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| 1 | The Late Mesozoic Orogenic Processes of Mongolia-Okhotsk Orogen: Evidence from Field Investigations into Deformation of the Mohe Area, NE China显示文摘Based on field investigation in 1999, two deformational domains with d ifferent dynamics have been distinguished from the Jurassic geological outcrops in the Mohe area of NE China, i.e. northern ductile and southern plastic-brittl e ones. Their deformational features are stated in this paper. And then, three st ages of structural deformation of the area relative to the late Mesozoic orogeni c processes of Mongolian-Okhotsk orogen are reconstructed as follows, (1) south w ards thrusting in the middle-late Jurassic, (2) eastwards thrusting and strike -s lipping parallel to the orogen in the late Jurassic, and (3) southeastwards thru sting in the early Cretaceous. | Li Jinyi, He Zhengjun, Mo Shenguo and (Institute of Geology, CAGS, Beijing 100037, China) Zheng Qingdao (Heilongjiang Bureau of Exploration and Exploitation of Geology and M ineral Resources, Ha’erbin 150036, China) | 1999 | Global Geology1999，4，2： | 26 |
| 2 | The Y.D.and climate abrupt events in the early and middle Holocene:Stalagmite oxygen isotope record from Maolan,Guizhou,China显示文摘The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 45 cm to 193.6 cm of the upper part of D4 stalagmite from Dongguo Cave in Libo, Guizhou, by using system TIMS U-series dating and carbon and oxygen stable isotope analyses.The study indicates that the last cold event, the YD (Younger Dryas) event, of the last glacial period was apparently shown in D4 record, which started from 12.80 kaBP and ended in 11.58 kaBP, with a great range of drop in temperature. The end of the last glacial period was consistent with the termination I in oceanic isotope records and was with time limit of 11.3 kaBP. The three most distinct cold events in the early and middle Holocene occurred respectively in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop in tem- perature reaching 2—5℃. The climate abrupt events in thousand and hundred years scale re- corded in stalagmite δ O can be compared to those in GISP2 ice cores from Greenland in their 18 happening time and the range of their lasting time. The cold events in 8.27 kaBP and 4.75 kaBP can also be compared to CC3 stalagmite records in Ireland, which indicate that climate changes of short range in China monsoon areas, western Europe and polar regions, have the same driv- ing factor. This has a global significance. In addition, the trend of record curves in some time- stages is apparently different, which reflects probably the difference between environment in monsoon climate areas and in polar regions. | QIN Jiaming1, YUAN Daoxian1, CHENG Hai2, LIN Yushi1, ZHANG Meiliang1, WANG Fuxing1, R. L. Edwards2, WANG Hua1 & RAN Jingcheng3 1. The Karst Dynamic Laboratory, IKG, CAGS, Guilin 541004, China 2. Geology and Geophysics Department, Minnesota University, MN55455, USA 3. The Management of Maolan National Nature Reserve, Libo 558400, China | 2005 | Science China Earth Sciences2005，48，4： | 23 |
| 3 | High- and Ultrahigh-pressure Metamorphism and Retrogressive Textures of Gneiss in the Donghai Area——Evidence from gneisses in drillhole ZK2304显示文摘In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamorphic reactions. In addition to garnet, jadeititic-clinopyroxene and rutile, other peak stage (M2) minerals in some gneisses include phengite, aragonite and coesite or quartz pseudomorphs after coesite. The typical peak-stage mineral assemblages in gneisses are characterized by garnet + jadeitic-clinopyroxene + rutile + coesite, garnet + jadeitic-clinopyroxene + phengite + rutile ± coesite and garnet + jadeitic-clinopyroxene + aragonite + rutile ± coesite. The grossular content (Gro) in garnet is high and may reach 50. 1 mol%. The SiO2 content of phengite ranges from 54.37% to 54.84% with 3.54-3.57 p.f.u. Quartz pseudomorphs after coesite occur as inclusions in garnet.The gneisses of the Donghai area have been subjected to multistage recrystallization and exhibit a closewise P-T | LIU Fulai, XU Zhiqin, XU Huifen and YANG Jingsui Institute of Geology, CAGS, 26 Baiwanzhuang Rd., Beijing 100037 Zhu Xiling | 1999 | Acta Geologica Sinica(English Edition)1999，73，3： | 12 |
| 4 | Post-Mesozoic Transformation of Tectonic Domain in Southeastern China and Its Geodynamic Mechanism显示文摘Since the Mesozoic and Cenozoic, a transformation from a Tethyan Himalayan tectonic domain into a circum Pacific tectonic domain from Indosinian to Yanshanian is indicated in this paper, resulting in conspicuous changes in geophysics, tectono magmatic distribution, lithofacies and paleo geography, tectonic system in southeastern China. Tectonic analysis shows that the tectonic framework resulted from the compounding, transforming and superimposing of the two tectonic domains. The geodynamic mechanism of the transformation is mainly shown as the transverse and longitudinal heterogeneity of lithosphere, and the exchange between the crust and the mantle. | Wu Ganguo Zhang Da Faculty of Earth Sciences and Mineral Resources, China University of Geosciences, Beijing 100083, China Chen Bailin Institute of Geomechanics, CAGS, Beijing 100081, China Wu Jianshe Institute of Geological Survey of Fujian Pr | 2000 | Journal of Earth Science2000，19，3： | 12 |
| 5 | ^(207)Pb/^(206)Pb Zircon Dating of the Huangtuling Hypersthene-Garnet-Biotite Gneiss from the Dabie Mountains, Luotian County, Hubei Province, China: New Evidence for Early Precambrian Evolution显示文摘The Huangtuling hypersthene-garnet-biotite gneiss at Luotian County, Hubei Provine, is a typicalgranulite-facies rock of the Dabie Group Complex in the Dabie orogenic belt. Investigations on the morphology andoccurrence of zircons and their internal structures shown in the thin sections lead to the recognition of three types ofzircons, which are in good agreement with the types identified on the basis of morphology, colour and external fea-tures from the related zircon concentrates. The observation of zircons in the rock reveals that part of type 1 zirconsshow signs of a double-layered structure. The interval part existed in the protolith prior to the granulite-facies meta-morphism. Type 2, the prismatic zircons which mainly occur in garnet and hypersthene are metamorphic minerals ofthe granulite-facies metamorphism. Type 3, the round multifaceted zircons in felsic minerals and biotite, are proba-bly attributed to a later geological event related to migmatization. The 207Pb/206Pb zircon dating by direct evaporationon (thermal evaporation ion mass spectrometer) yields ages ranging from 2814 Ma to 1992 Ma. The age discrepancyamong these different zircon types is conspicuous. The yellow-brown(type 1) zircons give ages of 2814±29 Ma to2527±6 Ma, the prismatic euhedral zircons (type 2), 2456±7 Ma to 2254±4 Ma, and the round multifaceted zircons(type 3), 1992±10 Ma. The results are geologically interpreted in consideration of the complicated behaviours of zir-cons during Precambrian geological evolution of the Dabie area. (1) If the protolith of the gneiss is a sedimentaryrock, then type 1 zircons are clastic ones and the ages 2814±29 Ma and 2811±27 Ma may reflect the minimum age ofthe rocks of its source region. also the first geological event in the area. Sedimentation of the protolith occurred be-tween 2814 Ma and 2527 Ma, probably close to 2814 Ma. If the protolith is a volcanic rock, then the formation age ofthe supracrustal rocks of the Dabie Group Complex is around 2814 Ma. The age 2456±7 Ma reflects the time whenthe granulite-facies metamorphism took place. The later migmatization event is dated at aboat 1992±10 Ma, and isprobably the latest early Precambrian event in the area. The present work provides geochronological evidence for the existence of the Dabie Archaean craton, whichhad probably experienced 3 or 4 geological events during its early Precambrian evolution. | JIAN Ping YANG Weiran and ZHANG Zichao Institute of Geology,CAGS,26 Baiwanzhuang Rd, Beijing 100037 China University of Geosciences, Wuhan, Hubei 430074 Yichang Institute of Geology and Mineral Resources, CAGS, Yichang, Hubei 443003 | 1999 | Acta Geologica Sinica(English Edition)1999，73，1： | 12 |
| 6 | Discovery of low grade metamorphic volcanic rock sheets within UHP in Dabie Mts. and its implications显示文摘THE ultrahigh-pressure metamorphic zone (UHP), outcropping in the central and southernDabie Mts. with an area of about 1000 km^2, may be the largest one in the world. The forma-tion and exhumation mechanism of the UHP rocks become a hot point in the study of continen-tal orogen. The first finding of the Shiqiao structural window, which is composed of low | DONG Shuwen, WANG Xiaofeng and HUANG Dezhi1. Chinese Academy of Geological Sciences (CAGS), Beijing 100037, China 2. Institute of Geomechanics of CAGS, Beijing 100081 China 3. Anhui Institute of Geological Sciences, Hefei 230001 | 1997 | Chinese Science Bulletin1997，42，14： | 10 |
| 7 | CH_4-rich fluid inclusions in the Yushigou mantle peridotite and their implications, North Qilian Mountains, China显示文摘Studies were carried out on the early phase of fluid inclusions which occur in residual olivines in harzburgite from the Yushigou ophiolitic mantle peridotite, the North Qilian Mountains. Components of these inclusions, analyzed by micro laser Raman spectroscopy, are dominantly CH4 (70%-95%) with minor H2, N2, H2S,CO2,C2H4,C2H6, and C3H6, but | SU Li, SONG Shuguang and WANG ZhihaiXi’an Institute of Geology and Mineral Resources, CAGS, Xi’an 710054, China | 1999 | Chinese Science Bulletin1999，44，21： | 10 |
| 8 | On the Geotectonics of Southern China显示文摘The tectonic nature of southern China has changed again and again in the Phanerozoic. In the Caledoniancycle, there existed three tectonic units——the Yangtze paraplatform, Indosinian-South China Sea paraplatformand Caledonian South China fold belt, of which the last unit is not a collisional orogenic belt but ascissor-shaped aulacogen-type geosyncline opening towards Yunnan and Vietnam. In the Indosinian cycle,South China belonged to the Tethyan tectonic domain, and no abyssal oceanic basin existed there. Since theLate Triassic, especially in the Yanshanian orogenic stage, it became a component part of the peri-Pacificcontinental-margin activation belt of eastern Asia. No Alpinc-type orogenic belt occurs in the interior of thecontinent of southern China. | Ren Jishun Institute of Geology,CAGS,Beijing Xie Guanglin | 1991 | Acta Geologica Sinica(English Edition)1991，65，2： | 10 |
| 9 | Constraints on the Archean atmospheric oxygen and sulfur cycle from mass-independent sulfur records from Anshan-Benxi BIFs, Liaoning Province, China显示文摘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 34S/δ 33S/δ 32S) for sulfides bedded in the Archean (~2.7 Ga) BIFs, in Anshan-Benxi area of Liaoning Province has been measured. The value of △33S varies from -0.89‰ to +1.21‰, which shows very obvious mass-independent fractionation (MIF) signatures. These non-zero △33S 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 △33S value, however, Superior-type BIFs which are far away from the volcanic center have positive △33S value. The δ 34S 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). | 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 Isotope Geology, CAGS, Beijing 100037, China | 2007 | Science China Earth Sciences2007，50，10： | 9 |
| 10 | Deep Tectonic Processes and Superaccumulation of Metals Related to Granitoids in the Nanling MetaUogenic Province,China显示文摘The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze and | PEI Rongfu, WANG Ping’an, and PENG Cong Institute of Mineral Deposits, CAGS, 26 Baiwanzhuang Rd., Beijing 100037 Institute of Geomechanics, CAGS, Beijing 100081 | 1999 | Acta Geologica Sinica(English Edition)1999，73，2： | 8 |
| 11 | Genesis of Yangla Banded Skarn-Hosted Copper Deposit in Tethys Orogenic Belt of Southwestern China显示文摘INTRODUCTIONTheYanglacopperdepositishostedbybandedskarn,whichwastraditionalyconsideredtohavebeenformedbycontactmetasomaticpro... | Zhan Mingguo Lu Yuanfa Yichang Institute of Geology and Mineral Resources, CAGS, Yichang 443003 Dong Fangliu Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083 Chen Kaixu Wei Junqi Yichang Institute of | 1999 | Journal of Earth Science1999，18，1： | 6 |
| 12 | “地壳异常压力”学术研讨会显示文摘延用至今的地质作用深度测算方法 ,即重力 /密度法 ,是基于“地下岩石处于静水压力状态” (Heim,1978)和“地下某一深处的垂直压力等于上覆岩石柱的总重量” (ДИННИК,1937)两个理论假设。下面刊登的是“地壳异常压力学术研讨会”专家们的发言 (北京 ,2 0 0 0 . 2 )。到会专家对上述假设和测算方法提出了不同见解 ,指出 ,浅部地壳直至地幔深处的岩石都是固体状态 ,地下的压力是极不均匀的 ,所以对地壳中的地质作用深度的测算必须把所处岩石看作固体 ,并依据固体物理理论 ,也就是说 ,除重力之外 ,构造力、瞬时压力、结晶力、变质作用、岩石相变等都会产生局部巨大的异常压力。因此 ,应该对地壳异常压力进行深入研究以建立更具普适性的深度测算公式。专家们还认为 ,对在全球具有重要地位的大别超高压变质带的形成深度 ,我国科学家认为是 32 km左右 ,属壳内成因 ,并提供了测算数据 ,但该项研究还应深化。 | CHEN Qing-xuan,REN Xi-fei,LU Gu-xian: ( Institute of Geomechanics,CAGS,Beijing 1 0 0 0 81 ,China) ( 2 ) DONG Shen-bao,LIU Rui-xun,CHEN Jing: ( Departmentof Geology,Peking University,Beijing 1 0 0 871 ,China) ( 3 ) WANG Fang-zheng:( Chinese University of Geosciences,Wuhan 4 3 0 0 74 ,China) ( 4) REN Ji-shun,LITing-dong,LIU Dun-yi: ( Institute of Geology,CAGS,Beijing 1 0 0 0 3 7,China) ( 5) ZHAIYu-sheng:( Chinese University of Geosciences,Beijing1 0 0 0 83 ,China) ( 6) ZHANG Bing-xi:( Ministry of Land and Resources,Beijing1 0 0 0 3 5,China) ( 7) SHAO Li-qin:( Ministry of Science and Technology,Beijing 1 0 0 0 3 8,China) | 2000 | 地质力学学报2000，6，3： | 6 |
| 13 | Isotopic Geochronological Evidence for the Caledonian Xiongdian Eclogite in the Northwestern Dabie Mountains,China显示文摘A typical HP/MT (high pressure/medium temperature) eclogite from Xiongdian, northwestern Dabie Mountains, has been geochronologically studied using the single-zircon U-Pb, 40Ar-39Ar and Sm-Nd methods. Prismatic zircons occurring as inclusions within garnets define a minimum crystallization age of 399.5±1.6 Ma. 40Ar-39Ar dating on amphibole gives a plateau age.of 399.2 ± 4 Ma, which is interpreted as a retrogression age of amphibolite facies. This integrated study enables us to conclude that the age of high-pressure metamorphism is older than 399.5 ± 1.6 Ma, suggesting Caledonian collision between the North China and Yangtze plates. Round zircon within the aggregate of quartz and muscovite gives a concordant age of 301± 2 Ma, reflecting a later retrogression event. An age profile of post-eclogite metamorphism is documented, including amphibolite facies metamorphism at 399.2 Ma shortly after eclogitization and later retrogressive metamorphism at 301 Ma. Sm-Nd mineral isochron of garnet+omphacite | Jian PingYichang Institute of Geology and Mineral Resources. CAGS, Yichang City,Hubei Province 443003Yang Weiran China University of Geosciences, Wuhan, HubeiLi Zhichang Yichang Institute of Geology and Mineral Resources, CAGS, Yichang, HubeiZhou Huifang Tianjin Instutite of Geology and Mineral Resources, CAGS, Tianjin Zhu Xiling | 1997 | Acta Geologica Sinica(English Edition)1997，71，4： | 4 |
| 14 | Terminal Precambrian Palaeogeographic Framework of China显示文摘The original locations and relationships of four plates within the mainland of China from 800 to 600 Ma during the terminal Precambrian were reconstructed based on the palaeomagnetic and geological data. The Tarim, Yangtze and Cathaysian plates were once linked (in 800-700 Ma) and located in the same low-latitude zone of the northern hemisphere. But later, in 700-600 Ma, the Tarim plate was separated from the Yangtze-Cathaysian plate. The Sino-Korean plate was always far away from the Yangtze plate, both being separated by oceanic crust, and lay in the high-latitude zone of the northern hemisphere.The above-mentioned palaeogeographic framework directly led to complete differences in respect to distribution of low-latitude glaciation, sedimentary facies, palaeoclimate, palaeobiogeography and stratigraphic sections between the North and South China domains during the terminal Precambrian. | Qiao Xiufu, Ma Lifang Geological Institute, CAGS, Beijing, and Zhang Huimin Tianjin Institute of Geology and Mineral Resources, CAGS, Tianjin Jia Zhongpeng | 1989 | Acta Geologica Sinica(English Edition)1989，63，2： | 2 |
| 15 | Study on Mineralization Age of Xiaoban Gold Deposit, Fujian Province显示文摘The Xiaoban gold deposit is a large size deposit recently found in middle area of Fujian Province. It belongs to magmatic hydrothermal type occurred in Mayuan Group metamorphic rocks of Middle Proterozoic and is controlled by low angle fault (detachment) structures. The contents of Au in Mayuan Group metamorphic rocks, Caledonian Indosinian deformed granite and early Yanshanian granite are higher with Au enrichment coefficient of 2.06-5.68, 5.11 and 6.67 than those in other geological bodies. And the higher enrichment coefficients (>2) of Ag, S, Sn and Te are similar to those of gold ore. Meanwhile, the distribution of Au in Mayuan Group metamorphic rocks and early Yanshanian granite with a low D value (0.58 and 0.67) is favorable to gold mineralization. REE characteristics of gold ore, ratios of (LREE/HREE), (La/Sm) n, (Yb/Lu) n, (La/Tb) n and (Sm/Nd) n are similar to Mayuan Group metamorphic rocks, only non or little normal Eu abnormal of ore is dissimilar to metamorphic rocks. The δ ( 34 S) of the gold ore, with a high homogenization, is (-4.7×10 -3 )-(-2.7×10 -3 ). The study of inclusion indicates 180-249 ℃ of mineralization temperature, 3.69 %-11.81 % of salinities and 0.869-0.991 g/cm 3 of densities of mineralization fluid. Based on hydrogen and oxygen isotope ( δ ( 18 O)=11.0×10 -3 -11.7×10 -3 , δ (D)=(-48×10 -3 )-(-62×10 -3 )) and initial w ( 87 Sr)/ w ( 86 Sr) =0.715,combining to the analysis of geological history, regional metamorphism and magamtic activity, the authors confirm that the source for the ore fluid was mainly from magmatic, partly from metamorphic water, and with a little influence of meteoric water. Isotopic dating made on Rb Sr isochron age of 182 Ma, by using alteration minerals of gold ores from the deposit, indicates that the mineralization occurs in early Yanshanian epoch. This is close to the age of 187 Ma of the Anchun magmatite with a similar alteration and gold mineralization to the Xiaoban gold deposit. The age of early Yanshanian epoch of the Xiaoban gold is indentical with the characteristics of southern China gold metallogenic belt and the geotectonic evolution of the transition from paleo Asian system and paleo Tethyan system to paleo Pacific active continental margin in eastern Asia. | Chen Bailin Institute of Geomechanics, CAGS, Beijing 100081 Wu Ganguo Faculty of Earth Sciences and Mineral Resources, China University of Geosciences, Beijing 100083 Zhang Da Institute of Geomechanics, CAGS, Beijing 100081 Huang Rensheng West Fujian Geological Party of FBGMRE, Sanming 365000 Wu Jianshe Fujian Bureau of Geological and Mineral Resources Exploration, Fuzhou 350003 | 2002 | Journal of China University of Geosciences2002，13，3： | 2 |
| 16 | Tissue engineering:a new paradigm for periodontal regeneration based on molecular and cell biology显示文摘 | Bartold PM Mcculloch CAG Narayanan AS | 2000 | Periodontology2000，2000，24： | 2 |
| 17 | Percutaneous Nephrolithotomy: Variables That Influence Hemorrhage显示文摘 | Burak Turna Oktay Nazli Serkan Demiryoguran Rashad Mammadov Cag Cal | 2007 | Urology2007，，4： | 2 |
| 18 | Cesium accumulation by bacterium Thermus sp. TibetanG7:hints for biomineralization of cesium-bearing geyserite in hot springs in Tibet,China显示文摘The bacterium Thermus sp. TibetanG7, isolated from hot springs in Tibet, China, was examined for the ability to accumulate cesium from solutions. Environmental conditions were simulated and the effects of pH, K+, Na+ and K+-regimes were then studied to determine the possible role of the bacterium in the formation of cesium-bearing geyserite around these hot springs. In despite of the inhibition of K+ and Na+, the bacterium Thermus sp. TibetanG7 revealed noticeable accumulation of cesium from solutions, with maximum accumulations of 53.49 and 40.41 μmol Cesium/g cell dry weight in Na+ and K+ inhibition experiments, respectively. The accumulation of cesium by this microorganism is rapid, with 40%―50% accumulated within the first 5 min. K+-deficient cells showed a much higher capacity of cesium accu- mulation compared with K+-sufficient cells. It is evident that the bacteria within the genus thermus play a significant role in the cesium assembly. The formation of cesium-bearing geyserite is also considered. | WANG HaiLei1,2,3, ZHENG MianPing1,2,3 & HUANG XiaoXing4 1 Institute of Mineral Resources, Chinese Academy of Geological Sciences (CAGS), Beijing 100037, China 2 R&D Center for Saline Lake and Epithermal Deposits, CAGS, Beijing 100037, China 3 Open Laboratory of Saline Lake Resourses and Environment, CAGS, Beijing 100037, China 4 Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100081, China | 2007 | Chinese Science Bulletin2007，52，19： | 2 |
| 19 | Double Convective Hydrothermal System beneath Massive Sulfide Orebody in Gacun Deposit,Southwestern China显示文摘The Gacun Kuroko-type deposit, Southwestern China, is hosted in rhyolitic rocks associated with the underlying mafic rocks occurred in the ~1000 m deep fault-hounded basin within the intra-arc rifting zone which formed on the Triassic Yidun island-arc. Two vertically separated alteration systems are recognized: one is conformable or semiconformable alteration zone developed in ~150 m thick mafic unit 1-1.5 km below the massive sulfde orehody; the other is discordant alteration pipe directly surrounded around stockwork ore within rhyolitic unit. The lower conformable alteration zone extending for several kilometers along strike is characterized by silicification and epidotization which result in the development of quartz vein and quartz-epidote vein systems in mafic lava flows and replacement of primary minerals and groundmass in spilitized mafic volcanics and dikes by quartz, epidote-group minerals and sodic plagiocluse. Sulfides often occur in the vein system and altered mafic volcanics. Quartz | Hou ZengqianInstitute of Mineral Deposits, CAGS, Beijing 100037Mo Xuanxue Department of Geology and Mineral Resources, China University of Geosdences, Beijing 100083Urabe Tetsuro Geological Survey of Japan, Higash 1-1-3, Tsukuba, Ibaraki, 305, Japan | 1995 | Journal of Earth Science1995，14，2： | 2 |
| 20 | Paleosubmarine Volcanism and Mineralization from North Qilian Mountains显示文摘INTRODUCTIONNorthQilianMountainshasundergonethreekindsoftec-tonicsystemssinceProterozoic,namelycontinentalrift,platetectonica... | Xia Linqi Xia Zuchun Ren Youxiang Xu Xueyi Peng Ligui Institute of Geology and Mineral Resources, CAGS, Xi ’an 710054 | 1999 | Journal of Earth Science1999，18，1： | 2 |
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