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Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, China

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate School of Guizhou University, Guiyang 550025, China Nanjing Institute of Geology and Mineral Resources, Nanjing 210016, China geological Survey of no. 3 geological party, Xinjiang, Kurle 841000, China) Postgraduate School of Guizhou University Guiyang 550025 China Nanjing Institute of Geology and Mineral Resources Nanjing 210016 China geological Survey of no. 3 geological party Xinjiang Kurle 841000 China

Large amounts of vermicular fossils and a mino. amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3-1. 4 mm wide; their wrinkled lamellae are microfine with 3-10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

Geochrono.ogy, Geochemistry and Sr-Nd-Pb-Hf Isotopes of no. I Complex from the Shitoukengde Ni–Cu Sulfide Deposit in the Eastern Kunlun Orogen, Western China: Implications for the Magmatic Source, Geodynamic Setting and Genesis

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 106-126页

作者： LI Liang SUN Fengyue LI Bile LI Shijin CHEN Guangjun WANG Wei YAN Jiaming ZHAO Tuofei DONG Jun ZHANG Dexin College of Earth Sciences Jilin University Changchun 130061 China Qinghai Bureau of geological Survey Xining 810001 China no. 108 geological party Sichuan Bureau of Geology and Mineral Exploration Chengdu 611230 China

The Shitoukengde Ni-Cu deposit, located in the Eastern Kunlun Orogen, comprises three mafic-ultramafic complexes, with the no. I complex hosting six Ni-Cu orebodies found recently. The deposit is hosted in the small ultramafic bodies intruding Proterozoic metamorphic rocks. Complexes at Shitoukengde contain all kinds of mafic-ultramafic rocks, and olivine websterite and pyroxene peridotite are the most important Ni-Cu-hosted rocks. Zircon U-Pb dating suggests that the Shitoukengde Ni-Cu deposit formed in late Silurian （426-422 Ma）, and their zircons have ~Hf（t） values of-9.4 to 5.9 with the older TDMm ages （0.80-1.42 Ga）. Mafic-ultramafic rocks from the no. I complex show the similar rare earth and trace element patterns, which are enriched in light rare earth elements and large ion iithophile elements （e.g., K, Rb, Th） and depleted in heavy rare earth elements and high field strength elements （e.g., Ta, Nb, Zr, Ti）. Sulfides from the deposit have the slightly higher ~34S values of 1.9-4.3%o than the mantle （0 ~ 2%o）. The major and trace element characteristics, and Sr-Nd-Pb and Hf, S isotopes indicate that their parental magmas originated from a metasomatised, astheno.pheric mantle source which had previously been modified by subduction-related fluids, and experienced significant crustal contamination both in the magma chamber and during ascent triggering S oversaturation by addition of S and Si, that resulted in the deposition and enrichment of sulfides. Combined with the tectonic evolution, we suggest that the Shitoukengde Ni-Cu deposit formed in the post-collisional, extensional regime related to the subducted oceanic slab break-off after the Wanbaogou oceanic basalt plateau collaged no.thward to the Qaidam Block in late Silurian.

关键词： Sr-Nd-Pb-Hf isotopes crustal contamination oceanic slab break-off post-collisionalextension Shitoukengde Ni-Cu deposit Eastern Kunlun Orogen

Strontium isotope geochemistry of the Lemachang independent silver ore deposit, no.theastern Yunnan, China

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Science China Earth Sciences 2000年第4期43卷 337-346页

作者：邓海琳李朝阳涂光炽周云满王崇武 The Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China no. 1 geological party of the Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China

Sr isotope geochemical studies (the87Sr/86Sr and δ18O-87Sr/86Sr systems) on the wall rocks and ores from the Lemachang independent Ag deposit in no.theastern Yunnan provide strong evidence that the ore-forming fluids had flown through radiogenetically Sr-enriched rocks or strata prior to their entry into the locus of ore precipitation, and water-rock interaction is the main mechanism of Ag ore precipitation. The radiogenetically Sr-enriched source region may be the Proterozoic basement (the Kunyang and Hekou groups). Moreover, the theoretical modeling of the Sr isotopic system indicates that the ore-forming fluids contain as much as 3×10-6 Sr with isotopic composition of Sr being 0.750 and that of oxygen 7.0‰ The ore-forming temperatures were estimated at 150–250°C for the carbonate rock-type ores and at 200–260°C for the clastic rock-type.

关键词： Lemachang no.theastern Yunnan independent Ag deposit Sr isotope ore-forming fluid.

The Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County, Yunnan Province

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 271-287页

作者： Zhao Daxian Tang Guangting The Fifth geological party, Yunnan Bureau of Geology and Mineral Resources, Simao,Yunnan Liu Linqun The Fifth geological party Yunnan Bureau of Geology and Mineral Resources Sirnao Yunnan

Through studies on the element geochemistry, alteration of country rocks, ore-forming fluids and isotopegeochemistry of the Arno.tin deposit in the metamorphic rocks of the Upper Proterozoic Ximeng Group, theauthors consider that the concentration of the B-F-Li-Rb-Cs-Sn association is related to acidic magmatism inthe study area. The Fe-Mg-Li tourmaline in the ore is the replaced product of the country rocks byhypothermal fluid. The δ^(18)O values of mineral separates are +2.01- +13.16‰ and their δ^(34)S values, +2.6-+7.2‰. The ore-forming materials were derived from hydrothermal fluid of granitic magma. For themineralization, the temperature is 450°-350℃, the pressure, 450-1000×10~5 Pa, and the age, Himalayan(21.5 Ma). According to the geochemical characteristics, a minerogenic model is established: the deposit is ahypothermal cassiterite-quartz vein type tin deposit controlled by the hidden Himalayan granites.

关键词： The Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County Yunnan Province

Metamorphic Rock-hosted Disseminated Gold Deposits——A Case Study of the Xiaotongjiapuzi Gold Depositof Eastern Liaoning

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Acta Geologica Sinica(English Edition) 1999年第4期73卷 429-437页

作者： LIU Guoping AI Yongfu FENG Kezhu ZHANG Zhimin Beijing Institute of Geology for Mineral Resources CNNC Beijing 100012 Department of Geology Peking University Beijing 100871 no. 103 geological party Liaoning Bureau of Geological Exploration CNNC Dandong Liaoning 118008

The Xiaotongjiapuzi gold deposit occurs in a Palaeoproterozoic rift accretionary terrane in eastern Liaoning and is hosted by a carbonate formation of the Dashiqiao Formation, Liaohe Group. The metamorphic grade of the host rock is low amphibolite-high greenschist facies. Gold, which is mainly invisible, is distributed in pyrite and arseno.yrite. The grains of Au-bearing sulphide minerals are fine, ranging from 0.0 n to 1 mm. The wall-rock alterations are characterized by low-temperature silification, hydro-sericitization, sericitization and carbonatization. The homogenization temperatures of the fluid inclusions in quartz closely associated with gold mineralization range from 140 to 240°C. The metallogenic age represented by the Ar-Ar isotopic age of sericite is 167 Ma. Comparisons and studies show that the Xiaotongjiapuzi gold deposit can be classified as the submicron-sized disseminated deposit (analogous to the Carlin-type) hosted in metamorphic rocks.

关键词： disseminated gold deposit eastern Liaoning metamorphic rock

Discovery and significance of Xucun late Proterozoic composite dike swarm in southern Anhui Province

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Chinese Science Bulletin 1997年第4期42卷 328-330页

作者： Tang, HF Zhou, XM Zhi, LG Department of Earth Sciences Nanjing University Nanjing China no. 332 geological party Bureau of Geology and Mineral Resources of Anhui Province Huangshan China

geologicalLY, southern Anhui Province, East China, is a part of late Proterozoic collision orogens of the southeast margin of the Yangtze Block. In this region the development of late Proterozoic Fuchuan ophiolite suite and collision granitoids of Xiuning, Xucun and Shexian mark the existence of the intensely tectonic-magmatic events. Recently discovered Xucun

关键词： late Proterozoic composite dike swarm southern Anhui Province.

On the Genesis of Uranium Deposit 720 with Special Reference to the Double Solution-Mixing Model

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Chinese Journal Of Geochemistry 1991年第1期10卷 1-10页

作者：李振球胡中林 geological party 301 Bureau of Geological ExplorationSouth-Central China

Presented in this paper is an approach to the analysis of 'series-stage'*** processes of hydrothermal evolution involved in ore deposition,the factors affecting the enrichment of uranium and the source of ore forming elements in uranium deposit 720 are also discussed .In addition,the ore-forming tem-perature and pressure as well as the pH,Eh and chemical composition of ore-forming medium are studied with reference to the fluid inclusion data available.A double solution-mixing model has been proposed to explain the genesis of the uranium deposit studied.

关键词：铀矿床成因 PH值成矿物质流体包裹体成矿作用

Zircon U-Pb Age of the Shangxu Gold Deposit from Bangong-Nujiang Co, no.thern Tibet, and Restriction on the Early Cretaceous Orogenic Gold Mineralisation

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1664-1666页

作者： HUANG Hanxiao LI Guangming LIU Hong CAO Huawen ZHANG Zhilin Chengdu Center China Geological Survey Chengdu 610081 China no.5 geological party of Tibet geological Exploration Bureau Golmud 816000 Qinghai China

Objective The Tibetan Plateau is the largest continent-to-continent collision belt in the world. Two orogenic gold mineralisation belts have been recognized in this collision belt, which are as follows： the Indus-Yarlung Zangbo suture zone orogenic gold belt （IYOG）, represented by the Mayoumu and Bangbu gold deposits, and the Ailaoshan orogenic gold belt （AOG）, whose typical cases include the Zhenyuan and Chang＇an gold deposits. The IYOG formed during 54-45 Ma corresponds to the compressional deformation during the early stages of the collision of the plates of India and Eurasia, whereas the AOG formed in 38-29 Ma corresponds to that during the later stage of the collision. Recently, several medium- to large-sized gold deposits （e.g., the Dacha and Shangxu deposits） have been discovered along the Bangong Co-Nujiang suture belt, which indicates that ano.her orogenic gold mineralisation belt existed within the Tibetan Plateau. However, the lack of a mineral suitable for dating or for altering the minerals that were affected by various tectonic thermal events causes difficulty to perform accurate dating. This study is based on the Shangxu gold deposit and analyses the genesis of zircon in gold-bearing quartz veins as well as the accurate gold-forming age by hydrothermal zircon micro probe analysis using the U-Pb （LA-ICP-MS） method.

关键词： ICP MS Pb

First Report of Zircon U-Pb Chrono.ogy and Hf Isotope Evidence of the Heluositan Group Granulite in West Kunlun, Xinjiang

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 868-869页

作者： GUO Xincheng CHEN Bangxue ZHOU Nengwu GAO Jun ZHENG Yuzhuang no.11 of geological party Xinjiang Bureau of Geology and Mineral Exploration and Development

Objective As the uplift belt on the southem margin of the Tarim block, the Tiekelike block consists mainly of a set of Precambrian metamorphic rocks with granulite and gneisses. The Heluositan group-complex is the most ancient rock series in the area, and is a key area for studying the formation and evolution of the Precambrian basement of the Tarim craton. LA-ICP-MS zircon U-Pb dating and Hf isotopic analysis of granulite in this area provide new evidence for revealing the formation and evolution of the Precambrian basement in the Tarim Basin.

关键词： Hf MS Pb Xinjiang First Report of Zircon U-Pb Chrono.ogy and Hf Isotope Evidence of the Heluositan Group Granulite in West Kunlun