Geochronology, Geochemistry, and Tectonic Significance of Mid-Cretaceous Andesites in Guangxi and Guangdong

doi:10.19657/j.geoscience.1000-8527.2020.076

Abstract

Abstract:

There are numerous records of Cretaceous magmatism in the coastal Southeast China. Cretaceous andesite is limited in Guangdong and Guangxi, but it may significantly reveal the Late Mesozoic tectonic setting of the northern continental margin of the South China Sea (SCS). In this paper, andesites from Yulin in Guangxi, together with Lianping and Renhua in Guangdong are selected for the study. Based on zircon U-Pb geochronology, petrography and geochemistry, systematic study on the above rock types is carried out for the first time. The results include: (1) The samples are porphyritic with phenocrysts of mainly hornblende, pyroxene and plagioclase, and the groundmass displays andesitic texture with mainly subhedral plagioclase grains; (2) Zircons of Yulin andesite yielded a weighted mean ²⁰⁶Pb/²³⁸U age of (93.38±0.83) Ma, which is younger than the Renhua andesites (zircon U-P age: ca.105 Ma). Therefore, there are many Mid-Cretaceous andesite records in the northern continental margin of SCS; (3) The samples are charactered with high MgO and Mg^#, lower FeO^T/MgO ratios, and are LREE- and LILE-enriched and HFSE-depleted. The high-Mg andesites in Guangdong and Guangxi were formed almost coevally with the adakitic rocks in Hainan Island and Shilu (Guangdong), indicating that the tectonic setting in northern continental margin of SCS differs from that of Zhejiang and Fujian, which was influenced by the Paleo-Pacific subduction. It is concluded that tectonics of the northern SCS margin may have been influenced by the Late Mesozoic Neo-Tethyan ridge subduction.

Key words: northern South China Sea margin, Mid-Cretaceous, high-Mg andesite, Neo-Tethyan ridge subduction

CLC Number:

LIU Yang, FANG Nianqiao, QIANG Menglin, JIA Lei, SONG Chaojie. Geochronology, Geochemistry, and Tectonic Significance of Mid-Cretaceous Andesites in Guangxi and Guangdong[J]. Geoscience, 2021, 35(04): 968-980.

Figures/Tables 9

References 85

[1]	LI J H, ZHANG Y Q, DONG S W, et al. Cretaceous tectonic evolution of South China: A preliminary synjournal[J]. Earth-Science Reviews, 2014, 134:98-136. DOI URL
[2]	LI Z, QIU J S, YANG X M. A review of the geochronology and geochemistry of Late Yanshanian (Cretaceous) plutons along the Fujian coastal area of southeastern China: Implications for magma evolution related to slab break-off and rollback in the Cretaceous[J]. Earth-Science Reviews, 2014, 128:232-248. DOI URL
[3]	毛建仁, 高桥浩, 厉子龙, 等. 中国东南部与日本中—新生代构造-岩浆作用对比研究[J]. 地质通报, 2009, 28(7):844-856.
[4]	CHEN C H, LEE C Y, LU H Y, et al. Generation of Late Cretaceous silicic rocks in SE China: Age, major element and numerical simulation constraints[J]. Journal of Asian Earth Sciences, 2008, 31(4/5/6):479-498. DOI URL
[5]	邱检生, 王德滋, 周金城. 福建永泰云山晚中生代双峰式火山岩的地球化学及岩石成因[J]. 岩石矿物学杂志, 1999, 18(2):97-107.
[6]	蒋英, 梁新权, 梁细荣, 等. 粤北仁化白垩纪安山玢岩锆石年代学、地球化学和岩石成因研究[J]. 大地构造与成矿学, 2015, 39(3):481-496.
[7]	耿红燕, 徐夕生, O’REILLY S Y, 等. 粤西白垩纪火山-侵入岩浆活动及其地质意义[J]. 中国科学: 地球科学, 2006, 36(7):601-617.
[8]	潘登, 吴仁贵, 邓伟强, 等. 水汶盆地碎斑熔岩LA-ICP-MS锆石U-Pb年龄及地球化学特征[J]. 东华理工大学学报(自然科学版), 2013, 36(1):25-34.
[9]	林义华, 吕昭英, 袁勤敏, 等. 琼北儋州市洛基地区早白垩世火山岩的锆石U-Pb年龄、地球化学特征及其地质意义[J]. 华南地质与矿产, 2019, 35(4):399-409.
[10]	周云, 梁新权, 梁细荣, 等. 海南白垩纪六罗村组火山岩的年代学、地球化学特征及其大地构造意义[J]. 大地构造与成矿学, 2015, 39(5):903-918.
[11]	ZHOU Y, LIANG X Q, KRÖNER A, et al. Late Cretaceous lithospheric extension in SE China: Constraints from volcanic rocks in Hainan Island[J]. Lithos, 2015, 232:100-110. DOI URL
[12]	方念乔. “海南陆缘弧”体系的构建与“特提斯南海”的识别: 一个关于“古南海”演化新模式的探讨[J]. 地学前缘, 2016, 23(6):107-119.
[13]	闵慧, 任建业, 高金耀, 等. 南海北部古俯冲带的位置及其对南海扩张的控制[J]. 大地构造与成矿学, 2010, 34(4):599-605.
[14]	张丽鹏. 特提斯闭合与白垩纪成矿: 以阳春盆地为例[D]. 广州: 中国科学院广州地球化学研究所, 2017.
[15]	强萌麟. 南海北部陆缘白垩纪安山岩基本特征及其与东南沿海安山岩对比[D]. 北京: 中国地质大学(北京), 2016.
[16]	韩琦. 南海北部陆缘中、新生代流纹岩基本特征研究[D]. 北京: 中国地质大学(北京), 2017.
[17]	梁飞刚. 琼南晚燕山期花岗岩研究[D]. 北京: 中国地质大学(北京), 2013.
[18]	董海龙. 琼南—越南白垩纪花岗岩岩石地球化学特征与古南海构造演化[D]. 北京: 中国地质大学(北京), 2014.
[19]	袁晓博, 方念乔, 董海龙. 海南岛高峰、保城地区花岗岩年代学、地球化学特征及构造意义[J]. 现代地质, 2019, 33(1):85-97.
[20]	汤稚音. 南海北缘陆相盆地白垩系沉积学与地球化学特征研究[D]. 北京: 中国地质大学(北京), 2014.
[21]	梁霄. 茂名盆地晚中生代沉积记录与古南海演化[D]. 北京: 中国地质大学(北京), 2015.
[22]	贾磊. 三水盆地与茂名盆地白垩系构造沉积特征及其对古南海俯冲的响应[D]. 北京: 中国地质大学(北京), 2016.
[23]	YU J H, O’REILLY Y S, WANG L J, et al. Finding of ancient materials in Cathaysia and implication for the formation of Precambrian crust[J]. Chinese Science Bulletin, 2007, 52(1):13-22. DOI URL
[24]	YU J H, WANG L J, O’REILLY S Y, et al. A Paleoproterozoic orogeny recorded in a long-lived cratonic remnant (Wuyishan terrane), eastern Cathaysia Block, China[J]. Precambrian Research, 2009, 174(3/4):347-363. DOI URL
[25]	YU J H, O’REILLY S Y, WANG L J, et al. Components and episodic growth of Precambrian crust in the Cathaysia Block, South China: Evidence from U-Pb ages and Hf isotopes of zircons in Neoproterozoic sediments[J]. Precambrian Research, 2010, 181(1/2/3/4):97-114. DOI URL
[26]	LIU X, GAO S, DIWU C, et al. Precambrian crustal growth of Yangtze Craton as revealed by detrital zircon studies[J]. American Journal of Science, 2008, 308(4):421-468. DOI URL
[27]	WANG Y J, ZHANG F F, FAN W M, et al. Tectonic setting of the South China Block in the Early Paleozoic: Resolving intracontinental and ocean closure models from detrital zircon U-Pb geochronology[J]. Tectonics, 2010, 29(6): TC6020.
[28]	广西壮族自治区地质矿产局. 广西壮族自治区区域地质志[M]. 北京: 地质出版社, 1985: 351-355.
[29]	广东省地质矿产局. 广东省区域地质志 [M]. 北京: 地质出版社, 1988: 320-322.
[30]	巫建华, 周维勋, 章邦桐. 江西及广东北部中生代晚期地层层序和时代: 兼论《江西省岩石地层》中存在的问题[J]. 地质论评, 2002, 48(1):44-53.
[31]	LIU Y S, GAO S, HU Z C, et al. 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[J]. Journal of Petrology, 2010, 51(1/2):537-571. DOI URL
[32]	侯可军, 李延河, 田有荣. LA-MC-ICP-MS锆石微区原位U-Pb定年技术[J]. 矿床地质, 2009, 28(4):481-492.
[33]	BELOUSOVA E, GRIFFIN W, O’REILLY S Y, et al. Igneous zircon: Trace element composition as an indicator of source rock type[J]. Contributions to Mineralogy and Petrology, 2002, 143(5):602-622. DOI URL
[34]	巫建华, 徐勋胜, 刘帅. 赣南-粤北地区晚白垩世早期长英质火山岩SHRIMP锆石U-Pb年龄及其地质意义[J]. 地质通报, 2012, 31(8):1296-1305.
[35]	劳玉军, 巫建华, 徐勋胜. 粤北长塘盆地晚白垩世早期流纹岩的成因: 地球化学和Sr-Nd-Pb-Hf-O同位素制约[J]. 岩矿测试, 2016, 35(5):558-567.
[36]	TATSUMI Y. High-Mg andesites in the Setouchi volcanic belt, Southwestern Japan: analogy to Archean magmatism and continental crust formation?[J]. Annual Review of Earth and Planetary Sciences, 2006, 34(1):467-499. DOI URL
[37]	CRAWFORD A J, FALLOON T J, GREEN D H. Classification petrogenesis and tectonic setting of boninites[M]//CRAWFORD A J.Boninites [M]. London: Academic Division of Unwin Hyaman, Ltd, 1989: 1-49.
[38]	SAUNDERS A D, ROGERS G, MARRINER G F, et al. Geochemistry of Cenezoic volcanic rocks, Baja California, Mexico: Implications for the petrogenesis of post-subduction magmas[J]. Journal of Volcanology and Geothermal Research, 1987, 32(1/2/3):223-245. DOI URL
[39]	MIDDLEMOST E A K. Naming materials in the magma/igneous rock system[J]. Earth-Science Reviews, 1994, 37(3/4):215-224. DOI URL
[40]	IRVINE T N, BARAGAR W R A. A guide to the chemical classification of the common volcanic rocks[J]. Canadian Journal of Earth Sciences, 1971, 8(5):523-548. DOI URL
[41]	PECCERILLO A, TAYLOR S R. Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, Northern Turkey[J]. Contributions to Mineralogy and Petrology, 1976, 58(1):63-81. DOI URL
[42]	邓晋福, 刘翠, 冯艳芳, 等. 高镁安山岩/闪长岩类(HMA)和镁安山岩/闪长岩类(MA): 与洋俯冲作用相关的两类典型的火成岩类[J]. 中国地质, 2010, 37(4):1112-1118.
[43]	MCCARRON J J, SMELLIE J L. Tectonic implications of fore-arc magmatism and generation of high-magnesian andesites: Alexander Island, Antarctica[J]. Journal of the Geological Society, 1998, 155(2):269-280. DOI URL
[44]	SUN S S, MCDONOUGH W F. Chemical and isotopic systematics of oceanic basalts: Implications for mantle composition and processes[J]. Geological Society, London, Special Publications, 1989, 42(1):313-345. DOI URL
[45]	DEFANT M J, DRUMMOND M S. Derivation of some modern arc magmas by melting of young subducted lithosphere[J]. Nature, 1990, 347:662-665. DOI URL
[46]	SHIMODA G, TATSUMI Y, NOHDA S, et al. Setouchi high-Mg andesites revisited: Geochemical evidence for melting of subducting sediments[J]. Earth and Planetary Science Letters, 1998, 160(3/4):479-492. DOI URL
[47]	TATSUMI Y, EGGINS S. Subduction Zone Magmatism[M]. Oxford: Blackwell, 1995: 211.
[48]	KELEMEN P B, HANGHØJ K, GREENE A R. One view of the geochemistry of subduction-related magmatic arcs, with an emphasis on primitive andesite and lower crust[M]// Treatise on Geochemistry. Amsterdam: Elsevier, 2007: 1-70.
[49]	MCCULLOCH M T, GAMBLE J A. Geochemical and geodynamical constraints on subduction zone magmatism[J]. Earth and Planetary Science Letters, 1991, 102(3/4):358-374. DOI URL
[50]	LA FLÈCHE M R, CAMIRÉ G, JENNER G A. Geochemistry of post-Acadian, Carboniferous continental intraplate basalts from the Maritimes Basin, Magdalen Islands, Québec, Canada[J]. Chemical Geology, 1998, 148(3/4):115-136. DOI URL
[51]	TURNER S, CAULFIELD J, TURNER M, et al. Recent contribution of sediments and fluids to the mantle’s volatile budget[J]. Nature Geoscience, 2012, 5(1):50-54. DOI URL
[52]	KOHUT E J, STERN R J, KENT A J R, et al. Evidence for adiabatic decompression melting in the Southern Mariana Arc from high-Mg lavas and melt inclusions[J]. Contributions to Mineralogy and Petrology, 2006, 152(2):201-221. DOI URL
[53]	PEARCE J A, PEATE D W. Tectonic implications of the composition of volcanic ARC Magmas[J]. Annual Review of Earth and Planetary Sciences, 1995, 23(1):251-285. DOI URL
[54]	HOFMANN A W. Chemical differentiation of the Earth: the relationship between mantle, continental crust, and oceanic crust[J]. Earth and Planetary Science Letters, 1988, 90(3):297-314. DOI URL
[55]	KAMEI A, OWADA M, NAGAO T, et al. High-Mg diorites derived from sanukitic HMA magmas, Kyushu Island, southwest Japan arc: evidence from clinopyroxene and whole rock compositions[J]. Lithos, 2004, 75(3/4):359-371. DOI URL
[56]	CONDIE K C. Geochemistry and tectonic setting of early Proterozoic supracrustal rocks in the southwestern United States[J]. The Journal of Geology, 1986, 94(6):845-864. DOI URL
[57]	BAILEY J C. Geochemical criteria for a refined tectonic discrimination of orogenic andesites[J]. Chemical Geology, 1981, 32(1/2/3/4):139-154. DOI URL
[58]	ZHOU X M, LI W X. Origin of Late Mesozoic igneous rocks in Southeastern China: Implications for lithosphere subduction and underplating of mafic magmas[J]. Tectonophysics, 2000, 326(3/4):269-287. DOI URL
[59]	ZHOU X M, SUN T, SHEN W Z, et al. Petrogenesis of Mesozoic granitoids and volcanic rocks in South China: A response to tectonic evolution[J]. Episodes, 2006, 29(1):26-33. DOI URL
[60]	WONG J, SUN M, XING G F, et al. Geochemical and zircon U-Pb and Hf isotopic study of the Baijuhuajian metaluminous A-type granite: Extension at 125-100 Ma and its tectonic significance for South China[J]. Lithos, 2009, 112(3/4):289-305. DOI URL
[61]	张倩, 吴湘滨, 杨牧, 等. 福建紫金山矿集区浸铜湖花岗斑岩的成因及构造意义[J]. 现代地质, 2019, 33(5):1025-1035.
[62]	陈卫锋, 陈培荣, 徐夕生, 等. 华南白垩纪玄武质岩石的地球化学特征及其对太平洋板块俯冲作用的制约[J]. 中国科学:地球科学, 2005, 35(11):1007-1018.
[63]	SHINJO R. Geochemistry of high Mg andesites and the tectonic evolution of the Okinawa Trough-Ryukyu arc system[J]. Chemical Geology, 1999, 157(1/2):69-88. DOI URL
[64]	TSUCHIYA N, SUZUKI S, KIMURA J I, et al. Evidence for slab melt/mantle reaction: Petrogenesis of Early Cretaceous and Eocene high-Mg andesites from the Kitakami Mountains, Japan[J]. Lithos, 2005, 79(1/2):179-206. DOI URL
[65]	SATO M, SHUTO K, NOHARA-IMANAKA R, et al. Repeated magmatism at 34 Ma and 23-20 Ma producing high magnesian adakitic andesites and transitional basalts on southern Okushiri Island, NE Japan arc[J]. Lithos, 2014, 205:60-83. DOI URL
[66]	PLANK T, LANGMUIR C H. The chemical composition of subducting sediment and its consequences for the crust and mantle[J]. Chemical Geology, 1998, 145(3/4):325-394. DOI URL
[67]	PATCHETT P J, WHITE W M, FELDMANN H, et al. Hafnium/rare earth element fractionation in the sedimentary system and crustal recycling into the Earth’s mantle[J]. Earth and Planetary Science Letters, 1984, 69(2):365-378. DOI URL
[68]	夏戡原, 黄慈流. 南海中生代特提斯期沉积盆地的发现与找寻中生代含油气盆地的前景[J]. 地学前缘, 2000, 7(3):227-238.
[69]	颜佳新, 周蒂. 南海北部陆缘区中特提斯构造演化研究[J]. 海洋地质与第四纪地质, 2001, 21(4):49-54.
[70]	邵磊, 尤洪庆, 郝沪军, 等. 南海东北部中生界岩石学特征及沉积环境[J]. 地质论评, 2007, 53(2):164-169.
[71]	肖昌浩, 申玉科, 韦昌山, 等. 广西右江褶皱带东南缘西大明山矿集区燕山期酸性岩浆锆石U-Pb年龄、Hf同位素和Ce(Ⅳ)/Ce(Ⅲ)特征[J]. 现代地质, 2018, 32(2):289-304.
[72]	朱伟林, 解习农, 王振峰, 等. 南海西沙隆起基底成因新认识[J]. 中国科学: 地球科学, 2017, 47(12):1460-1468.
[73]	ZHANG L P, HU Y B, LIANG J L, et al. Adakitic rocks associated with the Shilu copper-molybdenum deposit in the Yangchun Basin, South China, and their tectonic implications[J]. Acta Geochimica, 2017, 36(2):132-150. DOI URL
[74]	SUN S J, ZHANG L P, ZHANG R Q, et al. Mid-Late Cretaceous igneous activity in South China: The Qianjia example, Hainan island[J]. International Geology Review, 2018, 60(11/12/13/14):1665-1683. DOI URL
[75]	唐功建, 王强. 高镁安山岩及其地球动力学意义[J]. 岩石学报, 2010, 26(8):2495-2512.
[76]	KELEMEN P B. Genesis of high Mg^# andesites and the continental crust[J]. Contributions to Mineralogy and Petrology, 1995, 120(1):1-19. DOI URL
[77]	TATSUMI Y, HANYU T. Geochemical modeling of dehydration and partial melting of subducting lithosphere: Toward a comprehensive understanding of high-Mg andesite formation in the Setouchi volcanic belt, SW Japan[J]. Geochemistry, Geophysics, Geosystems, 2003, 4(9):1081.
[78]	ROGERS G, SAUNDERS A D, TERRELL D J, et al. Geochemistry of Holocene volcanic rocks associated with ridge subduction in Baja California, Mexico[J]. Nature, 1985, 315:389-392. DOI URL
[79]	GUIVEL C, LAGABRIELLE Y, BOURGOIS J, et al. New geochemical constraints for the origin of ridge-subduction-related plutonic and volcanic suites from the Chile Triple Junction (Taitao Peninsula and Site 862, LEG ODP141 on the Taitao Ridge)[J]. Tectonophysics, 1999, 311(1/2/3/4):83-111. DOI URL
[80]	MICHAUD F, ROYER J Y, BOURGOIS J, et al. Oceanic-ridge subduction vs. slab break off: Plate tectonic evolution along the Baja California Sur continental margin since 15 Ma[J]. Geology, 2006, 34(1):13. DOI URL
[81]	WANG Q, LI X H, JIA X H, et al. Late Early Cretaceous adakitic granitoids and associated magnesian and potassium-rich mafic enclaves and dikes in the Tunchang-Fengmu area, Hainan Province (South China): Partial melting of lower crust and mantle, and magma hybridization[J]. Chemical Geology, 2012, 328:222-243. DOI URL
[82]	张泽明, 丁慧霞, 董昕, 等. 冈底斯岩浆弧的形成与演化[J]. 岩石学报, 2019, 35(2):275-294.
[83]	JIANG Z Q, WANG Q, LI Z X, et al. Late Cretaceous (ca. 90 Ma) adakitic intrusive rocks in the Kelu area, Gangdese Belt (southern Tibet): Slab melting and implications for Cu-Au mineralization[J]. Journal of Asian Earth Sciences, 2012, 53:67-81. DOI URL
[84]	徐倩, 曾令森, 高家昊, 等. 西藏南部冈底斯南缘松卡晚白垩世埃达克质高镁闪长岩地球化学特征及其成因[J]. 岩石学报, 2019, 35(2):455-471.
[85]	ZHANG L L, ZHU D C, WANG Q, et al. Late Cretaceous volcanic rocks in the Sangri area, southern Lhasa Terrane, Tibet: Evidence for oceanic ridge subduction[J]. Lithos, 2019, 326/327:144-157. DOI URL

点号	Th/ 10^-6	U/ 10^-6	Th/ U	同位素比值				年龄/Ma
点号	Th/ 10^-6	U/ 10^-6	Th/ U	²⁰⁷Pb/²⁰⁶Pb±1σ	²⁰⁷Pb/²³⁵U±1σ	²⁰⁶Pb/²³⁸U±1σ		²⁰⁷Pb/²⁰⁶Pb±1σ		²⁰⁷Pb/²³⁵U±1σ		²⁰⁶Pb/²³⁸U±1σ
4	778	660	1.18	0.052 943±0.002 028	0.105 863±0.004 260	0.014 550±0.000 162	327.84±87.03		102.17±3.91		93.12±1.03
8	215	319	0.67	0.055 402±0.005 689	0.106 484±0.009 310	0.014 642±0.000 365	427.83±226.82		102.74±8.54		93.71±2.32
10	785	647	1.21	0.048 431±0.002 114	0.095 819±0.004 078	0.014 437±0.000 160	120.46±103.69		92.91±3.78		92.40±1.02
12	662	887	0.75	0.052 819±0.002 251	0.105 023±0.004 352	0.014 548±0.000 155	320.43±98.14		101.40±4.00		93.11±0.98
13	52	563	0.09	0.047 487±0.004 553	0.095 395±0.009 201	0.014 721±0.000 308	72.32±214.79		92.52±8.53		94.21±1.95
17	807	1 007	0.80	0.048 714±0.001 889	0.097 236±0.003 751	0.014 577±0.000 148	200.08±97.21		94.22±3.47		93.29±0.94
18	288	1 658	0.17	0.048 054±0.001 621	0.097 694±0.003 339	0.014 783±0.000 153	101.94±84.25		94.65±3.09		94.60±0.97
1	370	1 097	0.34	0.069 394±0.000 946	1.479 264±0.022 043	0.154 699±0.001 383	910.19±27.78		921.93±9.03		927.25±7.72
2	352	814	0.43	0.073 216±0.001 017	1.542 407±0.023 326	0.152 604±0.001 137	1 020.37±28.55		947.47±9.32		915.54±6.36
3	6	722	0.01	0.151 631±0.001 552	8.842 395±0.097 376	0.422 511±0.002 668	2 364.51±18.36		2 321.88±10.05		2 271.87±12.09
5	360	1 971	0.18	0.060 137±0.000 686	0.842 628±0.010 756	0.101 390±0.000 711	609.28±24.07		620.59±5.93		622.55±4.16
6	375	1 076	0.35	0.089 175±0.000 967	2.883 195±0.032 698	0.234 226±0.001 542	1 409.26±20.83		1 377.53±8.55		1 356.61±8.05
7	214	722	0.30	0.070 226±0.001 039	1.500 139±0.025 399	0.154 576±0.001 463	1 000.00±29.63		930.44±10.32		926.56±8.17
9	570	871	0.65	0.072 671±0.001 129	1.533 127±0.027 094	0.152 402±0.001 352	1 005.56±31.48		943.75±10.86		914.41±7.57
11	614	896	0.69	0.097 284±0.001 131	3.598 950±0.046 454	0.267 513±0.002 156	1 572.53±21.76		1 549.30±10.26		1 528.17±10.96
14	2 119	662	3.20	0.064 143±0.001 041	0.993 233±0.015 529	0.112 186±0.000 638	746.30±33.33		700.37±7.91		685.43±3.70
15	536	507	1.06	0.059 697±0.001 110	0.838 994±0.016 053	0.101 737±0.000 750	592.31±40.73		618.59±8.86		624.58±4.39
16	432	551	0.78	0.064 711±0.001 099	1.103 915±0.019 405	0.123 530±0.000 941	764.82±236.11		755.24±9.37		750.85±5.40

点号	Th/ 10^-6	U/ 10^-6	Th/ U	同位素比值				年龄/Ma
点号	Th/ 10^-6	U/ 10^-6	Th/ U	²⁰⁷Pb/²⁰⁶Pb±1σ	²⁰⁷Pb/²³⁵U±1σ	²⁰⁶Pb/²³⁸U±1σ		²⁰⁷Pb/²⁰⁶Pb±1σ		²⁰⁷Pb/²³⁵U±1σ		²⁰⁶Pb/²³⁸U±1σ
4	778	660	1.18	0.052 943±0.002 028	0.105 863±0.004 260	0.014 550±0.000 162	327.84±87.03		102.17±3.91		93.12±1.03
8	215	319	0.67	0.055 402±0.005 689	0.106 484±0.009 310	0.014 642±0.000 365	427.83±226.82		102.74±8.54		93.71±2.32
10	785	647	1.21	0.048 431±0.002 114	0.095 819±0.004 078	0.014 437±0.000 160	120.46±103.69		92.91±3.78		92.40±1.02
12	662	887	0.75	0.052 819±0.002 251	0.105 023±0.004 352	0.014 548±0.000 155	320.43±98.14		101.40±4.00		93.11±0.98
13	52	563	0.09	0.047 487±0.004 553	0.095 395±0.009 201	0.014 721±0.000 308	72.32±214.79		92.52±8.53		94.21±1.95
17	807	1 007	0.80	0.048 714±0.001 889	0.097 236±0.003 751	0.014 577±0.000 148	200.08±97.21		94.22±3.47		93.29±0.94
18	288	1 658	0.17	0.048 054±0.001 621	0.097 694±0.003 339	0.014 783±0.000 153	101.94±84.25		94.65±3.09		94.60±0.97
1	370	1 097	0.34	0.069 394±0.000 946	1.479 264±0.022 043	0.154 699±0.001 383	910.19±27.78		921.93±9.03		927.25±7.72
2	352	814	0.43	0.073 216±0.001 017	1.542 407±0.023 326	0.152 604±0.001 137	1 020.37±28.55		947.47±9.32		915.54±6.36
3	6	722	0.01	0.151 631±0.001 552	8.842 395±0.097 376	0.422 511±0.002 668	2 364.51±18.36		2 321.88±10.05		2 271.87±12.09
5	360	1 971	0.18	0.060 137±0.000 686	0.842 628±0.010 756	0.101 390±0.000 711	609.28±24.07		620.59±5.93		622.55±4.16
6	375	1 076	0.35	0.089 175±0.000 967	2.883 195±0.032 698	0.234 226±0.001 542	1 409.26±20.83		1 377.53±8.55		1 356.61±8.05
7	214	722	0.30	0.070 226±0.001 039	1.500 139±0.025 399	0.154 576±0.001 463	1 000.00±29.63		930.44±10.32		926.56±8.17
9	570	871	0.65	0.072 671±0.001 129	1.533 127±0.027 094	0.152 402±0.001 352	1 005.56±31.48		943.75±10.86		914.41±7.57
11	614	896	0.69	0.097 284±0.001 131	3.598 950±0.046 454	0.267 513±0.002 156	1 572.53±21.76		1 549.30±10.26		1 528.17±10.96
14	2 119	662	3.20	0.064 143±0.001 041	0.993 233±0.015 529	0.112 186±0.000 638	746.30±33.33		700.37±7.91		685.43±3.70
15	536	507	1.06	0.059 697±0.001 110	0.838 994±0.016 053	0.101 737±0.000 750	592.31±40.73		618.59±8.86		624.58±4.39
16	432	551	0.78	0.064 711±0.001 099	1.103 915±0.019 405	0.123 530±0.000 941	764.82±236.11		755.24±9.37		750.85±5.40

样品	编号	SiO₂			TiO₂			Al₂O₃			FeO^T			MnO			MgO			CaO				Na₂O			K₂O			P₂O₅			烧失量			总量
玉林	LC1-1	54.67			0.81			15.72			7.09			0.13			7.61			7.83				2.8			2.06			0.17			1.24			100.13
	LC4-1	54.07			0.80			15.16			7.67			0.12			8.28			7.54				2.88			2.02			0.17			1.47			100.17
	LC2-1	54.39			0.80			15.48			7.67			0.13			7.84			7.35				2.83			2.05			0.17			1.37			100.07
	LC2-2	54.31			0.80			15.46			7.74			0.12			7.85			7.32				2.88			2.09			0.17			1.33			100.07
连平	LP4-1	60.55			0.73			16.86			5.65			0.11			3.05			5.93				3.20			2.19			0.40			0.99			99.66
	LP4-1b	60.28			0.71			17.00			5.59			0.11			3.23			5.92				3.30			2.17			0.39			0.96			99.66
	LP4-2	60.52			0.65			17.17			5.47			0.13			3.14			5.96				3.10			2.11			0.40			0.96			99.61
样品	编号	La	Ce			Pr			Nd			Sm			Eu			Gd			Tb		Dy			Ho			Er			Tm			Yb		Lu
玉林	LC1-1	28.7	51.8			6.44			24.5			4.41			1.11			3.51			0.62		3.19			0.63			1.73			0.31			1.80		0.45
	LC4-1	24.3	40.6			5.25			19.5			3.51			0.87			2.89			0.49		2.50			0.50			1.35			0.25			1.52		0.40
	LC2-1	27.0	49.9			6.13			24.0			4.38			1.23			3.77			0.58		3.25			0.62			1.76			0.28			1.81		0.26
	LC2-2	26.7	50.7			6.12			23.4			4.39			1.25			3.82			0.60		3.27			0.62			1.77			0.27			1.82		0.27
连平	LP4-1	35.4	65.4			7.65			29.0			5.07			1.65			4.36			0.62		3.26			0.63			1.83			0.28			1.77		0.28
	LP4-1b	35.6	65.5			7.62			28.8			5.05			1.62			4.33			0.61		3.24			0.62			1.81			0.27			1.76		0.29
	LP4-2	36.8	67.6			7.91			29.7			5.26			1.72			4.50			0.64		3.40			0.65			1.87			0.29			1.84		0.29
样品	编号	Y		Ba			Rb			Th			Nb			U			Ta			Sr			Zr			Hf			Pb			Sc			V
玉林	LC1-1	16.5		570			61.3			8.00			8.97			1.81			0.90			530			164			4.51			12.7			22.2			174
	LC4-1	13.1		589			65.0			7.89			8.73			1.73			0.50			533			125			3.35			12.4			23.2			163
	LC2-1	17.2		549			66.2			7.51			8.04			1.59			0.51			509			167			4.40			13.0			25.4			146
	LC2-2	17.5		556			65.1			7.36			8.27			1.48			0.51			515			164			4.30			11.0			20.3			142
连平	LP4-1	17.8		766			71.9			6.43			17.4			1.31			1.21			810			126			3.46			21.6			11.9			100
	LP4-1b	17.8		757			71.8			6.44			17.5			1.33			1.15			810			128			3.49			20.8			11.7			098
	LP4-2	18.5		910			70.7			6.70			17.7			1.37			1.17			818			130			3.56			21.5			12.5			105
样品	编号	Cr			Co			Ni			(La/Yb)_N			Eu/Eu^*			Sr/Y			La/Yb				Nb/Yb			Th/Yb			Zr/Yb			Th/Nb			U/Th
玉林	LC1-1	369			33.1			147			11.42			0.84			32.09			15.92				4.98			4.44			91.34			0.89			0.23
	LC4-1	353			34.3			148			11.47			0.81			40.82			15.99				5.75			5.19			82.04			0.90			0.22
	LC2-1	424			34.6			134			10.70			0.90			29.53			14.91				4.43			4.14			92.35			0.93			0.21
	LC2-2	415			33.8			128			10.54			0.91			29.34			14.70				4.55			4.04			90.27			0.89			0.20
连平	LP4-1	32.8			16.4			18.2			14.35			1.05			45.51			20.00				9.83			3.63			71.19			0.37			0.20
	LP4-1b	34.3			15.7			17.7			14.51			1.03			45.51			20.23				9.94			3.66			72.73			0.37			0.21
	LP4-2	36.1			20.5			19.1			14.35			1.05			44.22			20.00				9.62			3.64			70.65			0.38			0.20

样品	编号	SiO₂			TiO₂			Al₂O₃			FeO^T			MnO			MgO			CaO				Na₂O			K₂O			P₂O₅			烧失量			总量
玉林	LC1-1	54.67			0.81			15.72			7.09			0.13			7.61			7.83				2.8			2.06			0.17			1.24			100.13
	LC4-1	54.07			0.80			15.16			7.67			0.12			8.28			7.54				2.88			2.02			0.17			1.47			100.17
	LC2-1	54.39			0.80			15.48			7.67			0.13			7.84			7.35				2.83			2.05			0.17			1.37			100.07
	LC2-2	54.31			0.80			15.46			7.74			0.12			7.85			7.32				2.88			2.09			0.17			1.33			100.07
连平	LP4-1	60.55			0.73			16.86			5.65			0.11			3.05			5.93				3.20			2.19			0.40			0.99			99.66
	LP4-1b	60.28			0.71			17.00			5.59			0.11			3.23			5.92				3.30			2.17			0.39			0.96			99.66
	LP4-2	60.52			0.65			17.17			5.47			0.13			3.14			5.96				3.10			2.11			0.40			0.96			99.61
样品	编号	La	Ce			Pr			Nd			Sm			Eu			Gd			Tb		Dy			Ho			Er			Tm			Yb		Lu
玉林	LC1-1	28.7	51.8			6.44			24.5			4.41			1.11			3.51			0.62		3.19			0.63			1.73			0.31			1.80		0.45
	LC4-1	24.3	40.6			5.25			19.5			3.51			0.87			2.89			0.49		2.50			0.50			1.35			0.25			1.52		0.40
	LC2-1	27.0	49.9			6.13			24.0			4.38			1.23			3.77			0.58		3.25			0.62			1.76			0.28			1.81		0.26
	LC2-2	26.7	50.7			6.12			23.4			4.39			1.25			3.82			0.60		3.27			0.62			1.77			0.27			1.82		0.27
连平	LP4-1	35.4	65.4			7.65			29.0			5.07			1.65			4.36			0.62		3.26			0.63			1.83			0.28			1.77		0.28
	LP4-1b	35.6	65.5			7.62			28.8			5.05			1.62			4.33			0.61		3.24			0.62			1.81			0.27			1.76		0.29
	LP4-2	36.8	67.6			7.91			29.7			5.26			1.72			4.50			0.64		3.40			0.65			1.87			0.29			1.84		0.29
样品	编号	Y		Ba			Rb			Th			Nb			U			Ta			Sr			Zr			Hf			Pb			Sc			V
玉林	LC1-1	16.5		570			61.3			8.00			8.97			1.81			0.90			530			164			4.51			12.7			22.2			174
	LC4-1	13.1		589			65.0			7.89			8.73			1.73			0.50			533			125			3.35			12.4			23.2			163
	LC2-1	17.2		549			66.2			7.51			8.04			1.59			0.51			509			167			4.40			13.0			25.4			146
	LC2-2	17.5		556			65.1			7.36			8.27			1.48			0.51			515			164			4.30			11.0			20.3			142
连平	LP4-1	17.8		766			71.9			6.43			17.4			1.31			1.21			810			126			3.46			21.6			11.9			100
	LP4-1b	17.8		757			71.8			6.44			17.5			1.33			1.15			810			128			3.49			20.8			11.7			098
	LP4-2	18.5		910			70.7			6.70			17.7			1.37			1.17			818			130			3.56			21.5			12.5			105
样品	编号	Cr			Co			Ni			(La/Yb)_N			Eu/Eu^*			Sr/Y			La/Yb				Nb/Yb			Th/Yb			Zr/Yb			Th/Nb			U/Th
玉林	LC1-1	369			33.1			147			11.42			0.84			32.09			15.92				4.98			4.44			91.34			0.89			0.23
	LC4-1	353			34.3			148			11.47			0.81			40.82			15.99				5.75			5.19			82.04			0.90			0.22
	LC2-1	424			34.6			134			10.70			0.90			29.53			14.91				4.43			4.14			92.35			0.93			0.21
	LC2-2	415			33.8			128			10.54			0.91			29.34			14.70				4.55			4.04			90.27			0.89			0.20
连平	LP4-1	32.8			16.4			18.2			14.35			1.05			45.51			20.00				9.83			3.63			71.19			0.37			0.20
	LP4-1b	34.3			15.7			17.7			14.51			1.03			45.51			20.23				9.94			3.66			72.73			0.37			0.21
	LP4-2	36.1			20.5			19.1			14.35			1.05			44.22			20.00				9.62			3.64			70.65			0.38			0.20