蒙古—鄂霍茨克构造带中段构造变形及动力学特征

黄始琪, 董树文*, 张福勤, 苗来成, 朱明帅

1)中国地质科学院, 北京 100037; 2)中国科学院地质与地球物理研究所, 北京 100029

蒙古—鄂霍茨克构造带中段构造变形及动力学特征

黄始琪1), 董树文1)*, 张福勤2), 苗来成2), 朱明帅2)

1)中国地质科学院, 北京 100037; 2)中国科学院地质与地球物理研究所, 北京 100029

蒙古—鄂霍茨克构造带作为中亚造山带的重要组成部分, 其构造变形和动力学特征一直是地质界关注的问题。沿着该构造带中段, 对5个韧性变形点及1个脆性变形点进行详细解析, 揭示了该构造带变形及动力学特征。B型褶皱、揉皱、A型褶皱、矿物拉伸线理、S-C组构都显示了该构造带明显的NW—SE剪切作用。剪切方向稳定而单一, 未发现多方向变形叠加现象, 可能指示了蒙古—鄂霍茨克构造带的形成过程为一期主要的俯冲碰撞或多期同向的俯冲碰撞。对蒙古—鄂霍茨克构造带形成时间和动力学背景进行了讨论, 认为该构造带主要形成于中晚侏罗世—早白垩世东亚多向汇聚动力学背景之下。对构造带内地质点mg6脆性断层面上滑动矢量进行了统计和古应力场反演, 得出两期古构造应力场, 一期为NW—SE挤压, 一期为近E—W挤压。NW—SE挤压应力场可能对应了中晚侏罗世—白垩纪古太平洋板块向西俯冲对中亚地区的远程影响; 而近 E—W 向挤压可能反映了早新生代印度—欧亚板块碰撞对中亚地区的远程效应。

蒙古—鄂霍茨克构造带; 韧性变形; 脆性变形; 古应力场; 东亚多向汇聚; 蒙古

Key words:Mongolia-Okhotsk collisional belt; ductile deformation; brittle deformation; stress field; East Asian multi-direction convergence; Mongolian

中亚造山带位于西伯利亚板块与塔里木和华北板块之间, 主要由华北板块和西伯利亚板块的俯冲增生所形成, 是世界上最大的增生型造山带(Sengör et al., 1993; Wickham et al., 1996; Jahn et al., 2000a, b; Kovalenko et al., 2004; Xiao et al., 2008, 2009a, b)。蒙古—鄂霍茨克构造带是中亚造山带的重要组成部分(图 1), 在东亚大陆形成演化的历史上占有极为重要的地位(李锦轶等, 2009)。根据岩石建造, 赵越等(1994)认为该构造带是华北板块和西伯利亚板块之间的最后缝合带。蒙古—鄂霍茨克构造带主要分布在东经96°—130°, 北纬46°—58°之间的俄罗斯和蒙古境内, 西起蒙古中部的杭盖山脉, 东至鄂霍茨克海的乌达海湾, 总体呈北东—南西走向, 长约3000 km, 宽约300 km, 北部为西伯利亚板块及其增生边缘, 南部为中朝—蒙古板块及其以北的造山带与地块镶嵌构造区, 东部为太平洋板块。蒙古—鄂霍茨克洋俯冲时间一直存在争议, Sengör等(1993)认为在埃迪卡拉纪—晚二叠世; Parfenov等(2003)认为在泥盆纪—早三叠世; Gordienko等(2010)和Bussien等(2011)认为在泥盆纪—二叠纪; Metelkin等(2010)认为在晚石炭世—晚侏罗世; Zhao等(1990)、Enkin等(1992)、Kuzmin等(1996)以及 Zorin(1999)认为在早二叠世—中侏罗世; Zonenshain等(1990)认为在三叠纪—晚侏罗世。蒙古—鄂霍茨克洋的最终俯冲关闭时间也存在争议, Zonenshain等(1990)认为西侧关闭时间为三叠纪—晚侏罗世; Zorin(1999)和Parfenov等(1999)认为发生在中晚侏罗世。许多学者认为东段的封闭时间更晚, 应该在晚侏罗世—早白垩世(Sengor et al., 1996; Yakubchuk et al., 1999; Kravchinsky et al., 2002a; Cogné et al., 2005; 李锦轶, 1998, 2013)。尽管蒙古—鄂霍茨克构造的开启和最终闭合时间存在争议, 而蒙古—鄂霍茨克洋两侧板块的碰撞是一个自西向东的顺时间旋转碰撞得到地质学者的普遍认同(Zorin, 1999)。这种碰撞过程有的学者认为主要是晚元古代—石炭纪的一次单阶段俯冲碰撞(Sengör et al., 1993, 1996); 有的学者则认为是多阶段俯冲碰撞(Badarch et al., 2002; Filippova et al., 2001; Kröner et al., 2005, 2007; Windley et al., 2007; Zorin et al., 2007)。Donskaya等(2013)认为石炭纪蒙古—鄂霍茨克洋壳高角度俯冲, 导致褶皱变形, 双重推覆构造,及最后地壳加厚。正常角度的俯冲发生在晚二叠世到晚三叠世, 导致大量侵入岩和火山岩的产出。碰撞过程的不同, 对应的岩石变形和反映的动力学特征也不同, 通过对露头尺度岩石的变形解析有助于揭开真实的地质演化过程。而碰撞之后该构造带是否受后期其它区域应力作用影响, 可以通过脆性断层的古应力场反演来加以解析。本文基于野外岩石脆韧性变形数据的收集和分析, 对蒙古—鄂霍次克构造带中段岩石变形及其对应的动力学特征做了基本分析, 以揭示蒙古—鄂霍茨克构造带碰撞变形及动力学过程。

图1 蒙古—鄂霍茨克构造带及其邻区构造简图(据Donskaya et al., 2013修改)Fig. 1 Simplified tectonic map of the Mongolia–Okhotsk collisional belt and its adjacent areas (modified after Donskaya et al., 2013)

蒙古—鄂霍茨克构造带中段主要由杭盖—肯特区、奥伦岛弧区和南部的阿穆尔区组成(图1)。杭盖—肯特区主要为古生代浊积岩盆地, 而其具体时代及属性存在一定争议。Minjin等(2006)认为盆地内乌兰巴托附近存在中—晚泥盆世混杂岩; 而有的学者认为盆地内泥盆纪增生杂岩与早古生代增生杂岩伴生, 石炭纪浊积岩不整合于下伏增生杂岩之上(Dorjsurend et al., 2006); Tomas等(2008)对杭盖—肯特盆地古生代地层的碎屑锆石研究, 证明该浊积岩盆地形成于 345 Ma后的早石炭世晚期, 碎屑锆石还揭示了浊积盆地与下伏前早石炭世地质体间的广泛不整合。奥伦岛弧区超过 1000 m厚的泥盆系—石炭系钠质玄武岩、碧玉、超镁铁质岩覆于前寒武纪的结晶基底上, 石炭系之上是二叠纪到三叠纪的陆源磨拉石建造(莫申国等, 2005)。本文研究区域主要在蒙古境内阿穆尔板块。阿穆尔板块是前苏联学者Zonenshain和Savostin于1981年首次提出的, 主要用于解释从贝加尔裂谷以东沿斯坦诺夫山地的地震活动条带(Zonenshain et al., 1981)。阿穆尔板块的西部边界为贝加尔裂谷, 向北经过斯坦诺夫山地,然后向东, 沿日本岛以西一系列的正断层南下, 在日本本州中部与南海地槽相连, 而后向西经朝鲜半岛南端由渤海进入中国, 经山西地堑北部、鄂尔多斯北端向西北与贝加尔裂谷相接, 形成一个覆盖中国东北及华北部分地区、朝鲜半岛、日本西南部、俄罗斯东南部及蒙古西部的巨大构造单元(许厚泽等, 2004)。阿穆尔地区主要为元古代基底及石炭纪至二叠纪的火成岩带(Denise et al., 2011)。据Ren等(2013)和任纪舜等(2013)亚洲地质编图结果显示,沿着蒙古—鄂霍茨克构造带广泛发育岩浆岩, 西段及中段主要为石炭纪—二叠纪花岗岩和花岗闪长岩, 往东岩浆岩年龄逐渐变新, 出现侏罗纪花岗岩和花岗闪长岩。

1 韧性变形及动力学特征

由南西往北东, 沿着蒙古—鄂霍茨克构造带中段, 分析了 5个重要韧性变形点的形态学和动力学特征。显示明显的NW—SE剪切作用。mg7位于东经 110°12′12″, 北纬 47°23′43″, 蒙古木伦市西南,岩性为泥盆纪(Bussien et al., 2011)灰黑色变泥质岩,绿片岩相, 原岩可能为凝灰质砂岩。发生明显的断滑式褶皱, 反映NW—SE剪切作用(图2)。mg8与mg7相邻, 位于东经 110°13′47″, 北纬 47°23′39″。该处泥盆纪变泥岩内侵入角闪辉长岩脉, 岩脉产状为345°/80°, 宽约3 m。岩脉内长石发生强的韧性变形, 形成揉皱和 A型褶皱, 指示 NW—SE剪切(图3)。该点亦见蛇纹岩, 岩石片理化明显, 且片理发生褶皱变形, 指示NW—SE剪切作用(图4)。mg11位于东经111°45′41″, 北纬48°47′11″, 蒙古乌兰河东。岩性为泥盆纪(Bussien et al., 2011)云母石英片岩,岩内石英脉发生揉皱, 石香肠构造, 及 A 型褶皱,指示NW—SE剪切作用(图5, 6, 7)。mg14位于东经112°53′19″, 北纬 49°22′20″, 巴彦乌拉北, 蒙古—鄂霍茨克构造带北部, 该处为二叠纪(Bussien et al., 2011)云母石英片岩, 片理化明显, 暗色矿物形成拉伸线理, 片理总体产状为: 325°/19°, 线理总体产状为: 325°/20°。S-C组构反映NW—SE剪切作用(表1, 图7)。mg16位于mg14北侧, 东经112°52°11″, 北纬 49°25′33″, 蒙古与俄罗斯交界处, 紧邻蒙古—鄂霍茨克缝合带。岩性为二叠纪(Bussien et al., 2011)黑云斜长角闪片岩, 糜棱岩化。面理总体产状为: 331°/24°, 线理产状为: 321°/18°。S-C组构, 反映NW—SE剪切作用(表2, 图8)。

图2 点mg7 B型断滑褶皱(位置见图1)Fig. 2 B-fold of schist at Site mg7(see Fig. 1 for the location)

图3 点mg8辉长岩脉内长石脉发生柔皱(位置见图1)Fig. 3 Crumple structure of feldspar veins in the gabbro dike at Site mg8 (see Fig. 1 for the location)

2 脆性变形及动力学特征

岩石韧性变形后, 抬升至较浅地表, 受区域应力作用, 易发生脆性变形而改造原有韧性变形(孟宪刚等, 2001)。通过统计分析脆性断层面上滑动矢量的运动特征, 反演古构造应力场。本文使用斯诺维尼亚Žalohar等(2007)开发的应力场反演软件, 基本原理为安德森模式和库伦摩尔破裂准则。

图4 点mg8蛇纹岩发生柔皱(位置见图1)Fig. 4 Crumple structure in serpentinite at Site mg8 (see Fig. 1 for the location)

图5 点mg11片岩内A型褶皱(位置见图1)Fig. 5 A style fold in schist at Site mg11(see Fig. 1 for the location)

图6 点mg11片岩内长英质脉发生柔皱(位置见图1)Fig. 6 Crumple structure of felsic veins in schist at Site mg11 (see Fig. 1 for the location)

图7 点mg11片岩内过渡型A型褶皱(位置见图1)Fig. 7 Transitional A-fold of schist at Site mg11 (see Fig. 1 for the location)

表1 点mg14面理及线理统计结果Table 1 Statistics of foliations and lineations at Site mg14

图8 点mg14韧性变形(位置见图1)Fig. 8 Ductile deformation at Site mg14 (see Fig. 1 for the location)

图9 点mg16韧性变形(位置见图1)Fig. 9 Ductile deformation at Site mg16 (see Fig. 1 for the location)

mg6位于东经 110°07′26″, 北纬 47°23′25″, 蒙古木伦市西南, 蒙古—鄂霍茨克构造带中段南部,该处泥盆纪地层内倾入后期辉长岩, 并发生糜棱岩化, 后期脆性断层切割辉长糜棱岩。对断层面上滑动矢量统计分析以及古应力场反演, 得出一期 NW—SE挤压古应力场和一期近E—W挤压古应力场。NW—SE应力场最大主应力轴产状为309°/2°, 中间主应力轴和最小主应力轴产状分别为 40°/24°和215°/66°(表3, 图10)。NE—SW向挤压应力场最大主应力轴产状为 268°/17°, 中间主应力轴和最小主应力轴产状分别为5°/24°和145°/60°(表4, 图11)。

3 讨论与构造意义

蒙古—鄂霍茨克构造带的形成是经历了一次主要俯冲碰撞还是经历多次俯冲碰撞一直存在争议(Sengör et al., 1993, 1996; Badarch et al., 2002; Filippova et al., 2001; Kröner et al., 2005, 2007; Windley et al., 2007; Zorin et al., 2007; Donskaya et al., 2013)。如果是经历了多次大规模方向不同的俯冲碰撞, 则岩石韧性变形可能会体现出多期构造作用的叠加现象, 如多期拉伸线理叠加, 多方向 A型褶皱叠加等, 而如果是同方向的多期俯冲碰撞, 原有的韧性变形只是被后期构造作用加强, 不易识别多阶段的叠加现象。沿着蒙古—鄂霍茨克构造带所分析的mg7、mg8、mg11、mg14、mg16五个韧性变形点, 皆显示一致的NW—SE剪切作用。mg7、mg8所见的B型和A型褶皱未见多方向叠加现象, mg14、mg16面理上并未见多方向线理叠加现象, 因此, 推断蒙古—鄂霍茨克构造带是一次主要俯冲碰撞或多期同方向俯冲碰撞的产物。

表3 点mg6反映NW—SE挤压应力场断层滑动矢量统计Table 3 Results of fault–slip analysis and stress orientations at Site mg6 defining a compressional regime with NW–SE compression

表4 点mg6反映近E—W挤压应力场断层滑动矢量统计Table 4 Results of fault-slip analysis and stress orientations at Site mg6 defining a compressional regime with E–W compression

图10 mg6 NW—SE挤压应力场及应力摩尔圆图析(位置见图1)Fig. 10 Fault-slip data and computed stress axis of NW–SE compression and its stress Moore circle analysis at Site mg6 (see Fig. 1 for the location)

图11 mg6近E—W挤压应力场及应力摩尔圆图析(位置见图1)Fig. 11 Fault-slip data and computed stress axis of E–W compression and its stress Moore circle analysis at Site mg6 (see Fig. 1 for the location)

蒙古—鄂霍茨克洋东段最终闭合时间一直持续到晚侏罗世—白垩纪, 对应了中国的燕山运动,董树文等(2000, 2007, 2008)和Dong等(2013)认为燕山运动不仅仅局限于中国东部地区, 而是一个全球范围的大构造事件, 其影响远远超出中国东部的范围, 是东亚多板块的多向汇聚事件。约起始于170 Ma, 多板块几乎同时向东亚地区发生俯冲或推覆碰撞, 在克拉通和刚性盆地周缘形成环形造山带,如四川盆地和鄂尔多斯盆地周边的造山带。受此构造事件影响, 西伯利亚克拉通周缘也形成大规模环形山系。西伯利亚板块向南运动逆冲到华北—蒙古板块基底和被动大陆边缘沉积地层之上, 以及导致蒙古—鄂霍茨克构造带北西侧结晶基底推覆于中侏罗世含煤沉积岩之上(Zorin, 1999), 意味着该构造带形成的主要阶段为中晚侏罗世。该逆冲推覆系统构成蒙古—鄂霍茨克构造带主枝, 据上地壳地球物理图像, 蒙古—鄂霍茨克构造带杭盖地区水平位移量为150 km, 肯特地区为100 km。奥伦岛弧在碰撞前位于西伯利亚板块和华北蒙古板块之间, 碰撞时脱离其基底推覆于华北—蒙古板块之上, 其水平位移量为200 km(Zorin, 1999)。西伯利亚板块向南运动与华北—蒙古板块碰撞的同时, 侏罗纪末期, 北美洲板块以及科利马—奥莫隆复合地块向西运动与其碰撞形成近南北走向的维尔霍扬斯克冲断褶皱带(Vladimir et al., 2003)。维尔霍扬斯克褶皱带内古生代到早中生代几个深水沉积盆地在晚中生代板块碰撞作用下发生强烈的褶皱变形, 也说明维尔霍扬斯克冲断褶皱带主要形成于晚中生代(Eugene et al., 1986)。另外, 蒙古—鄂霍茨克构造带两侧大量发育130 Ma碰撞后的伸展盆地(Yannick et al., 2013), 也意味着晚侏罗世—早白垩世在该区发生了强烈的碰撞挤压事件。

越来越多的事实证明发生在中晚侏罗世的东亚多向汇聚构造事件影响范围十分广泛, 造成东亚地区强烈构造变形, 其背后有着深刻的地球动力学背景与动力来源(董树文等, 2008)。自侏罗纪以来,东亚地区大量岩石圈物质俯冲到地幔之中, 是地球上俯冲岩石圈物质最大量的地区(Maruyama et al., 2007)。而华北与扬子陆块碰撞造山作用, 使得中国东部岩石圈厚度曾经达到150~200 km, 可能是东亚汇聚的先兆(董树文等, 2008)。随后发生的东亚和中国东部巨厚岩石圈的垮塌、拆沉和断离, 导致了超高压岩石的折返, 软流圈物质侧向补偿, 牵引了太平洋板块向西俯冲, 印度洋板块向 NE俯冲, 西伯利亚陆块与华北陆块碰撞(董树文等, 2008), 甚至北美洲板块向西与西伯利亚板块碰撞(Vladimir et al., 2003), 形成一个多板块在中晚侏罗世同时向东亚地区汇聚的格局。

mg6通过脆性断层反演出一期NW—SE挤压应力场, 很可能对应了晚侏罗世到早白垩世古太平洋俯冲对中亚造山带的远程影响。印度—欧亚板块的碰撞及之后的合并对亚洲新生代以来的地质、构造、地球动力学, 甚至气候都产生了巨大影响(Johan et al., 2007; Tapponnier et al., 1982, 2001; Yin, 2006; Yin et al., 2000; 张岳桥等, 2012)。中亚造山带虽远离印度—欧亚板块, 其晚期的再活动也明显受到这次强烈构造活动的远程影响(Molnar et al., 1975, 1977; Tapponnier et al., 1979; Peltzer et al., 1988)。研究区mg6通过脆性断层反演的一期近 E—W 挤压, 很可能反映了印度—欧亚板块碰撞的远程效应及原有蒙古—鄂霍茨克构造带边界限制作用的联合影响。

4 结论

蒙古—鄂霍茨克构造带作为中亚造山带的重要组成部分, 其变形和动力学特征一直是地质界关注的问题, 沿着该构造带中段, 对该构造带进行韧性和脆性变形分析, 主要得出以下结论:

1)对蒙古—鄂霍茨克构造带5个韧性变点进行了形态学动力学解析, 显示NW—SE剪切作用。剪切方向单一, 未发现多方向的变形叠加现象, 可能指示了蒙古—鄂霍茨克构造带的形成经历了一期强烈的俯冲碰撞或多期同向的俯冲碰撞作用。

2)对蒙古—鄂霍茨克构造带形成时间和动力学背景进行了讨论。该构造带主要形成于中晚侏罗世—早白垩世东亚多向汇聚动力学背景之下。

3)对mg6脆性断层滑动矢量进行了统计和古应力场反演, 得出两期古构造应力场, 一期为 NW—SE挤压, 一期为近E—W挤压。NW—SE挤压应力场可能对应了晚侏罗世古太平洋板块对中亚地区的远程影响, 而近E—W向挤压可能反映了早新生代印度—欧亚板块碰撞对中亚地区的远程效应。

董树文, 吴锡浩, 吴珍汉, 邓晋福, 高锐, 王成善. 2000. 论东亚大陆的构造翘变[J]. 地质论评, 46(1): 8-13.

董树文, 张岳桥, 陈宣华, 龙长兴, 王涛, 杨振宇, 胡健民. 2008.晚侏罗世东亚多向汇聚构造体系的形成与变形特征[J]. 地球学报, 29(3): 306-317.董树文, 张岳桥, 龙长兴, 杨振宇, 季强, 王涛, 胡建民, 陈宣华. 2007. 中国侏罗纪构造变革与燕山运动新诠释[J]. 地质学报, 81(11): 1449-1461.

李锦轶, 曲军峰, 张进, 刘建峰, 许文良, 张拴宏, 郭瑞清, 朱志新,李亚萍, 李永飞, 王涛, 徐学义, 李智佩, 柳永清, 孙立新, 简平, 张昱, 王励嘉, 彭树华, 冯乾文, 王煜, 王洪波, 赵西西. 2013. 中国北方造山区显生宙地质历史重建与成矿地质背景研究进展[J]. 地质通报, 32(2-3): 207-219.

李锦轶, 张进, 杨天南, 李亚萍, 孙桂华, 朱志新, 王励嘉. 2009．北亚造山区南部及其毗邻地区地壳构造分区与构造演化[J]. 吉林大学学报(地球科学版), 39(4): 584-605.

李锦轶. 1998. 中国东北及邻区若干地质构造问题的新认识[J].地质论评, 44(4): 339-347.

莫申国, 韩美莲, 李锦轶. 2005. 蒙古-鄂霍茨克造山带的组成及造山过程[J]. 山东科技大学学报(自然科学版), 24(3): 50-52, 64.

任纪舜, 牛宝贵, 王军, 和政军, 金小赤, 谢良珍, 赵磊, 刘仁燕,江小均, 李舢, 杨付岭. 2013. 1:500万国际亚洲地质图[J]. 地球学报, 34(1): 24-30.

许厚泽, 熊熊. 2004. 东北亚大陆地壳运动的GPS研究[J]. 大地测量与地球动力学, 24(4): 1-6.

盂宪刚, 冯向阳, 邵兆刚, 杨美玲, 朱大岗, 王建平. 2001. 雪峰山中段金矿区主要断裂带构造特征及其动力学[J]. 地球学报, 22(2): 117-122.

张岳桥, 董树文, 李建华, 崔建军, 施炜, 苏金宝, 李勇. 2012.华南中生代大地构造研究新进展[J]. 地球学报, 33(3): 257-279.

赵越, 杨振宇, 马醒华. 1994. 东亚大地构造发展的重要转折[J].

地质科学, 29(2): 105-114.

References:

BADARCH G, CUNNINGHAM W D, WINDLEY B F. 2002. A new terrane subdivision for Mongolia: implications for the Phanerozoic crustal growth of Central Asia[J]. Journal of Asian Earth Sciences, 21: 87-110.

BUSSIEN D, GOMBOJAV N, WINKLER W, QUADT A. 2011. The Mongol-Okhotsk Belt in Mongolia – an appraisal of the geodynamic development by the study of sandstone provenance and detrital zircons[J]. Tectonophysics, 510: 132-150.

COGNÉ J P, KRAVCHINSKY V A, HALIM N, HANKARD F. 2005. Late Jurassic – early Cretaceous closure of the Mongol-Okhotsk Ocean demonstrated by new Mesozoic palaeomagnetic results from the Trans-Baikal area (SE Siberia)[J]. Geophysical Journal International, 63: 813-832.

DONG S W, GAO R, YIN A, GUO TONGLOU, ZHANG Y Q, HU J M, LI J Y, SHI W, LI Q S. 2013. What drove continued continent-continent convergence after ocean closure? Insights from high-resolution seismic-reflection profiling across the Daba Shan in central China[J]. Geology, 41: 671-674.

DONG Shu-wen, WU Xi-hao, WU Zhen-han, DENG Jin-fu, GAO Rui, WANG Cheng-shan. 2000. On Tectonic Seesawing of the East Asia Continent—Global implication of the Yanshanian Movement[J]. Geological Review, 46(1): 8-13(in Chinese with English abstract).

DONG Shu-wen, ZHANG Yue-qiao, CHEN Xuan-hua, LONG Chang-xing, WANG Tao, YANG Zhen-yu, HU Jian-min. 2008. The Formation and Deformational Characteristics of East Asia Multi-Direction Convergent Tectonic System in Late Jurassic[J]. Acta Geoscientica Sinica, 29(3): 306-317(in Chinese with English abstract).

DONG Shu-wen, ZHANG Yue-qiao, LONG Chang-xing, YANG Zhen-yu, JI Qiang, WANG Tao, HU Jian-min, CHEN Xuan-hua. 2007. Jurassic tectonic evolution in China and new interpretation of the Yanshan movements[J]. Acta Geologica Sinica, 81(11): 1449-1461(in Chinese with English abstract).

DONSKAYA D P, GLADKOCHUB A M, MAZUKABZOY A V I. 2013. Late Paleozoic – Mesozoic subduction-related magmatism at the southern margin of the Siberian continent and the 150 million-year history of the Mongol-Okhotsk Ocean[J]. Journal of Asian Earth Sciences, 62(30): 79-97.

DORJSUREN B, BUJINLKHAM B, MINJIN C, TSUKADA K. 2006. Geological setting of the Ulaanbaatar terrane in the Hangay –Henteyzone of the Devonian accretionary complex, Central Asian orogenic belt[EB/OL]. [2013-02-03]. http:// www.igcp.itu.edu. tr/Publications/Dorjsuren_06.pdf.

ENKIN R J, YANG Z, CHEN Y, COURTILLOT V. 1992. Paleomagnetic constraints on the geodynamic history of major blocks of China from the Permian to the Present[J]. Journal Geophysical Research, 97(B10): 13953-13989.

EUGENE V A, Michael A B. 1986. Mechanisms of formation of deep basins on continental crust in the Verkhoyansk fold belt; miogeosynclines and cratonic basins)[J]. Tectonophysics, 122(3-4): 217-245.

FILIPPOYA I B, BUSH V A, DIDENKO A N. 2001. Middle Paleozoic subduction belts: the leading factor in the formation of the Central Asian fold-and-thrust belt[J]. Russian Journal of Earth Sciences, 3: 405-426.

GORDIENKO I V, BULGATOV A N, RUZHENTSEY S V, MININA O R, KLIMUK V S, VETLUZHSKIKH L I, NEKRASOV G E, LASTOCHIN N I, SITNIKOVA V S, METELKIN D V, GONEGER T A, LEPEKHINA E N. 2010. The Late Riphean–Paleozoic history of the Uda–Vitim island arc system in the Transbaikalian sector of the Paleoasian ocean[J]. Russian Geology and Geophysics, 51: 461-481.

JAHN B M, WU F Y, CHEN B. 2000a. Granitoids of the Central Asian Orogenic Belt and continental growth in the Phanerozoic[J]. Trans-actions Royal Society of Edinburgh: Earth Sciences, 91: 181-193.

JAHN B M, WU F Y, HONG D W. 2000b. Massive granitoids genera-tion in Central Asia: Nd isotopic evidence and implication for cont-inental growth in the Phanerozoic[J]. Episodes, 23(2): 82-92.

JOHAN D G, MICHAEL M B, PETER V D H. 2007. Distant effects of India–Eurasia convergence and Mesozoic intracontinental deformation in Central Asia: Constraints from apatitefission-track thermochronology[J]. Journal of Asian Earth Sciences, 29(2-3): 188-204.

KOVALENKO V I, YARMOLYUK V V, KOVACH V P, KOTOVE A B, KOZAKOV I K, SALNIKOVA E B, LARIN A M. 2004. Isotope provinces, mechanisms of generation and sources of the continental crust in the Central Asian Mobile Belt: geological and isotopic ev-idence[J]. Journal of Asian Earth Sciences, 23: 605-627.

KRAVCHINSKY V A, COGNE J P, HARBERT W P, KUZMIN M I. 2002a. Evolution of the Mongol-Okhotsk Ocean as constrained by new palaeomagnetic data from the Mongol-Okhotsk suture zone, Siberia[J]. Geophysical Journal International, 148: 34-57.

KRÖNER A, WINDLEY B F, BADARCH G, TOMURTOGOO O, HEGNER E, JAHN B M, GRUSCHA S, KHAIN E V, DEMOUX A, WINGATE M T D. 2007. Accretionary growth and crust-formation in the Central Asian Orogenic Belt and comparison with the Arabian–Nubian shield[J]. Geological Society of America Memoir, 200: 181-209.

KRÖNER A, WINDLEY B F, BADARCH G, TOMURTOGOO O, HEGNER E, LIU D Y, WINGATE M T D. 2005. Accretionary growth in the Central Asian Orogenic Belt of Mongolia during the Neoproterozoic and Palaeozoic and comparison with the Arabian–Nubian Shield and the present Southwest Pacific[J]. Geophysical Research Abstracts, 7, SRef-ID: 1607-7962/gra/ EGU05-A-06650.

KUZMIN M I, KRAVCHINSKY V A. 1996. Preliminary paleomagnetic data on the Mongolia–Okhotsk fold belt[J]. Russian Geology and Geophysics, 37 (1): 54-62.

LI Jin-yi, QU Jun-feng, ZHANG Jin, LIU Jian-feng, XU Wen-liang, ZHANG Shuan-hong, GUO Rui-qing, ZHU Zhi-xin, LI Ya-ping, LI Yong-fei, WANG Tao, XU Xue-yi, LI Zhi-pei, LIU Yong-qing, SUN Li-xin, JIAN Ping, ZHANG Yu, WANG Li-jia, PENG Shu-hua, FENG Qian-wen, WANG Yu, WANG Hong-bo, ZHAO Xi-xi. 2013. New Developments on the Reconstruction of Phanerozoic Geological History and Research of Metallogenic Geological Settings of the Northern China Orogenic Region[J]. Geological Bulletin of China, 32(2-3): 207-219(in Chinese with English abstract).

LI Jin-yi, ZHANG Jin, YANG Tian-nan, LI Ya-ping, SUN Gui-hua, ZHU Zhi-xin, WANG Li-jia. 2009. Crustal Tectonic Division and Evolution of the Southern Part of the North Asian Orogenic Region and Its Adjacent Areas[J]. Journal of Jilin University(Earth Science Edition), 39(4): 584-605(in Chinese with English abstract).

LI Jin-yi. 1998. Some New Ideas on Tectonics of NE China and Its Neighboring Areas[J]. Geological Review, 44(4): 310-347(in Chinese with English abstract).

MARUYAMA S, SANTOSH M, ZHAO D. 2007. Superplume, super-continent, and post-perovskite: Mantle dynamics and ant-i plate tec-tonics on the Core-Mantle Boundary[J]. GondwanaResearch, 11: 7-37.

MENG Xian-gang, FENG Xiang-yang, SHAO Zhao-gang, YANG Mei-ling, ZHU Da-gang, WANG Jian-ping. 2001. Structural Features and Dynamics of Major Fault Belts in Gold Deposits of Middle Xuefeng Mountain[J]. Acta Geoscientica Sinica, 22(2): 117-122(in Chinese with English abstract).

METELKIN D V, VEMIKOVSKY V A, KAZANSKY Y A, WINGATE M T D. 2010. Late Mesozoic tectonics of Central Asia based on paleomagnetic evidence[J]. Gondwana Research, 18: 400-419.

MINJIN C, TOMURTOGOO O, DORJSUREN B. 2006. Devonian-Carboniferous accretionary complex of the Ulaanbaatar terrane, Excursiong aroud Ulaanbaatar[EB/OL]. [2013-02-14]. http://www. igcp.itu.edu.tr/Publications/MinjinGuide1_06.pdf.

MO Shen-guo, HAN Mei-lian, LI Jin-yi. 2005. Compositions and orogenic processes of Mongolia-Okhotsk orogen[J]. Journal of Shandong University of Science and Technology (Natural-Science), 24(3): 50-52, 64(in Chinese with English abstract).

MOLNAR P, TAPPONNIER P. 1975. Cenozoic tectonics of Asia: effects of a continental collision[J]. Science, 189: 419-426.

MOLNAR P, TAPPONNIER P. 1977. Relation of the tectonics of eastern China to the India–Eurasia collision: application of slip-line field theory to large-scale continental tectonics[J]. Geology, 5: 212-216.

PARFENOV L M, BERZIN N A, KHANCHUK A I, BADRACH G, BELICHENKO V G, BULGATOV A N, DRIL S I, KIRILLOVA G L, KUZ`MIN M I, NOCKLEBERG W J, PROKOP`EV A V, TIMOFEEV, V F, TOMURTOGOO O, YAB H. 2003. A model for the formation of orogenic belts in Central and Northeast Asia[J]. Tikhookeanskaya Geologiya, 22(6): 7-41.

PARFENOV L M, POPEKO L I, TOMURTOGOO O. 1999. The Problems of tectonics of the Mongol-Okhotsk orogenic belt[J]. Geology of the Pacific Ocean, 18(5): 24-43.

PELTZER G. TAPPONNIER P. 1988. Formation and evolution of strike-slip faults, rifts, and basins during the India-Asia collision: an experimental approach[J]. Journal of Geophysical Research, 93: 15085-15117.

REN J S, NIU B G, WANG J, JIN X C, ZHAO L, LIU R Y. 2013. Advances in research of Asian geology—A summary of 1:5M International Geological Map of Asia project[J]. Journal of Asian Earth Sciences, 72: 3-11.

REN Ji-shun, NIU Bao-gui, WANG Jun, HE Zheng-jun, JIN Xiao-chi, XIE Liang-zhen, ZHAO Lei, LIU Ren-yan, JIANG Xiao-jun, LI Shan, YANG Fu-ling. 2013. 1:5 Million International Geological Map of Asia[J]. Acta Geoscientica Sinica, 34(1): 24-30(in Chinese with English abstract).

SENGÖR A M C, NATAL`IN B A, BURTMAN V S. 1993. Evolution of the Altaid tectonic collage and Paleozoic crustal growth in Eurasia[J]. Nature, 364: 299-307.

SENGÖR A M C, NATAL`IN B A. 1996. Palaeotectonics of Asia: fragments of a synthesis//YIN A, HARRISON T M. The Tectonic Evolution of Asia[M]. Cambridge: Cambridge Univer-sity Press: 486-640.

TAPPONNIER P, MOLNAR P. 1979. Active faulting and Cenozoic tectonics of the Tien Shan, Mongolia, and Baykal regions[J]. Journal of Geophysical Research, 84: 3425-3459.

TAPPONNIER P, PELTZER G, LE DAIN A Y, ARMIJO R, COBBOLD P. 1982. Propagating extrusion tectonics in Asia: new insights from simple experiments with plasticine[J]. Geology, 10: 611-616.

TAPPONNIER, P, XU Z Q, ROGER F, MEYER B, AMAUD N, WITTLINGER G, YANG J S. 2001. Geology-oblique stepwise rise and growth of the Tibet Plateau[J]. Science, 294: 1671-1677.

THOMAS K K, YIN A, BATULZII D, GEORGE E G, ANGELA E R. 2008. Detrital-zircon geochronology of Paleozoic sedimentary rocks in the Hangay–Hentey basin, north-central Mongolia: Implications for the tectonic evolution of the Mongol–Okhotsk Ocean in central Asia[J]. Tectonophysics, 451(1-4): 290-311.

VLADIMIR S O. 2003. Tectonic evolution of the Mesozoic Verkhoyansk–Kolyma belt (NE Asia)[J]. Tectonophysics, 365: 45-76.

WICKHAM S M, ALBERTS A D, ZANVILEVICH A N, LITVINOVSKY B A, BINDEMAN I N, SCHUBLE E A. 1996. A stable isotope study of anaorogenic magmatism in East Central Asia[J]. J. Petrol., 37: 1063-1095.

WINDLEY B F, ALEXEIEV D, XIAO W, KRÖNER A, BADERCH G. 2007. Tectonic models for accretion of the Central Asian Orogenic Belt[J]. Journal of the Geological Society of London, 164: 31-47.

XIAO W J, HAN C M, YUAN C, SUN M, LIN S F, CHEN H L, LI Z L, LI J L, SUN S. 2008. Middle Cambrian to Permian subduction-related accretionary orogenesis of North Xinjiang, NW China: implications for the tectonic evolution of Central Asia[J]. Journal of Asian Earth Sciences, 32: 102-117.

XIAO W J, WINDLEY B F, HUANG B C, HAN C M, YUAN C, CHEN H L, SUN M, SUN S, LI J Y. 2009b. End-Permian to mid-Triassic termination of the accretionary processes of the south-ern Altaids: implications for the geodynamic evolution, Phanerozoic continental growth, and metallogeny of Central Asia[J]. Int. J. Earth Sci., 98(6): 1189-1217.

XIAO W J, WINDLEY B F, YUAN C, SUN M, HAN C M, LIN S F, CHEN H L, YAN Q R, LIU D Y, QIN K Z, LI J Y, SUN S. 2009a. Paleozoic multiple sub-duction-accretion processes of the southern Altaids[J]. American Journal of Science, 309: 221-270.

XU Hou-ze, XIONG Xiong. 2004. Study ofcontinental crustmove-ment of Northeast Asia with GPS[J]. Journal of Geodesy and Geodynamics, 24(4): 1-6(in Chinese with English abstract). YAKUBCHUK A S, EDWARDS A C. 1999. Auriferous Palaeozoic accretionary terranes within the Mongol-Okhotsk suture zone, Russian Far East[C]//WEBER G. Proceedings Pacrim’99. Australasian Institute of Mining and Metallurgy, Publications Series 4/99: 347-358.

YANNICK D, GILLES R, ALAIN C, PATRICK L, DENIS G. 2013. Timing of exhumation of the Ereendavaa metamorphic core complex (north-eastern Mongolia) – U-Pb and40Ar/39Ar constraints[J]. Journal of Asian Earth Sciences, 62: 98-116.

YIN A, HARRISON T M. 2000. Geologic evolution of the Himalayan–Tibetan orogen[J]. Annual Review of Earth and Planetary Sciences, 28: 211-280.

YIN A. 2006. Cenozoic tectonic evolution of the Himalayan orogen as constrained by along-strike variation of structural geometry, exhumation history, and foreland sedimentation[J]. Earth-Science Reviews, 76: 1-131.

ŽALOHAR J, VRABEC M. 2007. Paleostress analysis of heterogeneous fault-slip data: the Gauss method[J]. Journal of Structural Geology, 29: 1798-1810.

ZHANG Yue-qiao, DONG Shu-wen, LI Jian-hua, CUI Jian-jun, SHI Wei, SU Jin-bao, LI Yong. 2013. The New Progress in the Study of Mesozoic Tectonics of South China[J]. Acta Geoscientica Sinica, 33(3): 257-279(in Chinese with English abstract).

ZHAO X, COE R S, ZHOU Y, WU H, WANG J. 1990. New paleomagnetic results from Northern China: collision and suturing with Siberia and Kazakhstan[J]. Tectonophysics, 114: 43-81.

ZHAO Yue, YANG Zhen-yu, MA Xing-hua. 1994. Geotectonic transition fromPaleo asian system and Paleotethyan system to Paleopacific active continental margin in eastern Asia[J]. Scientia Geologica Sinica, 29(2): 105-114(in Chinese with English abstract).

ZONENSHAIN L P, KUZMIN M I, NATAPOV L M. 1990. Geology of the USSR: A Plate Tectonic Synthesis[J]. Geodynamics Series, 21: 242.

ZONENSHAIN L P, SAVOSTIN L A. 1981. Geodynamics of the Baikal rift zone and plate tectonics of Asia[J]. Tectonophysics, 76: 1-45.

ZORIN Y A, SKLYAROV E V, BELICHENKO V G, MAZUKABZOV A M. 2007. Evolution of island arcs and geodynamics of the eastern Central Asian Foldbelt in the Neogea[J]. Doklady Earth Sciences, 412: 39-42.

ZORIN Y A. 1999. Geodynamics of the western part of the Mongolia–Okhotsk collisional belt, Trans-Baikal region (Russia) and Mongolia[J]. Tectonophysics, 306: 33-56.

Tectonic Deformation and Dynamic Characteristics of the Middle Part of the Mongolia–Okhotsk Collisional Belt, Mongolia

HUANG Shi-qi1), DONG Shu-wen1)*, ZHANG Fu-qin2), MIAO Lai-cheng2), ZHU Ming-shuai2)
1) Chinese Academy of Geological Sciences, Beijing 100037; 2) Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029

As an important part of the Central Asian Orogenic Belt, the Mongolia–Okhotsk collisional belt has attracted much attention for its tectonic deformation and dynamic characteristics. Along the middle part of the Mongolia–Okhotsk collisional belt, five ductile deformation sites and a brittle deformation site were analyzed to reveal its tectonic deformation and dynamic features. B style fold, crumple structure, A style fold, mineral stretching lineation and S-C fabric indicate NW–SE shearing. This information reveals that might have existed a large collision or multi-periodic collisions in the same direction, which resulted in the formation of the Mongolia–Okhotsk collisional belt. The forming time and global tectonic settings as well as the dynamic origin of the Mongolia–Okhotsk collisional belt were discussed. This tectonic belt was mainly formed during the middle Jurassic-early Cretaceous period under the tectonic setting of the East Asian multi-direction convergence. The brittle deformation of Site mg6 was analyzed and two paleo-stress fields were restored, i.e., the NW–SE compression stress field and the E–W compression stress field. The NW–SE compression stress field might have resulted from the distant effect of the westward subduction of the Paleo-Pacific plate during the Jurassic and Cretaceous, whereas the E–W compression stress field probably resulted from the distant effect of the India-Asia collision during the early Cenozoic.

P542; P541

A

10.3975/cagsb.2014.04.03

本文由国家专项“深部探测与实验研究”(编号: SinoProbe-08-01)资助。

2013-07-11; 改回日期: 2014-04-15。责任编辑: 张改侠。

黄始琪, 男, 1984年生。博士研究生。构造地质专业。通讯地址: 100037, 北京市西城区百万庄大街 26号。电话: 010-68999606。E-mail: qi283463544@163.com。

*通讯作者: 董树文, 男, 1954 年生。研究员, 博士生导师。长期从事构造地质与碰撞造山带研究。通讯地址: 100037, 北京市西城区百万庄大街26号。电话: 010-68999606。E-mail: swdong@cags.ac.cn。