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1 DOI: /j.ddgzyckx (Volume)42, (Number)4, (SUM)165 (Pages)651~663, 2018, 8(August, 2018) 大地构造与成矿学 Geotectonica et Metallogenia 地质和硫碳氧同位素制约杨光树 1, 温汉捷 2, 胡瑞忠 2, 范良伍 3, 燕永锋 1, 毛致博 1, 王凯 1 (1., ; 2., ; 3., ) 摘要 :,,,, δ 34 S 6.5 ~10.6,,, ;, δ 34 S V, δ 13 C 5.5 ~2.0,,, δ 13 C δ 18 O, δ 18 O,,,,, 关键词 : ; ; ; ; 中图分类号 : P611 文献标志码 : A 文章编号 : (2018) 引言 (), 326, 5164, 50%,, (, 1991;, 1992;, 1993;, 1998) (, 1996;, 2005; Zhou et al., 2007) (Sun et al., 2003;, 2004;, 2008;, 2012;, 2017;, 2017)(Liu et al., 2011, 2012;, 2016),, : (1),, (Pan and Dong, 1999;, 2004; Zhou et al., 2007;, 2012;, 2013); (2) (, 1993;, 1996;, 1998;, 收稿日期 : ; 改回日期 : 项目资助 : ( ; ) (2017YFC ) 第一作者简介 : (1980 ),,, @163.com

2 652 第 42 卷 1998;, 1998); (3) (, 2012;, 2013),, 1 地质背景与矿床特征 1.1, ( 1), (T 1 n):,,, (, 2016)(T 2 y):, ; (T 2 t): (T 3 l):,, (, 2013) ( ) (, 2005),, ( 1),, ( 1), 11 km 2,,, Fe-Cu(Au) Y, ( 1) U-Pb 138.7± 0.5 Ma(, 2008) 139.3±1.5 Ma(, 2009), 1.2,, 900 m, 4000 ( 1), 1.18%, 45% Pt. ; Z-S. ; D-T. ; J. : 1. ; 2. ; 3. ; 4. ; 5. ; 6. 1 (, 1993 ) Fig.1 Sketch geological map of the Yueshan orefield

第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化 653 表 1 安庆铜矿主要矿体特征 (, 2008) Table 1 The characteristics of main ore bodies in the Anqing Cu-Fe deposit (m) (m) (m) ( 10 4 t) ( 10 4 t) (m) (m) 1 Cu-Fe >1000 400~600 28

3 第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化 653 表 1 安庆铜矿主要矿体特征 (, 2008) Table 1 The characteristics of main ore bodies in the Anqing Cu-Fe deposit (m) (m) (m) ( 10 4 t) ( 10 4 t) (m) (m) 1 Cu-Fe > ~ >2340 > Cu-Fe Cu ~ Fe-Cu F 1 F 6, (2 ) (1 )( 2a), 1 S,, ( 2b),,, ( 2, 2), ;, ;,,,, ( 3), :,, ( 2),, ( 3a), 表 2 安庆铜矿与典型矽卡岩铜矿床分带特征对比 Table 2 Zoning of mineralization in the Anqing Cu-Fe deposit and typical skarn-type Cu deposit (1 ) () ( Cu) ( Cu) ( Cu) ( Cu) m (a) 1 1 (b)(, 2008 ) Fig. 2 Distribution of the ore bodies in 400 m (a) and the 1 cross section of No.1 ore body (b) form the Anqing copper-iron deposit

黄铁矿叠加于早期矽卡岩上矿物代号: Di. 透辉石; Gr. 石榴子石; Mb. 大理岩; Mt. 磁铁矿; Cp. 黄铜矿; Po. 磁黄铁矿; Py. 黄铁矿 Fig.

4 654 第 42 卷 w w / / p:. x ck y z dg d. w / m o c t t h (a) 外带磁铁矿体与大理岩呈截然接触, 界线清楚(据范良伍, 2008); (b) 块状磁铁矿体中不规则状碳酸盐脉和团块; (c) 含铜石榴子石矽卡岩; (d) 细粒磁铁矿沿环带状石榴子石的裂隙和边缘充填交代(单偏光); (e) 后期含硫化物矽卡岩脉穿插交代早期矽卡岩和磁铁矿(单偏光); (f) 浸染状黄铜黄铁矿叠加于早期矽卡岩上矿物代号: Di. 透辉石; Gr. 石榴子石; Mb. 大理岩; Mt. 磁铁矿; Cp. 黄铜矿; Po. 磁黄铁矿; Py. 黄铁矿 Fig. 3 图 3 安庆铜矿矿石结构构造特征 Textures and structures of the ores in the Anqing Cu-Fe deposit 间常穿插灰白色碳酸盐细脉(图 3b) 石榴子石矽卡短柱状, 常与石榴子石共生, 被较晚的脉状钙铁辉岩多具有中粗粒结构, 石榴子石成分主要为钙铁石透闪石以及金属硫化物穿插交代(图 3e) ②热榴石, 常呈自形粒状(图 3c), 暗红褐色, 环带结构和液硫化物期, 包括石英硫化物阶段和石英碳酸盐裂理发育, 沿裂理常被细粒磁铁矿充填交代 (图 3d); 阶段, 是铜矿的主成矿阶段大量浸染状脉状金石榴子石矽卡岩中常叠加有后期一些浸染状黄铁属硫化物(黄铜矿黄铁矿磁黄铁矿等)形成, 并沿矿磁黄铁矿和黄铜矿等 (次)透辉石矽卡岩主要产早期矽卡岩和磁铁矿裂隙充填交代, 构成了矽卡岩型于内接触带, (次)透辉石呈浅绿色, 中细粒半自形铜矿体(图 3f)和含铜磁铁矿体, 早期形成的矽卡岩

5 第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化 655,, ;,,,,, 2 样品与分析方法, 520 m 1 ( 2b),, m (CK20-6 CKW1-4), 60~80,, 99%,, :, >99%, 200, ( 1 10, 1 8), Pa,, SO 2, 1000 ; SO 2, MAT252, CDT, δ 34 S, ±0.2, :, 100% 25 4 h,, CO 2, MAT253, PDB, δ 13 C PDB δ 18 O, ±0.2 3 测试结果表 3 安庆铜矿硫化物硫同位素组成 Table 3 Sulfur isotopic compositions of sulfide separates from the Anqing skarn-type Fe-Cu deposit δ 34 S ( ) δ 34 S ( ) A Po A Py A 2 Po 5.81 A 363 Py 4.72 A Po X 7 Py 4.59 A Po A 354 Py 3.78 X 3 Po 3.66 A 5 Py 3.23 A Po Y 114 Py 0.71 A T-Z Po A 4 Py 1.00 Y 200 Po 6.11 A 7-y Py 1.37 A 12 Py 6.71 A 8 Cp 9.75 A Py A Cp 11.2 X 2 Py A Cp 8.32 Y 363 Py AQ m Cp 1.60 A 10 Py 9.08 AQ m Cp 6.80 A Py 9.48 AQ m Cp 5.20 Y 117 Py 5.34 AQ m Cp 3.60 X 5 Py 4.49 AQ m Py ~4.80 AQ m Py AQ m Py ~34.41 AQ m Py ~9.00 AQ m Cp 2.40 Py 9.00 AQ m Py 1.10 Py AQ m Py 1.60 ZK26 Py 16.70~ AQ-12 CKW1 Py 8.40 Q-Py Py 3.40 AQ-13 CKW1 Py ~ AQ-14 CKW1 Py Py 4.99~9.62 AQ-15 Py : Cp. ; Py. ; Po. ; AQ-1~15, (2005)

6 656 第 42 卷 4 () δ 13 C PDB 5.50 ~2.00, (ACK26-96) δ 13 C PDB ( 5.50 ), (δ 13 C PDB 3.70 ~ 2.50, 3.03 ); δ 13 C PDB ( 2.80 ~2.00, 0.40 ), δ 13 C PDB (1.50 ) (A1Cp-C1) δ 13 C PDB ( 0.90 ) 13 C PDB ( 0.50 ~ 0.10, 4 Fig. 4 Histogram of sulfur isotopic compositions of sulfides from the Anqing Fe-Cu deposit : (1) δ 34 S, δ 34 S 6.50 ~13.00, 4.00, 10 ( 4), (Py) δ 34 S 6.50 ~1.6, (Cp) 5.20 ~6.80 Ohmoto (1972),, δ 34 S 1 ~3, 250~600, Py Cp Po Δ ( ) 0.15~0.45 δ 34 S,, (δ 34 S s ) (2) δ 34 S 3, δ 34 S 4.25, δ 34 S 0.30, δ 34 S 8.00 ;, 34 S (3), 34 S, 34 S, δ 34 S ( 4.75 ), ( 9.00 ), 20 (2005) δ 34 S 9.48 ~ ~1.50, 30 δ 34 S ( 3, 4), ),, δ 13 C PDB 1 δ 18 O SMOW (16.50 ~21.21, ) (6.33 ~17.50, ) (7.0 ), δ 13 C PDB ; (9.8 )(10.85 ) ( 8.25 ), δ 18 O SMOW (4.25 ) 4 讨论 4.1 Hoefs(2009), : ; (ph ); ; (W/R ), (1987), ( ph ) ; (2005) (W/R ) δ 34 S,, 6 : + +, 78%, 22%,,,,,,,,

7 第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化 657 Table 4 表 4 安庆铜矿大理岩和方解石碳氧同位素组成 Carbon and oxygen isotopic compositions of the marbles and calcites from the Anqing skarn-type Fe-Cu deposit δ 18 O( ) δ 18 O( ) δ 18 O ( ) δ 13 C PDB ( ) G-1 () Z Z Z m () Z Z-5 (6 ) Z-6 (20 ) Z-7 (7 ) TZ-1 (4 ) TZ TZ TZ TZ-5 () TZ A1T1n m () AM18-K11 ZKW18-4 () AM m () AZKW ZKW () AM m AM m AQF mf AM m AM m AMZL m A1Cp-C m ACK : G-1 (2000); Z-1~7 (1997); TZ-1~6 Zhou et al.(2007); δ 18 O 1000lnα - = /T /T+1.71 (, 1999), T () (, 2008) 260~300, ph 5.1~6.7, (lgf O2 = 18~ 25) (lgf O2 = 23~ 35)(Zhou et al., 2007,, 2008;, 2013) (2005),,, ph, SO 2 /H 2 S δ 34 S, H 2 S,, 5,, ( 5a), δ 34 S 0~3, (Pan and Dong, 1999) δ 34 S 6.5 ~6.8, ( 4),, (),, δ 34 S ~34.41, δ 34 S >25 ( 3), δ 34 S 3.50 ~4.80,, δ 34 S ~ 31.06, (, 1986;, 2014;, 2014) (, 1980;, 2004;, 2013;, 2013), δ 34 S,,

8 658 第 42 卷 δ. ; δ-cu. ; SK-Cu. ; SK-Cu(Fe). ; SK-Fe. Pan and Dong (1999) (2005) 5 (a) 1 δ 34 S (b) Fig. 5 δ 34 S values of the representative skarn-type deposits from the Tongling-Anqing district (a) and average δ 34 S values in the mineralization zonings of the Anqing Fe-Cu deposit (b), δ 34 S 2.0,, δ 34 S (3.50 ~4.80 ), δ 34 S,,, 3 (AQ-12~14) (AQ-1, 2) δ 34 S, δ 34 S,,,, AQ-1, 2, 11, δ 34 S ( 6.5 ~ 1.1 ), ( 3),,,, (δ 34 S ~ ),,,,,, δ 34 S, δ 34 S m ( 5b), δ 34 S V,, δ 34 S, δ 34 S (1987) δ 34 S ph,, δ 34 S, δ 34 S, δ 34 S,, δ 34 S 200, (ph=5.1~6.7), (logf O2 >10 32 ), ph f O2, δ 13 C PDB δ 13 C PDB (Ohmoto, 1972) δ 13 C PDB ( 5.50 ) δ 13 C PDB ( 8 ~ 5 )(Hoefs, 2009), ; δ 13 C PDB 0.40, δ 13 C PDB (0 ), δ 13 C PDB 3.03,, δ 13 C PDB (1.50 ),,,,, CO 2,

9 第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化 659 δ 18 O SMOW, (Bowman, 1998; Pan and Dong, 1999;, 2015) δ 18 O SMOW ,,,,, CaO MgO CO 2, δ 13 C PDB δ 18 O SMOW, δ 18 O SMOW (, 2000) δ 18 O 0.93 ~7.43, 5 ~7, ( 5.5 ~8.5, Ohmoto, 1972), ( 10, Pan and Dong, 1999), δ 18 O SMOW , (8.25 ) (9.80 ) (14.80 ), δ 18 O SMOW,, δ 18 O SMOW -δ 13 C PDB ( 6), ( ),, (ACK26-96),, (Zhou et al., 2007) TZO-1, (Veizer and Hoefs, 1976;, 1999),,,,, ;, δ 13 C δ 18 O SMOW, δ 18 O SMOW 4.2 ( ),,,, (Xu et al., 2004;, 2012; Xie et al., 2012; Wang et al., 2015; Xu et al., 2015), ( ) ( 1) U-Pb (138.7±0.5 Ma,, 2008) Re-Os 137.4±2.2 Ma(, 2004) Os-Os 136.1±2.0 Ma (Sun et al., 2003),,,, (2002) Zhou et al. (2007), 6 δ 18 O SMOW - δ 13 C PDB (, 2004) Fig. 6 δ 18 O SMOW vs. δ 13 C PDB plot for calcites and marbles from the Anqing Cu-Fe deposit

10 660 第 42 卷 (2012) (2013) (1995) (2011), (1996) (1993) (2015), (2008) (2012),, Fe 2 O T 3 SiO 2 Al 2 O 3, ; CaO MgO,,, (Einaudi et al., 1981; Meinert, 1997;, 2002; Meinert et al., 2005) (2013),,,,,,, 500, ( ) ( 2), ( ), ( 3a, b), ( ), ( 2),, (, 2013), (2012),, REE ; (1995) 500, (1993)(1998), (),, Sr-Nd-Pb ( ),, δ 18 O,,,, SiO 2 MgO, Fe 2 O T 3 ( 7),, Mg Si, Fe, (, 2008;, 2008) Fe 2 O T 3 4.8% 4.7%,, Fe Cu 1(, 2007),, ( 7),,,,, 260~300 (, 2008;, 2013), 7 1 Fig. 7 Variation curves of major elements in the No.1 ore body of the Anqing Cu-Fe deposit

11 第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化结论 (1) δ 34 S, 6.5 ~10.6, V,,, (2) δ 13 C PDB 5.5 ~2.0,,,, ; δ 13 C PDB δ 18 O SMOW, δ 18 O SMOW δ 18 O SMOW, (3),, 致谢 : 铜陵有色金属集团股份有限公司和安庆铜矿在野外工作中给予了大力支持, 两位匿名审稿专家对稿件进行了耐心细致审阅, 并提出了宝贵的修改建议, 在此一并深表感谢! 参考文献 (References): , (2) : ,, : : ,,, ( ), 44(2): ,,,, U-Pb Hf., 41(3): ,, , 26(3): , : : ,,,,, , 19(2): ,,,, , 85(5): ,, , 28 (4): ,, , 21(1): ,,,,,, :., 23(3): ,,,,,,, , 30(5): ,,,, , 87(9): , 12(4): , :., 28(4): ,, , 23(1): 1 10.,, U-Pb Hf., 28(5): , Holly STEIN, ( ) Re-Os., 78(1): , : : , 23(3): ,, : : ,,,,, , 32(3): ,,,, Hf :., 27(1): , , 31(3):

12 662 第 42 卷, , 5(4): ,, , 6(2): ,,,,,,, , 34(2): ,,,,, SHRIMP U-Pb., 30(1): ,, , 27 (3/4): ,, , 37(1): ,,, , 20(3): ,, ( ). : : ,, SHRIMP U-Pb., 24(8): ,,,,,, :., 28(11): , ( )., 26(5): , , 38(21): ,,,,, , 31(4): , 21(2): 赵一鸣中国主要富铁矿矿床类型. 矿床地质, 32(4): : : ,,,,,,,,, Noel WHITE , 88(4): , , 15(4): ,, : : ,,,, :., 87(9): ,,, (CSAMT)., 35(2): Bowman J R Stable isotope systematics of skarns// Lentz D R. Mineralized Intrusion Related Skarn Systems. Mineralogical Association of Canada, Short Course 26. Ottawa: Einaudi M T, Meinert L D and New berry R J Skarn deposits. Economic Geology, 75th Anniversary volume: Hoefs J Stable Isotope Geochemistry (sixth edition). Springer-Verlag Berlin Heidelberg, Liu L M, Wan C L, Zhao C B and Zhao Y L Geodynamic constraints on orebody localization in the Anqing orefield, China: Computational modeling and facilitating predictive exploration of deep deposits. Ore Geology Reviews, (43) 1: Liu L M, Zhao Y L and Sun T D computational shape- and cooling process-modeling of magmatic intrusion and its implication for genesis and exploration of intrusion-related ore deposits: An example from the Yueshan intrusion in Anqing, China. Tectonophysics, : Meinert L D Application of skarn deposit zonation models to mineral exploration. Exploration and Mining Geology, 6(2): Meinert L D, Dipple G M and Nicolescu S World skarn deposits. Economic Geology, one hundredth anniversary volume: Ohmoto H Systematics of sulfur and carbon isotopes in hydrothermal ore deposits. Economic Geology, 67: Pan Y M and Dong P The Lower Chanjiang (Yangtzi/ Yangtze River) metallogenic belt, east central China: intrusion and wallrock-hosted Cu-Fe-Au, Mo, Zn, Pb, Ag deposits. Ore Geology Reviews, 51: Sun W D, Xie Z, Chen J F and Zhou, T F Os-Os dating of copper and molybdenum deposits along the Middle and Lower reaches of the Yangtze River, China. Economic Geology, 98: Veizer J and Hoefs J The nature of 18 O/ 16 O and 13 C/ 12 C secular trends in sedimentary carbonate rocks. Geochimica et Cosmochimica Acta, 40: Wang S W, Zhou T F, Yuan F, Fan Y, Zhang L J and Song Y

13 第 4 期杨光树等 : 安徽安庆铁铜矿床物质来源与演化 663 L Petrogenesis of Dongguashan skarn-porphyry Cu-Au deposit related intrusion in the Tongling district, eastern China: Geochronological, mineralogical, geochemical and Hf isotopic evidence. Ore Geology Reviews, 64: Xie J C, Yang X Y, Sun W D and Du J G Early Cretaceous dioritic rocks in the Tongling region, eastern China: Implications for the tectonic settings. Lithos, 150: Xu X S, Fan Q C, O Reilly S Y, Jiang S Y, Griffin W L, Wang R C and Qiu J S U-Pb dating of zircons from quartz diorite and its enclaves at Tongguanshan in Anhui and its petrogenetic implication. Chinese Science Bulletin, 49: Xu Y M, Jiang S Y, Zhu Z Y and Zhou W Mineral chemistry and H-O-S-Pb isotopic compositions of skarn type copper deposits in the Jiurui district of the Middle-Lower Yangtze River metallogenic belt, Eastern China. Ore Geology Reviews, 69: Zhou T F, Yuan F, Yue S C, Liu X D, Zhang X and Fan Y Geochemistry and evolution of ore-forming fluids of the Yueshan Cu-Au skarn-and vein-type deposits, Anhui Province, South China. Ore Geology Reviews, 31(1 4): Sources and Evolution of the Ore-forming Materials in the Anqing Cu-Fe Deposit in Anhui Province Geological and S, C, O Isotopic Constraints YANG Guangshu 1, WEN Hanjie 2, HU Ruizhong 2, FAN Liangwu 3, YAN Yongfeng 1, MAO Zhibo 1 and WANG Kai 1 (1. Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming , Yunnan, China; 2. Institute of Geochemistry, Chinese Academy of Science, Guiyang , Guizhou, China; 3. Beijing Sinoking Resource Company, Beijing , China) Abstract: The Anqing Cu-Fe deposit is one of the representative large Cu-Fe deposits along the Yangtze River in Anhui province, with controversial metallogenic mechanism. Based on the ore-forming geological characteristics, this paper focus on the sulfur, carbon and oxygen isotopic compositions of the ores and surrounding rocks, and discuss the sources and evolution processes of the ore-forming materials. The Cu-Fe deposit occurs in the contact zone between the early Yanshanian Yueshan diorite and Triassic marble, with clear horizontal zonings in the skarns and ore bodies. The garnet skarn and thick massive magnetite ore body commonly occur within the external contact zone, which have clear boundaries with the surrounding rocks; whereas the diopside skarns with disseminated copper sulfide commonly occur within the internal contact zone and show gradual and transitional relations with the diorite. The δ 34 S values of the ores range from 6.5 to 10.6, and show a V-shaped trend from the diorite to the outer marble. This compositional variation indicates that most of the sulfur may come from magma, with involvement of some pre-triassic clastic strata sulfur and Triassic marine sulfates in the later stage. The δ 13 C values of the gangue minerals range from 5.5 to 2.0, which decrease from the external contact zone to internal contact zone, indicating that the carbons of the ore-forming fluids may be mainly derived from magma, with some Triassic carbonate stratigraphic carbon involved. The marbles nearby the orebody show δ 18 O values lower than those of the Triassic strata, indicating that they have been remolded by the low δ 18 O magmatic hydrothermal fluids. The magnetite have some magma filling geological features and extremely low δ 18 O value, may be the result from the filling of the high temperature iron-rich fluids along the contact zone and fault. This study shows that the ore-magma filling type and hydrothermal-metasomatic type ore bodies coexist in the Anqing Fe-Cu deposit. The immiscibility between iron oxide and silicate melt occurred in magma chamber, which resulted in the formation of iron-rich fluid. The fluid migrated upward and eventually precipitated in a favorable tectonic area or contact zone, and the magnetite ore bodies were formed in the outer contact zone. By the later fluid mixing, filling metasomasis, and water-rock reaction between the differentiated hydrothermal solutions and diorite, the copper ore bodies and the copper-bearing altered diorite were formed in the internal contact zone. Keywords: Anqing Cu-Fe deposit; skarn; sulfur, carbon, oxygen isotope; ore-forming process; ore-forming material sources

km 5 km Pt 2 x 2 1 Au 65 ~ ~ km 5 km 10 km 2 Au Au

km 5 km Pt 2 x 2 1 Au 65 ~ ~ km 5 km 10 km 2 Au Au 38 1 2015 3 JOURNAL OF EAST CHINA INSTITUTE OF TECHNOLOGY Vol. 38 No. 1 Mar. 2015 doi 10. 3969 /j. issn. 1674-3504. 2015. 01. 002 1 2 1 2 3 1. 471000 2. 471000 3. 510640 9 P618. 51 A 1674-3504 2015 01-0012-11.