrology/egp082 Ludwig, K.R., 2003. Isoplot 3.00: A Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Center Special Publication, Berkeley. Metcalfe, I., 2000. The Bentong-Raub Suture Zone. Journal of Asian Earth Sciences, 18(6): 691-712. https://doi.org/10.1016/s1367-9120(00)00043-2 Metcalfe, I., 2009. Late Palaeozoic and Mesozoic Tectonic and Palaeogeographical Evolution of SE Asia. Geological Society, London, Special Publications, 315(1): 7-23. https://doi.org/10.1144/sp315.2 Nguyen, T.T.B., Satir, M., Siebel, W., et al., 2004. Granitoids in the Dalat Zone, Southern Vietnam: Age Constraints on Magmatism and Regional Geological Implications. International Journal of Earth Sciences, 93(3): 329-340. https://doi.org/10.1007/s00531-004-0387-6 Plank, T., 2005. Constraints from Thorium/Lanthanum on Sediment Recycling at Subduction Zones and the Evolution of the Continents. Journal of Petrology, 46(5): 921-944. https://doi.org/10.1093/petrology/egi005 Qin, S.C., Fan, W.M., Guo, F., et al., 2010. Petrogenesis of Late Mesozoic Diabase Dikes in Zhejiang-Fujian Provinces: Constraints from Ar-Ar Dating and Geochemistry. Acta Petrologica Sinica, 26(11): 3295-3306(in Chinese with Englishi abstract). Sun, S.S., McDonough, W.F., 1989. Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes. Geological Society, London, Special Publications, 42(1): 313-345. https://doi.org/10.1144/gsl.sp.1989.042.01.19 Tan, D.N.K., 1993. Geology of the Kuching Area, West Sarawak, Malaysia. Geological Survey of Malaysia, Report, 16, Kuching. Tang, L.M., Chen, H.L., Dong, C.W., et al., 2010. Late Mesozoic Tectonic Extension in SE China: Evidence from the Basic Dike Swarms in Hainan Island, China. Acta Petrologica Sinica, 26(4): 1204-1216(in Chinese with Englishi abstract). http://www.oalib.com/paper/1475368 Taylor, S.R., McLennan, S.M., 1995. The Geochemical Evolution of the Continental Crust. Reviews of Geophysics, 33(2): 241-265. https://doi.org/10.1029/95rg00262 Wang, J.R., Chen, W.F., Zhang, Q., et al., 2017. Preliminary Research on Data Mining of N-MORB and E-MORB: Discussion on Method of the Basalt Discrimination Diagrams and the Character of MORB's Mantle Source. Acta Petrologica Sinica, 33(3): 993-1005(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSXB201703023.htm Wang, Y.J., Fan, W.M., Guo, F., 2003. Geochemistry of Early Mesozoic Potassium-Rich Diorites-Granodiorites in Southeastern Hunan Province, South China: Petrogenesis and Tectonic Implications. Geochemical Journal, 37(4): 427-448. http://dio.org/10.2343/geochemj.37.427 doi: 10.2343/geochemj.37.427 Wang, Y.J., Zhao, G.C., Fan, W.M., et al., 2007. LA-ICP-MS U-Pb Zircon Geochronology and Geochemistry of Paleoproterozoic Mafic Dykes from Western Shandong Province: Implications for Back-Arc Basin Magmatism in the Eastern Block, North China Craton. Precambrian Research, 154(1-2): 107-124. https://doi.org/10.1016/j.precamres.2006.12.010 Xie, G.Q., Hu, R.Z., Mao, J.W., et al., 2006. K-Ar Dating, Geochemical, and Sr-Nd-Pb Isotopic Systematics of Late Mesozoic Mafic Dikes, Southern Jiangxi Province, Southeast China: Petrogenesis and Tectonic Implications. International Geology Review, 48(11): 1023-1051. https://doi.org/10.2747/0020-6814.48.11.1023 Yan, J.X., 2005. Tectonic Implications of Marine Mesozoic Deposits from Kalimantan and Malay Peninsula. Journal of Tropical Oceanography, 24(2): 26-32(in Chinese with English abstract). http://www.cqvip.com/QK/71135X/201107/15424717.html Zhang, Y., Sun, L.X., Zhang, T.F., et al., 2019. Geochronology, Geochemistry and Its Tectonic Significance of the Early Paleozoic Magmatic Rocks in Northern Langshan, Inner Mongolia. Earth Science, 44(1): 179-192(in Chinese with English abstract). http://www.researchgate.net/publication/332034792_Geochronology_Geochemistry_and_its_Tectonic_Significance_of_the_Early_Paleozoic_Magmatic_Rocks_in_Northern_Langshan_Inner_Mongolia Zhou, D., Liu, H.L., Chen, H.Z., 2005. Mesozoic-Cenozoic Magmatism in Southern South China Sea and Its Surrounding Areas and Its Implications to Tectonics. Geotectonica et Metallogenia, 29(3): 354-363(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DGYK200503010.htm Zong, K.Q., Liu, Y.S., Gao, C.G., et al., 2010. In Situ U-Pb Dating and Trace Element Analysis of Zircons in Thin Sections of Eclogite: Refining Constraints on the Ultra High-Pressure Metamorphism of the Sulu Terrane, China. Chemical Geology, 269(3-4): 237-251. https://doi.org/10.1016/j.chemgeo.2009.09.021 Zong, K.Q., Klemd, R., Yuan, Y., et al., 2017. The Assembly of Rodinia: The Correlation of Early Neoproterozoic (ca. 900 Ma) High-Grade Metamorphism and Continental Arc Formation in the Southern Beishan Orogen, Southern Central Asian Orogenic Belt (CAOB). Precambrian Research, 290: 32-48. doi: 10.1016/j.precamres.2016.12.010 丁聪, 赵志丹, 杨金豹, 等, 2015. 福建石狮白垩纪花岗岩与中基性脉岩的年代学与地球化学. 岩石学报, 31(5): 1433-1447. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201505018.htm 董传万, 张登荣, 徐夕生, 等, 2006. 福建晋江中-基性岩墙群的锆石SHRIMP U-Pb定年和岩石地球化学. 岩石学报, 22(6): 1696-1702. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200606026.htm 冯光英, 刘燊, 牛晓露, 等, 2018. 张广才岭地块早-中二叠世镁铁质侵入岩体的年代学、地球化学及岩石成因. 地球科学, 43(4): 1293-1306. doi: 10.3799/dqkx.2018.721 葛小月, 李献华, 周汉文, 2003. 琼南晚白垩世基性岩墙群的年代学、元素地球化学和Sr-Nd同位素研究. 地球化学, 32(1): 11-20. doi: 10.3321/j.issn:0379-1726.2003.01.002 李旭, 杨牧, 2002. 加里曼丹及邻区壳体的运动与演化. 大地构造与成矿学, 26(3): 235-239. doi: 10.3969/j.issn.1001-1552.2002.03.003 秦社彩, 范蔚茗, 郭锋, 等, 2010. 浙闽晚中生代辉绿岩脉的岩石成因: 年代学与地球化学制约. 岩石学报, 26(11): 3295-3306. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201011012.htm 唐立梅, 陈汉林, 董传万, 等, 2010. 中国东南部晚中生代构造伸展作用: 来自海南岛基性岩墙群的证据. 岩石学报, 26(4): 1204-1216. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201004019.htm 王金荣, 陈万峰, 张旗, 等, 2017. N-MORB和E-MORB数据挖掘: 玄武岩判别图及洋中脊源区地幔性质的讨论. 岩石学报, 33(3): 993-1005. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201703023.htm 颜佳新, 2005. 加里曼丹岛和马来半岛中生代岩相古地理特征及其构造意义. 热带海洋学报, 24(2): 26-32. doi: 10.3969/j.issn.1009-5470.2005.02.004 张云, 孙立新, 张天福, 等, 2019. 内蒙古狼山北部早古生代岩浆岩年代学、地球化学特征及构造意义. 地球科学, 44(1): 179-192. doi: 10.3799/dqkx.2018.305 周蒂, 刘海龄, 陈汉宗, 2005. 南沙海区及其周缘中-新生代岩浆活动及构造意义. 大地构造与成矿学, 29(3): 354-363. doi: 10.3969/j.issn.1001-1552.2005.03.010 -
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