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| 1 | 大陆造山运动:从大洋俯冲到大陆俯冲、碰撞、折返的时限--以北祁连山、柴北缘为例显示文摘北祁连山和柴北缘是典型的早古生代大陆造山带,分别发育有北祁连山大洋型俯冲缝合带和柴北缘大陆型俯冲碰撞带。作为早古生代大洋冷俯冲的典型代表,北祁连山经历了从新元古代-寒武纪大洋扩张、奥陶纪俯冲和闭合及早泥盆世隆升造山的过程。高压变质岩变质年龄为490~440Ma,证明古祁连洋经历了至少50m.y.的俯冲过程。柴北缘超高压变质带是大陆深俯冲的结果,岩石学、地球化学和同位素年代学表明,柴北缘超高压变质带中榴辉岩的原岩分别来自洋壳和陆壳两种环境。高压/超高压变质的蛇绿岩原岩的年龄为517±11Ma,与祁连山蛇绿岩年龄一致。榴辉岩早期的变质年龄为443~473Ma,与祁连山高压变质年龄一致,代表大洋地壳俯冲的时代,而柯石英片麻岩和石榴橄榄岩所限定的超高压变质时代为420~426Ma,代表大陆俯冲的年龄。从大洋俯冲结束到大陆俯冲最大深度的转换时间最少需要20m.y.。自420Ma起,俯冲的大洋岩石圈与跟随俯冲的大陆岩石圈断离,大陆地壳开始折返,发生隆升和造山。北祁连山和柴北缘两个不同类型的高压-超高压变质带反映了早古生代从大洋俯冲到大陆俯冲、隆升折返的造山过程。 | 宋述光 牛耀龄 张立飞 张贵宾 | 2009 | 岩石学报2009，25，9： | 99 |
| 2 | 中亚-蒙古造山带东段的锡林郭勒杂岩:早华力西期造山作用的产物而非古老陆块?——锆石SHRIMP U-Pb年代学证据显示文摘锡林郭勒杂岩是华北板块北缘古生代褶皱带内出露面积最大的变质岩系,以前多被当着前寒武纪的古老地块。本文通过对该杂岩中副片麻岩和正片麻岩的锆石SHRIMP U-Pb年代学研究发现,副片麻岩中的锆石多为岩浆锆石,其^(206)Pb/^(238)U加权平均年龄为406±7Ma,指示它们的原岩主要是由近同期(略早些)的岩浆岩风化后就近沉积的产物,该年龄应代表源区(岛弧型?)花岗岩的形成时间,同时也是副片麻岩原岩沉积的下限年龄。正片麻岩中岩浆锆石的^(206)Pb/^(238)U加权平均年龄为382±2Ma,代表花岗片麻岩原岩的侵位年龄。岩石中锆石的变质增生边的形成年龄为337±6Ma,代表锡林郭勒杂岩发生变质和变形的时间,该变质事件可能与贺根山缝合带内所发生的一次主要的碰撞造山作用有关。这些年龄资料充分说明,锡林郭勒杂岩并非古老地块,而是华力西早期岩浆作用、沉积作用和变质作用事件的产物.整个事件是在较短的时间范围内(~70Ma)完成的,推测该杂岩发育在碰撞造山带的弧前环境。中亚-蒙古造山带东南部(内蒙古的中、东部)碰撞前的构造格局可能不是典型的多岛洋体制,由于缺少古老的陆块,造山过程更多的表现为大洋的大陆化过程,即洋内俯冲形成岛弧,岛弧在被动大陆边缘拼贴聚合转化为新的大陆。 | 薛怀民 郭利军 侯增谦 周喜文 童英 潘晓菲 | 2009 | 岩石学报2009，25，8： | 63 |
| 3 | Mianlüe tectonic zone and Mianlüe suture zone on southern margin of Qinling-Dabie orogenic belt显示文摘The Mianle tectonic zone (Mianle zone), an ancient suture zone in addition to the Shangdan suture in the Qinling-Dabie orogenic belt, marks an important tectonic division geo-logically separating north from south and connecting east with west in China continent. To de-termine present structural geometry and kinematics in the Mianle tectonic zone and to recon-struct the formation and evolution history involving plate subduction and collision in the Qinling-Dabie orogenic belt, through a multidisciplinary study, are significant for exploring the mountain-building orogenesis of the central orogenic system and the entire process of the major Chinese continental amalgamation during the Indosinian. | ZHANG Guowei1, DONG Yunpeng1, LAI Shaocong1, GUO Anlin1, MENG Qingren2, LIU Shaofeng3, CHENG Shunyou1, YAO Anping1, ZHANG Zongqing4, PEI Xianzhi5 & LI Sanzhong6 1. Department of Geology, Northwest University, Xian 710069, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100101, China 3. Earth Science and Resource Faculty, China University of Geosciences, Beijing 100083, China 4. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 5. Changan University, Xian 710054, China 6. Qingdao University of Oceanography, Qingdao 266003, China | 2004 | Science China Earth Sciences2004，47，4： | 57 |
| 4 | Remelting of subducted continental lithosphere: Petrogenesis of Mesozoic magmatic rocks in the Dabie-Sulu orogenic belt显示文摘The Dabie-Sulu orogenic belt was formed by the Triassic continental collision between the South China Block and the North China Block. There is a large area of Mesozoic magmatic rocks along this orogenic belt, with emplacement ages mainly at Late Triassic, Late Jurassic and Early Cretaceous. The Late Triassic alkaline rocks and the Late Jurassic granitoids only crop out in the eastern part of the Sulu orogen, whereas the Early Cretaceous magmatic rocks occur as massive granitoids, sporadic intermedi- ate-mafic intrusive and volcanic rocks throughout the Dabie-Sulu orogenic belt. Despite the different ages for their emplacement, the Mesozoic magmatic rocks are all characterized not only by enrichment of LREE and LILE but depletion of HFSE, but also by high initial Sr isotope ratios, low εNd(t) values and low radiogeneic Pb isotope compositions. Some zircons from the Jurassic and Cretaceous granitoids contain inherited magmatic cores with Neoprotozoic and Triassic U-Pb ages. Most of the Cretaceous mafic rocks have zircon δ18O values and whole-rock δ13C values lower than those for the normal mantle. A systematic comparison with adjacent UHP metaigneous rocks shows that the Mesozoic granitoids and mafic rocks have elemental and isotopic features similar to the UHP metagranite and metabasite, respectively. This indicates that these magmatic and metamorphic rocks share the diagnostic features of lithospheric source that has tectonic affinity to the northern edge of the South China Block. Their precursors underwent the UHP metamorphism and the post-collisional anatexis, respectively at different times and depths. Therefore, the Mesozoic magmatic rocks were derived from anatexis of the subducted continental lithosphere itself beneath the collision-thickened orogen; the geodynamic mechanism of the post-collisional magmatisms is tectonic collapse of orogenic roots in response to lithospheric extension. | ZHAO ZiFu ZHENG YongFei | 2009 | Science China Earth Sciences2009，52，9： | 60 |
| 5 | 造山带中成对出现的高压麻粒岩与榴辉岩及其地球动力学意义显示文摘在一些典型碰撞造山带中,高压麻粒岩与榴辉岩在空间和时间上密切相关,它们之间的关系对揭示碰撞造山带的造山过程和造山机制具有重要意义。本文以中国西部的南阿尔金、柴北缘及中部的北秦岭造山带为例,详细陈述了这3个地区榴辉岩和相关的高压麻粒岩的野外关系、变质演化和形成时代,目的是要建立大陆碰撞造山带中榴辉岩和相关高压麻粒岩形成的地球动力学背景模式。南阿尔金榴辉岩呈近东西向分布在江尕勒萨依-玉石矿沟一带,与含夕线石副片麻岩、花岗质片麻岩和少量大理岩构成榴辉岩-片麻岩单元,榴辉岩中含有柯石英假象,其峰期变质条件为P=2.8~3.0GPa,T=730~850℃,并在抬升过程中经历了角闪岩-麻粒岩相的叠加;大量年代学研究显示其峰期变质时代为485~500Ma。南阿尔金高压麻粒岩分布在巴什瓦克地区,包括高压基性麻粒岩和高压长英质麻粒岩,它们与超基性岩构成了一个大约5km宽的构造岩石单元,与周围角闪岩相的片麻岩为韧性剪切带接触。长英质麻粒岩和基性麻粒岩的峰期组合均具有蓝晶石和三元长石(已变成条纹长石),形成的温压条件为T=930~1020℃,P=1.8~2.5GPa,并在退变质过程中经历了中压麻粒岩相变质作用叠加。锆石SHRIMP测定显示巴什瓦克高压麻粒岩的峰期变质时代为493~497Ma。都兰地区的榴辉岩分布柴北缘HP-UHP变质带的东端,在榴辉岩和围岩副片麻岩中均发现有柯石英保存,形成的峰期温压条件为T=670~730℃和,P=2.7~3.25GPa,退变质阶段经过了角闪岩相的叠加;榴辉岩相变质时代为420~450Ma。都兰地区的高压麻粒岩分布在阿尔茨托山西部,高压麻粒岩包括基性麻粒岩长英质麻粒岩,基性麻粒岩的峰期矿物组合为Crt+Cpx+Pl±Ky±Zo+Rt±Qtz,长英质麻粒岩的峰期矿物组合为:Grt+Kf+Ky+Pl+Qtz。峰期变质条件为T=800~925℃,P=1.4~1.85GPa,退变质阶段经历了角闪岩-绿片岩的改造,高压麻粒岩的变质时代为420~450Ma。北秦岭榴辉岩分布在官坡-双槐树一带,榴辉岩的峰期变质组合为Grt+Omp±Phe+Qtz+Rt,所计算的峰期温压条件为T=680~770℃和P=2.25~2.65GPa,年代学数据显示榴辉岩的变质时代为500Ma左右。北秦岭高压麻粒岩分布在含榴辉岩单元的南侧松树沟一带,包括高压基性麻粒岩和高压长英质麻粒岩,与超基性岩在空间上密切伴生,高压麻粒岩的峰期温压条件为T=850~925℃,P=1.45~1.80GPa,锆石U-Pb年代学研究显示其峰期变质时代为485~507Ma。以上三个实例显示,出现在同一造山带、在空间上伴生的高压麻粒岩和榴辉岩有各自不同的变质演化历史,但榴辉岩中的榴辉岩相变质时代和相邻的高压麻粒岩中的高压麻粒岩相变质作用时代相同或相近,这种成对出现的榴辉岩和高压麻粒岩代表了它们同时形成在造山带中不同的构造环境中,即榴辉岩的形成于大陆俯冲带中,而高压麻粒岩可能形成在俯冲带之上增厚的大陆地壳根部。 | 张建新 于胜尧 孟繁聪 李金平 | 2009 | 岩石学报2009，25，9： | 46 |
| 6 | 太行山南段符山高镁闪长岩的成因——拆沉陆壳物质熔融的熔体与地幔橄榄岩反应的结果显示文摘本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。含橄榄岩包体的寄主岩——角闪闪长岩中的锆石可划分为两种:一是代表寄主岩浆结晶的锆石:内部结构均匀、呈条带状吸收、自形-半自形晶形,具有较高的Th/U比值(1.10~4.08),其^(206)Pb/^(238)U年龄介于123~128Ma之间,12个点的加权平均值为125±1Ma,这表明岩体的形成时代为早白垩世;二是捕获或继承锆石:具有核边结构、吸收程度不均匀、呈浑圆状和自形-半自形两种,它们的Th/U比值介于0.32~2.03之间,构成了3组^(207)Pb/^(206)Pb加权平均年龄:2503±11Ma、2181±26Ma和1778±36Ma。该类岩石的SiO_2和MgO含量分别介于56.69%~59.21%和3.60%~6.33%之间;且以高Mg~#(0.51~0.64)、富Na(Na_2O/K_2O大于1)、高Cr(93.1×10^(-6)~420×10^(-6))、Ni(35.1×10^(-6)~137×10^(-6))为特征。该类岩石强烈富集轻稀土元素和大离子亲石元素、明显亏损高场强元素,(^(87)Sr/^(86)Sr)_i、ε_(Nd)(t)值和(^(206)Pb/^(204)Pb)_i分别变化于0.70581~0.70641、-8.30~-16.56和17.052~17.512之间。综合上述特征,同时结合地慢橄榄岩包体的特征和古元古代捕获锆石的大量存在,认为符山高镁闪长岩的原始岩浆起源于拆沉陆壳物质的部分熔融,其后经历了与地幔橄榄岩的反应过程。 | 许文良 杨德彬 裴福萍 于洋 | 2009 | 岩石学报2009，25，8： | 39 |
| 7 | Contemporary crustal deformation of the Chinese continent and tectonic block model显示文摘We obtain the preliminary result of crustal deformation velocity field for the Chinese con-tinent by analyzing GPS data from the Crustal Motion Observation Network of China (CMONOC), particularly the data from the regional networks of CMONOC observed in 1999 and 2001. We de-lineate 9 tectonically active blocks and 2 broadly distributed deformation zones out of a denseGPS velocity field, and derive block motion Euler poles for the blocks and their relative motionrates. Our result reveals that there are 3 categories of deformation patterns in the Chinese conti-nent. The first category, associated with the interior of the Tibetan Plateau and the Tianshan oro-genic belt, shows broadly distributed deformation within the regions. The third category, associatedwith the Tarim Basin and the region east of the north-south seismic belt of China, shows block-likemotion, with deformation accommodated along the block boundaries only. The second category, mainly associated with the borderland of the Tibetan Plateau, such as the Qaidam, Qilian, Xining(in eastern Qinghai), and the Diamond-shaped (in western Sichuan and Yunnan) blocks, has thedeformation pattern between the first and the third, i.e. these regions appear to deform block-like,but with smaller sizes and less strength for the blocks. Based on the analysis of the lithosphericstructures and the deformation patterns of the regions above, we come to the inference that thedeformation modes of the Chinese continental crust are mainly controlled by the crustal structure.The crust of the eastern China and the Tarim Basin is mechanically strong, and its deformationtakes the form of relative motion between rigid blocks. On the other hand, the northward indentation of the Indian plate into the Asia continent has created the uplift of the Tibetan Plateau and the Tianshan Mountains, thickened their crust, and raised the temperature in the crust. The lower crust thus has become ductile, evidenced in low seismic velocity and high electric conductivity observed. The brittle part of the crust, driven by the visco-plastic flow of the lower crust, deforms extensively at all scales. The regions of the second category located at the borderland of the Tibetan Plateau are at the transition zone between the regions of the first and the third categories in terms of the crustal structure. Driven by the lateral boundary forces, their deformation style is also between the two, in the form of block motion and deformation with smaller blocks and less internal strength. | WANG Min (王 敏) SHEN Zhengkang (沈正康) NIU Zhijun (牛之俊) ZHANG Zusheng (张祖胜) SUN Hanrong (孙汉荣) GAN Weijun (甘卫军) WANG Qi (王 琪) REN Qun (任 群) | 2003 | Science China Earth Sciences2003，46，z2： | 33 |
| 8 | An Archean continental block in the Taihangshan and Hengshan regions: Constraints from geochronology and geochemistry显示文摘Recent research on the tectonothermal evolution and geochronology in the Fuping, Hengshan and Wutaishan metamorphic complexes, together with the discoveries of a high-pressure granulite belt in the northern margin of the North China Craton (NCC) and high-pressure metapelites in the Jingangku Group of the Wutaishan complex, suggests that there was a Neoarchean to Paleoproterozoic orogenic belt related to collision between the Eastern and Western continental blocks. Comparison of geological, geochronological, tectonothermal and geochemical data between the Fuping and Hengshan complexes suggests these two complexes most likely originated and evolved as a single lithotectonic domain (i.e., the Taihangshan-Hengshan block) during the early evolution of the North China Craton, probably as an active margin to the Eastern Continental Block. The Taihangshan-Hengshan block has been subjected to intensive and extensive tectono-magmatism and high-grade metamorphism related to collision between the Eastern and Western continental blocks at ~1.80 Ga. | LIU Shuwen , LI Jianghai, PAN Yuanming, ZHANG Jian and LI Qiugen(1. The Key Laboratory of Orogenic Belts and Crustal Evolution, School of Earth and Space Sciences, Peking University, Beijing 100871, China 2. Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada) | 2002 | Progress in Natural Science:Materials International2002，12，8： | 32 |
| 9 | Pre-collision Granites and Post-collision Intrusive Assemblage of the Kelameili-Harlik Orogenic Belt显示文摘The main types of intrusive rocks in the Kelameili-Harlik Hercynian erogenic belt include calc-alkaline granites, diabase dykes, kaligranites and alkaline granites. Investigation in field geology, petrology, mineralogy and geochemistry shows that the calc-alkaline granites belong to the syntexis-type (or I-type) and were formed in a pre-collisional magmatic arc environment. In consideration of the fact that kaligranites have many features of alkaline granites with higher consolidation temperatures than the calc-alkaline granites and show a discontinuity of minor element and REE evolution in respect to the calc-alkaline granites, they could not have been derived by differentiation of magmas for the calc-alkaline granites, but are likely to have been generated in an environment analogous to that for alkaline granites. The triplet of basic dyke swarms, kaligranites and alkaline granites could be regarded as a prominent indication of the initial stage of post-collisional delamination and extension. These | GU Lianxing HU Shouxi CHU Qiang YU Chunshui XIAO Xinjian | 1999 | Acta Geologica Sinica(English Edition)1999，73，3： | 33 |
| 10 | The role of magmatism in the thinning and breakup of the South China Sea continental margin显示文摘INTRODUCTION Magmatism plays a key role in the process of continental margin breakup and ocean formation.Even in the extremely magma-poor Iberia and Newfoundland margin,studies of field outcrops have shown that syn-rift magmatism had participated in rifting from a very early stage and contributed directly to the rifting process.The final transition from exhumed continental mantle to the ocean formation is also triggered by the accumulation and eruption of magma[1]. | Zhen Sun Jian Lin Ning Qiu Zhimin Jian PinXian Wang Xiong Pang Jinyun Zheng Benduo Zhu | 2019 | National Science Review2019，6，5： | 34 |
| 11 | Ultra-high pressure metamorphism of granitic gneiss in the Yinggelisayi area, Altun Mountains, NW China显示文摘 | LIU Liang, SUN Yong, LUO Jinhai, WANG Yan, CHEN Danling & ZHANG Anda The Key Laboratory of Continental Dynamics, Ministry of Education,Department of Geology, Northwest University, Xi抋n 710069, China | 2004 | Science China Earth Sciences2004，47，4： | 27 |
| 12 | Episodic rifting of continental marginal basins and tectonic events since 10 Ma in the South China Sea显示文摘Integrated study on the tectonic, basin filling and thermal evolution of the Tertiary basins on the northern margin of the South China Sea has indicated that the rift continental margin on the northern South China Sea is not a passive margin and that the western margin is characteristic of the transformextension. Episodic rifting and the thermal events since 10 Ma in the area have been documented by the integrated analysis of dynamic process. It has been clarified that the tectono-thermal events have exerted a significant influence on basin features and hydrocarbon accumulation, and particularly, the westward collision of the Lusong Island Arc, the generation of densely spaced faults in the Pearl River Mouth Basin, the rapid subsidence, high heat flow and large-scale over pressure and thermal-fluid breakthrough in the Yinggehai and the Qiongdongnan basins have proved to be the important factors determining the formation of oil and gas in these basins. | Sitian Li Changsong Lin Qiming Zhang Shigong Yang Peikan Wu | 1999 | Chinese Science Bulletin1999，44，1： | 27 |
| 13 | Orogenesis and dynamics of the Qinling Orogen显示文摘The Qinling is a composite orogen which experienced three different developmental stages under distinct tectonic regimes. The main stage (Neo-Proterozoic- Middle Triassic) of the erogenic evolution is a prolonged and complicated process, and characterized by subduction and collision along two suture zones between three plates. The details of the orogenic processes, such as transition from rift system to plate-tectonic regime, from drifting to subduction and collision, and especially from point-contact initial collision through linear-contact collision to fully collisional orogeny, demonstrate that the Qinling was built up by dispersion, integration and accretion of a number of crustal blocks in Tethyan domain, and evolved under the influence of variation in coupling relationship between both ancient and modern mantle dynamics and lithosphere. | 张国伟 孟庆任 于在平 孙勇 周鼎武 郭安林 | 1996 | Science China Earth Sciences1996，39，3： | 28 |
| 14 | Progress in China's Unconventional Oil & Gas Exploration and Development and Theoretical Technologies显示文摘The new century has witnessed a strategic breakthrough in unconventional oil & gas.Hydrocarbon accumulated in micro-/nano-scale pore throat shale systems has become an important domain that could replace current oil & gas resources.Unconventional oil & gas plays an increasingly important role in our energy demand.Tight gas,CBM,heavy oil and asphaltic sand have served as a key domain of exploration & development,with tight oil becoming a 'bright spot' domain and shale gas becoming a 'hotspot' domain.China has made great breakthroughs in unconventional oil & gas resources,such as tight gas,shale gas,tight oil and CBM,and great progress in oil shale,gas hydrate,heavy oil and oil sand.China has an estimated(223-263)×10~8t of unconventional oil resources and(890-1260)×l0^(12)m^3 of gas resources.China has made a breakthrough for progress in unconventional oil & gas study.New progress achieved in fine-grained sedimentary studies related to continental open lacustrine basin large-scale shallow-water delta sand bodies,lacustrine basin central sandy clastic flow sediments and marine-continental fine-grained sediments provide a theoretical basis for the formation and distribution of basin central reservoir bodies.Great breakthroughs have been made in unconventional reservoir geology in respect of research methodology & technology,multi-scale data merging and physical simulation of formation conditions.Overall characterization of unconventional reservoirs via multi-method and multi-scale becomes increasingly popular and facilitates the rapid development of unconventional oil & gas geological theory,method and technology.The formation of innovative,continuous hydrocarbon accumulation theory,the establishment of the framework of the unconventional oil & gas geological theory system,and the determination of the implications,geological feature,formation mechanism,distribution rule and core technology of unconventional oil& gas geological study lays a theoretical foundation for extensive unconventional oil & gas exploration and development.Theories and technologies of unconventional oil & gas exploration and development developed rapidly,including some key evaluation techniques such as 'sweet spot zone' integrated evaluation and a six-property evaluation technique that uses hydrocarbon source,lithology,physical property,brittleness,hydrocarbon potential and stress anisotropy,and some key development &engineering technologies including micro-seismic monitoring,horizontal drilling & completion and 'factory-like' operation pattern, 'man-made reservoir' development,which have facilitated the innovative development of unconventional oil & gas.These breakthroughs define a new understanding in four aspects:①theoretical innovation;② key technologies;③ complete market mechanism and national policy support;and ④ well-developed ground infrastructure,which are significant for prolonging the life cycle of petroleum industry,accelerating the upgrade and development of theories and technologies and altering the global traditional energy structure. | ZOU Caineng YANG Zhi ZHU Rukai ZHANG Guosheng HOU Lianhua WU Songtao TAO Shizhen YUAN Xuanjun DONG Dazhong WANG Yuman WANG Lan HUANG Jinliang WANG Shufang | 2015 | Acta Geologica Sinica(English Edition)2015，89，3： | 27 |
| 15 | Nature of the Precambrian metamorphic blocks in the eastern segment of Central Tianshan:Constraint from geochronology and Nd isotopic geochemistry显示文摘Granitoid gneisses are widespread in Precambrian metamorphic blocks of eastern segment of the Central Tianshan Tectonic Zone, and they have intrusive contact relationships with their metamorphic sedimentary country rocks of Proterozoic Xingxingxia and Kawabulag groups. Zircon U-Pb ages from a granodioritic gneiss (IW11-1) and a parametamorphic schist (W05-9) are determined at the Weiya area. Euhedral prismatic zircons from the granodioritic gneiss (IW11-1) provide U-Pb isotopic discordia intercept ages of 1218±17 Ma and 426±26 Ma, respectively, and euhedral prismatic zircons from the parametamorphic schist (W05-9) display U-Pb isotopic discordia intercept ages of 1216±74 Ma and 290±15 Ma, respectively. A whole-rock Sm-Nd isotopic isochron is determined in augen granitoid gneiss samples at the Gang- gou-Kumishi area and we obtain the isochron age of 1142±120 Ma, and its ε Nd (t) = -4.3. These geochronological data suggest that these Precambrian metamorphic basement blocks within eastern segment of the Central Tianshan Tectonic Zone can be produced during 1140—1220 Ma, and occur a nearly homochronous metamorphism. Integrated to these geochronological data, Nd depleted mantle model ages (T DM ) and epsilon Nd(t) values of these granitoid gneiss samples indicate that they can derive from mixing in various scales both magmas from mantle and crust sources at a late Mesoproterozoic active continental margin tectonic environment. Similarity in geochronology, Sm-Nd isotopic geochemistry between Weiya-Xingxingxia, Pargangtag and Ganggou-Kumishi areas suggests that they could be a bigger uniform metamorphic basement block, which could be formed by the assembly of the supercontinent Rodinia and be separated by late geological processes. | LIU Shuwen,GUO Zhaojie,ZHANG Zhicheng,LI Qiugen & ZHENG Haifei The Key Laboratory of Orogenic Belts and Crustal Evolution,Ministry of Education,China School of Earth and Space Sciences,Peking University,Beijing 100871,China | 2004 | Science China Earth Sciences2004，47，12： | 26 |
| 16 | Adakite-type sodium-rich rocks in Awulale Mountain of west Tianshan:Significance for the vertical growth of continental crust显示文摘The sodium-rich dacites and albite porphyries of Permian in the Awulale Mountain of west Tianshan have unique chemical and trace element signatures identical to adakite. These intermediate-acidic igneous rocks are characterized by high Na2O, Al2O3 and Sr contents and high Sr/Y and La/Y ratios (>40 and >20, respectively), and low Y and Yb contents, and strong depletion in HREE, and positive Eu anomaly. The (143Nd/144Nd)i is in the range from0.51236 to 0.51248 and the εNd(t) is positive value (+0.79-+3.11); the (87Sr/86Sr)i is in the range from 0.7052 to 0.7054. These Nd and Sr isotopic composition features indicate that the source rocks of these adakite-type rocks are from a weakly depleted mantle, or a depleted mantle, but was contaminated by the crustal materials. These adakite-type rocks were most likely derived from the partial melting of new underplated basaltic rocks under the conditions of amphibo-lite to eclogite transition in the postcollisional environment of North Xinjiang during the Permian | XIONG Xiaolin ZHAO Zhenhua BAI Zhenghua MEI Houjun WANG Yixian WANG Qiang XU Jifeng Niu Hecai BAO Zhiwei | 2001 | Chinese Science Bulletin2001，46，10： | 25 |
| 17 | Cyclical one-way continental rupture-drift in the Tethyan evolution: Subduction-driven plate tectonics显示文摘Numerous continents have rifted and drifted away from Gondwana to repeatedly open ocean basins over the past-500 millionyears.These Gondwana-derived continents drifted towards and collided with components of the Eurasian continent to successively close the preexisting oceans between the two.Plate tectonics satisfactorily describes the continental drift from Gondwana to Eurasia but does not define the geodynamic mechanism of continuously rifting to collisions of continents in the Tethy an Realm.After reappraisal of geological records of the rift,collision and subduction initiation from the surface and various geophysical observations from depth,we propose that Eurasia-directed subducting oceanic slabs would have driven Tethyan system in the Phanerozoic.The Eurasia-directed subduction would have dragged the passive Gondwana margin to rift and drift northwards,giving birth to new oceans since the Paleozoic.The closure of preexisting oceans between the Gondwana-derived continents and Eurasia led to continental collisions,which would have induced the initiation of oceanic subduction in the Tethyan Realm.Multiple episodic switches between collision-subduction-rift repeatedly led to the separation of continental fragments from Gondwana and dragged them to drift towards Eurasia.The final disappearance of Neo-Tethy s would have induced collision of the Gondwana-derived continents with the Eurasian continent,giving rise to the Cenozoic Alpine-Zagros-Himalayan collisional system.Therefore,the Eurasia-directed oceanic subduction would have acted as a’one-way train’that successively transferred the ruptured Gondwana continental fragments in the south,into the terminal in the north.In this regard,the engine of this'Tethyan one-way train'is the negative buoyancy of subducting oceanic slabs. | Bo WAN Fuyuan WU Ling CHEN Liang ZHAO Xiaofeng LIANG Wenjiao XIAO Rixiang ZHU | 2019 | Science China Earth Sciences2019，62，12： | 21 |
| 18 | Stagnant lids and mantle overturns:Implications for Archaean tectonics, magmagenesis,crustal growth, mantle evolution, and the start of plate tectonics显示文摘The lower plate is the dominant agent in modern convergent margins characterized by active subduction,as negatively buoyant oceanic lithosphere sinks into the asthenosphere under its own weight.This is a strong plate-driving force because the slab-pull force is transmitted through the stiff sub-oceanic lithospheric mantle.As geological and geochemical data seem inconsistent with the existence of modernstyle ridges and arcs in the Archaean,a periodically-destabilized stagnant-lid crust system is proposed instead.Stagnant-lid intervals may correspond to periods of layered mantle convection where efficient cooling was restricted to the upper mantle,perturbing Earth's heat generation/loss balance,eventually triggering mantle overturns.Archaean basalts were derived from fertile mantle in overturn upwelling zones(OUZOs),which were larger and longer-lived than post-Archaean plumes.Early cratons/continents probably formed above OUZOs as large volumes of basalt and komatiite were delivered for protracted periods,allowing basal crustal cannibalism,garnetiferous crustal restite delamination,and coupled development of continental crust and sub-continental lithospheric mantle.Periodic mixing and rehomogenization during overturns retarded development of isotopically depleted MORB(mid-ocean ridge basalt)mantle.Only after the start of true subduction did sequestration of subducted slabs at the coremantle boundary lead to the development of the depleted MORB mantle source.During Archaean mantle overturns,pre-existing continents located above OUZOs would be strongly reworked;whereas OUZOdistal continents would drift in response to mantle currents.The leading edge of drifting Archaean continents would be convergent margins characterized by terrane accretion,imbrication,subcretion and anatexis of unsubductable oceanic lithosphere.As Earth cooled and the background oceanic lithosphere became denser and stiffer,there would be an increasing probability that oceanic crustal segments could founder in an organized way,producing a gradual evolution of pre-subduction convergent margins into modern-style active subduction systems around 2.5 Ga.Plate tectonics today is constituted of:(1)a continental drift system that started in the Early Archaean,driven by deep mantle currents pressing against the Archaean-age sub-continental lithospheric mantle keels that underlie Archaean cratons;(2)a subduction-driven system that started near the end of the Archaean. | Jean H.Bédard | 2018 | Geoscience Frontiers2018，9，1： | 21 |
| 19 | Continental hydrothermal sedimentary siliceous rock andgenesis of superlarge germanium(Ge)deposit hosted incoal:A study from the Lincang Ge deposit,Yunnan,China显示文摘There are abundant hydrothermal sedimentary structures and plant fragment fossils in the siliceous rocks from the Lincang Ge deposit. The major element compositions of these siliceous rocks are characterized by high content SiO2, low TiO2 and Al2O3concentrations, and low Al/(Al+Fe+Mn) ratios (0.010 on average). The siliceous rocks are distinctly enriched in Ge, Sb, As, W, and secondly enriched in Cs, U, Mo and Tl. Their total REE content are generally less than 1μg/g, LREE relatively concentrated, and the values of Eu anomaly and Ce anomaly vary from 0.452 to 5.141 and 0.997 to 1.174, respectively. Their NAS-normalized REE patterns are plain or left-inclined. The Oxygen isotope compositions of these siliceous rocks are similar to those of the hydrothermal siliceous sinter. The above characteristics, as well as the geological setting of the deposit, indicate these siliceous rocks formed in continental hydrothermal envi- ronment. As the interlayer or cliff of the Ge-rich coal seams, siliceous rocks tightly contacted with ore-body, and the contents of Ge in siliceous rocks vary from 5.6 to 360 μg/g (78 μg/g on aver- age). The Ge content increased in coal which close to the siliceous rocks. With the increase of Ge content, the typical trace element ratios (i.e., Ge/Ga, Nb/Ta and U/Th) and REE patterns of Ge-rich coal are more close to those of the siliceous rocks. The Ge concentrated in coal seams of the Lincang Ge deposit might be transported by the hydrothermal water, which demonstrated by the siliceous rocks, during the coal-forming processes. | QI Huawen1,2,HU Ruizhong1,SU Wenchao1,QI Liang1 & FENG Jiayi1 1.Key Laboratory of Ore Deposit Geochemistry,Chinese Academy of Sciences,Guiyang 550002,China 2.Department of Earth Sciences,Nanjing University,Nanjing 210093,China Correspondence should be addressed to Qi Huawen(email: qihuawen@sina.com) | 2004 | Science China Earth Sciences2004，47，11： | 18 |
| 20 | GRAVITY-DRIVEN SEDIMENTATION ON THE NORTHWESTERN CONTINENTAL SLOPE IN THE SOUTH CHINA SEA:RESULTS FROM HIGH-RESOLUTION SEISMIC DATA AND PISTON CORES显示文摘A distinct echo-character was assigned to sedimentation processes, which were then verified using data from surface sediment samples and piston cores. of echo types on the continental slope perfectly reflecting both sediment erosion and deposition, four edimentary types have been recognized:(1) submarine clides distributed on the shelfbreak and characterized by high silt and water conten, loose struture, poor consolidation and low shearing strength; (2) slumps occurring on the shelfbreak, middle slope channel and reef margin near Dongsha Islands, but having different origins; (3) debris flow occurring either in sea areas around Dongsha Atoll, or on the continental slope’s three channels, where the transparent debris flow deposits often overlie or abruptly truncate highly stratified hemipelagic sediments;are of limited to local extent, ranging from a few square kilometers to hundreds of square kilometers in area; but on the lowr slope, usually occur as 1000 km2, about 100 km2 individual complexes; and (4) turbidites, limited on the continental slope; are occurring as migrating waves of sediments at the the of the slope, and are rhythmically-bedded, coarse-grained. Their migration is a result of overbank flow downslope through the submarine channel at the west. The slope faces are dominated by mass wasting deposition, and a few turbidite current sediments. As wasting is an important process. Some debris flow eomplexes on the west are buried by well-stratified confomable sediments, whereas others on the east appear on the present seafloor and therefore are relatively recent. | 吴时国 | 1999 | Chinese Journal of Oceanology and Limnology1999，17，2： | 18 |
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