Geochronology Geochemistry and Petrogenesis of the Granite and Diorite in Wusun Mountain Western Tianshan
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摘要:
笔者选取位于伊犁盆地内乌孙山北缘察布查尔林场花岗岩为研究对象,其地球化学、地质年代学和岩石成因研究对于探讨西天山南缘壳幔岩浆作用具有较重要的指示意义。岩石地球化学特征显示二长花岗岩属高钾钙碱性准铝质-弱过铝质岩石系列;轻稀土富集,弱的Eu负异常(δEu=0.74~0.84),富集大离子亲石元素,亏损Nb、Ta、P、Ti等高场强元素特征,Zr/Hf=42~44,部分样品中含有少量的刚玉标准矿物,显示出壳源花岗岩的特征。闪长岩Al2O3、FeOT、CaO含量明显高于二长花岗岩,Na2O和K2O含量低于二长花岗岩,属于高钾准铝质岩石系列;轻稀土富集,显示出Eu的轻微正异常(δEu=0.90~1.24),富集大离子亲石元素,亏损Nb、Ta等高场强元素,此外,闪长岩还显示出具有高Sr(Sr>400×10−6)低Y(12.83×10−6)及Yb(1.34×10−6)和高Mg#特征,其源岩应为俯冲板片上覆地幔部分熔融产物。二者均显示出岛弧岩浆的特征。二长花岗岩锆石U-Pb年龄为(361.7±1.8) Ma;形成于晚泥盆世末期,结合前人的研究资料认为在~360 Ma由于南天山洋板片的回撤或俯冲流体参与,上覆地幔发生部分熔融产生了基性岩浆,岩浆上涌过程中提供大量的热导致地壳发生部分熔融形成了酸性岩浆,两种岩浆发生不均匀混合作用。上涌的岩浆引起地幔对流,导致伊犁地块内部出现一定的伸展作用(弧后伸展作用)。
Abstract:The study object is located in the Chabuchaer Forest Farm on the northern margin of Wushun Mountain in Yili Basin, the studying of geochemistry, geochronology and petrogenesis have an important indicative significance for discussing crust-mantle magmatism in the southern margin of the West Tianshan. The geochemical characteristics show that the monzogranites is a high-potassium-calcium-alkaline and quasi-aluminous-weak peraluminous rocks, the monzogranites is enriched with LREE、weak negative Eu anomaly (δEu=0.74~0.84)、rich in LILEs and deficient in HFSEs(Nb、Ta、Ti、P), its Zr/Hf radios are 42~44, some samples contain a small amount of corundum mineral, and it show the characteristics of crust-derived granite. The Al2O3, FeOT and CaO of the diorite is obviously higher than that in granite, but the Na2O and K2O is lower than the granite, it belongs to high-potassium-calcium-alkaline quasi-aluminous rock; the diorite is enriched with LREE、weak positive anomaly of Eu(δEu=0.90~1.24)、rich in LILEs and deficient in HFSEs(Nb、Ta), in addition, the diorite has high Sr (Sr>400×10−6), low Y (12.83×10−6) and Yb (1.34×10−6) and high Mg#, therefore, the source rock is the partial melting product of the mantle overlying the subduction slab, which enrichment hornblende. The monzogranite and diorite show the characteristics of island arc magma. The zircon U-Pb dating results show that the age of monzogranite is 361.7±1.8 Ma, and belong to the late Devonian. Combined with previous research data, we believed that in ~360 Ma, due to the rolling-back or subduction of the southern Tianshan ocean plate, the overlying mantle partially melted and produced the basic magma. During the uppouring process of the magma, a large amount of heat were provided, which led to partial melting of the crust and the formation of acidic magma, and the two kinds of magma had uneven mixing. At the same time, mantle convection caused by upwelling magma leads to a certain extension (back-arc extension) in the Yili block.
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Keywords:
- Western Tianshan /
- granite and inclusion /
- zircon U-Pb dating /
- geochemistry /
- tectonic environment
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大别造山带是中国研究程度较高的高压−超高压变质带之一,也是2个陆−陆碰撞造山后,中生代的岩浆活动之最强烈地区(Ma et al.,1998)。前人的研究表明,大别造山带在早白垩世发生了大规模岩浆活动(120~138 Ma) (李曙光等,1999;Jahn et al.,1999;Xu et al.,2007;穆可斌等,2019;张凯等,2020) , 侵入的岩体主体为中酸性岩,镁铁−超镁铁质岩次之,大量与其年代相近的中酸性、基性脉岩穿切岩体(王世明等,2010)。中基性岩脉的研究对于了解区域的壳幔相互作用及构造环境具有十分重要的意义。
基性岩浆能反映地幔源区性质,成因环境和形成演化过程,能为底侵以及壳幔岩浆相互作用提供可靠信息,对大别地区镁铁–超镁铁质岩石为碰撞后侵入岩的认识已逐渐统一(Hacker et al.,1995;Hacker et al.,1998 ;葛宁洁等,1999;赵子福等,2003),但对于大别基性岩岩浆来源存在较大分歧: ①认为地幔和地壳混合形成(戚学祥等,2002)。②由俯冲的扬子岩石圈地幔部分熔融产生(赵子福等,2003; Zhao et al.,2005 )。上述岩浆来源的地质构造背景,前人将之归纳成3种观点:①观点认为陆−陆碰撞造山后环境形成于三叠纪时期(Chen et al.,2002;Xu et al.,2007)。②认为不是三叠纪时期的陆−陆碰撞,可能与中国东部的岩石圈发生减薄构造事件有关,是由太平洋板块在晚中生代时期西向俯冲导致的(任志等,2014;刘清泉等,2015)。③认为可能与岩石的部分熔融有关,该部分熔融是由地幔柱在早白垩世时期对岩石圈热扰动所引起的 (赵子福等,2004)。针对大别基性岩的岩浆源区性质及大地构造背景的认识还存在的差异,笔者以翔实的野外观察为基础,通过研究大悟地区出露的闪长玢岩脉地球化学特征,结合野外闪长玢岩脉穿切花岗斑岩脉的地质事实,分析闪长玢岩的岩浆源区性质及所处大地构造环境,探讨大别造山带的壳−幔相互作用。
1. 区域地质背景
秦岭–大别造山带是扬子地块在三叠纪时期与华北地块发生俯冲–碰撞,而产生的高压–超高压变质带,东被郯城–庐江断裂所截,北连华北克拉通,南为扬子地块(图1)。在大悟地区早白垩世时期基性脉岩侵位分布广泛,种类较多,包括辉绿(玢)岩、煌斑岩、辉长岩、闪长玢岩等,有的基性脉岩切割或穿插晚中生代时期的中酸性岩体,基性岩脉的走向分布主要为北东东,北西向脉岩占据部分,岩脉倾角均较陡,与其围岩的接触界线清晰(王世明等,2010)。
图 1 大别山地区构造简图(据索书田等,1993修改)1. 新元古代木兰山−张八岭蓝片岩带;2. 中元古代随县千枚岩带;3. 古元古代—中元古代大悟−宿松−连云港含磷岩带;4. 新太古代桐柏−大别−胶南杂岩带;5. 燕山期花岗岩;6. 断裂Figure 1. Structural sketch of Dabie Mountain area闪长玢岩脉分布规模小,出露宽度为10~25 cm,延伸长度一般为1~3 m,围岩岩性主要为马吼岭群白云钠长石英变粒岩(图2a),个别闪长玢岩脉交截花岗斑岩脉(图2b)。
2. 岩相学和矿物学特征
闪长玢岩表现为黑色或黑褐色,具斑状结构,呈块状构造。斑晶成份几乎为暗色矿物,少量基性斜长石,斑晶总量约为20%,暗色矿物绝大多数被碳酸盐矿物、绿泥石交代为残余柱状、六边形假象(属角闪石),极少数被绿泥石、白云母交代为残余片状假象(属黑云母)。基性斜长石发生交代作用被碳酸盐矿物所取代,呈现出残余柱状构造的型式。
基质总量约为80%,成分主要由具碳酸盐化、钠黝帘化残余自形小板条状的基性斜长石组成,许多玻璃质充填三角形空隙格架内,无序分布(在单偏光下显浅褐色,外形呈隐晶集合体,在正交偏光下显黑色并具均质性全消光)、暗色矿物及少量的铁质矿物(种类有磁铁矿和钛铁矿)、微量的石英而组成变余间隐间粒结构的特征(图2c)。岩石中还可见一颗外形呈不规则状的杏仁体,沿其内充填着粗大粒状的石英晶体(图2d)。
3. 样品采集及分析测试方法
野外采集新鲜的闪长玢岩样品,在自然资源部武汉矿产资源检测中心完成样品的主量元素、微量元素及稀土元素的测试,利用X射线荧光光谱分析熔铸玻璃片法分析主量元素,分析仪器的型号为XRF-1500,对于分析精度要求精于1%,FinningMAT公司生产的等离子质谱仪(ICP−MS)测定样品中的微量元素、稀土元素,分析精度要求高于5%。
4. 岩石地球化学特征
4.1 主量元素特征
闪长玢岩 (样品D2073/1、D2073/2、D2073/3、D2073/4、D2073/5和D4078/4)的主量元素和微量元素分析结果显示,SiO2含量为49.97%~55.01%,属于基性−中基性成分,样品号为D2073/2、D2073/3的SiO2含量较高,可能与脉岩侵位过程中与花岗斑岩发生交代作用有关。MgO含量为4.63%~5.49%,Al2O3含量为14.01%~14.65%,P2O5 含量为0.52%~0.80%,CaO 含量为 4.70%~6.17%,K2O含量为3.41%~4.39%,Na2O含量为1.82%~3.86%,岩石富碱,K2O/Na2O值为 0.41~1.11(表1)。样品中MgO含量与SiO2 含量相反,随之增高而降低,Al2O3、P2O5含量随SiO2含量增高而升高,表现出岩浆分异演化的一般规律。
表 1 闪长玢岩主量元素、微量元素、稀土元素分析结果表Table 1. Analysis results of major elements, trace elements and rare earth elements of diorite porphyrite样号 D2073/1 D2073/2 D2073/3 D2073/4 D2073/5 D4078/4 BZK21-02 BZK21-03 BZK21-04 岩性 闪长玢岩 Na2O 1.82 3.78 3.86 2.12 3.57 1.92 4.41 4.6 3.21 MgO 5.38 4.81 4.63 5.16 4.78 5.49 2.24 2.7 3.39 Al2O3 14.04 14.47 14.65 14.11 14.52 14.01 15.18 15.23 17.05 SiO2 49.97 54.64 55.01 52.23 52.06 50.04 52.12 53.24 56.12 P2O5 0.52 0.79 0.8 0.58 0.61 0.54 0.35 0.59 0.51 K2O 4.39 3.41 3.69 3.49 3.52 4.26 3.1 2.93 4.73 CaO 5.93 4.7 5.06 4.65 4.91 6.17 3.33 4.72 1.86 TiO2 1.23 1.15 1.14 1.09 1.12 1.22 0.82 0.84 0.87 MnO 0.15 0.1 0.1 0.11 0.13 0.16 0.32 0.38 0.17 Fe2O3 2.28 0.93 0.93 0.91 0.96 2.37 9.31 6.64 7.45 FeO 5.4 0.79 0.79 0.81 0.8 5.25 4.22 3.9 5.24 H2O+ 3.14 0.28 0.16 0.19 0.25 3.28 CO2 5.25 4.28 LOST 7.83 4.68 3.62 4.57 3.91 7.55 8.27 7.56 4.53 Th 6.72 12.1 12.09 12.05 12.11 5.98 21 19.96 25 Nb 13.94 20.73 20.12 20.69 20.41 12.25 14.6 13.63 17.1 Ta 1.07 1.14 1.14 1.12 1.15 0.81 0.92 0.89 1.1 Sr 625.32 1102.02 1112.55 1107.05 1109.42 670.4 213 254.17 363 Zr 218.8 262.66 258.98 259.13 260.32 223.3 241 229.39 280 Hf 5.09 5.96 5.93 5.95 5.91 5.57 6 5.81 7.17 Eu 1.96 2.53 2.52 2.55 2.57 2.15 1.65 1.52 1.83 Yb 1.46 1.32 1.27 1.31 1.29 1.69 2.23 2.12 2.5 La 45.68 81.43 81.61 81.47 81.58 53.09 44.9 27.19 45.4 Ce 91.52 151.97 153.01 152.03 152.86 97.71 90.9 56.98 95.2 Pr 11.72 16.39 16.31 16.47 16.53 13.37 10.5 6.85 11 Nd 45.71 59.27 59.76 59.35 59.61 51.32 39.6 27.05 42.2 Sm 7.57 9.54 9.31 9.42 9.51 8.57 7.2 5.98 7.6 Eu 1.96 2.53 2.52 2.55 2.53 2.15 1.65 1.52 1.83 Gd 5.89 6.6 6.92 6.83 6.97 6.81 5.28 5.03 5.98 Tb 0.82 0.79 0.78 0.79 0.77 0.96 0.76 0.72 0.82 Dy 3.87 3.88 3.87 3.86 3.89 4.4 4.21 3.86 4.69 Ho 0.7 0.65 0.66 0.64 0.66 0.82 0.83 0.73 0.87 Er 1.69 1.71 1.71 1.75 1.73 2.01 2.29 2.13 2.51 Tm 0.24 0.23 0.22 0.25 0.22 0.28 0.34 0.3 0.38 Yb 1.46 1.32 1.27 1.31 1.29 1.69 2.23 2.12 2.5 Lu 0.22 0.19 0.2 0.18 0.21 0.27 0.35 0.32 0.4 Y 17.3 19.48 19.02 19.43 19.29 20.79 24.7 22.45 26.9 总和 236.35 355.98 357.17 356.33 357.65 264.24 235.74 163.23 248.28 LREE/HREE 9.45 13.62 13.97 13.64 13.79 8.75 6.34 4.48 6.06 (La/Yb)N 21.09 21.18 41.59 43.32 41.93 42.64 13.57 8.65 12.24 δEu 0.87 0.84 0.91 0.93 0.92 0.93 0.81 0.87 0.89 注:主量元素含量%,稀土与微量元素含量10−6 。 4.2 稀土元素特征
闪长玢岩稀土总量为219.04×10−6~338.08×10−6。其中,轻重稀土比为13.29~20.74,平均值为17.05。Zr含量为218.8×10−6~262.66×10−6,Y含量为17.3×10−6~20.79×10−6 (表1),Nb异常值0.16~0.25,(La/Yb)N值为21.21~43.34,表明闪长玢岩轻稀土富集,轻、重稀土分异程度较大,整体表现为右倾型,较陡(图3a)。其中,样品的δEu值为0.84~0.93,负异常不明显,说明斜长石结晶分异作用较弱(刘军等,2022)。大悟地区的闪长玢岩样品脉稀土配分模式总体同安徽庐枞地区的闪长玢岩类似,显示为右倾型特征,稀土模式表明LREE富集、HREE亏损,但庐枞盆地的样品稀土配分更平缓。
图 3 闪长玢岩球粒陨石标准化稀土配分模式(a)和原始地幔标准化微量元素蛛网图(b)庐枞盆地样品转引自汪晶等(2014);球粒陨石和原始地幔标准化值据Mcdonough等(1995)Figure 3. (a) Normalized REE distribution pattern of diorite porphyrite chondrite and(b) primitive mantle normalized trace element spider web4.3 微量元素特征
微量元素蛛网图显示闪长玢岩的微量元素分配型式整体变化趋势相近(图3b),亏损高场强元素Nb、Ta、Hf、Ti,富集元素Gd、Nd、Sr、Th,可能与俯冲板片形成的熔体有关。庐枞盆地闪长玢岩的蛛网图也表现出亏损高场强元素Nb、Ta、Hf、Ti,大离子亲石元素Th等富集,Sr元素不同程度亏损,可能受到了地幔交代作用和斜长石的分离结晶作用的影响(汪晶等,2014)。
5. 讨论
5.1 成岩时代
野外出露特征显示闪长玢岩脉晚期侵入至花岗斑岩体中,因此其形成时代应该略晚于或晚于该花岗斑岩结晶年代。曹正琦(2016)通过锆石U–Pb定年测试获得研究区花岗斑岩的侵位年龄为(130.8±1.8)Ma,本研究中的闪长玢岩岩浆结晶年龄应晚于花岗斑岩侵位年龄。范裕等(2010)在宁芜盆地中利用LA–ICP–MS同位素定年方法获得闪长玢岩中同位素锆石U–Pb年龄为(130.2±2.0)Ma。黄丹峰等(2010)在大别山北缘利用SHRIMP同位素定年方法得到闪长玢岩中同位素锆石U–Pb年龄为(129.1±2.2)Ma。综上所述,西大别大悟地区闪长玢岩的形成很可能约为130 Ma。
5.2 脉岩成因
闪长玢岩的岩石地球化学烧失量为3.62%~7.83%,表明样品遭受一定程度蚀变。Nb、Ti、Zr等不相容元素具有活动性小,对岩石风化、交代和蚀变等作用过程反应不灵敏,利用与其他元素的图解,讨论相关元素的活动特点(Gibson et al.,1982),可以为岩石源区地幔性质和成分提供信息。
脉岩是母岩浆的代表,能有效反映源区物质组成(Westerman et al.,2003),闪长玢岩脉具有较低SiO2含量(49.97%~55.01%)、MgO含量(4.63%~5.49%),较高Al2O3含量(14.01%~14.65%)、 FeO*含量(1.63%~7.45%),壳源混染会使岩浆中SiO2含量明显增高、降低MgO值,但脉岩的SiO2−MgO不相关,说明壳源混染对脉岩影响不大。其次脉岩中微量元素、稀土元素含量变化不大,表明脉岩的岩浆在上升时没有受到壳源混染作用的干扰。轻稀土富集,轻、重稀土分异的程度较大,整体表现为较陡右倾型,(La/Yb)N值为21.21~43.34,δEu值为0.84~0.93,负异常不明显,表明在岩浆源区没有残留斜长石,而存在石榴子石和金红石残留,说明脉岩的岩浆来自深度较大(俞胜等,2022)。 Mg#值为60.17~90.19,大于下地壳的熔融产物Mg#值<40(Rapp et al.,1995); Nb/Ta值为13.06~18.47,大于地壳平均值(11.4)(Rudnik et al.,2003),接近于地幔值(17. 5±2) (Hofmann,1988;Green,1995);Zr/Hf值为40.09~44.05,接近于地幔值(36.7),样品投点均接近于Zr–Y图解的富集地幔区域(图4),表明脉岩的岩浆源区可能来自于富集地幔,与安徽庐枞盆地闪长玢岩的Sr–Nd–Pb同位素特征反映富集地幔岩浆源区的认识较为一致(汪晶等,2014)。
图 4 闪长玢岩Zr−Y判别图解(据Maitre et al.,1989)Figure 4. Zr−Y discrimination diagram of diorite porphyrite从三叠纪开始,扬子板块俯冲碰撞华北板块后,区域岩石圈地幔成分变化较大,早白垩世时期,中国东部岩石圈拉张构造事件对大别造山带产生影响,大量镁铁–超镁铁质岩体侵位至西大别地区,其同位素显示出富集特征(εNd(t)<−12),Zr−Y判别图解显示闪长玢岩样品均靠近富集地幔(图4)。以上特征表明区域岩浆源区为富集地幔(王世明等,2010)。
微量元素蛛网图分配型式的变化趋势表现为整体相近,亏损不相容元素Nb、Ta、Hf、Ti;富集亲石元素Sr,其中不相容元素Nb、Ta的亏损是由板块俯冲时岩浆喷发造成(Gill,1981),脉岩Nb异常值范围0.16~0.25,Nb的负异常特征通常被认为是俯冲带上火山岩或者陆壳岩石的明显特征(Jahn et al.,1999),微量元素特征可能是与俯冲板片作用相关的岩石圈地幔部分熔融有关(Pearce et al.,1995;彭松柏等,2016),与庐枞盆地中受古板块俯冲交代作用影响而形成的火山岩类似(袁峰等,2008),岩石中Sr含量为625.32×10−6~1112.55×10−6,明显高于地幔值(17.8×10−6)(Taylor et al.,1985),暗示脉岩的岩浆源区受到了俯冲板片流体交代作用的影响,使Sr含量增高(McCulloch et al.,1991),深俯冲大陆岩石圈可能在上地幔顶部滞留几十甚至上百个百万年之后,才形成熔融岩浆(赵子福等,2004)。从闪长玢岩的野外空间分布形态(图2a、图2b),间接反映了地区断裂构造结构面力学性质和断裂结构特征,大致可以辨别该脉岩充填的裂隙具剪张性,符合镁铁质岩浆贯入长英质岩浆结晶度及流变学特征的4个阶段混合模式,第一阶段为长英质岩浆结晶;第二阶段为花岗质岩浆近处于固态,在应力作用下产生岩石裂隙;第三阶段为具流变特征的基性岩浆注入到已经形成的花岗岩石裂隙,并在局部与其发生化学反应,形成具两者特性的复合岩墙,闪长玢岩呈角砾或锯齿状斑块产出;第四阶段为花岗质岩石已经固结,同时较为连续的基性岩墙(Fernandez et al.,1991)。区域深部的岩浆源区可能存在镁铁质和花岗质2种类型岩浆,前者可能稍晚侵位至后者,两者进一步进行混合作用。
综上所述,闪长玢岩脉的地球化学特征综合显示其岩浆来源于富集地幔,但俯冲而来的板片流体与其发生交代作用,使基性脉岩兼具俯冲作用的地球化学特征,该脉岩的岩浆源区可能受到了富集地幔与俯冲板片流体交代作用的影响,花岗斑岩、闪长玢岩为造山后伸展−拉张环境下形成的脉岩组合 。
5.3 构造环境
脉岩是研究深部岩石圈动力演化过程的重要“探针”(Poland et al.,2004),脉岩一般认为是岩浆在区域性地壳在拉张作用下而形成,对研究区域构造演化具有十分重要的意义(Halls,1982),闪长玢岩脉岩地球化学特征为中基性岩,TiO2–K2O–P2O5判别图解显示样品均落于大陆玄武岩区(图5a),TiO2–Zr(P2O5×10000)图解显示脉岩样品属于拉斑玄武岩系列(图5b),与庐枞盆地的样品均为板内玄武岩(图5c),Th/Nb值为0.48~0.60,Nb/Zr值为0.05~0.08,符合大陆拉张带玄武岩特征(0.27<Th/Nb<0.67,Nb/Zr>0.04)(孙书勤等,2003);且脉岩样品均落于Th/Hf−Ta/Hf图解的大陆拉张带玄武岩区(图5d)。
图 5 TiO2−K2O−P2O5判别图解(a)(Pearce,1975); TiO2−Zr(P2O5×10000)判别图解(b)(Winchester et al.,1976);Ti−Zr判别图解(c)(Pearce et al.,1973);Th/Hf−Ta/Hf判别图解(d)(据汪云亮等,2001)Ⅰ.板块发散边缘区(N−MORB);Ⅱ1.大洋岛弧玄武岩;Ⅱ2.陆缘岛弧及陆缘火山弧玄武岩;Ⅲ.大洋板内洋岛、海山玄武岩区及T−MORB、E−MORB区;Ⅳ1.陆内裂谷及陆缘裂谷拉斑玄武岩区;Ⅳ2.陆内裂谷碱性玄武岩区;Ⅳ3.大陆拉张带(或初始裂谷)玄武岩区;Ⅴ.地幔热柱玄武岩区Figure 5. (a) Discriminant diagram of TiO2−K2O−P2O5, (b) Discriminant diagram of TiO2−Zr (P2O5×10000),(c) Ti−Zr discriminant diagram, and (d) Th/ Hf−Ta/Hf discrimination diagram大别地区位于华北板块与扬子板块之间,是苏鲁−大别超高压变质带的重要组成部分,经历了洋−陆碰撞、陆−陆碰撞等构造演化过程。前人研究显示,大别地区的高压与超高压榴辉岩相反映了扬子地块陆壳向北俯冲至华北陆块之下, 240~220 Ma是其变质作用发生的重要时期,即大别造山带形成时间 (Li et al. ,1993; Hacker et al.,1998 ;李曙光等,2005;刘福来等,2006);碰撞造山导致地壳增厚(Leech et al. ,2001),随后出现应力松弛,区域应力状态从挤压转换到伸展,由伸展作用所引起的花岗岩侵位,通常会稍晚于区域地壳部分熔融,所以加厚地壳部分熔融作用发生时间通常被当作区域构造体制开始转换时间的最低值(David et al.,2001 ;Whitney et al.,2003)。马昌前等(2003)通过研究大别地区镁铁质岩石侵位年代学和花岗岩侵位年代学以及分别分析其岩石地化综合特征,认为135 Ma是区域地壳构造体制的转换时间。吴元保等(2001)以北大别地区岩石发生混合岩化时的年代学证据为依据,分析认为(137±4)Ma是大别地区从挤压向伸展发生转换的时间;并提出早白垩世大别造山带发生伸展垮塌,发生大量中酸性花岗岩侵位。吴开彬等(2013)通过对比西大别石鼓尖岩体、天堂寨岩体、薄刀峰岩体的Sr同位素比值及结晶年龄,将其分为三期,第一期石鼓尖岩体具同构造侵位变形特征,反映了挤压环境;第二期天堂寨岩体,变形发育在接触带和剪切带内,暗示着大别造山带的伸展垮塌;第三期薄刀尖岩体无变质变形,被认为是形成于大别造山带垮塌之后,反映了伸展环境。根据笔者对岩石地球化学特征研究及野外地质特征,认为大悟地区闪长玢岩为板内拉斑玄武岩系列,反映了大陆拉张构造环境,结合闪长玢岩脉侵位时代为早白垩世。因此,大悟地区早白垩世闪长玢岩形成于造山后大陆拉张环境,与前人认为大别造山带伸展时期较为一致(吴开彬等,2013)。
6. 结论
(1)岩石地球化学特征显示,闪长玢岩属于中基性岩,为大陆拉斑玄武岩系列;稀土元素有较高的总量,稀土配分模式显示强烈富集轻稀土的右倾型,亏损不相容元素Nb、Ta、Hf、Ti;大离子亲石元素Sr富集。
(2)研究区闪长玢岩脉的岩浆源区可能受到了俯冲板片流体交代作用的影响,地球化学特征综合显示其可能来源于富集地幔;
(3)脉岩野外地质特征及前人研究资料表明,闪长玢岩侵位于早白垩世,为大别造山后伸展−拉张环境下形成的脉岩。
致谢:衷心感谢中国地质调查局西安地质调查中心陈隽璐正高级工程师对论文写作的指导!
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图 1 研究区地质简图(a据Xu et al. ,2012修改)
Figure 1. Geological map of research area
图 5 乌孙山地区花岗岩和闪长岩TAS图解(a),K2O-SiO2(b)和A/NK-A/CNK(c)图解(引自Bao et al., 2018)
Figure 5. (a) The TAS, (b) K2O-SiO2 and (c) A/NK-A/CNK diagram of granite and diorite in Wusunshan area
图 6 乌孙山地区花岗岩、闪长岩及中酸性火山岩稀土元素球粒陨石标准配分曲线和微量元素原始地幔标准化蛛网图(标准化值、N-MORB数据引自 Sun et al.,1989;上地壳、下地壳数据引自Rudnick et al.,2003)
Figure 6. Chondrite-normalized REE patterns and primitive mantle-normalized spidergrams of granites and diorite from the Wusunshan area
图 7 (Na2O+K2O)/CaO-Zr+Nb+Ce+Y图解(Whalen et al., 1987)及Rb-Ce和Rb-Y图解(Wang et al., 2012)
Figure 7. (Na2O+K2O)/CaO-Zr+Nb+Ce+Y diagrams and Rb-Ce、Rb-Y diagrams
表 1 乌孙山地区花岗岩LA-ICP-MS锆石U-Pb定年结果
Table 1 LA-ICP-MS zircon U-Pb date of the granite in Wusunshan area
样品号 含量(10−6) 同位素比值 同位素比值 年龄(Ma) 13XY-34 Pb U 206Pb/238U 1σ 207Pb/235U 1σ 207Pb/206Pb 1σ 208Pb/232Th 1σ 232Th/238U 1σ 206Pb/238U 1σ 207Pb/235U 1σ 207Pb/206Pb 1σ 1 17 198 0.0766 0.0006 0.5975 0.0376 0.0565 0.0036 0.0224 0.0012 0.7349 0.0022 476 4 476 30 474 142 3 10 165 0.0582 0.0004 0.4400 0.0279 0.0548 0.0035 0.0125 0.0006 0.6879 0.0022 365 2 370 23 404 142 4 18 241 0.0688 0.0005 0.5290 0.0218 0.0558 0.0024 0.0151 0.0006 0.7741 0.0010 429 3 431 18 445 95 5 14 227 0.0587 0.0004 0.4420 0.0176 0.0546 0.0021 0.0121 0.0005 0.6571 0.0007 368 2 372 15 397 88 6 15 264 0.0570 0.0003 0.4265 0.0160 0.0543 0.0020 0.0108 0.0005 0.6880 0.0010 357 2 361 13 383 83 7 14 228 0.0584 0.0004 0.4401 0.0195 0.0546 0.0024 0.0121 0.0006 0.6391 0.0012 366 2 370 16 397 98 8 21 347 0.0581 0.0004 0.4353 0.0147 0.0543 0.0018 0.0111 0.0006 0.8042 0.0009 364 2 367 12 384 74 9 20 327 0.0579 0.0004 0.4373 0.0160 0.0548 0.0020 0.0104 0.0005 0.7997 0.0095 363 2 368 13 403 81 10 18 289 0.0586 0.0003 0.4391 0.0168 0.0544 0.0020 0.0120 0.0006 0.7757 0.0006 367 2 370 14 386 84 11 14 244 0.0576 0.0004 0.4323 0.0281 0.0545 0.0035 0.0117 0.0005 0.6680 0.0027 361 3 365 24 390 144 12 11 178 0.0586 0.0004 0.4358 0.0288 0.0539 0.0035 0.0116 0.0005 0.7017 0.0013 367 2 367 24 367 147 13 18 292 0.0580 0.0004 0.4323 0.0217 0.0540 0.0027 0.0130 0.0005 0.7243 0.0012 364 2 365 18 372 113 14 19 326 0.0574 0.0003 0.4322 0.0190 0.0546 0.0024 0.0098 0.0004 0.8631 0.0009 360 2 365 16 398 98 15 8 138 0.0569 0.0005 0.4284 0.0480 0.0546 0.0061 0.0165 0.0010 0.5464 0.0010 357 3 362 41 395 250 21 20 338 0.0579 0.0003 0.4364 0.0129 0.0546 0.0016 0.0138 0.0007 0.6215 0.0015 363 2 368 11 397 64 22 22 369 0.0572 0.0003 0.4296 0.0184 0.0544 0.0023 0.0120 0.0007 0.7433 0.0029 359 2 363 16 390 95 23 26 423 0.0579 0.0003 0.4368 0.0136 0.0547 0.0017 0.0131 0.0008 0.6679 0.0024 363 2 368 11 400 69 24 19 322 0.0580 0.0003 0.4351 0.0163 0.0544 0.0020 0.0124 0.0009 0.6336 0.0010 364 2 367 14 388 82 26 22 353 0.0575 0.0003 0.4293 0.0158 0.0542 0.0020 0.0125 0.0007 0.7908 0.0013 360 2 363 13 379 81 27 20 344 0.0563 0.0004 0.4205 0.0354 0.0541 0.0046 0.0125 0.0007 0.7217 0.0038 353 2 356 30 377 189 28 20 339 0.0568 0.0004 0.4230 0.0239 0.0540 0.0029 0.0121 0.0007 0.7839 0.0016 356 2 358 20 370 123 29 21 349 0.0567 0.0003 0.4238 0.0142 0.0542 0.0018 0.0141 0.0009 0.6705 0.0013 356 2 359 12 379 74 30 29 468 0.0578 0.0003 0.4356 0.0141 0.0547 0.0017 0.0130 0.0009 0.7430 0.0009 362 2 367 12 399 71 表 2 乌孙山地区花岗岩和闪长岩主量元素(%)、稀土元素和微量元素(10−6)分析结果
Table 2 Major and trace element analyses of the granites and dioritefrom the Wusunshan area
样品 二长花岗岩:13XY-34 闪长岩:13XY-35 1h 2h 3h 4h 5h 1h 2h 3h 4h 5h 6h SiO2 71.18 70.22 70.78 72.00 71.35 52.07 52.61 52.24 52.54 51.84 52.32 Al2O3 14.04 14.40 14.18 14.29 14.22 16.50 16.78 16.70 16.83 16.68 16.86 Fe2O3 0.60 0.88 0.62 0.20 0.88 2.46 2.37 2.30 1.91 1.83 2.27 FeO 1.90 2.12 2.01 1.81 1.65 5.78 6.26 6.40 6.71 6.66 6.36 FeOT 2.44 2.91 2.57 1.99 2.44 7.99 8.39 8.47 8.43 8.31 8.40 CaO 1.84 2.64 2.16 1.86 2.50 8.23 8.30 8.01 8.26 7.48 8.27 MgO 0.96 1.00 0.88 0.67 0.83 5.90 5.79 6.00 6.04 5.36 6.04 K2O 3.90 3.94 3.86 4.33 3.90 1.86 1.96 1.86 1.68 1.72 1.71 Na2O 3.63 3.43 3.72 3.63 3.50 3.42 2.50 2.80 2.57 3.46 2.68 TiO2 0.31 0.35 0.31 0.25 0.29 0.82 0.82 0.82 0.79 0.87 0.80 P2O5 0.07 0.09 0.07 0.05 0.07 0.18 0.15 0.15 0.15 0.16 0.15 MnO 0.04 0.05 0.05 0.04 0.04 0.17 0.15 0.16 0.15 0.15 0.15 LOI 1.51 0.88 1.35 0.87 0.76 2.58 2.28 2.51 2.36 3.75 2.35 Total 99.98 100.00 99.99 100.00 99.99 99.97 99.97 99.95 99.99 99.96 99.96 A/CNK 1.04 0.98 1.00 1.02 0.98 0.73 0.79 0.79 0.80 0.79 0.79 K2O/Na2O 1.07 1.15 1.04 1.19 1.11 0.54 0.78 0.66 0.65 0.50 0.64 Mg# 41.22 37.96 37.91 37.50 37.72 56.81 55.14 55.80 56.08 53.49 56.16 σ 2.01 2.00 2.07 2.18 1.93 3.07 2.07 2.35 1.89 3.04 2.07 C 0.68 0.13 0.37 Cu 6.99 4.57 6.09 4.27 4.20 25.50 76.00 72.00 75.30 88.00 69.40 Pb 4.42 5.72 5.29 6.60 7.15 13.00 6.12 6.52 15.20 44.00 15.30 Zn 18.20 17.70 18.40 13.90 14.60 80.10 64.80 66.00 75.30 92.50 71.60 Cr 5.44 4.27 14.80 4.52 3.47 137.00 103.00 104.00 109.00 94.00 109.00 Ni 1.86 2.15 6.75 1.62 1.21 33.10 24.70 24.40 27.20 20.20 26.00 Co 6.03 6.29 5.52 4.12 4.94 29.00 31.80 33.60 33.10 31.40 32.40 Li 1.99 1.81 0.92 1.00 1.19 6.66 6.38 9.24 9.05 11.70 9.10 Rb 113.00 129.00 102.00 119.00 118.00 65.30 61.10 64.80 56.50 56.40 56.90 Cs 1.30 1.56 1.39 1.14 1.43 0.79 2.04 1.56 1.00 0.92 0.92 Mo 0.46 0.22 0.56 0.21 0.22 0.41 0.28 0.21 0.13 0.36 0.21 Sr 204.00 246.00 241.00 204.00 230.00 492.00 413.00 465.00 417.00 382.00 413.00 Ba 711.00 626.00 708.00 500.00 668.00 275.00 355.00 356.00 327.00 326.00 316.00 V 49.00 57.80 47.30 32.40 45.20 266.00 285.00 290.00 284.00 306.00 286.00 Sc 6.92 8.19 7.01 4.82 6.70 28.10 33.30 30.40 29.20 33.30 33.90 Nb 5.79 6.51 6.04 4.97 6.15 3.35 3.34 1.52 1.51 2.27 1.45 Ta 0.61 0.62 0.59 0.73 0.73 0.40 0.35 0.20 0.18 0.26 0.17 Zr 144.00 165.00 144.00 114.00 159.00 45.90 42.70 41.20 43.00 49.00 35.90 Hf 3.22 3.87 3.19 2.78 3.69 1.30 1.35 0.98 0.93 1.36 0.82 Ga 13.00 14.40 13.40 13.10 13.60 16.00 16.40 15.80 15.80 17.00 15.70 U 1.82 1.64 1.46 1.69 1.69 0.88 0.76 0.51 0.43 0.52 0.38 Th 11.00 9.39 10.10 10.80 10.70 4.10 4.31 1.91 1.56 1.75 1.34 Y 13.90 15.80 14.40 12.20 14.60 12.50 17.00 11.40 11.20 13.90 11.00 Ti 1858.14 2097.90 1858.14 1498.50 1738.26 4915.08 4915.08 4915.08 4735.26 5214.78 4795.20 K 32375.07 32707.12 32043.02 35944.63 32375.07 15440.42 16270.55 15440.42 13946.18 14278.24 14195.22 P 305.20 392.40 305.20 218.00 305.20 784.80 654.00 654.00 654.00 697.60 654.00 La 17.50 16.70 15.20 17.70 18.70 9.77 9.45 5.10 5.17 7.79 4.94 Ce 34.20 32.50 31.50 31.50 36.50 20.50 22.10 11.30 11.90 17.50 11.30 Pr 3.88 3.64 3.52 3.37 3.90 2.34 2.83 1.59 1.60 2.28 1.54 Nd 12.60 12.50 12.10 10.10 12.90 8.83 10.80 6.82 6.97 9.11 6.43 Sm 2.75 2.56 2.40 2.16 2.58 2.15 2.89 1.87 1.91 2.24 1.81 Eu 0.69 0.63 0.67 0.56 0.63 0.84 0.86 0.78 0.76 0.95 0.75 Gd 2.50 2.67 2.48 1.98 2.42 2.28 2.96 2.08 2.07 2.46 2.12 Tb 0.41 0.45 0.41 0.31 0.41 0.40 0.48 0.34 0.35 0.42 0.36 Dy 2.54 2.72 2.46 1.96 2.59 2.31 3.03 2.14 2.09 2.52 2.06 Ho 0.56 0.59 0.53 0.44 0.54 0.47 0.65 0.44 0.44 0.52 0.44 Er 1.62 1.74 1.54 1.31 1.58 1.35 1.88 1.26 1.20 1.51 1.25 Tm 0.26 0.27 0.25 0.21 0.25 0.20 0.29 0.18 0.18 0.23 0.18 Yb 1.67 1.81 1.65 1.45 1.69 1.32 1.82 1.17 1.20 1.42 1.12 Lu 0.26 0.29 0.26 0.23 0.27 0.21 0.28 0.18 0.18 0.22 0.17 ∑REE 81.44 79.07 74.97 73.28 84.96 52.97 60.32 35.25 36.02 49.17 34.47 (La/Yb)N 7.52 6.62 6.61 8.76 7.94 5.31 3.72 3.13 3.09 3.94 3.16 (La/Sm)N 4.11 4.21 4.09 5.29 4.68 2.93 2.11 1.76 1.75 2.25 1.76 (Gd/Yb)N 1.24 1.22 1.24 1.13 1.18 1.43 1.35 1.47 1.43 1.43 1.57 Sr/Y 14.68 15.57 16.74 16.72 15.75 39.36 24.29 40.79 37.23 27.48 37.55 δEu 0.80 0.74 0.84 0.83 0.77 1.16 0.90 1.21 1.17 1.24 1.17 -
高俊, 钱青, 龙灵利, 等. 西天山的增生造山过程[J]. 地质通报, 2009, 28(12): 1804−1816. GAO Jun, QIAN Qing, LONG Lingli, et al. Accretionary orogenic process of Western Tianshan, China[J]. Geologcal Bulletin of China,2009,28(12):1804−1816.
李永军, 李注苍, 佟丽莉, 等. 论天山古洋盆关闭的地质时限-来自伊宁地块石炭系的新证据[J]. 岩石学报, 2010, 25(6): 2905−2912. LI Yongjun, LI Zhucang, TONG Lili, et al. Revisit the constraints on the closure of the Tianshan ancient oceanic basin: New evidence from Yining block of the Carboniferous[J]. Acta Petrologica Sinica,2010,25(6):2905−2912.
李承东, 张旗, 苗来成, 等. 冀北中生代高Sr低Y和低Sr低Y型花岗岩: 地球化学、成因及其与成矿作用的关系[J]. 岩石学报, 2004, 20(2): 269−284. LI Chengdong, ZHANG Qi, MIAO Laicheng, et al. Mesozoic high-Sr, low-Y and low-Sr, low-Y types granitoids in the northern Hebei province: Geochemistry and petrogenesis and its relation to mineralization of gold deposits[J]. Acta Petrologica Sinica,2004,20(2):269−284.
李昌年. 岩浆混合作用及其研究评述[J]. 地质科技情报, 2002, 21(4): 49−54. LI Changnian. Comment on the magama mixing and their research[J]. Geological Science and Technology Information,2002,21(4):49−54.
刘新, 钱青, 苏文, 等. 西天山阿吾拉勒西段木汗巴斯陶侵入岩体的地球化学特征、时代及地质意义[J]. 岩石学报, 2012, 28(8): 2401−2413. LIU Xin, QIAN Qing, SU Wen, et al. Pluton from Muhanbasitao in the western of Awulale, Western Tianshan: Geochemistry, geochronology and geological implications[J]. Acta Petrologica Sinica,2012,28(8):2401−2413.
马昌前, 王人镜. 花岗质岩浆起源和多次岩浆混合的标志: 包体-以北京周口店岩体为例[J]. 地质论评, 1992, 38(2): 109−119. MA Changqian,WANG Renjing. Enclaves as indicators of the origin of granitoid magama and repeater magama mingling : an example fromthe Zhoukoudian intrusionBeijing[J]. Geological Review,1992,38(2):109−119.
齐有强, 胡瑞忠, 刘桑, 等. 岩浆混合作用研究综述[J]. 矿物岩石地球化学通报, 2008, 27(4): 409−416. QI Youqiang ,HU Ruizhong ,LIU Shen,et al. Review on Magana Mixing and Mingling[J]. Bulletin of Mineralogy, Petrology and Geochemistry, 2008 , 27(4):409−416.
茹艳娇. 西天山大哈拉军山组火山岩地层序列、 岩石成因与构造环境[D]. 西安: 长安大学, 2012, 1−113. RU Yanjiao. The Stratigraphic Sequanence,Petrogenesis and Tectonic Setting of the Volcanic Rocks of the Dahalajunshan Formation,Western Tianshan Mountain,China[D]. Xi’an: Chang’an University,2012, 1−113.
舒良树, 王博, 朱文斌. 南天山蛇绿混杂岩中放射虫化石的时代及其构造意义[J]. 地质学报, 2007, 81(9): 1161−1168. SHU Liangshu,WANG Bo,ZHU Wenbin. Age of Radiolarian Fossils from the Heiyingshan Ophiolitic Melange,Southerm Tianshan Belt,NWChina ,and its Tectonic Significance[J]. Acta Geologica Sinica,2007,81(9):1161−1168.
孙吉明, 白建科, 马中平, 等. 西天山特克斯县北乌孙山大哈拉军山组火山岩地球化学特征及构造意义[J]. 岩石矿物学杂志, 2014, 33(5): 799−810. SUN Jiming, BAI Jianke, MA Zhongping, et al. Geochemical characteristics and tectonic implications of Wusunshan volcanic rocks in northern Tekes County of West Tianshan Mountains[J]. Acta Petrologica et Mineralogica,2014,33(5):799−810.
唐功建, 陈海红, 王强, 等. 西天山达巴特A型花岗岩的形成时代与构造背景[J]. 岩石学报, 2008, 24(5): 947−958 TANG Gongjian, CHEN Haihong, WANG Qiang, et al. Geochronological age and tectonic background of the Dabate A-type granite pluton in the west Tianshan[J]. Acta Petrologica Sinica. 2008, 24(5): 947−958.
童英, 王涛, 洪大卫, 等. 北疆及邻区石炭-二叠纪花岗岩时空分布特征及其构造意义[J]. 岩石矿物学杂志, 2010, 29(6): 619−641. TONG Ying, WANG Tao, HONG Dawei, et al. Spatial and temporal distribution of the Carboniferous-Permian granitoids in northern Xinjiang and its adjacent areas, and its tectonic significance[J]. Acta Petrologica et Mineralogica,2010,29(6):619−641.
王博, 舒良树, Cluzel D, 等. 伊犁北部博罗科努岩体年代学和地球化学研究及其大地构造意义[J]. 岩石学报, 2007, 23(8): 1885−1900. WANG Bo, SHU Liangshu, Cluzel D, et al. Geochronological and geochemical studies on the Borohoro plutons, north of Yili, NW Tianshan and their Tectonic implication[J]. Acta Petrologica Sinica,2007,23(8):1885−1900.
吴福元, 李献华, 杨进辉, 等. 花岗岩成因研究的若干问题[J]. 岩石学报, 2007, 23(6): 1217-1238. WU Fuyuan, LI Xianhua, YANG Jinhui, et al, Discussions on the petrogenesis of granites[J]. Acta Petrologica Sinica, 2007, 23(6): 1217-1238.
许继峰, 邬建斌, 王强, 等. 埃达克岩与埃达克质岩在中国的研究进展[J]. 矿物岩石地球化学通报, 2014, 33(1): 6−13. XU Jifeng, WU Jianbin, WANG Qiang, et al. Research Advances of Adakites and Adakitic Rocks in China[J]. Bulletin of Mineralogy Petrology and Geochemistry,2014,33(1):6−13.
张旗, 王焰, 李承东, 等. 花岗岩的Sr-Yb分类及其地质意义[J]. 岩石学报, 2006, 22(9): 2249−2269. ZHANG Qi, WANG Yan, LI Chengdong, et al. Granite classification on the basis of Sr and Yb contents and its implications[J]. Acta Petrologica Sinica,2006,22(9):2249−2269.
朱永峰, 周晶, 宋彪, 等. 新疆“大哈拉军山组”火山岩的形成时代问题及其解体方案[J]. 中国地质, 2006, 33(3): 487−497. ZHU Yongfeng, ZHOU Jing, SONG Biao, et al. Age of the "Dahalajunshan" Formation in Xinjiang and its disintegration[J]. Chinese Geology,2006,33(3):487−497.
Barbarin B. A review of the relationships between granitoid types, their origins and their geodynamic environments[J]. Lithos,1999,46(3):605−626. doi: 10.1016/S0024-4937(98)00085-1
Bao Z H, Cai K D, Sun M, et al. Continental crust melting induced by subduction initiation of the South Tianshan Ocean: Insight from the Latest Devonian granitic magmatism in the southern Yili Block, NW China[J]. Journal of Asian Earth Sciences,2018,153:100−117. doi: 10.1016/j.jseaes.2017.04.026
Dong Y P, Zhang G W, Neubauer F, et al. Syn- and post-collisional granitoids in the Central Tianshan orogen: Geochemistry, geochronology and implications for tectonic evolution[J]. Gondwana Research,2011,20(2−3):568−581.
Gao J, Li M S, Xiao X X, et al. Paleozoic tectonic evolution off the Tianshan Orogen, northwestern China[J]. Tectonophysics,1998,287(1−4):213−231. doi: 10.1016/S0040-1951(97)00211-4
Gao J, Klemd. Formation of HP-LT rocks and their tectonic implications in the western Tianshan Orogen, NW China: geochemical and age constraints[J]. Lithos,2003,66:1−22.
Gerya T V. Future directions in subduction modeling[J]. Journal of Geodynamics,2011,52(5):344−378.
Gerya T V, Connolly J A D, Yuen D A. Why is terrestrial subduction one-sided? [J]. Geology, 2008, 36 (1), 43−46.
Han B F, Guo Z J, Zhang Z C, et al. Age, geochemistry, and tectonic implications of a late Paleozoic stitching pluton in the North Tian Shan suture zone, western China[J]. Geological Society of America Bulletin,2010,122(3−4):627−640. doi: 10.1130/B26491.1
Huang H, Wang T, Tong Y, et al. Rejuvenation of ancient micro-continents during accretionary orogenesis: Insights from the Yili Block and adjacent regions of the SW Central Asian Orogenic Belt[J]. Earth-Science Reviews, 2020, 208: 1−22.
Hyndman R D, Currie C A. Subduction zone backarcs, continental mobile belts, and orogenic heat[J]. GSA Today , 2005, 15, 463−475.
Jiang Z S, Zhang Z H, Wang Z H, et al. Geology, geochemistry, and geochronology of the Zhibo iron deposit in the Western Tianshan, NW China: Constraints on metallogenesis and tectonic setting[J]. Ore Geology Reviews,2014,57(3):406−424.
Jung S, Pfänder J A. Source composition and melting temperatures of orogenic granitoid: Constraints from CaO/Na2O, Al2O3/TiO2 and accessory mineral saturation thermometry[J]. European Journal of Mineralogy,2007,19(6):859−870. doi: 10.1127/0935-1221/2007/0019-1774
Kröner A, Alexeiev D V, Rojas-Agramonte Y, et al. Mesoproterozoic ( Grenville-age) terranes in the Kyrgyz North Tianshan: Zircon ages and Nd-Hf isotopic constraints on the origin and evolution of basement blocks in the southern Central Asian Orogen[J]. Gondwana Research,2013,23(1):272−295.
Long L L, Gao J, Klemd R, et al. Geochemical and geochronological studies of granitoid rocks from the Western Tianshan Orogen: Implications for continental growth in the southwestern Central Asian Orogenic Belt[J]. Lithos,2011,126(3-4):321−340. doi: 10.1016/j.lithos.2011.07.015
Liu W, Fei P X. Methane-rich fluid inclusions from ophiolitic dunite and post-collisional mafic-ultramafic intrusion: The mantle dynamics underneath the Paleo-Asian Ocean through to the post-collisional period[J]. Earth and Planetary Science Letters,2006,242(3−4):286−301. doi: 10.1016/j.jpgl.2005.11.059
Liu Y. Early Carboniferous Radiolarian Fauna from Heiyingshan South of the Tianshan Mountains and Its Geotectonic Significance[J]. Acta Petrologica Sinica,2001,75(1):101−105. doi: 10.1111/j.1755-6724.2001.tb00511.x
Li Y J, Sun L D, Wu H R, et al. Permo-Carboniferous Radiolarians from the Wupataerkan Group , Western South Tianshan , Xinjiang , China[J]. Acta Petrologica Sinica, 2005, 79(1): 16−23.
Ma X X, Shu L S, Meert J G. Early Permian slab breakoff in the Chinese Tianshan belt inferred from the postcollisional granitoids[J]. Gondwana Research,2015,27(1):228−243. doi: 10.1016/j.gr.2013.09.018
Pearce J A, Harris N B W, Tindle A G. Trace element discrimination diagrams for the tectonic interpretation of granitic rocks[J]. Journal of Petrology,1984,25(4):956−983. doi: 10.1093/petrology/25.4.956
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):251−286. doi: 10.1146/annurev.ea.23.050195.001343
Qian Q, Gao J, Klemd R, et al. Early Paleozoic tectonic evolution of the Chinese South Tianshan Orogen: constraints from SHRIMP zircon U-Pb geochronology and geochemistry of basaltic and diorite rocks from Xiate, NW China[J]. International Journal of Earth Sciences, 2008, 98(3): 551−569.
Rudnick, Gao S. Composition of the continental crust[J]. In: Rudnick R L (ed.). Treatise on Geochemistry[M]. Amsterdam: Elsevier,2003,3:1−64.
Seltmann R, Konopelko D, Biske G, et al. Hercynian post-collisional magmatism in the context of Paleozoic magmatic evolution of the Tien Shan orogenic belt[J]. Journal of Asian Earth Sciences,2011,42(42):821−838.
Sun S S, McDonough W F. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In: Saunders, A. D, Norry, M. J (Eds.). Magmatism in Ocean Basins[J]. In: Saunders A D, Norry M J (Eds.). Magmatism in Ocean Basins[M]. Geological Society of London Special Publication,1989,42:313−345. doi: 10.1144/GSL.SP.1989.042.01.19
Sun L H, Wang YJ , Fan W M, et al. Post collisional potassic magmatism in the Southern Awulale Mountain, western Tianshan Orogen: Petrogenetic and tectonic implications[J]. Gondwana Research,2008,14(3):383−394.
Su W, Gao J, Klemd R, et al. U-Pb zircon geochronology of Tianshan eclogites in NW China: implication for the collision between the Yili and Tarim blocks of the southwestern Altaids[J]. European Journal of Mineralogy,2010,22:473−478.
Whalen J B, Currie K L, Chappell B W. A-type granites: geochemical characteristics, discrimination and petrogenesis[J]. Contributions to Mineralogy and Petrology,1987,95:407−419. doi: 10.1007/BF00402202
Windley B F, Alexeiev D, Xiao W J, et al. Tectonic models for accretion of the Central Asian Orogenic Belt[J]. Journal of the Geological Society,2007,164(12):31−47.
Wilhem C, Windley B. F, Stampfli G. M. The Altaids of Central Asia: a tectonic and evolutionary innovative review[J]. Earth Science Reviews,2012,113:303−341. doi: 10.1016/j.earscirev.2012.04.001
Wyllie P J , Cox K G, Biggar C M. The Habit of Apatite in Synthetic Systems and Igneous Rocks[J]. Journal of Petrology, 1962, 3 (2).
Wang M, Zhang J J, Zhang B, et al. An Early Paleozoic collisional event along the northern margin of the Central Tianshan Block: Constraints from geochemistry and geochronology of granitic rocks[J]. Journal of Asian Earth Sciences,2014,113:325−338.
Wang Q, Zhu D C, Zhao Z D, et al. Magmatic zircons from I-, S- and A-type granitoids in Tibet: trace element characteristics and their application to detrital zircon provenance study[J]. Journal of Asian Earth Sciences,2012,53:59−66.
Xia L Q, Xu X Y, Li X M, et al. Reassessment of petrogenesis of Carboniferous-Early Permian rift-related volcanic rocks in the Chinese Tianshan and its neighboring areas[J]. Geoscience Frontiers,2012,3(4):445−471. doi: 10.1016/j.gsf.2011.12.011
Xiao W J, Kusky T, Safonova I, et al. Tectonics of the Central Asian Orogenic Belt and its Pacific analogues[J]. Journal of Asian Earth Sciences,2015,113:1−6. doi: 10.1016/j.jseaes.2015.06.032
Xiao W J, Santosh M. The western Central Asian Orogenic Belt: A window to accretionary orogenesis and continental growth[J]. Gondwana Research,2014,25(4):1429−1444. doi: 10.1016/j.gr.2014.01.008
Xiao W J, Zhang L C, Qin K Z, et al. Paleozoic accretionary and collisional tectonics of the eastern Tianshan (China): Implications for the continental growth of central Asia[J]. American Journal of Science,2004,304(4):370−395. doi: 10.2475/ajs.304.4.370
Xiao W J, Windley B. F, Allen M. B, et al. Paleozoic multiple accretionary and collisional tectonics of the Chinese Tianshan orogenic collage[J]. Gondwana Research,2013,23:1316−1341.
Zhang D Y, Zhang Z C, Encarnación J, et al. Petrogenesis of the Kekesai composite intrusion, western Tianshan, NW China: Implications for tectonic evolution during late Paleozoic time[J]. Lithos,2012,146(8):65−79.
Zhao Z H, Xiong X L, Wang Q, et al. Late Paleozoic under plating in North Xinjiang: Evidence from shoshonite and adakite[J]. Gongwana Research,2009,16:216−226. doi: 10.1016/j.gr.2009.03.001
Zhang L F, Du J X, Lü Z, et al. A huge oceanic-type uhp metamorphic belt in Southwestern Tianshan, China: peak metamorphic age and p-t path[J]. Science Bulletin,2013,58(35):4378−4383. doi: 10.1007/s11434-013-6074-x
Zhang L F, Ai Y L, Li X P , et al. Triassic collision of westernTianshan orogenic belt , China: Evidence from SHRIMP U-Pb datingof zircon from HP/UHP eclogitic rocks[J]. Lithos,2007,96(1−2):266−280.
Zhong L, Wang B, Alexeiev D V, et al. Paleozoic multi-stage accretionary evolution of the SW Chinese Tianshan: new constraints from plutonic complex in the Nalati Range[J].Gondwana Research, 2017, 45, 254−274.
Xu X Y, Wang H L, Li P, et al. Geochemistry and geochronology of Paleozoic intrusions in the Nalati (Narati) area in weatern Tianshan, Xinjiang, China: Implications for Paleozoic tectonic evolution[J]. Journal of Asian Earth Sciences, 2012, 1−30.
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