39 6 : 1701 [6] 1 ( ) Fig.1 Geological sketch map of Hainai Island (modified after Reference [6] ) 1-b) [2] - ( 1- ( 1-b) b) [7-10] - - [ ] - [1

Size: px

Start display at page:

Download "39 6 : 1701 [6] 1 ( ) Fig.1 Geological sketch map of Hainai Island (modified after Reference [6] ) 1-b) [2] - ( 1- ( 1-b) b) [7-10] - - [2817-18] - [1"

犹十郑
7 years ago
Views:

1 GEOLOGY IN CHINA Vol.39No.6 Dec (1. 中国地质科学院矿产资源研究所国土资源部成矿作用与资源评价重点实验室北京 ; 2. 海南矿业联合有限公司海南昌江 ; 3. 中国地质大学北京 ) : - REE ~ ; LREE/HREE 4.44~9.67(La/Yb) N 3.95~10.69; Eu (δeu=0.28~ 0.57)Ba Nb(-Ta) Ce Sr P Ti Ba Sr Eu 87 Sr/ 86 Sr (I Sr ) ~ (1 I Sr ) ε Nd (t)= 7.3~-9.1T DM2 1.5~1.9 Ga I Sr ε Nd (t) T DM2 : ; ; ; :P618.31;P :A : (2012) U-Pb 230 Ma( ) ( 1) Rb-Sr U-Pb 320~272 Ma [1-3] S Nd Sr [13] I-S ( - ) SHRIMP U-Pb 237 Ma [4] U-Pb 226~234 Ma [5] SHRIMP U-Pb (186±3) Ma [4] 1 ( 1-a) LA-ICP-MS ( : ; : : ( ) : 1966 ; yjjchina@sina.com

715 492(1 I Sr 0.706 364) ε Nd (t)= 7.3~-9.1T DM2 1.5~1.9 Ga I Sr ε Nd (t) T DM2 : ; ; ; :P618.31;P588.

2 39 6 : 1701 [6] 1 ( ) Fig.1 Geological sketch map of Hainai Island (modified after Reference [6] ) 1-b) [2] - ( 1- ( 1-b) b) [7-10] - - [ ] - [11-14] - 37% - ( ) - [1516] ( SHRIMP U-Pb 262~267 Ma [19] ) ( U-Pb 226~237 Ma [45] ) ( SHRIMP U-Pb (249±5) Ma [20] )

[6] ) 1-b) [2] - ( 1- ( 1-b) b) [7-10] - - [2817-18] - [11-14] -

3 [5] X ( 2) PW2404 X (40% ) (30%~35%) (ICP-MS) (15%~20%) (5%~10%) Finnigan MAT HR-ICP-MS(Element : ) (RSD)<5% 2~4 mm Sr Nd (An 20-30) ISOPROBE-T Rb-Sr Sm-Nd 0.2 mm (An 2σ 30-35) 3-5~7 mm <5 mm <2 mm [21] 2 ( ) Fig.2 Geological sketch map of the Shilu deposit and its surrounding area (modified after Reference [21] )

4 39 6 : % 10-6 Table 1 Major elements % trace elements and rare earth elements 10-6 data of granites in the periphery of the Shilu iron deposit ( 1) : SiO % ~74.26% Na 2 O +K 2 O 6.39% ~9.15% K 2 O/Na 2 O 1.07~2.48 TAS Nb ~ Ta ( ) / ~ SiO 2 -K 2 O Rb ~ ( 3) Ba ~ U Al 2 O 3 TiO 2 P 2 O 5 MgO CaO ~ Th ~ (A/CNK) 0.91~1.25A / NK 1.15~1.50 ( 4) ~5.73 ( 5)Rb A/CNK>1.1 Th-(K) Pb Ba Nb(-Ta) Ce Sr P Ti FeO * /MgO 3.68~4.38 S [24] (2.39) 3.2 (HFSE) Zr ~ Hf ~ Nb Ta Sr ~ Rb/Sr REE ~ ; LREE/HREE 4.44~9.67 (La/Yb) N 3.95~10.69;δEu 0.28~0.63 ( 1) : Eu ; (

82 10-6 SiO 2 -K 2 O Rb 144 10-6 ~ ( 3) 324 10-6 Ba 255 10-6 ~627 10-6 U Al 2 O 3 TiO 2 P 2 O 5 MgO CaO 3.49 10-6 ~15.1 10-6 Th 12.6 10-6 ~49.9 10-6 (A/CNK) 0.91~1.25A / NK 1.15~1.

5 SiO 2 -K 2 O ( [22] ) Fig.3 SiO 2 -K 2 O diagram (after Reference [22] ) 4 [23] ( ) Fig.4 A/NK-A/CNK plot of granite (after Reference [23] ) 6) REE 3.3 Sr-Nd 87 Sr-Nd 2 Sr/ 86 Sr (I Sr ) ~ ISr I Sr ~ ε Nd (t)= 7.3~-9.1T DM2 1.5~1.9 Ga I Sr ε Nd (t) T DM Nb/Ta ( 6.52~10.84) ( 11) [26] [2627] (17.5 ±2) [28] Gremiakha Vyrmes ( 22) Rb/Nb 11.42~26.67 (5.36) A [24] S Nb (Nb/La 5 [25] 0.26~0.53) ( ) Fig.5 Primitive-mantle normalized spidergram of granite - in the periphery of the Shilu iron deposit (normalization Ba Sr Nb Ti Rb Th K La values after Reference [25] ) [29] ( 5) Lachlan [3031] [32] [32] Dalat ( H 2 O ) [33]

52~10.84) ( 11) [26] [2627] (17.5 ±2) [28] Gremiakha Vyrmes ( 22) Rb/Nb 11.42~26.67 (5.36) A [24] S Nb (Nb/La 5 [25] 0.26~0.53) ( ) Fig.

6 39 6 : Rb-Sr Sm-Nd Table 2 Rb-Sr and Sm-Nd isotopic compositions of granites in the periphery of the Shilu iron deposit [25] 6 ( ) Fig.6 Chondrite-normalized REE patterns of granite in the periphery of the Shilu iron deposit (normalization values after Reference [25] ) 7) Al 2 O 3 /(FeO * +MgO +TiO 2 ) (Na 2 O +K 2 O)/ (FeO * +MgO+TiO 2 ) ( /

6 Chondrite-normalized REE patterns of granite in the periphery of the Shilu iron

7 [33] Fig.7 Comparison of chemical compositions between the granites in the periphery of the Shilu iron deposit and compositional fields of some experimental melts [33] Sr Ba Eu [3435] 87 Sr/ 86 Sr (I Sr ) ~ I Sr ~ ε Nd (t)=-7.3~-9.1 I Sr T DM2 1.5~1.9 Ga (La/Yb) N 3.95~10.69 ( 6) Sr Ti P I I 4.2 [36] Schwarzwald - [35] K Rb U Th Nb Dalat Cana Deoca Ti ( 5) [32] [323738]

compositional fields of some experimental melts [33] Sr Ba Eu [3435] 87 Sr/ 86 Sr (I Sr ) 0.706 364~ 0.

8 39 6 : 1707 ( 8) 海南岛与俯冲有关的弧岩浆活动 Li et al [19] SHRIMP U-Pb 262~267 Ma ( ) SHRIMP U-Pb 269~278 Ma SHRIMP U-Pb (272±7) Ma [40] Li et al [19] - SiO %~74.5% K 2 O 2.3%~6.9% Na 2 O 2.4%~3.2% K 2 O+Na 2 O 6.3% ~ 9.4%A/CNK 0.9~1.08 (La/Yb) N 5~125 - Eu δeu 0.66~0.18 Ba Sr Nb Ti P Rb Th K I Sr = ε Nd (t) =-3.07 ~-7.72T DM ~1 660 Ma I [18] [39] 8 ( ) Fig.8 Trace elements tectonic discrimination plot for granites (after Reference [39] ) 与同碰撞有关的岩浆活动 240~250 Ma 40 Ar- 39 Ar ~ Ma [41] SHRIMP U-Pb (249±5)Ma [20] Rb Cs Th U Pb Zr Hf - Y Ba Sr P Ti Nb Ta (La/Yb) N =8.29 ~ Rb-Sr (241± 30.36; - EuδEu=0.43~0.05; 7)Ma2 SHRIMP (243±4) I Sr = Ma (241±1) Ma [42] ~ ε Nd (t) =-7.59~-8.46 T DM2 1639~1 709 Ma S A (SiO (HHP) % ~76.31%) (K 2 O 4.46% ~ 6.21%) Na 2 O+ K 2 O 7.53% ~ 9.40%;A/CNK 770~790 (10~12.5)

8 Trace elements tectonic discrimination plot for granites (after Reference [39] ) 4.3.2 与同碰撞有关的岩浆活动 240~250 Ma 40 Ar- 39 Ar 236 0. 92~1.

9 Pa( 34~42 km) [20] 与后碰撞有关的岩浆活动 [43-44] I Sr =0.7058~0.7101ε Nd (t) SHRIMP U-Pb 237 Ma [4] =-4.7~-9.7T DM 1 030~1 500 Ma U-Pb 226~234 Ma [5] LA- ICP-MS U-Pb 230 Ma( ) NE ( SiO 2 =62.9%~67.68 % NE ) ( SiO 2 =71.35%~74.66% SiO 2 =75.22%~ ) ; 76.07% Al 2 O %~17.32 %A/CNK 1.01~ Ba Na U Pb Rb Sr Ar Ar 248~ 245 MaPu Si Lung Rb Sr 259 Ma 5 Truong Son [4344] Rb/Sr ;ε Nd (0) =-13.3~ ~250 Ma [45] - :1) ~272 Ma;2) - SiO 2 = 68.77% ~ 245~259 Ma;3) 75.73%K 2 O+Na 2 O=6.87%~8.42% Ma [43] Nb Ta Sr Ba Dien Bien Beng Giang-Que Son U Th K Rb - Sr Nd - I A/CNK 1.06~ 1.12 Dien Bien U-Pb 272 Ma - Rb-Sr 266~252 Ma Beng Giang -Que Son (1) SHRIMP U-Pb 260 Ma - - (La/Yb) N 8~9 Eu (La/Yb) N 5~ 19 Eu Nb Ta Sr Ba Nb Ta Sr Ba U Th Pb 87 Sr/ 86 Sr ~ T DM 1 800~2 230 Ma 6 (2) Song Ma

56 - Ba Na U Pb Rb Sr Ar Ar 248~ 245 MaPu Si Lung Rb Sr 259 Ma 5 Truong Son [4344] Rb/Sr ;ε Nd (0) =-13.3~-10.2 240~250 Ma [45] - :1) - - 248~272 Ma;2) - SiO 2 = 68.77% ~ 245~259 Ma;3) 75.

10 39 6 : : [7]. Sm-Nd [J] (3): Li Xianhua Zhou Hanwen Ding Shijiang et al. Sm-Nd isotopic constraints on the age of the Bangxi-Chenxing ophiolite in Hainan Island:implications for the tectonic evolution of eastern Paleo - Tethys[J].Acta Petrologica Sinica (3): (in Chinese with English abstract). (3) [8] Li X H Zhou H W Chung S L et al. Geochemical and Sm-Nd isotopic characteristics of metabasites from central Hainan Island South China and their tectonic significance [J]. The Island Arc : (References): [9] Xu D R Xia B Li P C et al. Protolith natures and U-Pb sensitive high mass-resolution ion microprobe (SHRIMP) zircon ages of the [1]. [J] : metabasites in Hainan Island South China:Implications for Xia Bangdong Yu Jinhai Fang Zhong et al. Geochemical geodynamic evolution since the late Precambrian [J]. The Island characteristics and origin of the Hercynian Indosinian granites of Arc : Hainan Island China [J]. Geochemistry 1990 (4): (in [10] Xu D Xia B Nonna B C et al. Geochemistry and Sr-Nd isotope Chinese with English abstract). systematics of metabasites in the Tunchang area Hainan Island [2].. ( ) [M]. 1991: South China:implications for petrogenesis and tectonic setting [J]. Mineralogy and Petrology : Wang Xiaofeng Ma Daquan Jiang Dahai. Geology of Hainan Island (Part 2):Magmatical Rocks [M]. Beijing:Geological [J] (2): Publishing House 1991:1-273(in Chinese). Hou Wei Chen Huifang Liang Xinquan et al. The establishment [3]. of Precambrian strata and new recognition of the geotectonic - Sm-Nd [J] (2): Fang Zhong Yu Jinhai Xia Bangdong et al. Sm -Nd isotopic characteristics of Hercynian -Indosinian granites and xenoliths in evolution in Hainan Island [J]. Journal of Changchun University of Earth sciences (2): (in Chinese with English abstract). [12]. - Sm-Nd Hainan Island south China [J]. Journal of Nanjing University [J] (1): (Natural Sciences Edition) (2): (in Chinese with English abstract). Liang Xinquan. Sm -Nd age and its geological significance for Precambrian granite and greenstone system Hainan Island [J]. Acta [4] Petrologica Sinica (1): (in Chinese with English Sr-Nd [D]. abstract). 2003:1-87. [13]. Ge Xiaoyue. Mesozoic Magmatism in Hainan Island (SE China) and its Tectonic Significance:Geochronology Geochemistry and Sr Nd Isotope Evidences [D]. Ph.D. Thesis of the Graduate School of Ma Daquan Huang Xiangding Xiao Zhifa et al. Crystalline basement of Hainan Island Stratigraphy and age of the Baoban the Chinese Academy of Sciences 2003:1-87. Group [M].Wuhan:Press of China University of Geosciences [5]. U-Pb 1998:1-51. [J] : [14]. Li Sunxiong Yun Ping Fan Yuan et al. Zircon U-Pb age and its geological significance for Qiongzhong pluton in Qiongzhong area Hainan Island [J]. Geotectonica et Metallogenia : (in Chinese with English abstract). [6] Zhang F Wang Y Chen X et al. Triassic high-strain shear zones in Hainan Island (South China) and their implications on the amalgamation of the Indochina and South China Blocks:Kinematic and 40 Ar/ 39 Ar geochronological constraints [J]. Gondwana Research - [11]. [M]. : 1998:1-51. SHRIMP U-Pb [J] (4): Xu Deru Xia Bin Li Pengchunet al. SHRIMP U-Pb dating of zircon from the Precambrian granitoids in northwest Hainan Island and its geological implications [J]. Geotectonica et Metallogenia (4): (in Chinese with English abstract). [15]. [M]. : 2009:1-331.

Acta Petrologica Sinica 2000 16(3):425-432(in Chinese with English abstract). (3) [8] Li X H Zhou H W Chung S L et al.

11 Xu Deru Xiao Yong Xia Bin et al. Model and Ore Prediction of [27] Hofmann A W. Chemical differentiation of the earth:the the Shilu Iron Deposit [M]. Beijing:Geological Publishing House relationship between mantle continental crust and oceanic crust 2009:1-331(in Chinese). [J]. Earth Planetary Science Letters : [16]. Chuaria-Tawuia [28] Bea F Arzamastsev A Montero P et al. Anomalous alkaline rocks [J]. (B ) 1989 (3) of Soustov. Kola: evidence of mantle-derived metasomatic fluids Zhang Renjie Ma Guogan Xu Guanghong et al. Discovery of affecting crustal materials [J]. Contribution to Mineralogy and Chuaria -Tawuia life -form association in Shilu Group Hainan Petrology : Island and its insignificance [J]. Science in China 1989 (3):304- [29] Chappell B W White A J R. I - and S -type granites in the 311(in Chinese). Lachlan Fold Belt. Transactions of the Royal Society of Edinburg [17]. [J]. Earth Sciences :1-26. [M]. : 1986: [30] Harris N B W Pearce J A Tindle A G. Geochemical Research Team of Iron -Rich Ores in South China Chinese characteristics of collision -zone magmatism [C]//Coward M P Academy of Sciences. Geology of the Hainan Island and Ries A C (eds.). Collision Tectonics [M]. Geological Society of Geochemistry of the Shilu Iron Deposit [M].Beijing:Science Press 1986:1-376(in Chinese). London Special Publication : [31] Searle M P Fryer B J. Garnet - tourmaline - and muscovite - [18] Metcalfe I Shergold I H Li Z X. IGCP 321 Gondwana dispersion bearing leucogranites gneisses and migmatites of the higher and Asian accretion:fieldwork on Hainan Ireland [J]. Episodes Himalayas from Zanska Kulu Lahoul and Kashmir [C]//Coward : M P Ries A C (eds.). Collision Tectonics. Geological Society of [19] Li X H Li Z X Li W X et al. Initiation of the Indosinian Orogeny in South China:Evidence for a Permian Magmatic Arc on Hainan Island [J]. Journal of Petrology (3): London Special Publication : [32] Thuy N T B Satir M Siebel W et al. Geochemical and isotopic constraints on the petrogenesis of granitoids from the Dalat zone [20]. southern Vietnam [J]. Journal of Asian Earth Sciences : [J] (10): Xie Caifu Zhu Jinchu Din Shijiang et al. Age and Petrogenesis of [33] Pati 觡 o Douce A E. What do experiments tell us about the relative contributions of crust and mantle to the origin of granitic magmas? the Jianfengling granite and its relationship to metallogenesis of the [C]//Castro A Fernandez C Vigneressese J E (eds.). Baolun gold deposit Hainan Island [J]. Acta Petrologica Sinica Understanding Granites:Intergrating New and Classical (10): (in Chinese with English abstract). Techniques. Geological Society of London Special Publication [21] : (1 5 )[R] Mineral resources and Environment Survey Bureau of Geology and Prospecting of Hainan Province. Map of Level of Work (1/ scale) of the Shilu Iron Deposit and Its Surrounding Region [34] Roberts M P Clemens J D. Origin of high-potassium calcalkaline I-type granitoids[j]. Geology : [35] Altherr R Holl A Hegner E et al. High-potassium calc-alkaline I -type plutonism in the European Variscides: northern Vosges [R] (in Chinese). [22] Peccerillo A Taylor S R. Geochemistry of Eocene calc -alkaline (France) and northern Schwarzwald 50: (Germany) [J].Lithos 2000 volcanic rocks from the Kastamonu area northern Turkey [J]. Contribution to Mineralogy and Petrology : [23] Maniar P D Piccoli P M. Tectonic discrimination of granitoids[j]. Geological Society of American Bulletin : [24] Whalen J B Currie K L Chappell B W. A -type granites: [36] Barker F Farmer G L Ayuso R A et al. The 50 Ma granodiorites of the eastern Gulf of Alaska: melting in an accretionary prism in the forearc[j]. Journal of Geophysic Research : [37] Rogers G Hawkesworth C J. A geochemical traverse across the North Chilean Andes: evidence for crust generation from the geochemical characteristics discrimination and petrogenesis [J]. mantle wedge [J]. Earth and Planetary Science Letters : Contribution to Mineralogy and Petrology : [25] Sun S S McDonough W E. Chemical and isotopic systematics of ocean basalt:implication for mantle composition and processes[c]// [38] Sajona F G Maury R C Bellon H et al. High field strength elements of Pliocene -Pleistocene island -arc basalts Zamboanga Saunders A D Norry M J (eds.). Magmatism in the ocean basins. Peninsula Western Mindanao (Philippines) [J]. Journal of Geological Society of London Special Publication : [26] Green T H. Significance of Nb /Ta as an indicator of geochemical Petrology : [39] Pearce J A. Sources and settings of granitic rocks[j]. Episodes : processes in the crust-mantle system [J]. Chemical Geology 1995 [40] Xie Caifu Zhu Jinchu Ding Shijiang et al. Identification of 120: Hercynian shoshonitic intrusive rocks in central Hainan Island and

Chuaria-Tawuia [28] Bea F Arzamastsev A Montero P et al. Anomalous alkaline rocks [J]. (B ) 1989 (3) 304-311. of Soustov.

12 39 6 : 1711 its geotectonic implications [J]. Chinese Science Bulletin (20) : in Hainan Island and its geotectonic implications [J]. Geological Review (4): (in Chinese with English abstract). [41]. [43] Hoa T T Anh T T Phuong N T et al. Permo -Triassic [J] (3): intermediate felsic magmatism of the Truong Son belt eastern Shu Bin Wang Pingan Li Zhongjian et al. Research on margin of Indochina [J]. C.R.Geosciences : mineralizing age of Baolun gold deposit in Hainan Province and its significance[j]. Modern Geology (3): (in Chinese with English abstract). [44] Lan C Y Chung S L Shen J J S et al. Geochemical and Sr-Nd isotopic characteristics of granitic rocks from northern Vietnam[J]. Journal of Asian Earth Sciences : [42]. - [45] Lepvrier C Maluski H Nguyen V V et al. Indosinian NW - [J] (4): trending shear zones within the Truong Son belt (Vietnam): 40 Ar- Zhou Zuomin Xie Caifu Xu Qian et al. Geological and 39 Ar Triassic ages and Cretaceous to Cenozoic overprints [J]. geochemical characteristics of Middle Triassic syenite-granite suite Tectonophysics : Origin and rock-forming environment of the granitoids in the periphery of the Shilu iron deposit YU Jin-jie 1 CHEN Fu-xiong 2 WANG Yong-hui 2 LIANG Jiang 2 CHE Lin-rui 3 (1. MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing China; 2. Hainan Mining United Co. Ltd. Changjiang Hainan China; 3.China University of Geosciences Beijing China) Abstract:The Indosinian granites in the periphery of the Shilu iron deposit belong to the Changjiang granitic body. These granites are mainly monzonitic granites. They lie between metaluminous field and weakly peraluminous field and belong to high-k calc-alkaline series and shoshonitic series. The granites have REE values of ppm and show relatively strong enrichment of light rare earth elements (LREE/HREE= ) with higher (La/Yb) N ratios of and negative Eu anomalies (δeu= ). Mantlenormalized trace element spidergrams of all samples show obvious negative anomalies of Ba Nb Ta Ce Sr P and Ti. The obvious negative Ba Sr and Eu anomalies indicate that plagioclase existed in the source region or the granites experienced plagioclase crystallization and fractionation. The granites have a range of ( 87 Sr/ 86 Sr) i from to except for one sample (SL10-136) whose ( 87 Sr/ 86 Sr) i value is a narrow ε Nd (t) value range of -7.3 to -9.1 and T DM2 model ages of Ga indicating a homogeneous source and partial melting of the Mid -Proterozoic Baoban Group. The granites were formed in a post -orogenic environment. Based on previous investigation of granite in Hainan Ireland this paper deals with ireland-arc syn-orogenic and post -orogenic granitoids in Hainan Ireland. The Hercynian to Indosinian granitoids can be compared with granitoids in northern Vietnam. Key words:indosinian granites;post -orogenic environment;partial melting;periphery of the Shilu deposit; Hainan Island About the first author:yu Jin -jiemale born in 1966 doctor senior researcher engages in the study of metallic mineralization; yjjchina@sina.com.

intermediate felsic magmatism of the Truong Son belt eastern Shu Bin Wang Pingan Li Zhongjian et al. Research on margin of Indochina [J]. C.R.Geosciences 2008 340:112-126.

2011 2 89 Table 1 1 U-Pb U-Pb isotopic determinations of zircon in quartz diorite from the Jiarongjiandegongka intrusive rocks 1 Qh al pal - Qp 3 - TB

2011 2 89 Table 1 1 U-Pb U-Pb isotopic determinations of zircon in quartz diorite from the Jiarongjiandegongka intrusive rocks 1 Qh al pal - Qp 3 - TB 31 3 2011 9 Sedimentary Geology and Tethyan Geology Vol. 31 No. 3 Setp. 2011 1009-3850 2011 03-0088-07 430205 - - - Rb K Ba Th Sr Nb Ta Ti P P588. 1 A 1990 1 20 1 25 40 ~ 50 2 5cm 15 30cm 10 ~ 20mm 100