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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Laicheng Miao~(a*),Fuqin Zhang~a,Weiming Fan~a and Dunyi Liu~b a Institute of Geology and Geophysics,chinese academy of sciences,{3.,china b {3. shrimp Centre,Institute of Geology, chinese academy of geological sciences,{3.,china

We propose that inherited Neoproterozoic zircons in Mesozoic igneous rocks from the eastern portion of the North china craton(NCC) were initially derived from the Yangtze/South china block,rather than from the NCC *** mechanism that introduced these zircons into the NCC was likely tectonic underplating during Triassic continental subduction/collision of the Yangtze block beneath the *** addition of abundant crustal materials represented by the exotic zircons,probably along the Moho or weak interfaces within the NCC crust,led to the crustal thickening of the *** sialic materials contributed significantly to the Mesozoic igneous rocks, either as source rocks or as contaminants of magmas generated during an extensional environment following crustal *** thickening was spatially linked to lithospheric thinning,with both occurring mainly in the eastern segment of the NCC, suggestive of an intrinsic relationship between thickening and thinning events during Mesozoic evolution of the NCC.

关键词： inherited zircons felsic igneous rocks underplating of the NCC Mesozoic magmatism North china craton

Constraints on the Archean atmospheric oxygen and sulfur cycle from mass-independent sulfur records from Anshan-Benxi BIFs, Liaoning Province, china

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Science china Earth sciences 2007年第10期50卷 1471-1478页

作者： HOU KeJun1,2, LI YanHe1,2? & WAN DeFang1,2 1 Key Laboratory of Metallogeny and Mineral Resource Assessment, Institute of Mineral Resource, chinese academy of geological sciences (CAGS), beijing 100037, china 2 Key Laboratory of {3. Geology, CAGS, beijing 100037, china Key Laboratory of Metallogeny and Mineral Resource Assessment Institute of Mineral Resource Chinese Academy of Geological Sciences (CAGS) Beijing 100037 China Key Laboratory of isotope Geology CAGS Beijing 100037 China

The Archean atmospheric oxygen concentration and sulfur cycle was long debated. The banded iron formation (BIF) is a special type of the sedimentary formation, which has truly recorded the atmospheric and oceanic conditions at that time. In this study, the composition of multiple sulfur isotope (δ 3.S/δ 3.S/δ 3.S) for sulfides bedded in the Archean (~2.7 Ga) BIFs, in Anshan-Benxi area of Liaoning Province has been measured. The value of △3.S varies from -0.89‰ to +1.21‰, which shows very obvious mass-independent fractionation (MIF) signatures. These non-zero △3.S values indicate that the Archean sulfur cycles are different from what it is today, which have been deeply influenced by gas phase photochemical reactions. Algoma-type BIFs which are closely related to the volcanic activity have negative △3.S value, however, Superior-type BIFs which are far away from the volcanic center have positive △3.S value. The δ 3.S varies in a large range from -22.0‰ to +11.8‰, which indicates that the bacteria reduction activity has already existed at that time, and that the oceanic sulfate concentration has at least reached 1 mmol/L in local areas. Combined with the contemporaneous existence of the hematite, magnetite and the occurrence and preservation of the sulfur MIF, it can be inferred that the Archean atmospheric oxygen level must be at 10-2―10-3.of the present atmospheric level (PAL).

关键词： sulfur mass-independent fractionation, Anshan-Benxi area, BIF, Archean atmospheric oxygen level, Archean sulfur cycle

Depth of coesite-bearing eclogite formation, Dabie UHPM zone, china, based on structure stress correction

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Depth of coesite-bearing eclogite formation, Dabie UHPM zone...

地壳深部压力状态与地质作用学术研讨会

作者： Lü Guxian, Chen Jing, Ding Tiping, Li Xiaobo, Wang Fangzheng and Liu Ruixun Institute of Geomechanics, beijing, 100081, china Electron Microscopy Laboratory, Peking University, beijing, 100871, china Open Research Laboratory of isotope Geology, chinese academy of geological sciences, beijing 100037, china Institute of geological Information, beijing, 100037, china {12. University of Geo{13., Wuhan, Hubei, 43.074, china Department of Geology, Peking University, beijing, 100871, china

＜正＞ Plastic deformation of garnet in coesite-bearing eclogite, quartz eclogite and garnet amphibolite of the ultra-high pressure metamorphic（UHPM） complex in Yingshan County, Dabie Mountains, has been studied by transmission electron microscopy （TEM）. Garnets have undergone ductile deformation under eclogite and amphibolite facies conditions. Garnet microstructures vary greatly with the dislocation density of the garnet being lower in coesite-bearing eclogite is than that in garnel *** generated by strong tectonic movement were an important component of the total pressure causing the formation of eclogite in the Dabie UHPM zone. The three-dimensional tectonic principal stresses and additional tectonic stress-induced hydrostatic pressure [Ps=-（σ1+σ2+σ3./3. are reconstructed according to the differential stress and strain ratio （a） of garnet in minor coesite-bearing eclogite of Yingshan county. Then the gravity-induced hydrostatic pressure （PG） is calculated through P minus PS, where P is estimated to be 2.8 GPa based on the quartz-coesite geobarmeter. Therefore, the thickness of the rock column overlying the coesite-bearing eclogite in Yingshan county is determined to be ≥2.09-3..11 km. this estimation is significantly different from the previous estimation of ≥100km obtained solely by considering the weight/specific weight ratio （W/SW）.It gives also a proper explanation to the puzzle that no tracer of addition of mantle-derived material has been found in the Dabie UHPM zone during the process of UHPM, although a number of researches claim that this process was taking place at depth of the mantle （≥100 km） . It is concluded that attention should be paid to the additional tectonic stress-induced hydrostatic pressure in the study of UHPM zones.

关键词： Dabie UHPM zone formation depth additional tectonic stress-induced hydrostatic pressure coesite-bearing eclogite tectonic physicochemistry plastic deformation garnet

Geochronology and geochemistry of the Hegenshan ophiolitic complex:Implications for late-stage tectonic evolution of the Inner Mongolia-Daxinganling Orogenic Belt,china

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Geochronology and geochemistry of the Hegenshan ophiolitic c...

中国科学院地质与地球物理研究所2008学术年会

作者： Laicheng Miao~(a,*),Weiming Fan~a,Dunyi Liu~b,Fuqin Zhang~a,Yuruo Shi~b,Feng Guo~c a Institute of Geology and Geophysics,chinese academy of sciences,{3. 100029,china b {3. shrimp Center,Institute of Geology,chinese academy of geological sciences,{3. {12.,china c Guangzhou Institute of Geochemistry,chinese academy of sciences,Guangzhou 510640,china

The Hegenshan ophiolite in the Inner Mongolian-Daxinganling Orogenic Belt(IMDOB),northern china,consists of several discontinuous blocks composed dominantly of serpentinized ultramafic rocks with subordinate cumulate gabbros,mafic lavas and dikes, intruded by younger granodiorite *** ultramafic rocks are highly depleted,serpentinized harzburgites with minor dunite,characterized by relative enrichment in large ion lithophile elements(LILE,e.g.,Ba and Rb) and light rare earth elements(LREE).They are interpreted to be oceanic mantle that has undergone extensive melt extraction and variable degrees of *** cumulate rocks consist mainly of gabbro and troctolite with LREE-depleted chondrite-normalized REE patterns showing significant positive Eu *** are enriched in LILE,depleted in Nb,and have high positiveε(t)(+8 to +11),suggesting derivation from a subduction-modified N-MORB-like *** gabbros and mafic dikes have essentially the same age(295±15 and 298±9 Ma,respectively). The mafic dikes have flat to LREE-depleted,chondrite-normalized REE patterns,are depleted in Nb,enriched in LILE and have NMORB-type Nd isotopic signatures(ε(t)=+8.1 to +10).The mafic lavas,erupted at 293.1 Ma,can be divided into two groups;one composed of strongly deformed metabasalts similar in chemical and Nd-Sr isotopic compositions to the mafic dikes,and the other composed of undeformed and unmetamorphosed basalts with oceanic island basalt(OIB)-like trace element signatures and Nd isotopic *** granodiorite dikes,which were intruded at 244±4 Ma,have LREE-enriched,chondrite-normalized REE patterns with no Eu *** abnormally highε(t) values(+6.3.to +6.8) and low I(0.70412.to 0.70450) suggest formation from melts derived from thickened oceanic crust during or shortly after closure of the Paleo-Asian *** structure,lithology and geochemistry of the Hegenshan ophiolite suggest that it is a Cordilleran-type body formed in a supra-subduction

关键词： Ophiolite Geochronology Geochemistry Late Paleozoic Inner mongolia

Tectonic setting of the Helong Block:Implications for the northern boundary of the eastern North china Craton

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Science china Earth sciences 2005年第10期48卷 1599-1612页

作者： ZHANG Yanbin1, WU Fuyuan1, ZHAI Mingguo1 & LU Xiaoping1,2 1. Institute of Geology and Geophysics, chinese academy of sciences, P.O. Box 9825, {3. 100029, china 2. Regional geological and Mineral Resources Survey of Jilin Province, Changchun 13.062, china chinese academy of sciences Regional geological and Mineral Resources Survey of Jilin Province

LA-ICP-MS zircon U-Pb dating indicates that the Bailiping granitic pluton was em-placed during Late Paleozoic to Early Cretaceous (285―116 Ma) by four distinct magmatic epi-sodes, arguing against the previous thought that the Bailiping granites were emplaced during Archean, Proterozoic or Early Paleozoic. It is suggested that the so-called Archean Jincheng-dong granite-greenstone belt, mainly composed of Bailiping granites, should be broken down. Sr-Nd isotopic compositions of the Bailiping granites are similar to those of the Phanerozoic granites in the Xing’an-Mongolian orogenic belt, suggesting that their parental magmas were mainly derived from a juvenile crust with some contamination of ancient crustal materials during magma rising and/or emplacement. Therefore, the basement of the Helong Block is similar to that in the northern Xing’an-Mongolian Orogenic Belt, but different from that of the North china Craton. It is proposed that the Archean Jinchengdong complex in this area is probably an exotic slice from the North china Craton, which indicates that the Fu’erhe-Gudonghe Fault, located in northern part of the Helong area, is not the boundary between the North china Craton and the Xing’an-Mongolian Orogenic Belt. The possible boundary should be located further southward more than 50 km and near the Baitoushan volcano.

关键词： LA-ICPMS ziron U-Pb dating, Bailiping complex, Helong Block, North china Craton, Sr-Nd isotope.

Tectono-chronologic constraints on a Mesozoic slip and thrust belt in the eastern Jiaodong Peninsula

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Science china Earth sciences 2007年第1期50卷 25-32页

作者： ZHANG HongYuan1,2, HOU QuanLin3.& CAO DaiYong 4 1 Institute of Geology, chinese academy of geological sciences, beijing 100037, china 2 State Key Laboratory of {3. Processes and Mineral Resources, china University of Geosciences, beijing 100083. china 3.Graduate School of china Acacemy of sciences, beijing 10003., china 4 Key Laboratory of Coal Resources (CUMT), Ministry of Education, beijing 100083. china Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Graduate School of china Acacemy of sciences Beijing 100039 China Key Laboratory of Coal Resources (CUMT) Ministry of Education Beijing 100083 China

A major slip and thrust belt within the eastern Jiaodong Peninsula is located at the eastern terminal of the Qinling-Dabie-Sulu orogenic belt between the Sino-Korea Block and Yangtze Block. Although a lot of isotope chronologic data have been obtained regionally, little structural chronological research has been conducted in this region and this paper corrects that. Syn-deformational minerals were system-atically selected from samples of the NE-ENE trending transpressional shear zones and transpres-sional nappes and carefully analysed using 40Ar/3.Ar methods. Two tectonic events were defined with the first event resulting from early movement of transpressional nappes around 190 Ma ago. This ac-cords with the period of syn-orogenic sinistral slip of the Tan-Lu faults and clockwise shear in the Eastern Qinling-Tongbaishan part of the Qinling-Dabie-Sulu orogenic belt. The second event involved strikeslip thrust movement of deep shear zones between 13.Ma and 12.Ma. This resulted from the onset of Mesozoic tectonic conversion in the eastern Jiaodong Peninsula. The sinistral strikeslip-thrusting in Jiaodong Peninsula and the extensional tectonism (toward ESE) in Liaodong Peninsula probably resulted in the clockwise rotation of Korea Peninsula in late Mesozoic.

关键词： the eastern Jiaodong Peninsula tectono-chronology 40Ar/3.Ar strikeslip and thrust belt.

Provenance of Carboniferous sedimentary rocks in the northern margin of Dabie Mountains,central china and the tectonic significance:constraints from trace elements,mineral chemistry and shrimp dating of zircons

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Provenance of Carboniferous sedimentary rocks in the norther...

中国科学院地质与地球物理研究所2004学术年会

作者： Renwei Li~(a,*),Shuangying Li~b,Fuquan Jin~b,Yusheng Wan~c,Shukun Zhang~d a Institute of Geology and Geophysics,chinese academy of sciences,{3. 100029,china b Department of Resource and Environment sciences,Hefei Industrial University,Hefei 23.026,china c shrimp II Laboratory,Institute of Geology,chinese geological academy of sciences.{3. {13.,china d Institute of Geomechanics,chinese geological academy of sciences,{3. 100081,china

A suite of slightly metamorphosed Carboniferous sedimentary strata occurs in the northern margin of the Dabie Mountains, central *** consists,in ascending order,of the upper Huayuanqiang Formation(C),the Yangshan Formation(C),the Daorenchong Formation(C),the most widely distributed Huyoufang Formation(C) and the Yangxiaozhuang Formation (C).The provenance of the Carboniferous sedimentary rocks is constrained by the integration of trace elements,detrital mineral chemistry and sensitive high resolution ion microprobe(shrimp) dating of detrital zircons,which can help to understand the connection between the provenance and the Paleozoic tectonic evolution of the Qinling-Dabie *** trace element compositions indicate that the source terrain was probably a continental island *** tourmalines were mainly derived from aluminous and Al-poor metapelites and metapsammites,and some are sourced from Li-poor granitoids, pegmatites and *** garnets,found only in the uppermost Huyoufang Formation,are almandine and Mn-almandine garnets,indicating probable sources mainly from garnetiferous schists,and partly from granitoid *** detrital white Kmicas are muscovitic in the Huayuanqiang,Daorenchong and Huyoufang Formations,and phengitic with Si contents(p.f.u.) from 3.20 up to max.3.47-3.53.in the uppermost Huyoufang and the Yangxiaozhuang Formations,a meta-sedimentary source. Major components in the detrital zircon age structure for the Huyoufang Formation range from 506 to 3.3.Ma,centering on - 400 and - 480 Ma,which is characteristic of the Qinling and Eriangping Groups in the Qinling and Tongbai Mountains, central ***,the major source of the Carboniferous sedimentary rocks in the northern margin of Dabie Mountains was from the southern margin of the Sino-Korean Craton represented by the Qinling and Eriangping *** source area was an island-arc system during the Early Paleozoic that collided with the Sino-Korea plate towards the e

关键词： Provenance Detrital minerals Trace elements Zircon geochronology Carboniferous Dabie Mountains Central china

U-Pb zircon age dating of a rapakivi granite batholith in Rangnim massif,North Korea

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U-Pb zircon age dating of a rapakivi granite batholith in Ra...

中国科学院地质与地球物理研究所2007学术年会

作者： MINGGUO ZHAI~(*+++§),JINGHUI GUO~(*+),PENG PENG~(*+) & BO HU~(*+) *Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chines academy of sciences, beijing 100029,{3. +beijing shrimp Center,chinese academy of geological sciences,beijing 100037,{3. ++ State Key Laboratory of Lithosphere Tectonic Evolution,beijing 100029,{3.

Rapakivi granites and several small leucogabbroic and gabbroic bodies are located in the Rangnim Massif,North *** largest batholith in the Myohyang Mountains covers an area of 3.0 km and was intruded into Precambrian metamorphosed *** has a shrimp U-Pb zircon weighted mean Pb/Pb age of 1861±7 *** country rocks of rapakivi granites are Neoarchaean orthogneisses and Palaeo-Mesoproterozoic graphite-bearing metasedimentary rocks of granulite facies,and they are similar to those of the rapakivi granites and anorthosites exposed in South Korea and in the North china *** conclude that the three massifs in the Korean Peninsula commonly record an identical Palaeo-Mesoproterozoic anorogenic magmatic event,indicating that they have a common Precambrian basement with the North china Craton.

关键词： Rapakivi granite shrimp U-Pb zircon age Rangnim Massif North Korea

Zircon shrimp U-Pb ages of the“Xinghuadukou Group”in Hanjiayuanzi and Xinlin areas and the“Zhalantun Group”in Inner Mongolia,Da Hinggan Mountains

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Zircon SHRIMP U-Pb ages of the“Xinghuadukou Group”in Hanji...

中国科学院地质与地球物理研究所2007学术年会

作者： MIAO LaiCheng~(1+),LIU DunYi~2,ZHANG FuQin~1,FAN WeiMing~1,SHI YuRuo~2 & XIE HangQiang~1 1 Institute of Geology and Geophysics,chinese academy of sciences,{3. 100029,china 2 {3. shrimp Center,Institute of Geology,chinese academy of geological sciences,{3. {12.,china

A report is presented of shrimp zircon U-Pb dating data of meta-igneous and meta-sedimentary rocks of the Xinghuadukou Group(Xinlin-Hanjiayuanzi area,Heilongjiang Province) and meta-volcanic rocks of the Zhalantun Group(Zhalantun district,Inner Mongolia).The shrimp analyses show that the meta-igneous rocks from the Xinghuadukou Group formed at 506±10 -547±46 Ma,belonging to Early-Middle Precambrian,whereas the meta-sedimentary rocks yielded detrital zircons,with ages of 1.0 - 1.2,1.6 - 1.8 and 2.5 - 2.6 Ga,indicative of deposition age at least3.*** data suggest that both the Xinghuadukou and Zhalantun Groups formed during Cambrian and/or Neoproterozoic time,rather than Paleoproterozoic time as previously *** Precambrian inherited zircons in the meta-igneous rocks and numerous Precambrian detrital zircons in the meta-sedimentary rocks imply that these rocks were formed proximal to older *** is inferred that the Xinghuadukou and Zhalantun Groups represent Cambrian and/or Neoproterozoic volcano -sedimentary sequences formed in an active continental margin setting.

关键词： zircon shrimp metamorphic rock Xinghuadukou Group Zhalantun Group Da Hinggan Mountains

A Study of the Rhenium-Osmium Geochronometry of Molybdenites

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Acta Geologica Sinica(English Edition) 1995年第2期69卷 171-181页

作者： Du Andao, He Hongliao, Yin Ningwan, Zou Xiaoqiu,Sun Yali, Sun Dezhong, Chen Shaozhen and Qu Wenjun Institute of Rock and Mineral Analysis, chinese academy of geological sciences, beijing Fei Zhenbi Institute of Rock and Mineral Analysis Chinese Academy of Geological Sciences Beijing

This study deals with the first application of the isotope dilution - inductively coupled plasma mass spectrometry in the rhenium-osmium geochronometry in china. The chemical separation procedure included decomposition of samples by means of alkali fusion, extraction of rhenium by acetone and extraction of osmium by distillation. The recovery of both elements in the entire process was more than 90% . The blanks of analyses were 0.07 ng for rhenium and 0.01 ng for 187Os. The mineralization ages of molybdenites from four molybdenum deposits in china were determined by using this method, with a precision (2σ)of about ±3. . These results agree satisfactorily with their {3. backgrounds. The Re-Os method can directly determine ages of metal deposits and reflect the true ages more reliably than other dating methods that only determine the ages of country rocks from which mineralization ages are inferred. As many hydrothermal sulphide deposits usually contain molybdenites, this method has bright prospects of wide application.

关键词： rhenium-osmium method molybdenite ore-forming age determination isotope dilution inductively coupled plasma source mass spectrometry