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A perspective view on ultrahigh-pressure metamorphism and continental collision in the Dabie-Sulu orogenic belt

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Chinese sci.nce Bulletin 2008年第20期53卷 3081-3104页

作者： ZHENG YongFei CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

The study of continental deep-subduction has been one of the forefront and core subjects to advance the plate tectonics theory in the twenty-first century. The Dabie-Sulu orogenic belt in China crops out the largest lithotectonic unit containing ultrahigh-pressure metamorphic rocks in the world. Much of our understanding of the world's most enigmatic processes in continental deep-subduction zones has been deduced from various records in the Dabie-Sulu rocks. By taking these rocks as the natural laboratory, earth sci.ntists have made seminal contributions to understanding of ultrahigh-pressure metamorphism and continental collision. This paper outlines twelve aspects of outstanding progress, including spatial distribution of the UHP metamorphic rocks, timing of the UHP metamorphism, timescale of the UHP metamorphism, the protolith nature of deeply subducted continental crust, subduction erosion and crustal detachment during continental collision, the possible dept.s of continental subduction, fluid activity in the continental deep-subduction zone, partial melting during continental collision, element mobility in continental deep-subduction zone, recycling of subducted continental crust, geodynamic mechanism of postcollisional magmatism, and lithospheric architecture of collision orogen. Some intriguing questions and directions are also proposed for future studies.

关键词：大陆岩石圈地壳超高压变质作用切向压缩力

The Nd-Sr isotope study of Mesozoic granitoids in Jiangxi Province

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Chinese sci.nce Bulletin 1999年第15期44卷 1427-1431页

作者： Weizhou Shen Hongfei Ling Wuxian Li Dezi Wang Xuan Huang Jun Pan Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China Chinese Acad sci Inst Geol Beijing 100029 Peoples R China

Nd-Sr isotopic compositions of 12 Mesozoic granitoids from Jiangxi Province have been reported. They show loe-εND（-13.8—- 8.3）, high-lsr（0.71069—0.73981） and old tDM （2087—1635 Ma）. Comparison between the Sm-Nd isotopic compositions of the granitoids and those of the basement metamorphic rocks suggests that these granitoids were mainly derived from the metasedimentary rocks. There is an east-west trend Mesozoic granitoid zone with lowtDM from S. Jiangxi to S. Fujian. The origin of these granites was preliminarily discussed.

关键词： Nd-Sr isotopic compositions material source low-tDM zone Mesozoic granitoids Jiangxi Province.

Origin of ore-forming fluids of the Dachang Sn-polymetallic ore deposit: Evidence from helium isotopes

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Chinese sci.nce Bulletin 2002年第12期47卷 1041-1045页

作者： Kuidong Zhao Shaoyong Jiang Hongquan Xiao Pei Ni Nanjing Univ Dept Earth Sci State Key Lab Mineral Deposits Res Nanjing 210093 Peoples R China

The ore genesis model for the Dachang Sn-polymetallic ore deposit has long been in dispute, and the major debate focuses on whether the stratiform and massive orebodies formed during the Yanshanian magmatic-hydro-thermal event or they were products of Devonian syn-sedi-mentary exhalative-hydrothermal event. This note presents new helium isotope data from fluid inclusions of four pyrites and one fluorite. The pyrites were collected from the stratiform and massive orebodies in the deposit, and their 3He/4He ratios are significantly higher than 1, ranging from 1.7 to 2.5 Ra, which indicates a mantle component in the responsible hydrothermal fluids. It is suggested that the ore-forming fluids were a mixture of deep circulating seawater and a mantle-derived fluid, which are similar to many of those modern submarine hydrothermal fluids. In contrast, the fluorite, collected from a granite-related hydrothermal vein in the deposit, shows a low 3He/4He ratio of 0.7 Ra, which indicates no mantle component

关键词： He and Ar isotopes crustal fluid mantle fluid massive sulfide deposit Dachang Sn-polymetallic deposit.

Helium isotope compositions of Machangqing copper deposit in western Yunnan, China

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Chinese sci.nce Bulletin 1998年第1期43卷 69-72页

作者： Ruizhong Hu G. Turner P. G. Burnard Xianwu Bi Chinese Acad sci Inst Geochem Guiyang 550002 Peoples R China Univ Manchester Dept Earth Sci Manchester M13 9PL Lancs England

Helium isotopic composition of inclusion fluid in pyrites from Machangqing copper deposit, China, has been measured. The measurements, with 3He/ 4He ratios ranging from 0 46-2 08 Ra, indicate that the helium in ore_forming fluid is a mixture of crust and mantle, and are consistent with the fact that the parental magma responsible for the formation of ore_forming fluid of the deposit is of crust_mantle provenance.

关键词： helium isotope copper deposit western Yunnan.

Two granitic plutons in Central Western Kunlun Belt: Their ages and possible sources

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Chinese sci.nce Bulletin 1999年第19期44卷 1807-1810页

作者： Chao Yuan Min Sun Jiliang Li Univ Hong Kong Dept Earth Sci Hong Kong Peoples R China Chinese Acad sci Inst Geol Beijing 100029 Peoples R China

Geochronological and isotope studies have been carried out for two important plutons in the Central Western Kunlun Belt. U-Pb single grain zircon dating results show that the North Kudi Pluton (404 Ma) was produced near the end of Caledonian; whereas the previously labeled Hercynian Arkarz Mountain Pluton (215 Ma) is either an Indosinian pluton or a product

关键词： granitic pluton. Central Western Kunlun Belt.

Petrogenesis of Aoyougou high-silica adakite in the North Qilian orogen,NW China:Evidence for decompression melting of oceanic slab

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Chinese sci.nce Bulletin 2012年第22期57卷 2289-2301页

作者： YuXiao Chen XiaoHong Xia ShuGuang Song Peking Univ Sch Earth & Space Sci MOE Key Lab Orogen Belts & Crustal Evolut Beijing 100871 Peoples R China

A trondhjemitic body occurs in the Aoyougou area,the western part of the North Qilian *** is geochemically characterized by high SiO 2,Na 2 O (high Na/K),elevated Sr/Y and (La/Yb) N,positive Sr anomaly,relatively enriched large ion lithophile elements (LILEs) and light rare earth elements (LREEs),and depleted Nb,Ta,Ti,resembling the high-silica *** U-Pb SHRIMP dating yields a weighted mean age of 438±3 *** age is significantly younger than eclogitization ages of 460-490 Ma in the North Qilian orogen,suggesting that formation of the adakite postdates the subduction of oceanic crust in association with closure of the ancient Qilian ***-rock Sr and Nd isotopic analyses give initial ratios of I Sr =0.7044 0.7047 and Nd (t)=3.0 4.1,indicating that they are derived from partial melting of the juvenile oceanic *** view of the tectonic evolution of the North Qilian orogen,the high-silica adakite was probably derived from decompression melting of the exhumed eclogite at the dept. of ～60 km.

关键词：北祁连造山带大洋地壳部分熔融埃达克岩稀土元素地球化学特征高硅中国西北减压

Paleomagnetism of early Triassic Daye Formation and its tectonic implications

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Chinese sci.nce Bulletin 1999年第5期44卷 412-418页

作者： Zhongyue Shen Dajun Fang Penyang Wang Xiaodong Tan Zhaolian Wang Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China Daqing Petr Inst Daqing 163000 Peoples R China

The new paleomagnetic data of the early Triassic Daye Formation from Hubei Province are reported. The ChRM passes consistency test and reversal test. Two magnetic components were isolated with principal component analysis （PCA）. Component B is a ChRM and component A was acquired by remagnetization during lndosinian cycle. Rock magnetic study shows that the carrier is dominantly detrital magnetite. According to the data, in conjunction with recently published Triassic paleornagnetic results, mean paleopole of the Triassic Yangtze Block is calculated as 30.3°N, 198.4°E, α95 = 9.2°.Distribution of all Triassic declinations indicates obviously local rotation in the mid-Yangtze areas,which results in consistence of the declinations with fold axes. By comparison with Triassic paleomagnetic data in the South China Block and some of geological evidence, it is inferred that the timing of the suture between the Yangtze Block and the South China Block is earlier in western part than in eastern part in the

关键词： Yangtze Block Triassic paleomagnetism collision orogeny.

A CLASS OF r-POINT (r+1)ST-ORDER A-STABLE ONE-BLOCK METHODS WITH DAMPING AT THE INFINITE POINT

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Numerical Mathematics A Journal of Chinese Universities(English Series) 2002年第2期11卷 161-178页

作者： Zhao Shuangsuo(赵双锁) Zhang Guofeng(张国风) dept. of Inform. and Comput. sci. The Second Northwest University for Nationalities Yinchunan 750021 PRC Dept. of Math. Lanzhou University Lanzhou 73000 PRC

This paper presents a class of r-point (r+1)st-order A-stable one-block methods with damping at the infinite point (DIAOB r,r+1 ). Under the conditions of the same order, A-stability, operation count (at each iterative step) and storage space are the same as the methods in , the methods in the paper improve the stability in a neighborhood at the infinite point. And, by using the OOPI method , it possesses much faster rate of convergence for solving systems of nonlinear equations produced by the DIAOB r,r+1 .

关键词： one-block method, stiff problem, A-stability, damping at infinite point.

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冀东晚古生代东湾子岩体的岩石成因研究

岩石学报 2009年第8期25卷 1975-1988页

作者：马旭陈斌牛晓露 Peking Univ MOE Sch Earth & Space Sci Key Lab Orogen Belts & Crustal Evolut Beijing 100871 Peoples R China

冀东晚古生代东湾子岩体由角闪石岩、少量辉石岩和辉长岩组成。典型的堆晶结构、全岩和镁铁质矿物(透辉石、角闪石)的上凸型稀土分布模式、相容元素含量低且变化范围大(如:角闪石岩中V=296×10^(-6)～673×10^(-6))的特征表明了岩体的... 详细信息

冀东晚古生代东湾子岩体由角闪石岩、少量辉石岩和辉长岩组成。典型的堆晶结构、全岩和镁铁质矿物(透辉石、角闪石)的上凸型稀土分布模式、相容元素含量低且变化范围大(如:角闪石岩中V=296×10^(-6)～673×10^(-6))的特征表明了岩体的堆晶成因。计算得到的与辉石岩中的透辉石相平衡的熔体具有很高的稀土含量,轻重稀土分馏较为明显,富集大离子亲石元素(如:Sr,Ba,K),亏损高场强元素(如:Nb,Zr,Ti),具有典型的弧岩浆特征。透辉石和角闪石的矿物成分也具有弧岩浆的特征。高钙透辉石、大量的角闪石与黑云母的存在说明母岩浆富水。透辉石在高P_(H_2O)的状态下与熔体反应,生成角闪石的结构特征也证明了这一点。结合岩体的球化学特征,认为岩浆来源于富集的含有角闪石的尖晶石橄榄岩的部分熔融,母岩浆具有富水的特征(>3%)。考虑到岩体形成时代(～300Ma;Zhao et al.,2007)和地质背景,认为东湾子岩体与位于华北北缘的其它晚石炭-早二叠世的岩体形成于同一构造背景下,都是晚古生代时期古亚洲洋向华北板块之下俯冲的产物。

关键词：冀东晚古生代岩体岩石成因 Late Paleozoic 角闪石岩透辉石结构特征母岩浆 partial melting 高场强元素轻重稀土分馏尖晶石橄榄岩辉石岩 North China depletion 早二叠世元素含量岩浆来源形成时代