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Cassiterite U-Pb Date of the Yangbin Porphyry Tin Deposit in Zhejiang and its Geological Significance 被引量:3
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作者 LI Qianzhen YAO Junming ZHANG Rongqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第6期2454-2456,共3页
Objective The Yangbin porphyry tin deposit in Taishun County of Zhejiang Province is one of the few porphyry-type tin deposits in South China, which is located in the middle portion of the Mesozoic volcanic active bel... Objective The Yangbin porphyry tin deposit in Taishun County of Zhejiang Province is one of the few porphyry-type tin deposits in South China, which is located in the middle portion of the Mesozoic volcanic active belt on the southeastern coast of China. The Yangbin granite porphyry is closely related to the tin mineralization in this region. Based on petrologic and Sr-Nd-Pb isotopic 展开更多
关键词 Pb cassiterite u-pb Date of the Yangbin Porphyry Tin Deposit in Zhejiang and its Geological Significance
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An Overview on the Composition and Age of Upper Crust of Proto-Tethyan Lajishan Intra-oceanic Arc,NE Tibet Plateau
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作者 FU Changlei HE Xiaohu +5 位作者 YAN Zhen Jonathan CAITCHISON XIAO Wenjiao WANG Bingzhang LI Wufu LI Yusen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期285-302,共18页
Identification and anatomy of oceanic arcs within ancient orogenic belt are significant for better understanding the tectonic framework and closure process of paleo-ocean basin.This article summarizes the geological,g... Identification and anatomy of oceanic arcs within ancient orogenic belt are significant for better understanding the tectonic framework and closure process of paleo-ocean basin.This article summarizes the geological,geochemical,and geochronological characteristics of upper crust of Proto-Tethyan Lajishan intra-oceanic arc and provides new data to constrain the subduction evolution of the South Qilian Ocean.The intra-oceanic arc volcanic rocks,including intermediate-mafic lava,breccia,tuff,and minor felsic rocks,are distributed along southern part of the Lajishan ophiolite belt.Geochemical and isotopic compositions indicate that the intermediate-mafic lava were originated from depleted mantle contaminated by sediment melts or hydrous fluids,whereas the felsic rocks were likely generated by partial melting of juvenile mafic crust in intra-oceanic arc setting.Zircons from felsic rocks yield consistent and concordant ages ranging from 506 to 523 Ma,suggesting these volcanic rocks represent the relicts of upper crust of the Cambrian intra-oceanic arc.Combined with the Cambrian forearc ophiolite and accretionary complex,we suggest that the Cambrian intra-oceanic arc in the Lajishan ophiolite belt is belonging to the intra-oceanic arc system which was generated by south-directed subduction in the South Qilian Ocean at a relatively short interval between approximately 530 and 480 Ma. 展开更多
关键词 volcanic rocks intra-oceanic arc u-pb age Lajishan ophiolite belt South Qilian Ocean Proto-Tethyan realm
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Geochemistry and SHRIMP Zircon U-Pb Age of Post-Collisional Granites in the Southwest Tianshan Orogenic Belt of China:Examples from the Heiyingshan and Laohutai Plutons 被引量:19
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作者 LONG Lingli GAO Jun +5 位作者 WANG Jingbin QIAN Qing XIONG Xianming WANG Yuwang WANG Lijuan GAO Liming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期415-424,共10页
The Heiyingshan granite and the Laohutai granite plutons exposed in the Southwest Tianshan resemble A-type granites geochemically. Analysis shows that the both are ferron calc-alkalic peraluminous or ferron alkali-cal... The Heiyingshan granite and the Laohutai granite plutons exposed in the Southwest Tianshan resemble A-type granites geochemically. Analysis shows that the both are ferron calc-alkalic peraluminous or ferron alkali-calcic peraluminous with a relatively high concentration of SiO2 (〉70%), high alkali contents (Na20 + K20 = 7.14%-8.56%; K20〉N20; A/CNK = 0.99-1.20), and pronounced negative anomales in Eu, Ba, St, P and Ti. A SHRIMP zircon U-Pb age of 285±4 Ma was obtained for the Heiyingshan hornblende biotite granite intrusion. The geochemical and age dating data reported in this paper indicate that these granites were formed during the post-collisional crustal extension of the Southwest Tianshan orogenic belt, in agreement with the published data for the granites in the South Tianshan. 展开更多
关键词 Xinjiang Southwest Tianshan granite GEOCHEMISTRY SHRIMP zircon u-pb age
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New U-Pb age constraints on the upper Banxi Group and synchrony of the Sturtian glaciation in South China 被引量:19
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作者 Gaoyuan Song Xinqiang Wang +1 位作者 Xiaoying Shi Ganqing Jiang 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第5期1161-1173,共13页
The Nanhua basin in South China hosts well-preserved middle-late Neoproterozoic sedimentary and volcanic rocks that are critical for studying the basin evolution, the breakup of the supercontinent Rodinia, the nature ... The Nanhua basin in South China hosts well-preserved middle-late Neoproterozoic sedimentary and volcanic rocks that are critical for studying the basin evolution, the breakup of the supercontinent Rodinia, the nature and dynamics of the "snowball" Earth and diversification of metazoans. Establishing a stratigraphic framework is crucial for better understanding the interactions between tectonic, paleoclimatic and biotic events recorded in the Nanhua basin, but existing stratigraphic correlations remain debated, particularly for pre-Ediacaran strata. Here we report new Laser Ablation Inductively Coupled Plasma Mass Spectrometry(LA-ICPMS) U-Pb zircon ages from the middle and topmost Wuqiangxi Formation(the upper stratigraphic unit of the Banxi Group) in Siduping, Hunan Province, South China. Two samples show similar age distribution, with two major peaks at ca. 820 Ma and 780 Ma and one minor peak at ca. 910 Ma, suggesting that the Wuqiangxi sandstone was mainly sourced from Neoproterozoic rocks. Two major age peaks correspond to two phases of magmatic events associated with the rifting of the Nanhua basin, and the minor peak at ca. 910 Ma may correspond to the Shuangxiwu volcanic arc magmatism, which represents pre-collision/amalgamation subduction on the southeastern margin of the Yangtze Block. The youngest zircon group from the topmost Wuqiangxi Formation has a weighted mean age of 714.6±5.2 Ma, which is likely close to the depositional age of the uppermost Banxi Group. This age, along with the ages reported from other sections, constrains that the Banxi Group was deposited between ca. 820 Ma and ca. 715 Ma. The age of 714.6±5.2 Ma from the top of the Wuqiangxi Formation is indistinguishable with the SIMS U-Pb age of 715.9± 2.8 Ma from the upper Gongdong Formation in the Sibao village section of northern Guangxi, South China. It is also, within uncertainties, overlapped with two TIMS U-Pb ages from pre-Sturtian strata in Oman and Canada. These ages indicate that the Jiangkou(Sturtian) glaciation in South China started at ca. 715 Ma instead of ca. 780 Ma and support a globally synchronous initiation of the Sturtian glaciation at ca. 715 Ma. 展开更多
关键词 Nanhua basin WUQIANGXI Formation Banxi Group u-pb ZIRCON ageS Sturtian GLACIATION South China
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U-Pb Age and Hf Isotope Study of Detrital Zircons from the Wanzi Supracrustals:Constraints on the Tectonic Setting and Evolution of the Fuping Complex,Trans-North China Orogen 被引量:12
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作者 Xiaoping XIA Min SUN +5 位作者 Guochun ZHAO WU Fuyuan XU Ping Jian ZHANG Yanhong HE ZHANG Jiheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期844-863,共20页
Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of v... Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of various high-grade and multiply deformed rocks, including gray gneiss, basic granulite, amphibolite, fine-grained gneiss and marble, metamorphosed to upper amphibolite or granulite facies. It can be divided into four rock units: the Fuping TTG gneisses, Longquanguan augen gneisses, Wanzi supracrustals, and Nanying granitic gneisses. U-Pb age and Hf isotope compositions of about 200 detrital zircons from the Wanzi supracrustals of the Fuping Complex have been analyzed. The data on metamorphic zircon rims give ages of 1.82-1.84 Ga, corresponding to the final amalgamation event of the NCC, whereas the data for igneous zircon cores yield two age populations at -2.10 and -2.51 Ga, with some inherited ages scattering between 2.5 and 2.9 Ga. These results suggest that the Wanzi supracrustals were derived from the Fuping TTG gneisses (-2.5 Ga) and the Nanying granitic gneisses (2.0-2.1 Ga) and deposited between 2.10 and 1.84 Ga. All zircons with -2.51 Ga age have positive initial εHf values from +1.4 to +10.9, suggesting an important crustal growth event at -2.5 Ga through the addition of juvenile materials from the mantle. The Hf isotope data for the detrital zircons further imply that the 2.8 Ga rocks are important components in the lower crust, which is consistent with a suggestion from Nd isotope data for the Eastern Block. The zircons of 2.10 Ga population have initial εHf values of-4.9 to +6.1, interpreted as mixing of crustal re-melt with minor juvenile material contribution at 2.1 Ga. These results are distinct from that for the Western Block, supporting that the Fuping Complex was emplaced in a tectonic active environment at the western margin of the Eastern Block. 展开更多
关键词 detrital zircons u-pb age and Hf isotope Fuping Complex North China Craton
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Cretaceous Volcanic Events in Southeastern Jilin Province,China:Evidence from Single Zircon U-Pb Ages 被引量:7
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作者 CHEN Yuejun SUN Chunlin SUN Yuewu SUN Wei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1194-1200,共7页
Mesozoic volcanic rocks in southeastern Jilin Province are an important component of the huge Mesozoic volcanic belt in the northeastern area. Study of the age of their formation is of great significance to recognize ... Mesozoic volcanic rocks in southeastern Jilin Province are an important component of the huge Mesozoic volcanic belt in the northeastern area. Study of the age of their formation is of great significance to recognize Mesozoic volcanic rule in northeastern China. Along with the research of rare Mesozoic biota and extensive Mesozoic mineralization in western Liaoning, a number of researchers have focused on Mesozoic volcanic events. The authors studied the ages of the Cretaceous volcanic rocks in southeastern Jilin Province using single Zircon U-Pb. The result shows that the Sankeyushu Formation volcanic rocks in the Tonghua area are 119.2 Ma in age, the Yingcheng Formation in the Jiutai area 113.4±3.1 Ma, the Jinjiatun Formation in Pinggang Town of Liaoyuan City and the Wufeng volcanic rocks in the Yanji area 103.2±4.7 Ma and 103.6±1 Ma, respectively. Combined with the data of recent publication on volcanic rocks ages; the Cretaceous volcanic events in southeastern Jilin Province can be tentatively subdivided into three eruption periods: 119 Ma, 113 Ma and 103 Ma. The result not only provides important chronology data for subdividing Mesozoic strata in southeastern Jilin Province, establishing Mesozoic volcanic event sequence, discussing geological tectonic background, and surveying the relation between noble metals to the Cretaceous volcanic rocks, but also offers important information of Mesozoic volcanism in northeastern China. 展开更多
关键词 age of zircon u-pb volcanic event CRETACEOUS Jilin Province
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Zircon U-Pb Ages and Geochemistry of Permo-Carboniferous Mafic Intrusions in the Xilinhot Area, Inner Mongolia: Constraints on the Northward Subduction of the Paleo-Asian Ocean 被引量:5
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作者 WANG Ke LI Yilong +2 位作者 XIAO Wenjiao ZHENG Jianping Fraukje MBROUWER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第5期1261-1280,共20页
The Central Asian Orogenic Belt(CAOB) resulted from accretion during the Paleozoic subduction of the PaleoAsian Ocean. The Xilinhot area in Inner Mongolia is located in the northern subduction zone of the central-east... The Central Asian Orogenic Belt(CAOB) resulted from accretion during the Paleozoic subduction of the PaleoAsian Ocean. The Xilinhot area in Inner Mongolia is located in the northern subduction zone of the central-eastern CAOB and outcropped a large number of late Paleozoic mafic intrusions. The characteristics of magma source and tectonic setting of the mafic intrusions and their response to the closure process of the Paleo-Asian Ocean are still controversial. This study presents LA-ICPMS zircon U-Pb ages and geochemical features of mafic intrusions in the Xilinhot area to constrain the northward subduction of the Paleo-Asian Ocean. The mafic intrusions consist of gabbro, hornblende gabbro, and diabase. Their intrusion times can be divided into three stages of 326-321 Ma, 276 Ma and 254 Ma by zircon U-Pb ages. The first two stages of the 326-276 Ma intrusions mostly originated from subduction-modified continental lithospheric mantle sources that underwent a variable degree partial melting(5-30%), recording the subduction of oceanic crust. The third stage of the 254 Ma mafic rocks also show arc-related features. The primary magma compositions calculated by PRIMELT2 modeling on three samples of ~326 Ma and two samples of ~254 Ma show that these mafic samples are characterized by a variable range in SiO2(47.51-51.47 wt%), Al2O3(11.46-15.55 wt%), ΣFeO(8.27-9.61 wt%), MgO(13.01-15.18 wt%) and CaO(9.13-11.67 wt%), consisting with the features between enriched mantle and lower continental crust. The source mantle melting of mafic intrusions occurred under temperatures of 1302-1351°C and pressures of 0.92-1.30 GPa. The magmatic processes occurred near the crust-mantle boundary at about 33-45 km underground. Combined with previous studies, it is concluded that Carboniferous to early Permian(~326-275 Ma) northward subduction of the Paleo-Asian oceanic crust led to the formation of the mafic magmatism in the Baolidao arc zone. The whole region had entered the collision environment at ~254 Ma, but with subduction-related environments locally. The final collision between the North China craton and the South Mongolian microcontinent may have lasted until ca. 230 Ma. 展开更多
关键词 LA-ICPMS zircon u-pb age GEOCHEMISTRY MAFIC INTRUSIONS Paleo-Asian Ocean Central ASIAN Orogenic Belt
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New Insights into the Late Triassic Nadigangri Formation of Northern Qiangtang, Tibet, China: Constraints from U-Pb Ages and Hf Isotopes of Detrital and Magmatic Zircons 被引量:5
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作者 LI Xueren WANG Jian +2 位作者 CHENG Leli FU Xiugen WANG Yuke 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第4期1451-1467,共17页
We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depressio... We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depression, Tibet. Coupled with previously published data in the region, this paper proposes new insights into the geochronological framework for the Nadigangri Formation. The deposition ages of tuffite from top to bottom in the Woruo Mountain, Quem Co and Dongqu River, are 203 Ma, 226 Ma, 221.5 Ma and 221.1 Ma, respectively. The detrital zircons yield a younger cluster of ages of 201.5-225 Ma from the conglomerate of the Quem Co Formation. The Late Triassic Nadigangri Formation defines a temporal range approximately between 201 and 225 Ma (Norian-Rhaetian), including three predominant groups of 220-225 Ma, 210-217 Ma and 201-205 Ma, which correspond with the three main rifting episodes of initial rifting, further rifting and final rifting. Positive ~Hf(t) value and low model ages in younger detrital zircons suggests a juvenile character. However, the Hf isotopes of magmatic zircons display the presence of reworked ancient crust with 1.1-1.8 Ga. These results provide strong constraints not only on the temporal range of the Late Triassic Nadigangri Formation, but also on the onset of the Qiangtang Mesozoic rift basin. 展开更多
关键词 u-pb ages Hf isotope Nadigangri Formation Late Triassic QIANGTANG
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Zircon U-Pb Age and Geochemistry of the Ore-hosting Ultramafic Complex of Zhou'an PGE-Cu-Ni Deposit,Henan Province,Central China 被引量:6
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作者 YAN Haiqing DING Ruiying +5 位作者 TANG Zhongli WANG Yalei LIU Shuang MA Jiahong HU Yanqiang CHEN Kena 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1479-1487,共9页
The Zhou'an PGE-Cu-Ni deposit was recently discovered in the Qinling orogenic belt bound by the Yangtze and the North China Cratons. It is a blind deposit thoroughly covered by the Cenozoic alluvial sediments in the ... The Zhou'an PGE-Cu-Ni deposit was recently discovered in the Qinling orogenic belt bound by the Yangtze and the North China Cratons. It is a blind deposit thoroughly covered by the Cenozoic alluvial sediments in the Nanyang Basin. As the first large PGE-Cu-Ni deposit discovered in the Qinling-Dabie-Sulu orogenic belt, its geological and geochemical characteristic, isotope age, genesis and tectonic setting are of wide concern in both scientific studies and ore exploration. In this contribution, we report the results obtained from a pioneering study. The Zhou'an ultramafic complex is ferruginous, with m/f = 4.79-5.08, and shows the nature of tholeiite series. It is rich in light rare earth elements, Rb, Th, U, La, Sm, Zr and Hf, and poor in heavy rare earth elements, Nd and Ta, suggesting an intraplate setting. It has high S7Sr/S6Sr and low 143Nd/144Nd ratios. The ratios of Zr/Nb, La/Nb, Ba/ Nb, Rb/Nb, Th/Nb, Th/La and Ba/La, suggest the magma originated from lithosphere mantle. The Fo values of olivine and Pd/Ir-Ni/Cu diagram suggest primary magma was High Mg basalt. The laser ablation inductively coupled plasma atomic emission spectroscopy zircon U-Pb age is 641.5 ± 3.7 Ma. 展开更多
关键词 zircon u-pb age GEOCHEMISTRY ultramafic body PGE-Cu-Ni deposit tectonic setting
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Zircon LA-ICP-MS U-Pb Age and Island-Arc Origin of the Bayanhua Gabbro in the Hegenshan Suture Zone, Inner Mongolia 被引量:11
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作者 WANG Jinfang LI Yingjie LI Hongyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2316-2317,共2页
Objective The Bayanhua Nb-enriched gabbro is newly discovered in the Diyanmiao-Meilaotewula SSZ-type ophiolitic m61ange belt of the Hegenshan suture zone, Inner Mongolia. Nb-enriched arc gabbros are usually believed ... Objective The Bayanhua Nb-enriched gabbro is newly discovered in the Diyanmiao-Meilaotewula SSZ-type ophiolitic m61ange belt of the Hegenshan suture zone, Inner Mongolia. Nb-enriched arc gabbros are usually believed to result from partial melting of the mantle wedge peridotites metasomatized by slab melts derived from the subducting oceanic slab, which represent arc magmatic markers of the oceanic subduction zone. However, whether the Hegenshan ocean basin of the Paleo-Asian Ocean was in its subduction stage in the Early Permian requires further study for a final conclusion, and what is the evolution process of the oceanic subduction and lithospheric mantle of the Hegenshan suture zone remains speculative for the lack of further definitely petrological and chronological evidence and constraints. Therefore, this study carried out zircon LA-ICP-MS U-Pb geochronology and geochemistry on the Bayanhua Nb-enriched gabbro to discuss its origin, in order to provide new evidence for the tectonic evolution of the Hegenshan suture zone of the eastern Central Asian Orogenic Belt. 展开更多
关键词 Zircon LA-ICP-MS u-pb age and Island-Arc Origin of the Bayanhua Gabbro Inner Mongolia
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Zircon U-Pb age,trace element and Hf isotope composition of Sepon Au-Cu deposit, Laos:tectonic and metallogenic implications 被引量:6
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作者 Xin-yu Wang Dian-hua Cao +2 位作者 Zong-qi Wang An-jian Wang Yu-dong Wu 《China Geology》 2018年第1期36-48,共13页
The Truong Son Fold Belt,located at the northeastern margin of the Indochina Block,is considered to be tectonically linked to the subduction of the Paleotethys Ocean and subsequent collision.Sepon is one of the most i... The Truong Son Fold Belt,located at the northeastern margin of the Indochina Block,is considered to be tectonically linked to the subduction of the Paleotethys Ocean and subsequent collision.Sepon is one of the most important super large deposits of the Truong Son Fold Belt.Our LA-ICP-MS zircon U-Pb dating results show that granodiorite porphyry samples from the Sepon deposit have ages of 302.1-4-2.9 Ma, which is a crucial phase for magmatic-tectonical activities from the Late Carboniferous to Early Permian and has avital influence on the mineralization of copper and gold.Zircon from granodiorite porphyry yields εHf (t)values of 4.32 to 9.64,and TDM2 has an average age of 914 Ma,suggesting that the source of the granodiorite porphyry in the region were mainly mantle components but underwent mixing and contamination of crust materials.The Ce^4+/Ce^3+ value of zircon in the granodiorite porphyry varys greatly from 2.4 to 1438.29,which shows magma mixing might occur.Considering the characteristics of trace elements in the zircon and the whole rock geochemical characteristics of intrusion rocks as well as the characteristics of regional volcanic-sedimentary association,it is indicated that the tectonic setting may be the continental arc environment.The Sepon Au-Cu deposit is derived from emplacement of calc-alkaline intermediate-acid magma with coming from deep sources in the subduction process of the Paleotethys Ocean,forming porphyry Mo-Cu,skam Cu-Au mineralization and a hydrothermal sedimentary-hosted Au mineralization in the wall rocks. 展开更多
关键词 Granodiorite PORPHYRY ZIRCON u-pb ages Hf isotope Trace elements Sepon Laos
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LA-ICPMS U-Pb Ages of Zircon from Metaleucosomes, Olongbuluke Microcontinent, North Qaidam, and Implications on the Response to the Global Rodinia Supercontinent Assembly Event in NW China 被引量:3
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作者 王树庆 李晓彦 +3 位作者 陈能松 王新宇 王勤燕 柳小明 《Journal of China University of Geosciences》 SCIE CSCD 2006年第3期238-245,共8页
U-Pb dating was conducted on different domains of zircons from metamorphosed leucosomes in Delingha ( 德令哈) complex, the lower basement rocks of the Olongbuluke (欧龙布鲁克 ) microcontinent, North Qaidam, in or... U-Pb dating was conducted on different domains of zircons from metamorphosed leucosomes in Delingha ( 德令哈) complex, the lower basement rocks of the Olongbuluke (欧龙布鲁克 ) microcontinent, North Qaidam, in order to review its complex tectonothermal history. The zircon core is comprised of highly-modified magmatic zircon relicts, the zircon mantle was produced in response to anatexis of a Late Protoproterozoic thermal event; age and isotopic composition of both the zircon core and the zircon mantle have been seriously disturbed due to the thermal event related with growth of the zircon overgrowth rim. The 207 PIV 206 Pb apparent age of the overgrowth rim was estimated to be - 1 030 Ma. This Late Mesoproterozoic thermal event has been interpreted as a response to the global Rodinia supercontinent assembly event in the Olongbuluke microcontinent, Northwest China. 展开更多
关键词 zircon overgrowth u-pb age metamorphosed leucosome Rodinia supercontinent assembly northwest Qaidam.
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New detrital zircon U-Pb ages from BIF-related metasediments in the Ntem Complex (Congo craton) of southern Cameroon, West Africa 被引量:5
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作者 Nelson N. Chombong Emmanuel C. Suh Charles D. C. Ilouga 《Natural Science》 2013年第7期835-847,共13页
Banded Iron Formations (BIFs) were formed by contemporaneous events of active sediments supply and the venting of a hydrothermal fluid source at the Mid-Ocean-Ridge. BIFs within the Ntem Complex at the northern edge o... Banded Iron Formations (BIFs) were formed by contemporaneous events of active sediments supply and the venting of a hydrothermal fluid source at the Mid-Ocean-Ridge. BIFs within the Ntem Complex at the northern edge of the Congo Craton are intercalated with metasandstones and siltstones. SHRIMP U-Pb analysis on detrital zircons obtained from these metasediments gave variable ages from over 3000 Ma to 1000 Ma with the maximum age of deposition clustered around 1200 Ma and the peak of deposition at 1800 Ma. This age range suggested that the sub-basin was opened sometime in the Archean and remained active up till the Neoproterozoic. Zircons with Archean ages have a provenance linked to the charnockitic suite and the high-K granites within the Ntem Complex. The Paleoproterozoic ages are attributed to clastic inputs from the neigbouring Nyong Series west of the Ntem Complex. Also the peak of deposition in the Proterozoic could probably be explained by the globally recognized intense crust-forming processes in the Early Proterozoic time. The provenance of the younger Neoproterozoic ages is tied to various lithologies within the northern mobile belts of the Adamawa-Yade massifs and correlates with Neoproterozoic sedimentation ages in the Yaoundé, Lom and Poli series. The Neoproterozoic ages obtained are comparable to those obtained from metasediments of the Amazonian Craton and provide evidence of Pre-Gondwana assemblage of the Congo and the S?o Francisco Cratons. 展开更多
关键词 BIFs METASEDIMENTS Ntem COMPLEX SHRIMP u-pb age DETRITAL ZIRCONS
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New Zircon U-Pb Age of the Super-Large Lijiagou Spodumene Deposit in Songpan Garze Fold Belt, Eastern Tibet: Implications for Early Jurassic Rare-Metal Polymetallic Event 被引量:5
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作者 FEI Guangchun TIAN Jingjing +4 位作者 YANG Jiyi GAO Jianguo TANG Wenchun LI Jian GU Chenghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第3期1274-1275,共2页
Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the S... Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the SGFB,including the Xuebaoding,Jiajika,Keeryin rare metal deposits and Danba muscovite deposit(Li Jiankang et al.,2015).The newly discovered super-large Lijiagou 展开更多
关键词 New Zircon u-pb age of the Super-Large Lijiagou Jurassic Rare-Metal Polymetallic Event
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New Zircon U-Pb Age of the Babu Ophiolites in Southeast Yunnan,China and Constrains of Plate Subduction Time 被引量:4
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作者 HUANG Hu DU Yuansheng +1 位作者 YANG Jianghai YU Wenchao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1151-1152,共2页
Objective The Babu ophiolite in Malipo County of southeastern Yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China. It consists mainly of mafic and ultra... Objective The Babu ophiolite in Malipo County of southeastern Yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China. It consists mainly of mafic and ultramafic rocks. These rocks are very important to understand the evolution of the Paleo-Tethyan Ocean. However, the Babu ophiolite is still disputed and the mafic and ultramafic rocks have been inferred to be part of the Emeishan large igneous province (LIP) by some researchers. In this paper, we present zircon U-Pb data on the metabasalts in Malipo to reveal the formation time of mafic and ultramafic rocks and their tectonic nature. 展开更多
关键词 PB ICP MS Th is New Zircon u-pb age of the Babu Ophiolites in Southeast Yunnan China and Constrains of Plate Subduction Time of in
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Zircon U-Pb Ages of Bottom and Top Parts of the Zhangjiakou Formation in Lingyuan Area(West Liaoning Province) and Luanping Area (North Hebei Province) and Their Significance 被引量:3
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作者 ZhangHong LiuXiaoming +3 位作者 ZhangYeqing YuanHonglin HuZhaochu DiwuChunrong 《Journal of China University of Geosciences》 SCIE CSCD 2005年第2期115-129,共15页
In Lingyuan region of West Liaoning Province, the Zhangjiakou Formation (J_3z) and the Yixian Formation (K_1y) display an angular unconformity. That is, the Lower Mesozoic strata of the Zhangjiakou Formation are ENE (... In Lingyuan region of West Liaoning Province, the Zhangjiakou Formation (J_3z) and the Yixian Formation (K_1y) display an angular unconformity. That is, the Lower Mesozoic strata of the Zhangjiakou Formation are ENE (near E-W) oriented, while the overlying strata of the Yixian Formation exhibit an NNE orientation. The results of LA-ICP-MS zircon U-Pb ages show the Zhangjiakou Formation formed from about 130 Ma to 132 Ma in Lingyuan and 135 Ma to 136 Ma in Luanping (North Hebei Province), respectively. Three conclusions can be drawn: (1) The Zhangjiakou Formation in Lingyuan is comparable to that in Luanping, with the volcanic rocks of the Zhangjiakou Formation from Lingyuan being younger than those from Luanping. (2) 5-6 Ma difference between the top of the Zhangjiakou Formation and the bottom of the Yixian Formation in Lingyuan proves the angular unconformity between the two formations; and it reflects that the 5-6 Ma interval period is the main period of the transition of tectonic framework in Mesozoic in North Hebei and West Liaoning. In the interval period, the magmatic action went up to high tide in Mesozoic in the northeast of China. Moreover, after the interval period, the “Rehe fauna” developed into “erupted” period. This reflects that the interval period is also an important biological interface in Northern Hebei and Western Liaoning. (3) The Dabeigou Formation in Luanping should correspond to the upper part of the Zhangjiakou Formation, but not to the lower part of the Yixian Formation. 展开更多
关键词 zircon u-pb age Zhangjiakou Formation bottom and top bed Luanping and Lingyuan regions
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Zircon U-Pb Ages of the Chagangnuer Mafic Intrusion in Central Inner Mongolia and their Tectonic Implications 被引量:1
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作者 ZHANG Xiangxin GAO Yongfeng LEI Shihe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期771-773,共3页
The Central Asian Orogenic Belt(CAOB)is regarded as the world's largest and long-lived Phanerozoic accretionary orogen,which has recorded a long history of multiple subduction-accretion events during the Neoproter... The Central Asian Orogenic Belt(CAOB)is regarded as the world's largest and long-lived Phanerozoic accretionary orogen,which has recorded a long history of multiple subduction-accretion events during the Neoproterozoic to Mesozoic.The CAOB was formed by the progressive subduction of the Paleo-Asian Ocean(PAO).However,the final closure time of the PAO is still controversial,ranging from the Late Devonian to the Early-Middle Triassic(Zhang et al.,2018). 展开更多
关键词 ZIRCON u-pb ages TECTONIC Implications
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Zircon SIMS U-Pb Age of the Shaxinan Melagabbro, Eastern Tianshan and Constraints on Fe-Ti-V Oxide Mineralization 被引量:2
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作者 SHI Yu WANG Yuwang +6 位作者 WANG Jingbin MAO Qigui XIE Hongjing ZHOU Guochao ZHU Jiangjian WEI Xiaofeng Lü Xiaoqiang 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2039-2040,共2页
Objective The late Paleozoic Fe-Ti-V oxide deposit of the eastern Tianshan is an important orthomagmatic deposit type in the Central Asia Orogenic Belt (CAOB). A series of Fe-Ti -V oxide deposits and mineralized ma... Objective The late Paleozoic Fe-Ti-V oxide deposit of the eastern Tianshan is an important orthomagmatic deposit type in the Central Asia Orogenic Belt (CAOB). A series of Fe-Ti -V oxide deposits and mineralized mafic-ultramafic intrusions have been recognized recently, such as those in Hongliangzi, Weiya, Yaxi, Shaxinan and Shaxi on the Central Tianshan massif, and Niumaoquan on the southern margin of the Harlik belt (Shi et al., 2018a). Only a few Fe -Ti-V oxide deposits in the eastern Tianshan (e.g., Weiya and Niumaoquan) have been studied, and their chronology need to be further constrained for study of regional Fe-Ti- V oxide metallogenic mechanism and variation of mantlederived magmas during the orogenic process. 展开更多
关键词 Pb Zircon SIMS u-pb age of the Shaxinan Melagabbro FE Ti
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Geochemistry and zircon U-Pb ages of the Oligocene sediments in the Baiyun Sag, Zhujiang River Mouth Basin 被引量:2
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作者 Rui Sun Ming Ma +5 位作者 Kai Zhong Xiayang Wang Zhao Zhao Shuai Guo Xingzong Yao Gongcheng Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第2期123-135,共13页
In this study,element geochemistry and zircon chronology are used to analyze the Oligocene sediments in the Baiyun Sag,Zhujiang River Mouth Basin.The experimental results are discussed with respect to weathering condi... In this study,element geochemistry and zircon chronology are used to analyze the Oligocene sediments in the Baiyun Sag,Zhujiang River Mouth Basin.The experimental results are discussed with respect to weathering conditions,parent rock lithologies,and provenances.The chemical index of alteration and the chemical index of weathering values of mudstone samples from the lower Oligocene Enping Formation indicate that clastic particles in the study area underwent moderate weathering.Mudstone samples exhibit relatively enriched light rare earth elements and depleted heavy rare earth elements,"V"-shaped negative Eu anomalies,and negligible Ce anomalies.The rare earth element distribution curves are obviously right-inclined,with shapes and contents similar to those of post-Archean Australian shale and upper continental crust,indicating that the samples originated from acid rocks in the upper crust.The Hf-La/Th and La/Sc-Co/Th diagrams show this same origin for the sediments in the study area.For the samples from the upper Enping deltas,the overall age spectrum shows four major age peaks ca.59–68 Ma,98–136 Ma,153–168 Ma and 239–260 Ma.For the Zhuhai Formation samples,the overall age spectrum shows three major age peaks ca.149 Ma,252 Ma and 380 Ma.The detrital zircon shapes and U-Pb ages reveal that during Oligocene sedimentation,the sediments on the northwestern margin of the Baiyun Sag were supplied jointly from two provenances:Precambrian-Paleozoic metamorphic rocks in the extrabasinal South China fold zone and Mesozoic volcanic rocks in the intrabasinal Panyu Low Uplift,and the former supply became stronger through time.Thus,the provenance of the Oligocene deltas experienced a transition from an early proximal intrabasinal source to a late distal extrabasinal source. 展开更多
关键词 weathering degree lithology of parent rock PROVENANCE element geochemistry zircon u-pb ages Baiyun Sag
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Discovery of the Dagele Eclogite in East Kunlun,Western China and Its Zircon SHRIMP U-Pb Ages:New Constrains on the Central Kunlun Suture Zone 被引量:6
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作者 DU Wei JIANG Changyi +5 位作者 Tang Zhongli XIA Mingzhe XIA Zhaode LING Jinlan ZHOU Wei WANG Bangyao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1153-1154,共2页
Objective Eclogites are important indicators of ancient plate boundaries or paleosuture zones. Despite their great geological significance, very few investigations have been carried out in the Kunlun region. The Centr... Objective Eclogites are important indicators of ancient plate boundaries or paleosuture zones. Despite their great geological significance, very few investigations have been carried out in the Kunlun region. The Central East Kunlun fault zone was believed to be an Early Paleozoic suture zone, but there has been no reliable evidence for this, though studies on ophiolite, granite, and basic granulite indicate that the Early Paleozoic orogeny occurred in the East Kunlun. This work focused on the Dagele eclogites in Central East Kunlun to provide new constraints for the Central East Kunlun suture zone. 展开更多
关键词 SHRIMP Pb Discovery of the Dagele Eclogite in East Kunlun Western China and Its Zircon SHRIMP u-pb ages:New Constrains on the Central Kunlun Suture Zone of in on
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