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Chinese Journal Of Geochemistry 1989年第1期8卷 65-71页

作者：朱炳泉王慧芬毛存孝朱乃娟黄荣生彭建华蒲志平 Institute of Geochemistry Academia Sinica Guiyang

The available petrochemical data indicate that volcanic rocks in the Sanshui basin of Guangdong Prov-ince are characteristic of the island-arc tholeiite-calc-alkaline *** K-Ar ages range from 43 to 64 Ma,corresponding to Early *** Nd-Sr-Pb isotopic correlations give two binary mixing trends,indicating a mixed source of Leiqiong depleted mantle,seawater and altered sediments pertaining to *** studies have confirmed the existence of an ancient subduction zone beneath the South Chi-na continent,which is considered to have resulted from the suturing of various terrains in southern China.

关键词：地球年代学钕同位素锶同位素铅同位素地壳古消亡带三水盆地广东

SHRIMP zircon U-Pb geochronology of Indosinian granites in Hunan Province and its petrogenetic implications

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Chinese Science Bulletin 2005年第13期50卷 1395-1403页

作者： WANGYuejun FANWeiming LIANGXinquan PENGTouping SHIYuruo KeyLaboratoryofIsotopeGeochronologyandGeochemistry GuangzhouInstituteofGeochemistryChineseAcademyofSciencesGuangzhou510640China SHRIMPIsotopeLaboratory ChineseAcademyofGeologicalSciences.Beijing100037China

The SHRIMP zircon U-Pb geochronology ofthree typically Indosinian granitic plutons with peralumi-nous and potassium-rich affinities (Tangshi ultraunit forWeishan and Baimashan, and Longtan ultraunit forGuandimiao) is presented in Hunan Province, South *** analyses of zircons from biotite monozonite granites forWeishan, Baimashan and Guandimiao plutons show the sin-gle and tight clusters on the concordia, and yield theweighted mean 206Pb/238U ages of 244±4, 243±3 and 239±3Ma, respectively, representing the crystallized ages of theseIndosinian granites. These data suggest that the Indosiniangranitic plutons as previously thought formed at a narrowage span. In combination with other data, it is inferred thatthe Indosinian granites within the South China Block proba-bly distributed in Hunan, Jiangxi, Guangxi and Guangdongprovinces as planar shape, and were the derivation of thecrustal materials in the intracontinental thickening *** precisely geochronological data provide importantconstraints for better understanding the spatiotemporal pat-tern of the Indosinian peraluminous granites and earlyMesozoic tectonic evolution of the South China Block.

关键词：锆石地球年代学花岗岩岩石学

Sm-Nd isotopic geochronologyof the Yinachang Fe-Cu-REE deposit at Wuding,Yunnan Province and its genetic significance

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Chinese Science Bulletin 2005年第18期50卷 2090-2096页

作者： YANG Yaomin TU Guanzhi HU Ruizhong SHI Xuefa Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China The Key Laboratory of Marine Sedimentology and Environmental Geology The First Institute of Oceanography SOA Qingdao 266061 China Northwest Geological Exploration Bureau CNNC Xi'an 710054 China

Sm-Nd isotope systematics of ores and fluorites places precise time constraints on REE mineralization of the Yinachang Fe-Cu-REE deposit in Yunnan Province which occur in the Proterozoic Kunyan group. The ore-related fluorites contain high abundant REE, and show a strong enrichment of LREE and a positive Eu anomaly, which is in marked contrast to post-ore fluorites that are HREE en-riched. The Sm-Nd isochron ages of the ores and fluorites are 1539±40 Ma and 1617±100 Ma, respectively, and calculated εNd(t) are ?4.6 and ?3.2. Accurate age determinations of the mineralization demonstrate that the REE mineralization took place during early Mesoproterozoic. Together with other geological evidence from the ore deposit, the primary REE-bearing ore-forming fluids are suggested to have been derived from the Enriched Mantle, and the Yinachang Fe-Cu-REE ore deposit is of volcanic exhalation- hydro-thermal sedimentary origin. This study also imply that the sudden large-scale REE mineralization in the Mesoprotero-zoic epoch may have been induced by alkaline-rich anoro-genic magmatism which occurred at marginal rifts of the continent in the Mesoproterozoic.

关键词：峡谷沉积物氟石同位素地球年代学

SHRIMP U-Pb zircon geochronology of granulites at Rimana(Southern Tibet)in the central segment of Himalayan Orogen

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Chinese Science Bulletin 2003年第23期48卷 2647-2650页

作者： LIDewei LIAOQunan YUANYanming WANYusheng LIUDemin ZHANGXionghua YIShunhua CAOShuzhao XlEDefan FacultyofEarthSciences ChinaUniversityofGeosciencesWuhan430074China InstituteofGeology ChineseAcademyofGeosciencesBeijing130073China

High-pressure mafic granulites, occurring as lenses within gneisses and quartzite in the central segment of the Himalayan orogen, were dated using SHRIMP U-Pb technique. 13 analyses out of a total of 15 are plotted along a concordia line and yield a mean 206Pb/238U age of 17.6 0.3 Ma. This age indicates adiabatic decompression and a metamorphic event associated with rapid uplift of granulites in a tectonic environment resulted from the collision between India and Eurasia, synchronous with large-scale thrusting, extension, detachment as well as emplacement of leu-cogranite. One analysis gives a 206Pb/238U age of 29.5 0.4 Ma that is interpreted to represent the timing of the final closure of the Neo-Tethys. Another age is 1991 26 Ma that represents the age of the protolith of the granulites. In sum-mary, dating results show that granulites in this area under-went multiphase metamorphism and complex geological evolution.

关键词：锆石地球年代学麻粒岩西藏喜玛拉雅山脉大陆运动

SHRIMP U-Pb geochronology of the detrital zircons from the Longshoushan Group and its tectonic significance

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Chinese Science Bulletin 2007年第10期52卷 1414-1425页

作者： KuoAn TUNG HoungYi YANG LIU DunYi ZHANG JianXin ChienYuan TSENG WAN YuSheng Department of Earth Sciences Cheng Kung University Tainan 701 China Museum of Natural Science Taichung 404 China Beijing SHRIMP Centre Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Sixty-two geologically meaningful U-Pb dates were obtained by using SHRIMP technique for the detrital zircons in three metasedimentary rocks from stratigraphically uppermost parts of the Longshoushan Group in the present study. Eighty percents of these dates range from 1.7 Ga to 2.2 Ga with a peak at 1.8-2.0 Ga and twenty percents from 2.3 Ga to 2.7 Ga. The youngest detrital zircon is dated at 1724±19 Ma which is interpreted as the maximum depositional age of the metasedimentary rocks. Therefore, the age for the diagenesis and lithification of the original sedimentary rocks of the Longshoushan Group before the metamorphism must be younger than 1724±19 Ma. Comparison of the age histograms of these detrital zircons with the ages of the igneous rocks on the surrounding older massifs suggests that the sediments of the Longshoushan Group were most likely derived from the Alaxa Block and Tarim Craton. This implies that the affinity between Alaxa Block and Tarim Craton was strong and that they might have been a unified craton during middle-early Proterozoic time.

关键词：甘肃龙首山组 SHRIMP U-Pb 地球年代学岩屑锆石变质沉积岩

SHRIMP U-Pb zircon geochronology and its implications on the Xilin Gol Complex,Inner Mongolia,China

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Chinese Science Bulletin 2003年第24期48卷 2742-2748页

作者： SHIGuanghai LIUDunyi ZHANGFuqin JIANPing MIAOLaicheng SHIYuruo TAOHua InstituteofGeologyandGeophysics ChineseAcademyofSciencesBeijing100029China SHRIMPLab InstituteofGeologyChineseAcademyofGeologicalSciencesBeijing100037China

The Xilin Gol Complex, consisting of deformed and metamorphosed rocks, was exposed as a large geological unit within the Central Asian Orogenic Belt, but its forming and subsequent deformed and metamorphic time has been an issue of little consensus. Petrographic analyses and SHRIMP dating on biotite-plagioclase gneiss, one of the ma-jor rocks within the Xilin Gol Complex, in southeast Xilinhot City, Inner Mongolia, China, where the Xilin Gol Complex was identified and named, yield its lower limit age of 437 3 Ma (2s ) by its magmatic zircon SHRIMP U-Pb dating, and an upper limit age of 316 3Ma (2s ), which was constrained by SHRIMP dating of magmatic zircons from adjacent un-deformed garnet-bearing granite which intruded the Com-plex. The Complex was thus determined to be formed and subsequently deformed/metamorphosed from the late Ordovi-cian-early Silurian to the mid-Carboniferous. Consequently, it is not the Precambrian terrane as previously considered by most geologists. More or less, the major rock——biotite- plagioclase gneiss within the Complex is more likely to be Paleozoic fore-arc turbidite formation before metamorphism and intensive deformation, in which the detrital zircons gave sporadic Precambrian ages as old as up to 3.1 Ga. The source of the turbidite formation is multiple, which may be derived either from the North China Craton, or from the South- Mongolia Micro-continent, or probably came from a poten-tial and undiscovered in situ terranes aged 600—800 Ma or even up to ca 3.1 Ga near the Complex.

关键词：锆石地球年代学内蒙古中国变质岩

SHRIMP U-Pb zircon geochronology of Yangfang aegiriteaugite syenite in Wuyi Mountains of South China and its tectonic implications

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Chinese Science Bulletin 2003年第20期48卷 2241-2247页

作者： WANGQiang ZHAOZhenhua JIANPing BAOZhiwei XlONGXiaolin MAJinlong GuangzhouInstituteofGeochemistry ChineseAcademyofSciencesGuanlzhou510640China GeologicalInstitutelChineseAcademyofGeologicalSciences Beijing100037.China

In addition to the wide spread peraluminous granites, some alkaline or alkali-rich intrusive rocks were recently observed in the Wuyi Mountains. The Yangfang aegiriteaugite syenites in the Wuyi Mountains are strongly enriched in light rare earth elements (LREE), K, Ba, Ga, Zr and Y. What is more, differentiations of REE are obvious. In addition, the Yangfang aegiriteaugite syenites have also some characteristics similar to A-type granite. Zircons are selected from the Yangfang aegiriteaugite syenites for Sensitive High-Resolution Ion Microprobe (SHRIMP-Ⅱ) U-Pb geochronology study. 15 analyses give concordant 206Pb/238U ages in a narrow range of 233—249 Ma, which correspond to a single age population with a weighted mean 206Pb/238U age of 242 4 Ma, which records the crystallization time of the aegiriteaugite syenites. It is suggested that: (1) there were early Triassic peralkaline intrusive rocks in South China; (2) the early Indosinian extension event was probably active in local area, South China. This discovery provides a new insight for farther understanding of 揑ndosinian orogeny in South China.

关键词：中国南部武夷山霓辉石正长岩锆石U-Pb测年地球年代学地质构造

SHRIMP U-Pb geochronology of the zircons from the Precambrian basement of the Qilian Block and its geological significances

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Chinese Science Bulletin 2007年第19期52卷 2687-2701页

作者： Kuoan TUNG Huai-Jen YANG Houng-Yi YANG LIU DunYi ZHANG JianXin WAN YuSheng Chien-Yuan TSENG Department of Earth Sciences Cheng-Kung University Tainan 701 China Museum of Natural Science Taichung 404 China Beijing SHRIMP Centre Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Origin and tectonic evolution of the Qilian Precambrian basement on NW China were investigated using zircon U-Pb ages with collaborating stratigraphic and paleontological evidence. Zircon grains were separated from two schists, two granitic gneisses and one mylonized gneiss and dated with SHRIMP. Seventy percent of sixty-one detrital zircon ages from two schists ranges from 0.88 Ga to 3.09 Ga, mostly within 1.0 Ga to 1.8 Ga with a peak at 1.6 Ga to 1.8 Ga, and twenty percent varies from 2.0 Ga to 2.5 Ga. A few falls in the Archean and Neoproterozoic periods. The two granitic gneisses were dated 930±8 Ma and 918±14 Ma, whereas the mylonized granitic gneiss was dated 790±12 Ma. These ages represent two periods of magmatisms, which can be correlated with the early and late stages of magmatisms associated with the Jinningian movement on the Yangtze Blocks. The results from this and previous studies indicate that the ages of the Precambrian detrital zircons from the Qilian Block are widely distributed in the Proterozoic era, distinct from the North China Block which was stable in the Neo-Mesoproterozoic era. By contrast, the age histograms of the detrital zircons from the Qilian Block is similar to those from Precambrian basement of the Yangtze Craton. Therefore, it is suggested that the Qilian Block had a strong affinity toward the Yangtze Craton and might belong to the supercontinent Gondwana in the Neoproterozoic time. This inference is supported by Nd model age (TDM), stratigraphic, and paleontological evidence. It is further considered that the Qilian Block was rifted from the supercontinent Gondwana during late Sinian to form an isolated continent in the Proto-Tethyan Ocean, moving towards the Alaxa Block in the North China Craton. The part of Proto-Tethyan Ocean between the Qilian and Alaxa Blocks should correspond to the so-called Paleo-Qilian Ocean. Following the closure of the Paleo-Qilian Ocean in the early Paleozoic, the Qilian Block collided with the Alaxa B

关键词：地球年代学锆石前寒武纪古地中海特提斯海

Rb-Sr Geochronology and Magma Source of the Mesozoic Fault-Granite Belt, East Shandong

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Chinese Journal Of Geochemistry 1993年第2期12卷 118-127页

作者：迟效国林景仟 Changchun University of Earth Science Changchun 130061

Developed in the southeast coast of te East Shandong Peninsula,the Mesozoic fault-magma belt consists of five rock series:the syenite series;the monzonite series;the megaporphyritic monzogranite series;the biotite-granite series;and the alkali granite *** on their Rb-Sr isochron ages(122-220Ma),these rock series may be divided into three magma subcycles dated at Triassic,Late Jurassic and Early *** initial ^87Sr/^86Sr ration in these rock series range from 0.70436 to *** starting points of the Rb-Sr isochrons exhibit four different distribution trends on the(^87Sr/^86Sr)i-^87Rb/^86Sr *** characteristics show that the multiple granitic rock series are different in genesis and *** syenite series might be derived from the combination of mantle-derived magma and crustal material,and the others could be derived from granulite-facies and amphibilite-facies rocks in the deep crust.

关键词：铷-锶地球年代学岩浆山东铷同位素花岗岩岩浆岩

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牡丹江地区黑龙江杂岩的变质变形特征

吉林大学学报（地球科学版） 2009年第6期39卷 1066-1072页

作者：王跃张兴洲宋海峰张春艳熊小松中国地质科学院地质研究所北京100037 吉林大学地球科学学院长春130061 长春工程学院勘查与测绘工程学院长春130021

黑龙江牡丹江地区出露一套具有洋壳性质的构造混杂岩,根据特征矿物组合及岩相学特点,将这套杂岩自北向南划分为3个变质变形相带：蓝片岩带、黑硬绿泥石带和黑云母带,带与带之间被强烈的韧性变形带所分隔,表明彼此间为构造接触,而非连续... 详细信息

黑龙江牡丹江地区出露一套具有洋壳性质的构造混杂岩,根据特征矿物组合及岩相学特点,将这套杂岩自北向南划分为3个变质变形相带：蓝片岩带、黑硬绿泥石带和黑云母带,带与带之间被强烈的韧性变形带所分隔,表明彼此间为构造接触,而非连续的变质相带,说明了牡丹江地区的黑龙江杂岩不是正常的变质地层单元。3个相带的出露与自北向南的逆冲推覆事件有关。根据黑龙江杂岩变质变形特征和其年代学资料,将本区构造演化划分为3个阶段：（1）305～296 Ma之前的陆间洋洋壳俯冲及闭合阶段;（2）170.26～154 Ma佳木斯和兴凯地块之间的陆陆碰撞和后期作为整体统一受西太平洋构造域影响的阶段;（3）154 Ma之后敦密断裂左行走滑并对黑龙江杂岩进行改造的阶段。

关键词：蓝片岩变质变形相带黑龙江杂岩佳木斯地块兴凯地块地球年代学