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| 1 | New finding of microdiamonds in eclogites from Dabie-Sulu region in central-eastern China显示文摘Micro-diamonds were only found ten years ago in eclogite associated with marble at Xindian in the Dabie Mountains. This paper reports our new finding of micro-diamonds not only in eclogites at Maobei in the Sulu region and at Xindian and Laoyoufang in the south part of the Dabie Mountains (South Dabie), but also in eclogites at Baizhangya and Huangweihe in the northern part of the Dabie Mountains (North Dabie) that has usually been considered not to experience ultrahigh pressure metamorphism. Except the micro-diamond at Huangweihe that was found from the artificial heavy sands of zircons used for isotopic dating, the micro-diamonds from other localities were identified in thin sections of the eclogites. Besides a few interstitial grains, most of the micro-diamond grains in thin sections occur as inclusion in garnet. Three crystals of micro- diamond at Maobei in the Sulu region are sized in 120, 60 and 30 mm, respectively. Crystal forms look like octahedron and the composite of octahedron and hexahedron. The largest micro-diamond crystal comes from Xindian, which is measured to be 180 mm in diameter with distinct zonal structure and inclusions. The zonal structure occurs as an inclined octahedron inside rounded by an incomplete hexagonal girdle. A smaller micro-diamond inclusion occurs inside the central octahedron, and a larger graphite inclusion is within the outer zone. The Laoyoufang micro-diamond is partially retrograded to graphite. Micro-diamond from the Baizhangya eclogite in the ultramafic rock belt of North Dabie is an aggregate of 70 mm×90 mm in size. All the micro-diamonds are confirmed by the Raman spectrum analysis. The occurrence of the micro-diamonds from the eclogites in the ultramafic rock belt of North Dabie demonstrates that this region was also subjected to ultrahigh pressure metamorphism as well as the South Dabie did. | XUShutong LIUYican CHENGuanbao RobertoCompagnoni FrancoRolfo HEMouchun LIUHuifang | 2003 | Chinese Science Bulletin2003，48，10： | 49 |
| 2 | 大别山-苏鲁碰撞造山带构造几何学、运动学和岩石变形分析显示文摘按照构造几何学特点和运动学特征我们把大别山-苏鲁造山带的分为三个构造单元:南部,中部和北部。造山带南部为一套构造堆叠体系;中部为一个混合岩穹窿,浅变质的砂岩、板岩和片岩构成了大别山-苏鲁造山带的北部构造单元。造山带南部的构造堆叠体系主要由前陆褶皱带构成:未变质的新元古代-早三叠世的沉积地层;由“宿松群”北部和苏北地区的“海州群”构成的高压变质岩石单元及含柯石英和金刚石的超高压变质岩石单元。造山带中部的混合岩穹隆由大别山地区的罗田穹隆和苏鲁地区的莱西-栖霞穹隆构成。同样大别山北部的浅变质“佛子岭-卢镇关群”和胶东地区浅变质的“蓬莱群”构成了造山带北部的构造堆叠体系。同时大别山和苏鲁两个构造地体均经历了相似的多期构造变形:沿 NW-SE 向矿物拉伸线理发育的上部指北的剪切变形代表着造山带主变形期的变形;早期向南逆冲的韧性剪切变形和沿中部混合岩穹隆边缘发育的重力滑脱变形体系,后者代表了混合岩穹隆形成时的垂向缩短作用。正是由于构造几何学和多期变形的可对比性决定了这两个变质地体具有相同的地球动力学背景。 | 林伟 王清晨 石永红 | 2005 | 岩石学报2005，21，4： | 37 |
| 3 | Decoupling of surface and subsurface sutures in the Dabie orogen and a continent-collisional lithospheric-wedging model: Sr-Nd-Pb isotopic evidences of Mesozoic igneous rocks in eastern China显示文摘There are significant differences of Nd and Pbisotopic compositions between Mesozoic mafic igneous rocks from the North China Block (NCB) and the South ChinaBlock (SCB). Mesozoic mantle-derived igneous rocks fromthe North China Block have very low e Nd values (-15 to -21), and 206Pb/204Pb ratios (< 17.9), while those in the SCB are characterized by e Nd > -10 and 206Pb/204Pb > 18.3. The verylow e Nd values (-16 to -20) and 206Pb/204Pb ratios (< 17.3) of the early Cretaceous mafic-ultramafic intrusions developedin the north part of the Dabie orogen (NDZ) suggest that the deep lithosphere underneath the NDZ belongs to the NCBbut not the SCB. Therefore, although the surface suture be-tween the NCB and SCB is located on the north side of theNDZ, the subsurface suture between the NCB and SCBshould be located to the south side of the NDZ. This is con-sistent with the previous suggestion that the subsurface su-ture in the Sulu terrane east of the Tanlu fault was the south displacement, but contradictory to northward continentalsubduction of the SCB. A continent-collisional lithospheric-wedging model can interpret the decoupling of the surface and subsurface sutures in the Dabie-Sulu orogen. After slabbreak-off, the continuing convergence of two continental blocks must increase the compression force acting on the suture zone, which might induce the lithosphere splitting of SCB. Thus, the lower crust and lithospheric mantle on thesouth margin of the NCB can wedge into the north margin of the lithosphere of the SCB along the Dabie-Sulu collisionzone. This process caused the overthrust of the mid-upper continental crust with exhumed ultrahigh pressure meta-morphic (UHPM) rocks and underthrust of the deep litho-sphere of the SCB. It could be an important mechanism re-sponsible for the second rapid cooling and uplifting of theUHPM rocks and lithospheric delamination as well as thecorresponding magmatism in Jurassic in the Dabie orogen.The southward movement of subsurface suture in theDabie-Sulu orogen may also provide a tectonic setting indepth for the large-scale Mesozoic magmatic-metallogenesis along the middle-lower reaches of the Yangtse River in east-ern China. | LI Shuguang & YANG Wei School of Earth and Space Sciences, University of Science and Tech-nology of China, Hefei 230026, China | 2003 | Chinese Science Bulletin2003，48，8： | 37 |
| 4 | 大别山下地壳岩石及其深俯冲显示文摘本文对大别山下地壳岩石的主要组成及其变质岩石学和年代学特征进行了系统总结,并首次报道了作者等最近在罗田穹隆中发现的镁铁质下地壳岩石俯冲变质成因的榴辉岩及其有关片麻岩的 SHRIMP 锆石 U-Pb 同位素年代学的最新研究成果。大别山这种不寻常的镁铁质下地壳俯冲成因榴辉岩为研究大陆深俯冲和陆壳物质再循环以及对地幔不均一性的影响提供了重要对象和可能性。根据阴极发光图像及矿物包体组合,罗田榴辉岩中继承锆石可分为两种即具有岩浆结晶环带的岩浆锆石和含有石榴子石+紫苏辉石+斜长石等麻粒岩相变质矿物包体的变质锆石,而且这两种继承锆石常具有舍石榴子石+绿辉石等榴辉岩相矿物包体的增生边。SHRIMP U-Pb 定年结果表明,继承岩浆锆石的^(206)Pb/^(238)U 年龄为791±9Ma、含麻粒岩相矿物包体的继承变质锆石的^(206)Pb/^(238)U 年龄为794±10Ma、含榴辉岩相矿物包体的锆石增生边的^(206)Pb/^(238)U 年龄值为212±10Ma。罗田榴辉岩的围岩——含石榴子石英云闪长质片麻岩中锆石的 CL 图像具有特征的核-幔-边结构即表现为继承岩浆锆石核-高压变质幔-退变质增生边,高压变质幔给出罗田片麻岩中印支期高压变质的精确年龄为218±3Ma。因此,罗田榴辉岩的原岩时代与早期麻粒岩相变质时代一致,均为晚元古代,证明华南陆块北缘晚元古代岩浆板底垫托的存在。而且,大别山下地壳岩石参与了印支期大陆深俯冲,但与南大别带具有不同的折返过程即前者经历了麻粒岩相退变质过程。此外,北大别带榴辉岩的印支期峰期变质时代(212±4Ma)比南大别带年轻(226±3Ma),这可用大陆叠瓦式深俯冲模式来解释。 | 刘贻灿 李曙光 | 2005 | 岩石学报2005，21，4： | 30 |
| 5 | 大别山沙村中生代A型花岗岩和基性岩的源区演化关系显示文摘A型花岗岩的成因虽存在不同的认识模式,但对大别山沙村A型花岗岩的岩石化学和地球化学研究结果表明,其物质源自大陆岩石圈地幔的部分熔融,含有古老地壳信息。结合被侵入基性岩的地球化学和年代学资料,推测大别造山带中生代岩石圈地幔的地球化学性质与下扬子地幔相似。花岗岩中锆石SHRIMP法U-Pb年龄为119.0±3.2Ma,说明其岩浆侵位于早白垩世,与邻近的基性岩侵位时间相近但稍晚。在三叠纪因大陆俯冲碰撞增厚的岩石圈在早白垩世被拉张减薄,含有古老地壳成分的扬子陆下岩石圈地幔及其上覆下地壳发生部分熔融,形成了不同成分的碰撞后岩浆岩。其中部分基性岩浆分异结晶成为辉长岩,而A型花岗岩可能是同一地幔源区物质小比例部分熔融后分异结晶的产物。 | 谢智 郑永飞 闫峻 钱卉 | 2004 | 岩石学报2004，20，5： | 24 |
| 6 | 大别山千鹅冲钼矿区花岗岩的SHRIMP锆石U-Pb年龄、Hf同位素组成及微量元素特征显示文摘千鹅冲斑岩型钼矿床位于东秦岭-大别钼矿带东部的大别山地区。矿体主要赋存于千鹅冲隐伏花岗岩体上部(外接触带)的南湾组片岩中,少量产于花岗岩体内。矿体下部的隐伏岩体中主要见有二长花岗岩和花岗斑岩。SHRIMP锆石UPb定年表明,二长花岗岩和花岗斑岩的侵位年龄分别为130±2Ma(MSWD=1.4)和129±2Ma(MSWD=1.9),二者年龄一致,说明隐伏岩体形成于早白垩世。锆石Hf同位素分析结果表明,千鹅冲钼矿中二长花岗岩和花岗斑岩的εHf(t)值分别变化于-24.5~-2.7和-19.8~-11.2之间,变化范围较大,说明它们主要来源于古老地壳的部分熔融,也有年轻组分的参与。两阶段模式年龄(t DM2)和古元古代的继承锆石指示这些花岗岩的原岩中含有古元古代-太古代的基底岩石。二长花岗岩和花岗斑岩中的锆石的Ce4+/Ce3+比值平均值分别为287.4和55.9,说明形成二长花岗岩的岩浆具有更高的氧逸度,但钼成矿与形成较晚的花岗斑岩具有更紧密的成因联系。千鹅冲钼矿形成于大别造山带早白垩世的伸展构造体制下,造山带下地壳拆沉作用造成的软流圈上涌和壳幔相互作用可能为钼矿的形成提供了成矿物质。 | 高阳 叶会寿 李永峰 罗正传 李法岭 熊必康 孟芳 | 2014 | 岩石学报2014，30，1： | 24 |
| 7 | 北淮阳新元古代基性侵入岩年代学初步研究显示文摘大别造山带北部北淮阳褶皱带中分布少量变质变形基性侵入体,错石U-Pb研究的初步结果表明,它们的形成时代是新元古代(78±18Ma),与北大别杂岩带中TTG片麻岩的形成时代一致。它们不仅形成时代与北大别杂岩带中基性-超基性岩不同,而且表现出与北大别杂岩带中基性侵入体不一致的主量元素地球化学信息。 | 谢智 陈江峰 张巽 周泰禧 杨刚 李惠民 | 2002 | 地球学报2002，23，6： | 23 |
| 8 | U-Pb isotopic compositions of the ultrahigh pressure metamorphic (UHPM) rocks from Shuanghe and gneisses from Northern Dabie zone in the Dabie Mountains, central China: Constraint on the exhumation mechanism of UHPM rocks显示文摘The U-Pb isotopic study of the ultrahigh pressure metamorphic (UHPM) rocks and gneisses from the Dabie Mountains shows that the UHPM rocks exposed in the Southern Dabie zone have relatively low Pb contents (most < 4×10-6), high U/Pb ratios (most > 0.1), and a large variation of Pb isotopic ratios with relatively high radiogenic Pb (206Pb/204Pb = 17.026—20.781). Their low Pb contents could be the result of Pb loss caused by fluid expulsion during continental subduction, while their high radiogenic Pb values can be explained by the mixing of the upper crust Pb and the mantle Pb. In contrast, the gneisses exposed in the Northern Dabie zone have higher Pb contents (most > 4×10-6), lower U/Pb ratios (< 0.07), and lower Pb isotopic ratios (206Pb/204Pb = 15.799—17.204), which are similar to those of the Mesozoic granites developed in both Northern and Southern Dabie zones. It is suggested that the Northern Dabie zone may have experienced a smaller fluid expulsion and Pb loss during the continental subduction, and their Pb isotopic compo-sitions could be explained by the mixing of the lower crust Pb and the mantle Pb. Their initial Pb isotope ratios at 230 Ma suggest that the U/Pb ratios of the UHPM rocks in the Southern Dabie zone are higher than those of the gneisses in the Northern Dabie zone in a long period of time be-fore the continental subduction. The above observations suggest that the protoliths of the UHPM rocks in the Southern Dabie zone are upper crustal rocks in the subducted continental crust, while the gneisses in the Northern Dabie zone have the middle-lower crust features. Based on these observations, a model for the exhumation of UHPM rocks is proposed, i.e. the detachment be-tween the upper crust and lower crust in the subducted continental crust could have occurred dur-ing subduction, thus the subducted upper crust was uplifted by buoyancy and moved southward along the thrust. | 李曙光 黄方 周红英 李惠民 | 2003 | Science China Earth Sciences2003，46，3： | 19 |
| 9 | “罗田穹隆”中的下地壳俯冲成因榴辉岩及其地质意义显示文摘在“罗田穹隆”中发现了下地壳俯冲成因榴辉岩 .榴辉岩呈透镜状或板状产于含石榴子石条带状片麻岩中 .新鲜的榴辉岩主要由石榴子石、绿辉石、金红石等组成 ,含少量退变质的角闪石、斜长石、紫苏辉石、透辉石、(钛 )磁铁矿和石英等 .研究区榴辉岩以保留早期麻粒岩相变质矿物残留体以及经受晚期麻粒岩相和角闪岩相退变为特征 ,指示它们由扬子镁铁质下地壳麻粒岩相岩石俯冲到深部发生变质并形成榴辉岩 ,然后折返至下地壳发生麻粒岩相退变 ,由于麻粒岩相退变质阶段仅以后成合晶形式出现 ,因而它们可能在下地壳停留时间不长 ,就又进一步被构造抬升至中上地壳而发生角闪岩相退变 .大别山造山带乃至扬子板块北缘现今缺乏厚层镁铁质下地壳 ,它们也很少出露地表 ,推测这些俯冲的镁铁质下地壳可能已拆离再循环进入地幔 .从而为“罗田穹隆”的形成和演化以及大别山高压 | 刘贻灿 徐树桐 李曙光 陈冠宝 彭练红 | 2005 | 地球科学(中国地质大学学报)2005，30，1： | 15 |
| 10 | 大别山造山带高压-超高压变质岩的折返过程显示文摘高压-超高压变质岩的形成与折返是地球动力学过程,虽人眼不能见及,但在岩石中留下种种记录。本文以大别山为例对高压-超高压变质岩的折返过程进行了探讨。文中(1)综合构造地质学和地球物理学观测资料,剖析了大别山造山带的结构构造,指出了作为高压-超高压变质岩折返通道的莫霍面断口和折返形成的挤压穹隆地壳结构;(2)综合变质岩石学P-T-t轨迹研究资料,追踪高压-超高压变质岩在地下的运动轨迹,揭示了其在俯冲-折返过程不同时段经过的深度和运动速率,并指出其向南的折返极性;(3)结合沉积岩石学研究资料,利用合肥盆地中砾岩成分和碎屑白云母Si含量记录,限定了高压-超高压变质岩折返至地表的时间为中侏罗世前。基于上述资料,本文重建了大别山高压-超高压变质岩的三阶段折返过程,指出大别山包含三个岩片,于230Ma左右分别从不同深度快速折返,折返速率为3~10km/Ma,于210Ma左右进入中地壳,并于180Ma左右快速折返(折返速率为3km/Ma左右)至上地壳,白垩纪折返速率极慢(0.1km/Ma左右)。 | 王清晨 | 2013 | 岩石学报2013，29，5： | 14 |
| 11 | 北大别片麻岩的超高压变质证据——来自锆石提供的信息显示文摘本文对北大别片麻岩锆石中矿物包体及年代学进行了研究,首次发现了北大别片麻岩的超高压变质作用证据。结合阴极发光图像和同位素定年,片麻岩锆石中矿物包体组合至少可分出三期:(1)原岩岩浆矿物组合,即斜长石、黑云母、石英和磷灰石;(2)超高压变质矿物组合,即金刚石、石榴子石和金红石等;(3)麻粒岩相退变质矿物组合,如透辉石等。其中,金刚石和石榴子石主要以包体形式被包裹于透辉石中,而透辉石是北大别麻粒岩相退变质阶段形成的代表性矿物。锆石SHRIMP U-Pb定年结果表明,北大别片麻岩的峰期变质时代和麻粒岩相退变质时代分别为218±3Ma和199±10Ma。这些证明北大别片麻岩,如同其中的榴辉岩一样,经过了印支期超高压变质作用。 | 刘贻灿 李曙光 徐树桐 古晓锋 | 2006 | 岩石学报2006，22，7： | 13 |
| 12 | Eclogites from the Northern Dabie Mountains, eastern China: Geochemical characteristics, Sr-Nd isotopic compositions and tectonic implications显示文摘The petrologic geochemical and Sr-Nd isotopic compositions of the eclogites from the mafic-ultramafic rock belt (MUMRB) in the Northern Dabie Mountains indicate that: (1) the protoliths of most of eclogites are tholeiitic basalt and a few may be gabbro, and most of them produced from the Yangtze subducted continental crust (lower crust and formed during the deep subduction) and a part may be from paleo-oceanic relics between the Yangtze and North China continental plates; (2) their positive Nb anomalies and related trace element characteristics show that they did not form in the island-arc setting; (3) the metamorphosed MUMRB with eclogite and meta-peridotite blocks along the southern part of the Mozitan-Xiaotian fault zone may represent the suture zone produced during the collision between the Yangtze and North China continental plates, which included the Yangtze subducted continental crust and paleo-oceanic relics. | 刘贻灿 徐树桐 李曙光 江来利 吴维平 陈冠宝 苏文 | 2000 | Science China Earth Sciences2000，43，S1： | 12 |
| 13 | 大别造山带东段扬子陆块和华北陆块间缝合带的位置显示文摘大别山为扬子陆块和华北陆块之间的碰撞造山带.构造-岩石单元的岩石组成、同位素年代学资料和构造关系表明,大别山东段主要由扬子陆块北缘不同变质程度的变质基底和少量浅变质盖层组成,没有代表蛇绿混杂岩和华北陆块南缘古生代活动大陆边缘的火山-侵入岩建造.各主要构造-岩石单元间的界线为超高压变质岩折返过程中形成的伸展型剪切带,大别山北部的伸展-逆冲推覆构造也是超高压变质岩折返过程中伸展构造的一部分,其中不存在具有缝合带意义的重要构造界线.因此,在大别山东段,华北陆块和扬子陆块间的缝合带既不是水吼-五河剪切带,也不是磨子潭-晓天断裂.根据地球物理资料推测,南北陆块间的缝合带应分布在信阳-舒城断裂的前缘,但现在覆于合肥盆地中新生代沉积之下. | 江来利 吴维平 储东如 | 2005 | 地球科学(中国地质大学学报)2005，30，3： | 10 |
| 14 | 大别山北部榴辉岩的大地构造属性及冷却史显示文摘岩石地球化学及同位素年代学研究表明 ,大别山北部榴辉岩的大部分属印支期扬子俯冲陆壳 (下地壳 )的一部分 ;大致沿磨子潭 -晓天断裂附近分布的含榴辉岩、大理岩和变质橄榄岩的镁铁 -超镁铁质岩带可能代表扬子与华北 2个大陆板块之间的变质构造混杂岩带 ,它应接近于扬子与华北 2个大陆板块之间的缝合线 (镁铁 -超镁铁质岩带以北 ) ,而五河 -水吼剪切带则可能代表扬子俯冲陆壳内部的 1条拆离带或滑脱带 .冷却史研究表明 ,大别山北部榴辉岩峰期变质后初期 (2 30~ 2 10Ma)仅抬升到下地壳水平 ,因而未经历降温过程并具有比大别山南部榴辉岩较低的抬升速率 ,峰期变质后较慢的抬升速率及相应的近于等温或局部升温阶段也许是造成大别山北部榴辉岩与南部超高压带中榴辉岩差异的重要原因之一 ;同时 。 | 刘贻灿 徐树桐 李曙光 江来利 陈冠宝 吴维平 | 2003 | 地球科学(中国地质大学学报)2003，28，1： | 10 |
| 15 | 大别山及苏鲁地区微粒金刚石分类及其大地构造意义显示文摘1992年发现大别山首例微粒金刚石之后,又于2003年和2004年在大别山和苏鲁地区的榴辉岩薄片中和榴辉岩的人工重砂中发现了微粒金刚石。本文报道其中尚未发表的7颗,并对2颗较大的薄片中的微粒金刚石和2颗自由晶体金刚石进行拉曼光谱和红外光谱测试。研究结果表明,本区所有微粒金刚石都为IaA和IaB型金刚石的混合体。缺少Ib型金刚石,表明没有人造金刚石的混入。薄片中的金刚石大部分为石榴子石的包裹体,少数产出于颗粒之间,直径为30~180μm。自由颗粒微粒金刚石直径为400~700μm。在大别山北部,不但又一次找到了微粒金刚石,还在石榴子石中发现有单斜辉石、磷灰石和金红石的出溶。这表明北大别不但是超高压地质体,而且可能是本区俯冲最深的地质体。 | 徐树桐 刘贻灿 陈冠宝 季寿元 倪培 萧万生 | 2005 | 地质通报2005，24，12： | 9 |
| 16 | Early Cretaceous uplift history of the Dabie orogenic belt: Evidence from pluton emplacement depths显示文摘The North Dabie complex unit(NDC)is a widely exposed petro-tectonic unit.To understand post-orogenic uplift history and mechanism of the Dabie orogenic belt,many samples of granite,granodiorite,diorite,and alkali feldspar granite with precise zircon U-Pb ages were collected for electron microprobe analysis of hornblende.Emplacement pressure values were then calculated by using an Al-in-hornblende geobarometer.The result shows that total Al(AlT)values in hornblende range from 1.17to 1.97 p.f.u.,XFe(=Fe/(Fe+Mg))from 0.4 to 0.65,and corresponding pressure values from 256.8 to 676.2 MPa for AlT greater than 1.17.It is suggested that although the main mechanism for the uplift is tectonic extension,inhomogeneous uplift related to the pluton emplacement is also important during post-orogenic evolution of the Dabie orogenic belt.Emplacement depth distribution of the plutons shows that uplift in the NDC is affected by horst-graben structures since 120 Ma. | WANG YongSheng WANG HaiFeng SHENG Yong XIANG BiWei | 2014 | Science China Earth Sciences2014，57，5： | 8 |
| 17 | 北大别超高压榴辉岩的快速折返与缓慢冷却过程显示文摘岩石学研究表明,北大别超高压榴辉岩经过了超高压和高压榴辉岩相变质作用以及麻粒岩相叠加和角闪岩相退变质作用。其中,高压麻粒岩相和角闪岩相变质阶段形成的后成合晶以及石榴子石和单斜辉石等矿物中成分分带的存在,证明该区榴辉岩经历了一个快速折返过程;而不同变质阶段的温度、压力和形成时代,却反映该区榴辉岩在峰期超高压变质作用之后又经历了一个缓慢冷却过程。超高压岩石折返期间的缓慢冷却过程也许正是北大别长期难以发现柯石英和有关超高压证据的重要原因。因此,本文为大别山不同超高压岩片的差异折返模型的建立提供了新的证据。 | 刘贻灿 古晓锋 李曙光 | 2009 | 岩石学报2009，25，9： | 8 |
| 18 | 超高压变质岩的放射性同位素体系及年代学方法显示文摘深刻理解同位素在超高压变质及退变质过程中的地球化学行为对获得超高压变质岩准确并有明确意义的年龄值是非常重要的。对 Sm-Nd,Rb-Sr 同位素体系,只有变质矿物同位素体系达到平衡才能给出精确有意义的等时线年龄。研究表明,与副变质岩互层的细粒榴辉岩的高压变质矿物之间,或者强退变质岩石的退变质矿物之间,其 Nd,Sr 同位素可以达到平衡;然而高压变质矿物与退变质矿物之间 Nd,Sr 同位素不平衡。由于全岩样品总是含有数量不等的退变质矿物,因此石榴石+全岩 Sm-Nd 法或多硅白云母+全岩 Rh-Sr 法将有可能给出无地质意义的年龄。通常低温榴辉岩的高压变质矿物之间存在Nd 同位素不平衡。超高压变质岩多硅白云母所含过剩 Ar 主要源于榴辉岩原岩中角闪石在变质分解时释放出来的放射成因 Ar。因此,不含榴辉岩的花岗片麻岩多硅白云母基本不含过剩 Ar。对变质锆石成因的准确判断是正确理解锆石 U-Ph 年龄意义的关键。本文对不同成因锆石的判别标志及年龄意义做了总结,并指出将阴极发光图形,锆石痕量元素组成及矿物包裹体鉴定相结合是进行锆石成因鉴定的有效方法。高压变质或退变质增生锆石组成单一,是理想变质定年对象。然而变质重结晶锆石域常是重结晶锆石和继承晶质锆石的混合区,因而给出混合年龄。只有完全变质重结晶锆石才能给出准确变质时代。 | 李曙光 侯振辉 李秋立 | 2005 | 岩石学报2005，21，4： | 8 |
| 19 | Geochronology Constraints on Transformation Age from Ductile to Brittle Deformation of the Shangma Fault and Its Tectonic Significance,Dabieshan,Central China显示文摘By a detailed investigation of geometry and kinematics of the Shangma fault in Dabieshan,three different crust levels of extension movement have been recognized in sequence from the deep to the shallow: low-angle ductile detachment shearing with top to the NW; low-angle normal fault with top to the NW or NWW in brittle or brittle-ductile transition domain;high-angle brittle normal fault with top to the W or NWW. Two samples were chosen for zircon U-Pb age dating to constrain the activity age of the Shangma fault. A bedding intrusive granitoid pegmatite vein that is parallel to the foliation of the low-angle ductile detachment shear zone of the country rock exhibits a lotus-joint type of boudinage deformation,showing syn-tectonic emplacing at the end of the ductile deformation period and deformation in the brittle-ductile transition domain. The zircon U-Pb dating of this granitoid pegmatite vein gives an age of (125.9±4.2) Ma,which expresses the extension in the brittle-ductile transition domain of the Shangma fault. The other sample,which is collected from a granite pluton cutting the foliation of the low-angle ductile detachment shear zone,gives a zircon U-Pb age of (118.8±4.1) Ma,constraining the end of the ductile detachment shearing. Then the transformation age from ductile to brittle deformation can be constrained between 126–119 Ma. Combined with the previous researches,the formation of the Luotian dome,which is located to the east of the Shangma fault,can be constrained during 150–126 Ma. This study gives a new time constraint to the evolution of the Dabie orogenic belt. | 王国灿 王朴 刘超 王岸 叶润清 | 2008 | Journal of China University of Geosciences2008，19，2： | 7 |
| 20 | Zircon U/Pb Dating of Cretaceous Adakitic Volcanic Rocks in the Eastern Part of North Dabie Mountains显示文摘Mesozoic volcanic rocks in the eastern part of the North Dabi e Mountains are rich in Na (Na\-2O=\{4.03%\}, Na\-2O/K\-2O=\{1.31\}), Sr and Ba , and high in Sr/Y ratio but low in Nb, Y and H REE. They have experienced strong fractionation of REE \, and are similar to adakite in geochemical characteristics. The U-Pb dating of zircon from the volcanic rocks is Ma, belonging to Early Cretaceous. These rocks are similar to the volcanic rocks of North Huaiyang not only in age and rare-earth element and trace element geochemistry, but also in the formati on temperature and pressure of the minerals. The results indicated that the dela mination of mountain root and underplating of mafic-ultramafic magma had happen ed in the Dabie orogen before Early Cretaceous. Mesozoic magmatism was intense i n the North Dabie Mountains, including the intrusion of mafic-ultramafic magma, uplifting of gneiss dome, explosion of volcanic rocks and intrusion of granitic magma. The Mesozoic volcanic rocks in the eastern part of the North Dabie Mount ains may be one part of the Mesozoic volcano-intrusive complex belt of North Hu aiyang. The existence of Mesozoic volcanic remnant cap means the denudation of t he Dabie orogenic belt was not very strong since Early Cretaceous. | 薛怀民 董树文 刘晓春 | 2003 | Chinese Journal Of Geochemistry2003，22，3： | 7 |
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