岩石学报  2016, Vol. 32 Issue (10): 2965-2980   PDF    
朝鲜半岛冠帽地块的基底属性:来自银德洞变质侵入杂岩的锆石U-Pb年代学和岩石地球化学证据
张晓晖1, 王浩铮1,2, 朴贤旭3, 杨正赫3, 金正男3     
1. 中国科学院地质与地球物理研究所, 岩石圈演化国家重点实验室, 北京 100029 ;
2. 中国科学院大学地球科学学院, 北京 100039 ;
3. 朝鲜国家科学院地质研究所, 平壤 3812100
摘要: 地体基底建造的甄别和表征是联结华北克拉通与朝鲜半岛早期演化历史的基本纽带。针对朝鲜半岛前寒武纪基底建造研究方面的薄弱环节,本文表征了冠帽地块清津地区银德洞出露的变质深成侵入杂岩。3个代表性样品的SIMS锆石U-Pb定年结果显示,早期中性片麻岩记录的岩浆侵入年龄为约2.53Ga,晚期钾长花岗质片麻岩记录的岩浆侵入年龄为约2.51Ga,表明银德洞变质杂岩形成于新太古代晚期。参考变质杂岩的岩石地球化学特征,其原岩组成可能包括石英闪长岩和钾长花岗岩,大体上可与全球典型的岩浆型紫苏花岗岩系列相类比。结合3个样品变化较大的锆石εHft)值(-1.7~+10.5),我们推测银德洞变质侵入杂岩可能形成于玄武质下地壳岩石的部分熔融及其后的结晶分异作用,代表了活动大陆边缘岩浆弧环境下的典型产物。银德洞变质杂岩归属于新太古代岩浆弧根部岩浆岩建造的研究认识,不仅为判定冠帽地块与华北克拉通东部的吉南和龙地块以及辽北清原地块之间的亲缘性提供了岩石学证据,而且暗示这些地块在新太古代共同处在一个类似于安第斯活动大陆边缘的构造环境。
关键词: 变质侵入杂岩     锆石U-Pb定年     岩石地球化学     新太古代     冠帽地块     朝鲜半岛    
Basement affinity of the Kwanmo Massif, Korean Peninsula:Evidence from zircon U-Pb geochronology and petro-geochemistry of the Undokdong meta-intrusive complex.
ZHANG XiaoHui1, WANG HaoZheng1,2, PARK HyoNuk3, YANG JongHyok3, KIM JongNam3     
1. State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China ;
2. College of Earth Science, University of Chinese Academy of Sciences, Beijing 100039, China ;
3. Institute of Geology, State Academy of Sciences, Pyongyang 3812100, DPRK
Abstract: Recognizing and characterizing the basement affinity of terranes presents a critical task for establishing the link between the Korean Peninsula (KP) and the North China Craton (NCC) since Archean on. This study aims to bridge the gap in the characterization of the Precambrian basement rocks in the KP by documenting the Undokdong meta-intrusive complex in the Chongjin region, the Kwanmo Massif. SIMS zircon U-Pb dating on three representative samples from the complex yielded magmatic crystallization ages from 2.53 to 2.51Ga. In terms of their petrological and geochemical traits, the protoliths of these metamorphic rocks can be recognized as quartz diorite and potassic granite, and compare well with the classic magmatic charnockite suites in the world. Synthesizing these features with the variable zircon εHf(t) values from -1.7 to+10.5 in the three samples, we infer that the Undokdong meta-intrusive complex might originate from the high-T and CO2-rich fluid-fluxed partial melting of basaltic lower crust and subsequent fractionation, thus representing typical products of magmatic arcs on an active continental margin. Given a possible tectonic link with a Neoarchean arc root, these rocks could present a spatial reference for defining the consistency in tectonic affinity between the Kwanmo Massif and the Helong/Qingyuan terrains in the eastern NCC, thus leading to the characterization of an Andean-type active continental margin across these terrains during Neoarchean.
Key words: Meta-intrusive complex     Zircon U-Pb dating     Petro-geochemistry     Neoarchean     the Kwanmo Massif     Korean Peninsula    
1 引言

地体基底建造的甄别和表征既是揭示地球早期古老克拉通形成演化的基础工作,又是基于区域对比重建早期超大陆构造格局的关键任务。作为中国面积最大和最古老的陆块,华北克拉通记录了复杂程度远超全球其他典型克拉通的前寒武纪演化历史(Zhai and Santosh,2011; Zhao et al.,20122016)。揆诸华北克拉通逐渐成为全球焦点研究区的近三十年研究历程,其与朝鲜半岛的关系一直是中外地质学家关注的核心主题之一(图 1a)。虽然'中朝克拉通’的称谓直观地表达了朝鲜半岛与华北克拉通自太古宙以来在地质演化上的密切联系(张文佑,1986; Lee,1987; Paek et al.,1996; Lee et al.,2000; Oh and Kusky,2007; Rogers and Santosh,2006; Zhai et al.,2007a; Niu et al.,2015),但精细刻画这种关联决非一蹴而就之事。得益于高精度测年手段的大量运用,近年来中外学者在朝鲜半岛前寒武纪基底建造甄别和表征方面取得重要进展。一方面,在京畿地块和岭南地块识别出了太古宙地壳残片(Cho et al.,2008)并建立了古元古代岩浆-变质事件的精细序列(Lee et al.,200020052014; Kim and Cho,2003; Zhai et al.,2005; Oh et al.,2006; Horie et al.,2009; Kim et al.,200820122014; Yengkhom et al.,2014)。另一方面,在前寒武纪基底岩系据称出露最广泛的北部狼林地块(Paek et al.,1996; 曹林和朱东,1999),中国学者先后厘定了两期古元古代侵入岩(Zhao et al.,2006; Wu et al.,2007a; Zhai et al.,2007b)和新太古代片麻岩-斜长角闪岩系(Zhang et al.,2016)。这些朝鲜半岛早期演化的重要信息不仅促进了东北亚早期地体格局的重建,而且深刻影响了需要基于准确地质信息之上的资源探查活动(Zhao et al.,2012; Zhai and Santosh,2013)。

长期以来,朝鲜学者认为朝鲜半岛北部包括两个前寒武纪地块,除占据主体的狼林地块之外,东北部咸镜地区可能还存在一个微陆块,即冠帽地块(Paek et al.,1996; Chough et al.,2000; 梁道俊和刘永江,2009)。由于缺少准确的年代学证据,两个地块之间的关系依然扑朔迷离。此外,鉴于冠帽地块涵盖的区域总体上位于显生宙中亚造山带的东段(图 1b),其构造属性尚存在"造山带"或"褶皱带"等截然不同的看法(Zhang et al.,20042005)。针对冠帽地块构造属性的这些歧异,本次研究我们拟选择该地块之上的前寒武纪岩石建造开展锆石U-Pb年代学和岩石地球化学研究。研究认识不仅有助于甄别冠帽地块的构造属性,而且对于增进中朝克拉通早期大地构造格局的理解具有重要意义。

2 区域地质背景

朝鲜半岛大体呈现由前寒武纪地块与显生宙造山带间列分布的条块镶嵌格局(图 1c)。三个主要地块自北向南分别为狼林地块、京畿地块和岭南地块(Paek et al.,1996);显生宙造山带则包括东北部的豆满江造山带(或图们江褶皱带)(金炳成等,2012; 张晓晖等,2016)、中部东西向延展的临津江带和南部呈北东走向的沃川造山带(Cluzel,1992; Chang,1996; Paek et al.,1996; Chough et al.,2000; Cho et al.,2007; Zhai et al.,2007a)。此外,朝鲜半岛发育两个主要的古生代盆地,即北部的平南盆地和南部的庆尚盆地(Lee and Lee,2003; Zhai et al.,2007a)。

作为朝鲜半岛北部的基本构造单元,狼林地块和临津江带的前寒武纪基底主要包括新太古代-古元古代表壳岩、英云闪长岩-奥长花岗岩-花岗闪长岩(简称TTG)和花岗质变质深成杂岩。依据岩石组合和变质程度的不同,表壳岩可以分为麻粒岩相-高角闪岩相变质的狼林群(Rangnim Group)、角闪岩相变质的甑山群(Jungsan Group)以及绿片岩相/低角闪岩相变质的摩天岭群(Machollyong Group)(Paek et al.,1996; 曹林和朱东,1999)。狼林群主要包括富铝片麻岩、变粒岩夹少量斜长角闪岩、石英岩和大理岩,局部发育麻粒岩与超镁铁变质岩。甑山群是一套以富铝片麻岩和石墨片麻岩为主的孔兹岩系。摩天岭群主要呈NW-SE带状展布于狼林地块东部,自下而上包括三个岩石地层单元,即由大理岩、片岩和角闪岩互层组成的城津组、以厚层碳酸岩为主的北大川组和以陆源碎屑岩组合为主的南大川组(Paek et al.,1996)。与上述表壳岩伴生的深成侵入杂岩包括TTG片麻岩、石榴石/矽线石S型花岗岩、二长花岗岩、钾长花岗岩和斑状花岗岩等(Zhao et al.,2006; Wu et al.,2007a; Zhai et al.,2007b)。锆石U-Pb测年显示TTG片麻岩侵位于2.64~2.54Ga,S型花岗岩侵位于1.91~1.90Ga,而斑状花岗岩形成于1.87~1.81Ga(Zhao et al.,2006; Wu et al.,2007a; Zhai et al.,2007b)。

鉴于各地前寒武纪变质岩系的区域性差异,有些朝鲜学者提出将发育有前寒武纪变质岩系的冠帽峰一带单独命名为冠帽(Kwanmo)地块(Paek et al.,1996; Chough et al.,2000),其中的前寒武纪变质建造主要由茂山群(Mushan)表壳岩和相关变质侵入杂岩组成。茂山群是一套经历低角闪岩相-角闪岩相变质作用的火山沉积建造,主要包括条带状铁建造、石墨片岩、长英质片麻岩和斜长角闪岩。除此之外,该地块大部分区域由主要在侏罗纪侵位的冠帽峰复合岩基和新生代火山岩所占据(Zhai et al.,2016)。

冠帽地块以输城川(Susongchon)断裂为界与咸北(Hambuk)地块毗邻(图 1c)。咸北地块以发育一系列晚古生代以来的火山沉积建造和侵入岩浆活动为特征(Paek et al.,1996; Wu et al.,2007a),故又得名"豆满江造山带",被认为属于中亚造山带的东南延伸(Paek et al.,1996; 金炳成等,2012; 张晓晖等,2016)。这些造山带型的岩浆沉积记录包括:大致形成于早二叠世-中三叠世的豆满群火山沉积建造(金炳成等,2012; 张晓晖等,2016)、形成于晚二叠世-侏罗纪的清津超基性-基性杂岩(作者未发表资料)、以花岗岩为主的中生代豆满江侵入杂岩。

图 1 中朝克拉通构造位置图(a)、华北克拉通东部与朝鲜半岛前寒武纪地质简图(b,据Zhao et al.,2005修改)、朝鲜半岛构造分区简图(c,据Zhao et al.,2006修改)和冠帽地块地质简图(d,据IGSASDPRK,1993修改) Fig. 1 The tectonic location of the Sino-Korean Craton(a),sketch Precambrian geological map of the eastern North China Craton and Korean Peninsula(b,modified after Zhao et al.,2005),tectonic subdivisions of the Korean Peninsula(c,after Zhao et al.,2006)and sketch geological map of the Kwanmo Massif(d,modified after IGSASDPRK,1993)
3 样品及其岩相学特征

我们考察的变质杂岩位于清津市罗南区银德洞一带,其呈近南北向展布,岩石普遍发育糜棱结构,片麻状和条带状构造。根据野外产出状态大体可以分为两套岩石组合。早期中基性片麻岩主要包括斜长角闪岩、角闪斜长片麻岩、黑云斜长片麻岩(图 2a)和石英闪长质片麻岩(图 2b)。其中,黑云斜长片麻岩的片理产状为350°∠35°。晚期长英质片麻岩包括强烈变形的钾长花岗岩岩脉(图 2c)和伟晶岩脉,花岗质糜棱岩中可见石英拔丝现象,线理产状为270°∠20°。此外,野外还可以观察到晚期未变形花岗岩侵入变质杂岩的情形。

图 2 朝鲜半岛冠帽地块银德洞变质侵入杂岩的野外露头照片与显微结构照片 (a)黑云斜长片麻岩;(b)石英闪长质片麻岩;(c)钾长花岗质片麻岩;(d)样品13NK-100;(e)样品13NK-105;(f)样品13NK-111. 矿物缩写:Pl-斜长石;Kfs-钾长石;Qz-石英;Amp-角闪石;Py-辉石;Bt-黑云母 Fig. 2 Field photographs and representative sample photomicrographs of the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula (a)biotite plagioclase gneiss;(b)quartz dioritic gneiss;(c)granitic gneiss;(d)sample 13NK-100;(e)sample 13NK-105;(f)sample 13NK-111

样品13NK-100为黑云斜长片麻岩(图 2d)。岩石具不等粒结构,片麻状构造;主要矿物组成包括斜长石(40%)、黑云母(25%)、石英(20%)和钾长石(10%)。交代现象发育。斜长石主要呈他形粒状,可见眼球状残斑;黑云母呈细小鳞片状和较大的片状,具定向性;钾长石的小颗粒多呈集合体填充在大颗粒钾长石的空隙中;石英颗粒大部分呈拉长的透镜状、条带状齿形粒状集合体,粒内波状消光、亚颗粒发育。副矿物主要有榍石、锆石、磁铁矿和磷灰石等。

样品13NK-105为石英闪长质片麻岩(图 2e)。岩石呈灰黑色,半自形不等粒结构,条带状构造;主要组成矿物有斜长石(40%)、角闪石(20%)、石英(25%)、微斜长石(10%)、黑云母(10%);次要矿物可见紫苏辉石(2%);副矿物主要有锆石、磁铁矿和磷灰石等。斜长石呈半自形-他形粒状。石英呈他形粒状,具有不均匀消光、波状消光,局部可见石英亚颗粒集合体,分布于长石或角闪石颗粒之间。角闪石呈黄褐绿色多色性;黑云母为黄褐红棕色的片状。黑云母和角闪石具有明显定向排列,与浅色矿物呈条带状构造。辉石呈他形粒状,多分布于角闪石颗粒边缘,可能属于原岩的残余;角闪石中存在石英微粒的特征也表明其由辉石变质而形成(Wan et al.,2013)。

样品13NK-111为钾长花岗质片麻岩(图 2f)。岩石呈浅肉红色,糜棱结构,片麻状构造;矿物定向排列明显,石英定向拔丝拉长,局部有眼球状长石斑晶。岩石主要矿物组成为石英(35%)、钾长石(45%)、斜长石(10%)及黑云母(5%);副矿物主要有锆石、榍石和磷灰石等。钾长石为他形粒状,成分为微斜长石;石英为他形粒状,与斜长石呈集合体分布;斜长石呈他形粒状,具有定向拉长变形;黑云母呈不规则状及鳞片状,大部分发生绿泥石化。

图 3 朝鲜半岛冠帽地块银德洞变质侵入杂岩中锆石的阴极发光图像 (a)样品13NK-100(黑云斜长片麻岩);(b)样品13NK-105(石英闪长质片麻岩);(c)样品13NK-111(花岗质片麻岩) Fig. 3 Cathodoluminescence images of zircons from the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula (a)Sample 13NK-100(biotite plagioclase gneiss);(b)Sample 13NK-105(quartz dioritic gneiss);(c)Sample 13NK-111(granitic gneiss)
4 分析方法

锆石采用常规磁选和重液方法分选,并且在双目镜下挑纯后,与标样锆石一起制靶。样品靶制成后,首先在光学显微镜下对被测样品进行照相(包括透射光和反射光),然后在扫描电镜实验室进行锆石阴极发光(CL)图像分析。锆石单矿物挑选在河北省廊坊市区域地质调查研究所实验室完成,制靶工作、反射光、透射光和CL阴极发光照片采集分别在中国科学院地质与地球物理研究所离子探针实验室和扫描电镜实验室完成。

锆石SIMS U-Pb分析在中国科学院地质与地球物理研究所离子探针实验室Cameca IMS-1280二次离子质谱仪上完成。应用SIMS进行U-Th-Pb分析的详细流程参见Li et al.(2009) 。应用标准锆石Plésovice(Slámaet al.,2008)进行元素间的分馏校正,应用标准锆石Qinghu(Li et al.,2010)检测数据精确度,实测204Pb值用于普通Pb校正;采用ISOPLOT软件进行数据处理和年龄计算(Ludwig,2001)。

全岩主量元素在中国科学院地质与地球物理研究所岩矿制样与分析实验室完成,采用Shimadzu 1500型X荧光光谱仪,分析精度优于3%。微量元素测试在中国科学院地质与地球物理研究所电感耦合等离子质谱实验室完成,采用电感耦合等离子质谱(ICPMS)分析方法,具体分析流程参见Yang et al.(2005)

锆石Lu-Hf同位素测试在中国科学院地质与地球物理研究所配有193nm激光取样系统的Neptune多接收电感耦合等离子体质谱仪(MC-ICP-MS)上进行,仪器运行条件与详细测试流程参见Wu et al.(2006) 。测试时采用锆石国际标样91500作为外标,激光束斑直径为63μm,激光脉冲速率为6~8Hz,激光束脉冲能量为100mJ;采用标样MUD(176Hf/177Hf=0.282833±25,2σ)和GJ-1(176Hf/177Hf=0.282020±25,2σ)监测仪器稳定性。

5 分析结果 5.1 锆石U-Pb定年

SIMS锆石U-Pb定年结果如表 1所示。样品13NK-100中的锆石大部分为无色透明的短柱状晶体,粒度为100~300μm,长宽比介于1∶1~3∶1;在CL图像上大部分锆石呈现明显的核边结构(图 3a);颜色较浅的核部可见残留的岩浆振荡环带,颜色较深的边部则无明显结构。11个核部分析点给出的Th/U比值为0.32~0.64,介于岩浆成因锆石的Th/U比值范围(Belousova et al.,2002);给出的207Pb/206Pb年龄变化于2508±5Ma~2539±4Ma之间,8个基本谐和分析点的加权平均年龄为2534±6Ma,与上交点年龄在误差范围内基本一致(图 4a)。因此,该加权年龄可能代表片麻岩原岩侵位的结晶年龄。其余13个边部分析点给出的Th/U为0.12~0.44,207Pb/206Pb年龄介于2457±4Ma~2482±3Ma,可能记录了引起锆石发生变质重结晶的构造热事件。

表 1 朝鲜半岛冠帽地块银德洞变质侵入杂岩中锆石SIMS U-Th-Pb分析数据 Table 1 SIMS zircon U-Th-Pb analytical data for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula

样品13NK-105中的锆石大部分为自形-半自形柱状晶体,粒度为80~200μm;在CL图像上,部分锆石呈现核边结构,大部分锆石具有明显的岩浆振荡环带(图 3b)。22个核部分析点给出的Th/U比值为0.35~1.11,207Pb/206Pb年龄介于2511±7Ma~2538±10Ma之间,19个基本谐和分析点的加权平均年龄为2529±2Ma,与上交点年龄在误差范围内基本一致(图 4b)。因此,该加权年龄可能代表石英闪长质片麻岩原岩的侵位年龄。其余3个边部分析点给出的Th/U为0.12~0.46,207Pb/206Pb年龄介于2439±4Ma~2463±4Ma,可能因后期变质重结晶事件导致Pb丢失而引起年龄降低。

图 4 朝鲜半岛冠帽地块银德洞变质侵入杂岩中锆石的U-Pb年龄谐和图 (a)样品13NK-100(黑云斜长片麻岩);(b)样品13NK-105(石英闪长质片麻岩);(c)样品13NK-111(花岗质片麻岩) Fig. 4 U-Pb age diagrams for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula (a)Sample 13NK-100(biotite plagioclase gneiss);(b)Sample 13NK-105(quartz dioritic gneiss);(c)Sample 13NK-111(granitic gneiss)

样品13NK-111中的锆石为自形-半自形的短柱状晶体,粒度为80~200μm,长宽比介于1∶1~2∶1;在CL图像上大部分锆石发育岩浆振荡环带(图 3c);部分锆石具核边结构,部分锆石显示弱宽环带或冷杉叶状环带(图 3c)。11个具有岩浆振荡环带的颗粒核部分析点给出的Th/U为0.39~0.87,207Pb/206Pb年龄介于2496±10Ma~2530±5Ma之间,加权平均年龄为2514±6Ma,与上交点年龄在误差范围内基本一致(图 4c)。因此,该加权年龄可能代表钾长花岗质片麻岩的原岩侵位年龄。4个边部分析点给出的Th/U为0.16~0.39,207Pb/206Pb年龄介于2445±3Ma~2482±4Ma,可能归因于后期构造热事件扰动引起的Pb丢失。此外,5个具有弱宽环带锆石分析点给出的Th/U为0.27~0.59,206Pb/238Pb年龄介于436±6Ma~444±6Ma,加权平均年龄为442±6Ma,可能记录了一次引起锆石固态重结晶的构造热事件。

5.2 主微量元素特征

3个样品的全岩主微量元素分析结果见表 2。样品13NK-100的SiO2=61.46%、TiO2=0.82%、Fe2O3T=10.1%、MgO=1.37%、Al2O3=15.1%、Na2O=4.27%、CaO=3.05%、K2O=2.91%和P2O5=0.29%;样品13NK-105的SiO2=63.2%、Al2O3=13.7%、Na2O=3.17%、Fe2O3T=8.23%、MgO=2.76%、CaO=4.52%、TiO2=0.67%、K2O=2.4%和P2O5=0.17%;样品13NK-111的SiO2=75.1%、Fe2O3T=0.68%、MgO=0.13%、Al2O3=13.1%、CaO=0.76%、TiO2=0.06%、Na2O=2.97%、K2O=6.13%和P2O5=0.01%。在CIPW标准矿物An-Ab-Or分类图中(Barker,1979),3个样品落入花岗闪长岩和花岗岩区域(图 5a);铁指数[(FeO+0.9Fe2O3)/(FeO+0.9Fe2O3+MgO)]变化于0.73~0.87(图 5b);在SiO2-(Na2O+K2O-CaO)图中(图 5c),3个样品属于钙碱性-碱钙性系列;其铝饱和指数A/CNK介于0.96~1.01,为准铝质到弱过铝质(图 5d)。

表 2 朝鲜半岛冠帽地块银德洞变质侵入杂岩的主量元素(wt%)和微量元素(×10-6)组成 Table 2 Major(wt%)and trace(×10-6)element composition for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula

在稀土元素球粒陨石标准化图解中(图 6a),3个样品呈现LREE弱富集的配分模式((La/Yb)N=3.51~7.72),并具有弱负铕异常(Eu/Eu*=0.37~0.89)。在微量元素原始地幔标准化蛛网图(图 6b)中,3个样品均富集大离子亲石元素(LILE)Rb、Th、U;不同程度的富集Zr、Hf、Nb,但亏损Ti,并强烈富集Pb。

图 6 朝鲜半岛冠帽地块银德洞变质侵入杂岩的球粒陨石标准化稀土元素配分模式图(a)和原始地幔标准化微量元素蛛网图(b)(标准化值据Sun and McDonough,1989) Fig. 6 Chondrite-normalized REE patterns(a)and primitive mantle-normalized trace element spidergrams(b)(normalization values after Sun and McDonough,1989)for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula
5.3 锆石Hf同位素特征

3个样品的锆石Hf同位素分析结果见表 3。样品13NK-100中锆石的176Hf/177Hf变化于0.281154~0.281380;计算得到的初始176Hf/177Hf值介于0.281112~0.281338,εHf(t)值变化于-0.3~+4.5(图 7a),Hf亏损地幔模式年龄(tDMHf)为2.61~2.91Ga,地壳模式年龄(tDMC)介于2.71~3.17Ga(图 7b)。样品13NK-105中锆石的176Hf/177Hf比值变化于0.281175~0.281455,176Hf/177Hfi比值介于0.281137~0.281404,εHf(t)变化于-1.7~+8.2(图 7a),tDMHf为2.52~2.88Ga,tDMC介于2.52~3.13Ga(图 7b)。样品13NK-111中锆石的176Hf/177Hf值为0.281247~0.281510;176Hf/177Hfi比值介于0.281206~0.281474,εHf(t)变化于+0.7~+10.5(图 7a),tDMHf为2.42~2.78Ga,tDMC介于2.38~2.96Ga(图 7b)。

表 3 朝鲜半岛冠帽地块银德洞变质侵入杂岩的锆石Lu-Hf同位素组成 Table 3 In-situ zircon Lu-Hf isotopic data for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula

图 5 朝鲜半岛冠帽地块银德洞变质侵入杂岩的主量元素分类图解 (a)Ab-An-Or分类图(Barker et al.,1979);(b)SiO2-FeOT/(FeOT+MgO)分类图(Frost et al.,2001);(c)SiO2-(Na2O+K2O-CaO)分类图(Frost et al.,2001);(d)A/NK-A/CNK分类图 Fig. 5 Geochemical discrimination diagrams for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula

图 7 朝鲜半岛冠帽地块银德洞变质侵入杂岩的锆石Hf同位素图解 (a)锆石εHf(t)vs. 207Pb/206Pb年龄图,其中的华北克拉通东部新太古代锆石Hf同位素数据范围来自Wan et al.(2015) ;(b)锆石Hf同位素模式年龄图,其中的狼林地块河砂中碎屑锆石的Hf同位素模式年龄数据来自Wu et al.(2007b) Fig. 7 Plots of zircon Hf isotope for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula (a)plot of zircon εHf(t)vs. 207Pb/206Pb age,the field for the Neoarchean zircons of eastern NCC from Wan et al.(2015) ;(b)crustal Hf model age histogram for zircons from Archean rocks in Korean Peninsula,data for the detrital zircons of Rangrim massif from Wu et al.(2007b)
6 讨论 6.1 年龄解释

对于零星分布于冠帽地块和咸北地块的前寒武纪变质建造,朝鲜地质学界一直将其统归为茂山群表壳岩系(Paek et al.,1996)。但实际上,这些变质建造在不同地区产状各异,岩石组成迥然有别,变质程度也不尽相同。除在中朝边境茂山一带发育的茂山群可能属于一套经历低角闪岩相变质作用的典型火山沉积建造之外,其他地区的变质建造多以构造块体或包体产出于显生宙火山沉积建造或花岗岩之中,岩石类型主要包括黑云角闪斜长片麻岩、花岗闪长质片麻岩、花岗质片麻岩等,混合岩化或糜棱岩化作用强烈(Paek et al.,1996; 金正男等,2006)。

清津西南银德洞的变质杂岩露头就是如此。其宏观岩石特征、接触关系及微观组构均呈现侵入成因特点,应为变质的深成侵入体。首先,野外可以观察到花岗质片麻岩到闪长质片麻岩的渐变过渡,也可观察到晚期钾长花岗岩侵入早期中基性单元的明显切割关系;其次,杂岩体的各组成岩性比较均匀,保留有岩浆岩的结构和构造特征。

与上述侵入岩成因特征相一致,本文测试的中酸性片麻岩中的锆石核部保留了原岩密集的岩浆震荡环带,并具有高的Th/U比值,因此它们为岩浆成因锆石,所测得的年龄应代表变质杂岩原岩侵位的年龄。定年结果表明,两个闪长质片麻岩的年龄为2.53Ga,而较晚的钾长花岗质片麻岩的年龄为2.51Ga,它们代表了清津银德洞变质杂岩的原岩结晶年龄。此外,3个样品中深溶成因锆石幔部记录的加权平均年龄为2.48Ga,应该代表引起区域变质作用的构造热事件的年龄。

6.2 原岩性质与形成环境

对于全面论证银德洞变质侵入杂岩的成因机制,本文仅有的3个样品尽管力有不逮,但其鲜明的岩石地球化学特征仍然昭示了其独特的形成过程。

除含有紫苏辉石的矿物组成特征之外,地球化学分析结果显示,两个中性片麻岩呈现从铁质到镁质,从钙碱性到碱钙性的变化;而花岗质片麻岩为铁质、钙碱性及弱过铝质。其成分不仅契合岩浆成因紫苏花岗岩变化很大的一般成分范围(Frost and Frost,2008; Rajesh,2012),而且与印度南部世界最典型岩浆型紫苏花岗岩岩套的成分相当(Rajesh,20072012; Tomson et al.,2013)。就微量元素而言,无论是轻重稀土中等分馏和Eu负异常显著的稀土元素特征,还是Nb、Zr、Th、U富集的其他微量元素地球化学行为,都与世界上众多典型太古代和元古代紫苏花岗岩系列相一致(Rajesh,2007; Tomson et al.,2013; Zhang et al.,2014; Zhao et al.,2014)。

岩浆型紫苏花岗岩系列宽泛的岩石地球化学特征决定了其复杂多样的形成过程(Frost and Frost,2008)。综合地球上不同时期重要紫苏花岗岩系列的成因,大体可以归因于两类主要机制,一是幔源拉斑玄武质岩浆的分异;二是镁铁质下地壳岩石在高温高压和富CO2流体下的部分熔融及其后的结晶分异(Frost and Frost,2008; Rajesh,2012; Zhang et al.,20102014; Zhao et al.,2014)。

拉斑玄武质岩浆分异而成的紫苏花岗岩通常与斜长岩、纹长二长岩以及花岗岩伴生构成斜长岩-纹长二长岩-紫苏花岗岩-花岗岩岩套(AMGC)(Emslie,1991),成分上主要表现为铁质和碱性,在组成上以幔源岩石为主,并与大陆裂谷环境具有密切的亲缘关系(Frost and Frost,2008)。

银德洞片麻岩系列既无斜长岩等伴生岩石,又兼具镁/铁质和钙碱性-碱钙性的复杂地球化学特征;结合镁铁质岩部分熔融形成的典型太古代紫苏花岗岩实例(Frost et al.,2000; Rajesh,2007; Feio et al.,2012; Zhang et al.,2014),我们推测银德洞片麻岩系列可能形成于镁铁质下地壳岩石在高温和富CO2流体下的部分熔融及其后的结晶分异。

根据Frost and Frost(2008) 的系统总结,此类中酸性侵入岩或者构成强烈剥蚀的Cordlleran型深成侵人岩的一部分;或者属于热的铁质岩浆侵人引起的深部地壳部分熔融的标志性产物。前者通常产出于大陆岩浆弧环境(Barnes et al.,2006);譬如加拿大北魁北克的太古代Utsalik(Percival and Mortensen,2002)和Desliens(Percival et al.,2003)岩基、南极洲的元古代Mawson岩基(Young et al.,1997)、美国怀俄明风河山脉的太古代Louis Lake岩基(Frost et al.,2000)、以及华北克拉通阴山地块的新太古代紫苏花岗岩(Zhang et al.,2014);显生宙实例则包括美国Klamath山脉的侏罗纪Ironside岩基(Barnes et al.,2006)、青藏高原冈底斯带南缘的晚白垩世紫苏花岗岩(Zhang et al.,2010)等。这些紫苏花岗岩系列的同位素特征一致指示,其源区兼具新生地壳与古老地壳物质的双重属性(Frost and Frost,2008),体现了活动大陆边缘背景岩浆源区的典型特征。

银德洞中酸性片麻岩系列不仅呈现与活动大陆边缘俯冲环境相契合的元素地球化学印记(图 8),而且具有相应的双重物源属性。如前所述,3个样品的锆石εHf(t)值变化于-1.7~+10.5,Hf同位素地壳模式年龄介于2.52~3.17Ga,说明其源区既以新生下地壳物质为主,又有一定的古老地壳物质贡献。

图 8 朝鲜半岛冠帽地块银德洞变质侵入杂岩的构造环境判别图 (a)Y-Nb(Pearce italic>et al.,1984);(b)Zr-Nb/Zr(Thiéblemont and Tegyey,1994).南印度新太古代紫苏花岗岩系列范围来自Rajesh(2012) Tomson et al.(2013) Fig. 8 Tectonic discrimination diagrams for the Undokdong meta-intrusive rocks in the Kwanmo Massif,Korean Peninsula (a)Y vs. Nb plot(Pearce et al.,1984);(b)Zr vs. Nb/Zr plot(Thiéblemont and Tegyey,1994). The field for the Neoarchean charnockite suites in the southern India is from Rajesh(2012) and Tomson et al.(2013)

此外,活动大陆边缘岩浆弧环境下形成的紫苏花岗岩通常伴随着程度可达麻粒岩相的高温变质作用(Frost and Frost,2008; Zhang et al.,20102014),反映活动大陆边缘从俯冲到碰撞后伸展的地球动力学演进。银德洞变质杂岩的岩浆侵位年龄和变质年龄可能正是这种活动大陆边缘岩浆弧环境地球动力学过程的响应记录。

6.3 区域对比与地质意义

朝鲜地质学界一直认为太古宙是朝鲜半岛陆核形成和发展的重要时期(Paek et al.,1996; 梁道俊和刘永江,2009),这得到近年来精细年代学研究的陆续证实。一方面,在原以为太古代变质基底占据主体的狼林地块,在先期报道的一些太古宙残留锆石记录的基础上(Zhao et al.,2006; Wu et al.,2007b; 吴福元等,2016),我们近期在地块东部的摩天岭峰一带识别出了成岩年龄为2.56的片麻岩-斜长角闪岩系(Zhang et al.,2016)。另一方面,在据认为成形于古生代的临津江带,发现两处年龄分别约为2.54Ga和2.64Ga的太古宙片麻岩(Zhao et al.,2006)。Cho et al.(2008) 也在京畿地块西部Daeijak岛确定了结晶年龄为2.58Ga的英云闪长岩遗存。这些太古宙岩石记录与本文厘定的2.53~2.51Ga的银德洞变质深成侵入体一道,构成了截止目前朝鲜半岛太古宙基底岩石的基本分布格局。

与朝鲜半岛这些零星的太古宙岩石记录相对照,太古宙却是华北克拉通东部陆块基底建造发展的重要时期。在辽宁北部的抚顺-清原地区,详细年代学研究揭示,大面积分布的TTG岩石大约在2.57~2.49Ga侵位,间或少量2.52~2.50Ga的钾质花岗岩,并伴生同时期的高级变质作用(万渝生等,2005; Miao et al.,2005; Grant et al.,2009; 白翔等,2014; Peng et al.,2015)。在吉林省东部的和龙地区,TTG岩石及其中的表壳岩系分别形成于2.55~2-53Ga和2.68~2.65Ga,并于2.51~2.40Ga发生区域变质作用(Guo et al.,2015)。在吉林南部的桦甸-龙岗地区,除发育尚没有精确年龄的大面积太古宙花岗质片麻岩之外(吴福元等,1997),与条带状铁矿伴生的镁铁质侵入体形成于2.53Ga左右(邵建波等,2014)。

在与狼林地块毗邻的辽宁南部地块,除早期厘定的大约形成于2.44~2.50Ga的闪长质-花岗闪长质片麻岩(路孝平等,2004)之外,Meng et al.(2013ab)近期的精细年代学研究揭示,位于辽东半岛东侧海域、由两百多个岛屿组成的长山群岛发育两种不同类型的太古宙变质基底,其中钠质花岗片麻岩的成岩年龄集中在2537~2544Ma,钾质花岗岩形成于2517~2514Ma。

虽然基于上述太古宙基底建造的分布格局重现朝鲜半岛与华北克拉通的早期关联历史超出本文范畴,但重构中朝克拉通早期地壳演化图景的几条线索可见端倪。其一,银德洞变质杂岩属于新太古代岩浆弧根部岩浆建造的研究认识表明,冠帽地块在基底建造特征方面与吉南和龙地块(Guo et al.,2015)和辽北清原地块(Peng et al.,2015)等存在密切的亲缘性,暗示它们在新太古代共同处在一个类似于安第斯活动大陆边缘的构造环境(Zhai and Windley,1990; Guo et al.,2015; Peng et al.,2015)。其二,尽管辽吉活动带两侧的地块共享新太古代变质基底建造,但古元古代演化却呈现分野之势。在活动带之南(现今地理位置)的辽南地块和狼林地块,新太古代结晶基底普遍叠加了1.85~1.95Ga的变质事件(Zhao et al.,2006; Li and Zhao,2007; Li et al.,2012; Meng et al.,2013ab; Peng et al.,2014; 刘福来等,2015);而在活动带以北的清原地块(Peng et al.,2015)、和龙地块(Guo et al.,2015)和冠帽地块,迄今未发现任何该期变质事件的痕迹。其三,和龙地块和冠帽地块虽然发育确切的太古宙基底建造,但其主体毕竟被显生宙花岗岩所占据,新生地壳物质主宰这些花岗岩物源的事实(Zhang et al.,2005; Wu et al.,2007a)表明,二个地块实质上可能是残存在显生宙造山带中的太古宙块体(吴福元等,2016)。

7 结论

(1) 朝鲜清津银德洞的变质基底建造是一套中酸性的变质深成侵入杂岩,原岩组成可能包括石英闪长岩和钾长花岗岩;系统的锆石U-Pb年代学研究揭示,它们形成于2.53~2.51Ga。

(2) 银德洞变质深成侵入杂岩的岩石地球化学特征大体上可与世界最典型岩浆型紫苏花岗岩套相类比。这表明银德洞变质侵入杂岩可能形成于镁铁质下地壳岩石在高温和富CO2流体下的部分熔融及其后的结晶分异,代表了活动大陆边缘岩浆弧环境下的典型产物。

(3) 银德洞变质杂岩属于新太古代岩浆弧根部岩浆建造的研究认识表明,冠帽地块在基底建造特征方面与华北克拉通东部吉南和龙地块及辽北清原地块等存在密切的亲缘性,暗示它们在新太古代共同处在一个安第斯型活动大陆边缘环境。

致谢 刘富博士参与了朝鲜野外地质考察工作;耿元生研究员和万渝生研究员的建设性修改意见使文章臻于完善;在此谨致衷心谢忱。
参考文献
[1] Bai X, Liu SW, Yan M, Zhang LF, Wang W, Guo RR, Guo BR. 2014. Geological event series of Early Precambrian metamorphic complex in South Fushun area, Liaoning Province. Acta Petrologica Sinica , 30 (10) :2905–2924.
[2] Barker F.1979. Trondhjemite:Definition, environment and hypotheses of origin. In: Barker F (ed.). Trondhjemites, Dacites and Related Rocks. Amsterdam:Elsevier .
[3] Barnes CG, Mars EV, Swapp S, Frost CD. 2006. Petrology and geochemistry of the Middle Jurassic Ironside Mountain batholith:Evolution of potassic magmas in a primitive arc setting. Special Papers-Geological Society of America , 410 :199–221.
[4] Belousova EA, Griffin WL, O'Reilly SY, Fisher NI. 2002. Igneous zircon:Trace element composition as an indicator of source rock type. Contributions to Mineralogy and Petrology , 143 (5) :602–622. DOI:10.1007/s00410-002-0364-7
[5] Cao L, Ju D. 1999. The comparison and evolutionary phases of the Early Precambrian metamorphic rock system in eastern China-Korea paleocontinent. World Geology , 18 (2) :36–46.
[6] Chang EZ. 1996. Collisional orogene between north and south China and its eastern extension in the Korean Peninsula. Journal of Southeast Asian Earth Sciences , 13 (3-5) :267–277. DOI:10.1016/0743-9547(96)00033-5
[7] Cho M, Kim Y, Ahn J. 2007. Metamorphic evolution of the Imjingang belt, Korea:Implications for Permo-Triassic collisional orogeny. International Geology Review , 49 (1) :30–51. DOI:10.2747/0020-6814.49.1.30
[8] Cho M, Kim H, Lee Y, Horie K, Hidaka H. 2008. The oldest (ca. 2.51Ga) rock in South Korea:U-Pb zircon age of a tonalitic migmatite, Daeijak Island, western Gyeonggi massif. Geosciences Journal , 12 (1) :1–6.
[9] Chough SK, Kwon ST, Ree JH, Choi DK. 2000. Tectonic and sedimentary evolution of the Korean peninsula:A review and new view. Earth-Science Reviews , 52 (1-3) :175–235. DOI:10.1016/S0012-8252(00)00029-5
[10] Cluzel D. 1992. Ordovician bimodal magmatism in the Ogcheon belt (South Korea):Intracontinental rift-related volcanic activity. Journal of Southeast Asian Earth Sciences , 7 (2-3) :195–209. DOI:10.1016/0743-9547(92)90054-F
[11] Emslie RF. 1991. Granitoids of rapakivi granite-anorthosite and related associations. Precambrian Research , 51 (1-4) :173–192. DOI:10.1016/0301-9268(91)90100-O
[12] Feio GRL, Dall' Agnol R, Dantas EL, Macambira MJB, Gomes ACB, Sardinha AS, Oliveria DC, Santos RD, Santos PA. 2012. Geochemistry, geochronology, and origin of the Neoarchean Planalto Granite suite, Carajás. Amazonian craton:A-type or hydrated charnockitic granites? Lithos , 151 :57–73.
[13] Frost BR, Frost CD, Hulsebosch TP, Swapp SM. 2000. Origin of the charnockites of the Louis Lake batholith, Wind River Range, Wyoming. Journal of Petrology , 41 (12) :1759–1776. DOI:10.1093/petrology/41.12.1759
[14] Frost BR, Barnes CG, Collins WJ, Arculus RJ, Ellis DJ, Frost CD. 2001. A geochemical classification for granitic rocks. Journal of Petrology , 42 (11) :2033–2048. DOI:10.1093/petrology/42.11.2033
[15] Frost BR, Frost CD. 2008. On charnockites. Gondwana Research , 13 (1) :30–44. DOI:10.1016/j.gr.2007.07.006
[16] Grant ML, Wilde SA, Wu FY, Yang JH. 2009. The application of zircon cathodoluminescence imaging, Th-U-Pb chemistry and U-Pb ages in interpreting discrete magmatic and high-grade metamorphic events in the North China Craton at the Archean/Proterozoic boundary. Chemical Geology , 261 (1-2) :155–171. DOI:10.1016/j.chemgeo.2008.11.002
[17] Guo BR, Liu SW, Zhang J, Yan M. 2015. Zircon U-Pb-Hf isotope systematics and geochemistry of Helong granite-greenstone belt in southern Jilin Province, China:Implications for Neoarchean crustal evolution of the northeastern margin of North China Craton. Precambrian Research , 271 :254–277. DOI:10.1016/j.precamres.2015.10.009
[18] Horie K, Tsutsumi Y, Kim H, Cho M, Hidaka H, Terada K. 2009. A U-Pb geochronological study of migmatitic gneiss in the Busan gneiss complex, Gyeonggi massif, Korea. Geosciences Journal , 13 (3) :205–215. DOI:10.1007/s12303-009-0021-5
[19] IGSASDPRK (Institute of Geology, State Academy of Sciences, DPR of Korea). 1993. 1:1000000 Geological Map of Korea. Pyongyang:Foreign Languages Books Publishing House
[20] Kim BS, Liu YJ, Han GQ, Kim JY. 2012. Late Paleozoic sedimentary characteristics in Yanji-Jilin-Hambuk area, Korea and its significance to tectonic evolution. Journal of Jilin University (Earth Science Edition) , 42 (Suppl) :296–305.
[21] Kim J, Cho M. 2003. Low-pressure metamorphism and leucogranite magmatism, northeastern Yeongnam massif, Korea:Implication for Paleoproterozoic crustal evolution. Precambrian Research , 122 (1-4) :235–251. DOI:10.1016/S0301-9268(02)00213-9
[22] Kim J, Paek R and Han R. 2006. Precambrian Geology. Pyongyang:Kim Il Sung University Publishing House, 10-13 (in Korean with English abstract)
[23] Kim N, Cheong CS, Park KH, Kim J, Song YS. 2012. Crustal evolution of northeastern Yeongnam Massif, Korea, revealed by SHRIMP U-Pb zircon geochronology and geochemistry. Gondwana Research , 21 (4) :865–875. DOI:10.1016/j.gr.2011.10.003
[24] Kim SW, Williams IS, Kwon S, Oh CW. 2008. SHRIMP zircon geochronology, and geochemical characteristics of metaplutonic rocks from the south-western Gyeonggi Block, Korea:Implications for Paleoproterozoic to Mesozoic tectonic links between the Korean Peninsula and eastern China. Precambrian Research , 162 (3-4) :475–497. DOI:10.1016/j.precamres.2007.10.006
[25] Kim SW, Kwon S, Yi K, Santosh M. 2014. Arc magmatism in the Yeongnam massif, Korean Peninsula:Imprints of Columbia and Rodinia supercontinents. Gondwana Research , 26 (3-4) :1009–1027. DOI:10.1016/j.gr.2013.08.020
[26] Lee BC, Oh CW, Yengkhom KS, Yi K. 2014. Paleoproterozoic magmatic and metamorphic events in the Hongcheon area, southern margin of the Northern Gyeonggi Massif in the Korean Peninsula, and their links to the Paleoproterozoic orogeny in the North China Craton. Precambrian Research , 248 :17–38. DOI:10.1016/j.precamres.2014.04.003
[27] Lee DS.1987. Geology of Korea. Seoul: Geological Society of Korea, Kyohak-Sa Publishing Corporation : 1 -514.
[28] Lee SG, Shin SC, Jin MS, Ogasawara M, Yang MK. 2005. Two Paleoproterozoic strongly peraluminous granitic plutons (Nonggeori and Naedeokri granites) at the northeastern part of Yeongnam Massif, Korea:Geochemical and isotopic constraints in East Asian crustal formation history. Precambrian Research , 139 (1-2) :101–120. DOI:10.1016/j.precamres.2005.06.006
[29] Lee SR, Cho M, Yi K, Stern RA. 2000. Early Proterozoic granulites in Central Korea:Tectonic correlation with Chinese Cratons. The Journal of Geology , 108 (6) :729–738. DOI:10.1086/317951
[30] Lee YI, Lee JI. 2003. Paleozoic sedimentation and tectonics in Korea:A review. The Island Arc , 12 (2) :162–179. DOI:10.1046/j.1440-1738.2003.00388.x
[31] Li QL, Li XH, Liu Y, Tang GQ, Yang JH, Zhu WG. 2010. Precise U-Pb and Pb-Pb dating of Phanerozoic baddeleyite by SIMS with oxygen flooding technique. Journal of Analytical Atomic Spectrometry , 25 (7) :1107–1113. DOI:10.1039/b923444f
[32] Li SZ, Zhao GC. 2007. SHRIMP U-Pb zircon geochronology of the LiaoJi granitoids:Constraints on the evolution of the Paleoproterozoic Jiao-Liao-Ji belt in the Eastern Block of the North China Craton. Precambrian Research , 158 (1-2) :1–16. DOI:10.1016/j.precamres.2007.04.001
[33] Li SZ, Zhao GC, Santosh M, Liu X, Dai LM, Suo YH, Tam PY, Song MC, Wang PC. 2012. Paleoproterozoic structural evolution of the southern segment of the Jiao-Liao-Ji Belt, North China Craton. Precambrian Research , 200-203 :59–73. DOI:10.1016/j.precamres.2012.01.007
[34] Li XH, Liu Y, Li QL, Guo CH, Chamberlain KR. 2009. Precise determination of Phanerozoic zircon Pb/Pb age by multicollector SIMS without external standardization. Geochemistry, Geophysics, Geosystems , 10 (4) :Q04010. DOI:10.1029/2009GC002400
[35] Liang DJ, Liu YJ. 2009. Formation and evolution of Early Precambrian crust in Korean Peninsula:Formation stages of palaeocontinent (Ar-Pt1). Global Geology , 28 (3) :271–279.
[36] Liu FL, Liu PH, Wang F, Liu CH, Cai J. 2015. Progresses and overviews of voluminous meta-sedimentary series within the Paleoproterozoic Jiao-Liao-Ji orogenic/mobile belt, North China Craton. Acta Petrologica Sinica , 31 (10) :2816–2846.
[37] Lu XP, Wu FY, Lin JQ, Sun DY, Zhang YB, Guo CL. 2004. Geochronological successions of the Early Precambrian granitic magmatism in southern Liaodong Peninsula and its constraints on tectonic evolution of the North China Craton. Chinese Journal of Geology , 39 (1) :123–138.
[38] Ludwig KR.2001. Squid 1. 02: A User Manual. Berkeley:Berkeley Geochronological Center Special Publication : 19 .
[39] Meng E, Liu FL, Liu JH, Liu PH, Cui Y, Liu CH, Yang H, Wang F, Shi JR, Kong QB, Lian T. 2013a. Zircon U-Pb and Lu-Hf isotopic constraints on Archean crustal evolution in the Liaonan complex of northeast China. Lithos , 177 :164–183. DOI:10.1016/j.lithos.2013.06.020
[40] Meng E, Liu FL, Cui Y, Cai J. 2013b. Zircon U-Pb and Lu-Hf isotopic and whole-rock geochemical constraints on the protolith and tectonic history of the Changhai metamorphic supracrustal sequence in the Jiao-Liao-Ji Belt, southeast Liaoning Province, Northeast China. Precambrian Research , 233 :297–315. DOI:10.1016/j.precamres.2013.05.004
[41] Miao LC, Qiu YM, Fan WM, Zhang FQ, Zhai MG. 2005. Geology, geochronology, and tectonic setting of the Jiapigou gold deposits, southern Jilin Province, China. Ore Geology Reviews , 26 (1-2) :137–165. DOI:10.1016/j.oregeorev.2004.10.004
[42] Niu YL, Liu Y, Xue QQ, Shao FL, Chen S, Duan M, Guo PY, Gong HM, Hu Y, Hu ZX, Kong JJ, Li JY, Liu JJ, Sun P, Sun WL, Ye L, Xiao YY, Zhang Y. 2015. Exotic origin of the Chinese continental shelf:New insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic. Science Bulletin , 60 (18) :1598–1616. DOI:10.1007/s11434-015-0891-z
[43] Oh CW, Kim CB, Park YS, Kim SW. 2006. SHRIMP U-Pb zircon ages of Paleoproterozoic rocks from the Gyeonggi Block and their implications. Journal of Geological Society of Korea , 42 :587–606.
[44] Oh CW, Kusky T. 2007. The Late Permian to Triassic Hongseong-Odesan collision belt in South Korea, and its tectonic correlation with China and Japan. International Geology Review , 49 (7) :636–657. DOI:10.2747/0020-6814.49.7.636
[45] Paek RJ, Kang HG, Jon GP. 1996. Geology of Korea. Pyongyang, Korea:Foreign Languages Books Publishing House :1–631.
[46] Pearce JA, Harris NBW, Tindle AG. 1984. Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. Journal of Petrology , 25 (4) :956–983. DOI:10.1093/petrology/25.4.956
[47] Peng P, Wang XP, Windley BF, Guo JH, Zhai MG, Li Y. 2014. Spatial distribution of ca. 1950~1800Ma metamorphic events in the North China Craton:Implications for tectonic subdivision of the craton. Lithos , 202-203 :250–266.
[48] Peng P, Wang C, Wang XP, Yang SY. 2015. Qingyuan high-grade granite-greenstone terrain in the eastern North China Craton:Root of a Neoarchaean arc. Tectonophysics , 662 :7–21.
[49] Percival JA, Mortensen JK. 2002. Water-deficient calc-alkaline plutonic rocks of northeastern Superior province, Canada:Significance of charnockitic magmatism. Journal of Petrology , 43 (9) :1617–1650. DOI:10.1093/petrology/43.9.1617
[50] Percival JA, Stern RA, Rayner N. 2003. Archean adakites from the Ashuanipi complex, eastern Superior province, Canada:Geochemistry, geochronology and tectonic significance. Contributions to Mineralogy and Petrology , 145 (3) :265–280. DOI:10.1007/s00410-003-0450-5
[51] Rajesh HM. 2007. The petrogenetic characterization of intermediate and silicic charnockites in high-grade terrains:A case study from southern India. Contributions to Mineralogy and Petrology , 154 (5) :591–606. DOI:10.1007/s00410-007-0211-y
[52] Rajesh HM. 2012. A geochemical perspective on charnockite magmatism in Peninsular India. Geoscience Frontiers , 3 (6) :773–788. DOI:10.1016/j.gsf.2012.04.003
[53] Rogers JJW, Santosh M. 2006. The Sino-Korean Craton and supercontinent history:Problems and perspectives. Gondwana Research , 9 (1-2) :21–23. DOI:10.1016/j.gr.2005.04.001
[54] Shao JB, Li JG, Wang HT, Chen DY, Ren Q. 2014. Geological characteristics and zircon U-Pb age of the Wudaoyangcha Neoarchaean vanadic titanomagnetite deposit in Baishan, Jilin Province. Geology in China , 41 (2) :463–483.
[55] Sláma J, Košler J, Condon DJ, Crowley JL, Gerdes A, Hanchar JM, Horstwood MSA, Morris GA, Nasdala L, Norberg N, Schaltegger U, Schoene B, Tubrett MN, Whitehouse MJ. 2008. Plešovice zircon:A new natural reference material for U-Pb and Hf isotopic microanalysis. Chemical Geology , 249 (1-2) :1–35. DOI:10.1016/j.chemgeo.2007.11.005
[56] Sun SS, McDonough WF. 1989. Chemical and isotopic systematics of oceanic basalts:Implications for mantle composition and processes. In:Sanders AD and Norry MJ (eds.). Magmatism in Ocean Basins. Geological Society, London, Special Publication , 42 (1) :313–345. DOI:10.1144/GSL.SP.1989.042.01.19
[57] Thiéblemont D, Tegyey M. 1994. Geochemical discrimination of differentiated magmatic rocks attesting for the variable origin and tectonic setting of calc-alkaline magmas. Sci Terre Planet , 319 :87–94.
[58] Tomson JK, Rao YJB, Kumar TV, Choudhary AK. 2013. Geochemistry and neodymium model ages of Precambrian charnockites, Southern Granulite Terrain, India:Constraints on terrain assembly. Precambrian Research , 227 :295–315.
[59] Wan YS, Song B, Yang C, Liu DY. 2005. Zircon SHRIMP U-Pb geochronology of Archaean rocks from the Fushun-Qingyuan area, Liaoning Province and its geological significance. Acta Geologica Sinica , 79 (1) :78–87.
[60] Wan YS, Xu ZY, Dong CY, Nutman A, Ma MZ, Xie HQ, Liu SJ, Liu DY, Wang HC, Cu H. 2013. Episodic Paleoproterozoic (~2. 45,~1.95 and~1.85Ga) mafic magmatism and associated high temperature metamorphism in the Daqingshan area, North China Craton:SHRIMP zircon U-Pb dating and whole-rock geochemistry. Precambrian Research , 224 :71–93.
[61] Wan YS, Liu DY, Dong CY, Xie HQ, Kröner A, Ma MZ, Liu SJ, Xie SW, Ren P. 2015. Formation and evolution of Archean continental crust of the North China craton. In:Zhai MG (ed.). Precambrian Geology of China:Springer Geology. Berlin, Heidelberg:Springer-Verlag :59–136.
[62] Wu FY, Ge WC, Sun DY, Lin Q, Zhou Y. 1997. The Sm-Nd, Rb-Sr isotopic ages of the Archean granites in southern Jilin Province. Acta Petrologica Sinica , 13 (4) :499–506.
[63] Wu FY, Yang YH, Xie LW, Yang JH, Xu P. 2006. Hf isotopic compositions of the standard zircons and baddeleyites used in U-Pb geochronology. Chemical Geology , 234 (1-2) :105–126. DOI:10.1016/j.chemgeo.2006.05.003
[64] Wu FY, Han RH, Yang JH, Wilde SA, Zhai MG, Park SC. 2007a. Initial constraints on the timing of granitic magmatism in North Korea using U-Pb zircon geochronology. Chemical Geology , 238 (3-4) :232–248. DOI:10.1016/j.chemgeo.2006.11.012
[65] Wu FY, Yang JH, Wilde SA, Liu XM, Guo JH, Zhai MG. 2007b. Detrital zircon U-Pb and Hf isotopic constraints on the crustal evolution of North Korea. Precambrian Research , 159 (3-4) :155–177. DOI:10.1016/j.precamres.2007.06.007
[66] Wu FY, Li QL, Yang JH, Kim JN, Han RH. 2016. Crustal growth and evolution of the Rangnim Massif, northern Korean Peninsula. Acta Petrologica Sinica , 32 (10) :2933–2947.
[67] Yang JH, Chung SL, Wilde SA, Wu FY, Chu MF, Lo CH, Fan HR. 2005. Petrogenesis of post-orogenic syenites in the Sulu Orogenic Belt, East China:Geochronological, geochemical and Nd-Sr isotopic evidence. Chemical Geology , 214 (1-2) :99–125. DOI:10.1016/j.chemgeo.2004.08.053
[68] Yengkhom KS, Lee BC, Oh CW, Yi K, Kang JH. 2014. Tectonic and deformation history of the Gyeonggi Massif in and around the Hongcheon area, and its implications in the tectonic evolution of the North China Craton. Precambrian Research , 240 :37–59. DOI:10.1016/j.precamres.2013.10.016
[69] Young DN, Zhao JX, Ellis DJ, McCulloch MT. 1997. Geochemical and Sr-Nd isotopic mapping of source provinces for the Mawson charnockites, east Antarctica:Implications for Proterozoic tectonics and Gondwana reconstruction. Precambrian Research , 86 (1-2) :1–19. DOI:10.1016/S0301-9268(97)00030-2
[70] Zhai MG, Windley BF. 1990. The Archean and Early Proterozoic banded iron formations of North China:Their characteristics, geotectonic relations, chemistry and implications for crustal growth. Precambrian Research , 48 (3) :267–286. DOI:10.1016/0301-9268(90)90012-F
[71] Zhai MG, Ni ZY, Oh CW, Guo JH, Choi SG. 2005. SHRIMP zircon age of a Proterozoic rapakivi granite batholith in the Gyeonggi massif (South Korea) and its geological implications. Geological Magazine , 142 (1) :23–30. DOI:10.1017/S001675680400994X
[72] Zhai MG, Guo JH, Li Z, Chen DZ, Peng P, Li TS, Hou QL, Fan QC. 2007a. Linking the Sulu UHP belt to the Korean Peninsula:Evidence from eclogite, Precambrian basement, and Paleozoic sedimentary basins. Gondwana Research , 12 (4) :388–403. DOI:10.1016/j.gr.2007.02.003
[73] Zhai MG, Guo JH, Peng P, Hu B. 2007b. U-Pb zircon age dating of a rapakivi granite batholith in Rangnim massif, North Korea. Geological Magazine , 144 (3) :547–552. DOI:10.1017/S0016756807003287
[74] Zhai MG, Santosh M. 2011. The early Precambrian odyssey of the North China Craton:A synoptic overview. Gondwana Research , 20 (1) :6–25. DOI:10.1016/j.gr.2011.02.005
[75] Zhai MG, Santosh M. 2013. Metallogeny of the North China Craton:Link with secular changes in the evolving Earth. Gondwana Research , 24 (1) :275–297. DOI:10.1016/j.gr.2013.02.007
[76] Zhai MG, Zhang YB, Zhang XH, Li QL, Peng P, Wu FY, Hou QL, Li TS and Zhao L. 2016. Renewed profile of the Mesozoic magmatism in Korean Peninsula:Regional correlation and broader implication for cratonic destruction in the North China Craton. Science China (Earth Science), doi:10.1007/s11430-016-0107-0
[77] Zhang WY. 1986. Continental-Oceanic Geotectonics of China and Adjacent Areas. Beijing:Science Press , 45 .
[78] Zhang XH, Yuan LL, Xue FH, Zhai MG. 2014. Neoarchean metagabbro and charnockite in the Yinshan block, western North China Craton:Petrogenesis and tectonic implications. Precambrian Research , 255 :563–582. DOI:10.1016/j.precamres.2013.11.003
[79] Zhang XH, Zhang YB, Zhai MG, Wu FY, Hou QL and Yuan LL. 2016. Decoding Neoarchaean to Palaeoproterozoic tectonothermal events in the Rangnim Massif, North Korea:Regional correlation and broader implications. International Geology Review, doi:10.1080/00206814.2016.1198995
[80] Zhang XH, Zhang YB, Yuan LL, Li YS, Choi WJ, Kim H. 2016. Late Permian mafic volcanic rocks in the Hambuk massif, Korean Peninsula:Geochemistry, origin and tectonic implications. Acta Petrologica Sinica , 32 (10) :3070–3082.
[81] Zhang YB, Wu FY, Wilde SA, Zhai MG, Lu XP, Sun DY. 2004. Zircon U-Pb ages and tectonic implications of ‘Early Paleozoic’ granitoids at Yanbian, Jilin Province, Northeast China. The Island Arc , 13 (4) :484–505. DOI:10.1111/iar.2004.13.issue-4
[82] Zhang YB, Wu FY, Zhai MG, Lu XP. 2005. Tectonic setting of the Helong Block:Implications for the northern boundary of the eastern North China Craton. Science in China (Series D) , 48 :1599–1612. DOI:10.1360/02YD0282
[83] Zhang ZM, Zhao GC, Santosh M, Wang JL, Dong X, Shen K. 2010. Late Cretaceous charnockite with adakitic affinities from the Gangdese batholith, southeastern Tibet:Evidence for Neo-Tethyan mid-ocean ridge subduction. Gondwana Research , 17 (4) :615–631. DOI:10.1016/j.gr.2009.10.007
[84] Zhao GC, Sun M, Wilde SA, Li SZ. 2005. Late Archean to Paleoproterozoic evolution of the North China Craton:Key issues revisited. Precambrian Research , 136 (2) :177–2022. DOI:10.1016/j.precamres.2004.10.002
[85] Zhao GC, Cao L, Wilde SA, Sun M, Choe WJ, Li SZ. 2006. Implications based on the first SHRIMP U-Pb zircon dating on Precambrian granitoid rocks in North Korea. Earth and Planetary Science Letters , 251 (3-4) :365–379. DOI:10.1016/j.epsl.2006.09.021
[86] Zhao GC, Cawood PA, Li SZ, Wilde SA, Sun M, Zhang J, He YH, Yin CQ. 2012. Amalgamation of the North China Craton:Key issues and discussion. Precambrian Research , 222-223 :55–76. DOI:10.1016/j.precamres.2012.09.016
[87] Zhao L, Zhou XW, Zhai MG, Santosh M, Ma XD, Shan HX, Cui XH. 2014. Paleoproterozoic tectonic transition from collision to extension in the eastern Cathaysia Block, South China:Evidence from geochemistry, zircon U-Pb geochronology and Nd-Hf isotopes of a granite-charnockite suite in southwestern Zhejiang. Lithos , 184-187 :259–280. DOI:10.1016/j.lithos.2013.11.005
[88] Zhao L, Zhu XY, Zhai MG. 2016. Major advances in the study of the Precambrian geology and metallogenesis of the North China Craton:A review. Acta Geologica Sinica , 90 (4) :1122–1155. DOI:10.1111/acgs.2016.90.issue-4
[89] 白翔, 刘树文, 阎明, 张立飞, 王伟, 郭荣荣, 郭博然.2014. 抚顺南部早前寒武纪变质杂岩的地质事件序列. 岩石学报 , 30 (10) :2905–2924.
[90] 曹林, 朱东.1999. 中朝古大陆东部早前寒武纪变质岩系对比及其演化阶段划分. 世界地质 , 18 (2) :36–46.
[91] 金炳成, 刘永江, 韩国卿, 金才英.2012. 吉林-延吉-朝鲜咸北地区晚古生代沉积特征及其构造演化意义. 吉林大学学报(地球科学版) , 42 (增刊) :296–305.
[92] 金正男, 白龙俊, 韩龙燕. 2006. 前寒武纪地质. 平壤: 金日成综合大学出版社 : 10 -13.
[93] 梁道俊, 刘永江.2009. 前寒武纪早期朝鲜半岛地壳的形成与演化——古陆的形成阶段(Ar-Pt1). 世界地质 , 28 (3) :271–279.
[94] 刘福来, 刘平华, 王舫, 刘超辉, 蔡佳.2015. 胶-辽-吉古元古代造山/活动带巨量变沉积岩系的研究进展. 岩石学报 , 31 (10) :2816–2846.
[95] 路孝平, 吴福元, 林景仟, 孙德有, 张艳斌, 郭春丽.2004. 辽东半岛南部早前寒武纪花岗质岩浆作用的年代学格架. 地质科学 , 39 (1) :123–138.
[96] 邵建波, 李景光, 王洪涛, 陈殿义, 任强.2014. 吉林白山五道羊岔新太古代大型钒钛磁铁矿床地质特征及锆石U-Pb年龄. 中国地质 , 41 (2) :463–483.
[97] 万渝生, 宋彪, 杨淳, 刘敦一.2005. 辽宁抚顺-清原地区太古宙岩石SHRIMP锆石U-Pb年代学及其地质意义. 地质学报 , 79 (1) :78–87.
[98] 吴福元, 葛文春, 孙德有, 林强, 周燕.1997. 吉林南部太古代花岗岩Sm-Nd, Rb-Sr同位素年龄测定. 岩石学报 , 13 (4) :499–506.
[99] 吴福元, 李秋立, 杨正赫, 金正男, 韩龙彦.2016. 朝鲜北部狼林地块构造归属与地壳形成时代. 岩石学报 , 32 (10) :2933–2947.
[100] 张文佑. 1986. 中国及邻区海陆大地构造. 北京: 科学出版社 : 45 -46.
[101] 张晓晖, 张艳斌, 袁玲玲, 李永植, 崔远正, 金宪.2016. 朝鲜半岛咸北地区晚二叠世基性火山岩的地球化学特征:岩石成因与地质意义. 岩石学报 , 32 (10) :3070–3082.