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| 1 | 内蒙古中部四子王旗大庙岩体时代及成因显示文摘华北北缘的内蒙古中部地区出露大量晚古生代-早中生代花岗岩类,在空间上构成一条巨大的东西向花岗岩带。四子王旗大庙岩体作为一个典型的代表,以花岗闪长岩为主,其内部普遍发育暗色微粒包体(MMEs),是认识花岗岩岩石成因和演化的关键。本文对包体及寄主岩进行了同位素测年、岩相学、矿物化学、全岩主量元素和微量元素分析。寄主岩石中的锆石LA-ICPMS U-Pb年龄平均为265±7Ma(2σ),包体中单颗粒黑云母Rb-Sr年龄为253±5Ma(MSWD=0.85),属晚二叠世-早三叠世岩浆活动的产物。包体具塑性外形及岩浆结构,存在多种不平衡矿物组合;MME中的斜长石An组分及黑云母斑晶中MgO成分呈多期震荡,同时总体上均显示出幔部高于核、边部的特征,暗示斑晶可能为围岩捕虏晶,这种相似的成分变化指示包体与寄主岩相互作用引起的结晶环境改变,标志着岩浆成分的变化,是岩浆混合的标志之一;主量和微量数据进一步证明岩体的岩浆混合成因。Rb/Sr-K/Rb变化关系反映包体非结晶分异或黑云母堆晶的产物,而Ce/Pb-Ce、Ba-δEU和P_2O_5-δEu图及其他微量元素比值图等均表明花岗闪长岩体发生了岩浆混合作用,这也得到岩浆物理化学条件的支持。岩浆底侵和岩浆混合作用是该区岩体形成的主要机制和方式。岩石地球化学特征表明该岩体不同于加厚地壳和俯冲洋壳熔融的TTG和埃达克质岩石,而黑云母矿物化学和岩石地球化学显示其构造背景很可能为同碰撞环境。 | 章永梅 张华锋 刘文灿 周志广 | 2009 | 岩石学报2009，25，12： | 63 |
| 2 | 川东北普光气田下三叠统飞仙关组白云岩成因——来自岩石结构与Sr同位素和Sr含量的证据显示文摘研究了川东北普光气田下三叠统飞仙关组白云岩储层的岩石结构Sr的含量和Sr同位素组成,讨论了它的成因,飞仙关组优质储层为成岩期埋藏交代白云化作用的产物,来自岩石结构和Sr同位素和Sr含量的证据包括如下几个方面:(1)与准同生白云岩比较,埋藏白云岩的岩石结构和Sr同位素和Sr含量地球化学特征与前者有显著差别;(2)飞仙关组所有各类碳酸盐岩(或矿物)具有早三叠世海水Sr同位素组成特征,^(87)Sr/^(86)Sr比值变化范围为0.706588~0.708187,覆盖了全球早三叠世海水Sr同位素的变化范围(0.7076~0.7078),平均值0.707656与全球早三叠世平均值(0.707743)基本一致;(3)埋藏白云岩^(87)Sr/^(86)Sr比值变化范围为0.707122~0.707419,平均值0.707421,都略低于全球早三叠世海水Sr同位素变化范围和平均值,但与已报道的川东北早三叠世飞仙关期海水Sr同位素变化范围(0.707330~0.707383)和平均值(0.707350) 都非常接近,说明白云石化流体具有强烈的川东北地区早三叠世飞仙关期海水Sr同位素组成特征;(4)综合岩石结构、Sr同位素和Sr含量地球化学特征,证明飞仙关组白云岩储层为成岩期埋藏交代作用产物,白云石化流体来自地层中高Sr和高盐度的海源地层水。 | 郑荣才 文华国 郑超 罗平 李国军 陈守春 | 2009 | 岩石学报2009，25，10： | 24 |
| 3 | 金川铜镍矿床隐伏富铜矿体成因研究及其深部找矿意义显示文摘金川矿床赋存于富橄榄石超镁铁质岩中,是目前世界第三大在采铜镍硫化物矿床。经过多年开采,如何在深、边部找到新的替代资源问题显得越来越重要。通过对金川矿床富铜隐伏矿体的矿体特征、矿石特征和矿石特殊地球化学特性等方面进行分析研究,特别是从空间立体对其矿化规律进行总结,并与其附近Ⅱ1#主矿体进行对比,指出该类型矿体既有岩浆熔离作用的特点,又有后期改造作用的特征,其形成经历了三个阶段:富含Cu、PGE岩浆深部熔离-脉动贯入、构造活化富集和后期热液叠加。同时探讨了来源于地幔深部的高镁玄武质岩浆,在深部岩浆房和阶段岩浆房熔离分异过程中,富镍岩浆和矿浆之间存在富铜岩浆。此外,Pb同位素表明,该隐伏富铜矿体形成时间为8亿年左右,早于块状特富矿;Pb、S同位素表明,该矿体主要来源于地幔,但曾被少量地壳物质混入。最后指出铜镍硫化矿床的成因是复杂多样的,在金川矿床深边部寻找新型矿体,尤其是富铜矿体的前景很大,而F_6断层可能是富铜隐伏矿体岩浆通道和Ⅱ1#主矿体岩浆的深部侵位通道之一。 | 高亚林 汤中立 宋谢炎 田毓龙 孟远志 | 2009 | 岩石学报2009，25，12： | 23 |
| 4 | 河南土门萤石脉型钼矿床流体包裹体研究及成因探讨显示文摘河南方城土门萤石脉型钼矿床位于栾川断裂北侧的华熊地块东南部。矿体呈断续的脉状、似层状、透镜状产于花岗斑岩外接触带,赋矿构造为大理岩与片岩之间的层间断层。矿石主要由萤石、硫化物和碳酸盐等矿物组成。矿脉穿插关系、矿石组构和矿物组合显示了4阶段矿化:分别以白色萤石(Ⅰ阶段)、紫色萤石-辉钼矿(Ⅱ阶段)、辉钼矿多金属硫化物(Ⅲ阶段)以及碳酸盐(Ⅳ阶段)为标志。各阶段萤石中流体包裹体可分为4类:NaCl-H_2O型(W类)、CO_2-H_2O-NaCl型(C类)、纯CO_2型(PC类)及含子晶包裹体(S类)。冷热台测试显示,Ⅰ阶段均一温度为300~420℃,峰值为360~410℃,Ⅱ阶段均一温度180~380℃,峰值为220~300℃;Ⅰ阶段流体盐度高达49.68 wt%NaCl eqv.,Ⅱ阶段则不高于13.07 wt%NaCl eqv.。从早到晚,W类包裹体平均密度由0.88g/cm^3减小到0.84g/cm^3,C类包裹体CO_2的平均密度由0.66g/cm^3增高到0.82g/cm^3。总体来说,土门萤石-钼矿床形成于中高温、高盐度、富CO_2和F的流体系统,成因上归属于大陆背景的浆控脉状热液成矿系统。 | 邓小华 糜梅 姚军明 | 2009 | 岩石学报2009，25，10： | 17 |
| 5 | 化学杂交剂GENESIS对小麦的杀雄效果显示文摘采用 4个品种 ,4个剂量 ,2个表面活性剂的裂区试验和 2个品种的异地试验 ,对新型化学杂交剂GENESIS诱导小麦雄性不育的效果进行了研究。结果表明 :( 1)GENESIS杀雄彻底 ,2 0kg/hm2 以上剂量的不育率均超过 95 % ,3 0、 5 0kg/hm2 剂量达到或接近 10 0 % ,且没有诱导小麦雄性不育的专一性 ;( 2 )不育率为 95 %以上的人工饱和授粉结实率和自然授粉结实率最高达 6 7 6 5 %和 49 83% ;( 3) 5 0kg/hm2 剂量下 ,添加表面活性剂MON816 1的人工饱和授粉结实率比添加MON5 916 0的降低 18 9% ,差异显著。说明表面活性剂MON816 1对雌蕊的活力具有一定影响 ;( 4)相同基因型在两个地点的不育率和自然授粉结实率差异不显著 。 | 高庆荣 于金凤 刘保申 孙兰珍 | 2001 | 山东农业大学学报(自然科学版)2001，32，1： | 17 |
| 6 | Water in the upper mantle and deep crust of eastern China: concentration, distribution and implications显示文摘Understanding the concentration and distribution of water in the Earth's mantle plays a substantial role in studying its chemical, physical and dynamic processes. After a decade of research, a comprehensive dataset of water content in upper-mantle samples has been built for eastern China, which is now the only place with water-content data from such diverse types of natural samples, and provides an integrated picture of the water content and its distribution in the upper mantle at a continental scale. The main findings include the following:(i) the temporal heterogeneity of the water content in the lithospheric mantle from early Cretaceous(~120 Ma) to Cenozoic(<40 Ma) was tightly connected with the stability of the North China Craton(from its destruction to its consolidation);(ii) the heterogeneous water content in the Cenozoic lithospheric mantle beneath different blocks of eastern China was not only inherited from tectonic settings from which they came, but was also affected later by geological processes they experienced;(iii) the distinct water content between the lowermost crust and lithospheric mantle of eastern China and its induced rheological contrast at the base of the crust indicate that the continental crust–mantle boundary could behave either in a coupled or decoupled manner beneath different areas and/or at different stages;(iv) the alkali basalts of eastern China demonstrate a heterogeneous distribution of water content in the mantle;local and regional comparisons of the water content between the lithospheric mantle and basalts' source indicate that the Cenozoic alkali basalts in eastern China were not sourced from the lithospheric mantle.Instead, the inferred high water contents in the mantle sources suggest that the Cenozoic eastern China basalts were likely sourced from the mantle transition zone(MTZ); and(v) both oceanic and continental crusts may carry a certain amount of water back into the deep mantle of eastern China by plate subduction.Such recycled crustal materials have not only created a local water-rich zone, but have also introduced crustal geochemical signatures into the mantle, both accounting for crustal geochemical imprints in the intra-plate magmatic rocks of eastern China. | Qun-Ke Xia Jia Liu István Kovács Yan-Tao Hao Pei Li Xiao-Zhi Yang Huan Chen Ying-Ming Sheng | 2019 | National Science Review2019，6，1： | 16 |
| 7 | 不同基因型小麦雄性不育的化学诱导研究显示文摘以 2 1个小麦品种和化学杂交剂Genesis的不同剂量为处理 ,采取裂区设计的方法 ,研究了Genesis的杀雄效果及其不同基因型小麦对Genesis反应的遗传差异 .结果表明 ,Genesis诱导小麦雄性不育效果具有广谱性 ,在 3kg.hm-2 剂量下大部分品种的不育率达到 99%以上 ,但不同品种敏感性不同 ,其不育率差异显著 .本文还对Genesis的药害进行了讨论 . | 吕德彬 闫滋福 程西永 许海霞 徐巧玲 | 2000 | 河南农业大学学报2000，34，1： | 15 |
| 8 | Orogenic and Anorogenic Granitoids in the Altay Mountains of Xinjiang and Their Discrimination Criteria显示文摘On the basis of field geological studies of the granotoids in the region, mineralogical, petrological, geochemical(including stable isotope geochemical) and isotopic geochronological investigations were carried out on selected representative granitic bodies of various types. The authors have concluded that, apart from the bodies of the orogenic granitoid series, there also exist intrusions of the anorogenic granitoid series in the region. The intrusives of the two series were formed not only in different ages and tectonic environments, but also were derived from different sources of materials. Moreover, they are associated with different mineralizations, belonging to different minerologenetic series(Cheng et al., 1983). They show distinctly a series of discriminative criteria. The problems under discussion in the present paper are of important theoretical and practical significance in the studies of granites of the orogenic belt, particularly the studies of the genesis and related metallogeny of the granites of the region. | Zou Tianren Institute of Mineral Deposits, Chinese Academy of Geological Sciences, Beijing Chao Huizhi and Wu Baiqing Xinjiang Institute of Geology, Ministry of Metallurgical Industry Urumqi, Xinjiang Jiang Minxi | 1989 | Acta Geologica Sinica(English Edition)1989，63，1： | 14 |
| 9 | Cyclooxygenase-2 plays a central role in the genesis of pancreatitis and associated lung injury显示文摘BACKGROUND: The exact mechanism by which cyclooxy- genase-2 (COX-2) promotes inflammation in pancreatitis in obscure. This study was undertaken to investigate the role of COX-2 inhibition in an animal model of pancreati- tis , a disease process characterized by a systemic inflamma- tory response and ensuing neutrophil-mediated lung injury. METHODS: Pancreatitis was induced in 24 Sprague-Daw- ley rats by intraperitoneal injection of 20% L-arginine (500 mg/100 g body weight). The animals were randomized into 3 groups (8 rats in each group); controls and rats with pancreatitis intravenously resuscitated with either normal saline (0.9% NaCl 3 ml/kg) at 24 and 48 hours or COX-2 inhibitor (parecoxib 1 mg/kg). Pancreatic and lung inju- ries were assessed histologically. Lung injury was assessed utilizing wet;dry ratio and myeloperoxidase activity to in- dicate pulmonary neutrophil infiltration. A Western blot was used to determine COX-2 protein expression in pancrea- tic tissue. RESULTS: The animals treated with COX-2 inhibitors dis- played significantly less pancreatic and lung injuries than their normal saline counterparts. Histological pancreatic and lung injury scores were significantly reduced (P <0.05) in the COX-2 treated group. Lung wet: dry ratios were sig- nificantly improved and pulmonary neutrophil infiltration was attenuated in the COX-2 group (P<0.05). Western blot analysis confirmed attenuated COX-2 protein expression. CONCLUSION: This study shows, for the first time in a rat model, that adjuvant COX-2 inhibition significandy attenu- ates the severity of both pancreatitis and its associated sys- temic inflammatory response and end-organ injury. | Gavin O'Brien Conor J Shields Desmond C Winter John P Dillon | 2005 | Hepatobiliary & Pancreatic Diseases International2005，4，1： | 12 |
| 10 | GENESIS诱导小麦雄性不育性与花药组织呼吸关系的初步研究显示文摘对小麦小孢子发育的各个时期,经GENESIS处理的和未处理的植株花药的总呼吸活性 Vt 、细胞色素途径呼吸活性 ρ′Vcyt 和交替途径实际呼吸活性 ρValt 进行了比较研究,结果表明,在各时期,处理植株花药的Vt呼吸均低于未处理植株,尤以单核期最为明显;在小孢子减数分裂期、四分体期和单核期,处理小麦植株花药的ρ′Vcyt均明显降低,而在小孢子减数分裂期和四分体期ρValt出现明显升高.结论认为,由呼吸过程中电子传递途径运行的改变而造成处理植株花药呼吸代谢的紊乱,可能是GENESIS诱导小麦雄性不育发生的重要原因. | 方正武 姚亚琴 张改生 刘宏伟 王军卫 | 2004 | 西北植物学报2004，24，6： | 12 |
| 11 | Fluid Inclusion and H-O Isotope Geochemistry of the Phapon Gold Deposit, NW Laos: Implications for Fluid Source and Ore Genesis显示文摘The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brittle fault system. There are three types of primary ore including auriferous calcite vein type, disseminated type, and breccia type, and the first two are important in the Phapon gold deposit. Based on fluid inclusion petrography and microthermometry, three types of primary fluid inclusions including type 1 liquid-rich aqueous, type 2 vapor-rich aqueous and type 3 daughter mineralbearing aqueous were identified in hydrothermal calcite grains. The ore-forming fluids are normally homogeneous, as indicated by the widespread type 1 inclusions with identical composition. The coexistence of type 1 and type 2 inclusions, showing similar final homogenization temperature but different compositions, indicate that fluid immiscibility did locally take place in both two types of ores. The results of microthermometry and H-O isotopes geochemistry indicate that there are little differences on ore-fluid geochemistry between the auriferous calcite vein-type and disseminated type ores. The oreforming fluids are characterized by medium-low temperatures(157–268 oC) and low salinity(1.6 wt.%–9.9 wt.% NaCl eq.). It is likely to have a metamorphic-dominant mixed source, which could be associated with dehydration and decarbonisation of Lower Permian limestone and Middle–Upper Triassic sandstones during the dynamic metamorphism. The fluid-wallrock interaction played a major role, and the locally occurred fluid-immiscible processes played a subordinate role in gold precipitation. Combined with the regional and ore deposit geology, and ore-fluid geochemistry, we suggest that the Phapon gold deposit is best considered to be a member of the epizonal orogenic deposit class. | Linnan Guo Shusheng Liu Lin Hou Jieting Wang Meifeng Shi Qiming Zhang Fei Nie Yongfei Yang Zhimin Peng | 2019 | Journal of Earth Science2019，30，1： | 11 |
| 12 | TROPICAL CYCLONE GENESIS EFFICIENCY:MID-LEVEL VERSUS BOTTOM VORTEX显示文摘Cloud resolving Weather Research and Forecasting(WRF)model simulations are used to investigate tropical cyclone(TC)genesis efficiency in an environment with a near bottom vortex(EBV)and an environment with a mid-level vortex(EMV).Sensitivity experiments show that the genesis timing depends greatly on initial vorticity vertical profiles.The larger the initial column integrated absolute vorticity,the greater the genesis efficiency is.Given the same column integrated absolute vorticity,a bottom vortex has higher genesis efficiency than a mid-level vortex.A common feature among these experiments is the formation of a mid-level vorticity maximum prior to TC genesis irrespective where the initial vorticity maximum locates.Both the EMV and EBV scenarios share the following development characteristics:1)a transition from non-organized cumulus-scale(~5 km)convective cells into an organized meso-vortex-scale(~50 to 100 km)system through upscale cascade processes,2)the establishment of a nearly saturated air column prior to a rapid drop of the central minimum pressure,and 3)a multiple convective-stratiform phase transition.A genesis efficiency index(GEI)is formulated that includes the following factors:initial column integrated absolute vorticity,vorticity at top of the boundary layer and vertically integrated relative humidity.The calculated GEI reflects well the simulated genesis efficiency and thus may be used to estimate how fast a tropical disturbance develops into a TC. | 葛旭阳 李天明 彭顺台 | 2013 | Journal of Tropical Meteorology2013，19，3： | 10 |
| 13 | THE C^(14) AGE AND CYCLE OF SEDIMENTATION OF SOME SALINE LAKES ON THE QINGHAI-XIZANG PLATEAU显示文摘On the Qinghai-Xizang Plateau, there are a number of inland lakes that are the highest above sea level and the largest of their kind in the world. Most of them are structural lakes, their genesis and formation being influenced by structural factors. Amongst them there are more than 100 saline lakes in which are accumulated inexhaustible minerals such as halite, glauber salt, strintium minerals, borate, lithium mineral and sylvine. | 黄麒 蔡碧琴 余俊青 | 1981 | Chinese Science Bulletin1981，26，1： | 8 |
| 14 | A New Model for the Genesis of Natural Gases--Multi-source Overlap, Multi-stage Continuity, Type Controlled by Main Source and Nomenclature by Main Stage (Ⅰ)--Multi-source Overlap and Type Controlled by Main Source显示文摘Based on the geochemical studies of natural gases in the past ten years in China, the authors have proposed a new model for their genesis--multi-source overlap, multi-stage continuity, main source-controlling type and nomenclature by the main stage.Multi-source refers to a diversity of material sources involved in the formation of natural gases, including abiogenic and biogenic material sources. In regard to biogenic sources, either oil-generating or coal-generating organic matter would produce gaseous hydrocarbon reservoirs of commercial importance. Generally, natural gases originating from these sources can overlap to form gas reservoirs. Under specific circumstances mantle-source abiogenic gases could overlap biogenic gases to form gas reservoirs. In nature, natural gases predominated by gaseous hydrocarbons may be formed from a single end-member source. However, multi-source overlap is more typical of the genesis of natural gases. | 徐永昌 沈平 | 1994 | Science China Chemistry1994，37，3： | 8 |
| 15 | 化学杀雄剂GENESIS诱导早熟禾雄性不育的初步研究显示文摘试用美国新近生产的化学杀雄剂 GENESIS对早熟禾进行雄性不育的初步研究。结果表明 ,参试的 4个品种瓦巴斯草地早熟禾、思托佩草地早熟禾、天祝扁秆早熟禾与莫诺波利草地早熟禾在生育期 Feekes标准 8.0~ 9.0时 ,用 GENESIS进行一次叶面喷施 ,在 1. 5kg/ hm2 和 2 .5kg/ hm2 的剂量下 ,天祝扁秆早熟禾的杀雄效果为 95%和 97% ,其它品种均为10 0 % | 赵桂琴 | 2000 | 草业科学2000，17，3： | 7 |
| 16 | Geochemical characteristics and origin of gases from the Upper,Lower Paleozoic and the Mesozoic reservoirs in the Ordos Basin,China显示文摘The Ordos Basin,the second largest sedimentary basin in China,contains the broad distribution of natural gas types.So far,several giant gas fields have been discovered in the Upper and Lower Paleozoic in this basin,each having over 1000×10 8 m 3 of proven gas reserves,and several gas pools have also been discovered in the Mesozoic.This paper collected the data of natural gases and elucidated the geochemical characteristics of gases from different reservoirs,and then discussed their origin.For hydrocarbons preserved in the Upper Paleozoic,the elevatedδ13C values of methane,ethane and propane indicate that the gases would be mainly coal-formed gases;the singular reversal in the stable carbon isotopes of gaseous alkanes suggests the mixed gases from humic sources with different maturity.In the Lower Paleozoic,theδ13C 1 values are mostly similar with those in the Upper Paleozoic,but theδ13C 2 andδ13C 3 values are slightly lighter,suggesting that the gases would be mixing of coal-type gases as a main member and oil-type gases.There are multiple reversals in carbon isotopes for gaseous alkanes,especially abnormal reversal for methane and ethane(i.e.δ13C 1 >δ13C 2 ),inferring that gases would be mixed between high-mature coal-formed gases and oil-type gases.In the Mesozoic,the δ13Cvalues for gaseous alkanes are enriched in 12C,indicating that the gases are mainly derived from sapropelic sources;the carbon isotopic reversal for propane and butane in the Mesozoic is caused by microbial oxidation and mixing of gases from sapropelic sources with different maturity.In contrast to the Upper Paleozoic gases,the Mesozoic gases are characterized by heavier carbon isotopes of iso-butane than normal butane,which may be caused by gases generated from different kerogen types. Finally,according toδ13C 1 -Ro relationship and extremely low total organic carbon contents,the Low Paleozoic gases would not be generated from the Ordovician source as a main gas source,bycontrast, the Upper Paleozoic source as a main gas source is contributed to the Lower Paleozoic gases. | HU AnPing 1 ,Li Jian 2 ,ZHANG WenZheng 3 ,LI ZhiSheng 2 ,HOU Lu 4 &LIU QuanYou 5 1 Department of Earth Sciences,Zhejiang University,Hangzhou 310027,China 2 Langfang Branch,Reasearch Institute of Petroleum Exploration and Development,PetroChina,Langfang 065007,China 3 Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi’an 710021,China 4 University of Petroleum,Beijing102249,China 5 PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China | 2008 | Science China Earth Sciences2008，51，S1： | 6 |
| 17 | Granulite Genesis and Tectonic Evolution in Tongbai Area:Single Zircon Evaporation Ages and Nd Isotopic Geochemistry显示文摘INTRODUCTIONTongbaiareainCentralChinaisanimportantregionforstudyinggenesisrelationbetweenQinlingorogenicbeltandDabieorogenicb... | Zhang Hongfei Gao Shan Zhang Li Zhong Zengqiu Ling Wenli Wang Linsen Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 | 1998 | Journal of Earth Science1998，17，3： | 6 |
| 18 | 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 |
| 19 | A New Model for the Genesis of Natural Gases——Multi-source Overlap, Multi-stage Continuity, TypeControlled by Main Source and Nomenclature by Main Stage (Ⅱ)——Multi-stage Continuity and Nomenclature by Main Stage显示文摘The generation of natural gases involves several stages and the various stages are of continuous transition. This is another feature of natural gas generation. The term 'multi-stage' is relative mainly to oil-generating threshold value and liquid window. The evolution of organic matter is affected by different epigene agencies and natural gases differing in geochemical properties such as biogenic gas (bacterial gas), thermocatalytic gas and pyrolytic gas could be produced at different stages of the evolution of organic matter. The proposal of bio-thermocatalytic transitional-zone gas presents a pattern of mutual linking and continuous transition of natural gases originated at different stages.In the genetic classification of natural gases, the nomenclature of a certain gas is based mainly on the epigene agency which is responsible for its formation, for example, biogenic gas, pyrolytic gas. That is the 'nomenclature by the main stage' described in this study. On account of the continuity of gas | 徐永昌 沈平 | 1994 | Science China Chemistry1994，37，4： | 5 |
| 20 | Geological characteristics,metallogenic background,and genesis of the Tongyu VHMS copper deposit in the west part of the North Qinling,Shaanxi Province显示文摘The Tongyu volcanic-hosted massive sulfide(VHMS) copper deposit is located in the west part of the North Qinling(NQL),Shaanxi Province.Here we report geological features and trace elemental characteristics of ores,mineralized rocks,and volcanic host rocks of this deposit.We also conducted in situ zircon U-Pb and Lu-Hf LA-ICP-MS dating and lithogeochemical study of the Meigou granodiorite,which is intruded in the south of the Tongyu mining district.It is inferred that the volcanic host rocks of the Tongyu Cu deposit belong to calc-alkaline island arc volcanic rocks,and the volcanic host rocks and the ore-forming materials share common material sources.During subduction of the Paleo-Qinling oceanic slab at around 472 Ma,high oxygen-fugacity aqueous fluid released by dehydration reaction of the subducting slab rose into the mantle wedge,leached Cu and other metal elements,and triggered partial melting of the mantle wedge.Associated with the ore-forming materials,the arc calc-alkaline magmas erupted and formed the Tongyu VHMS deposit.The weighted average zircon U-Pb age of the Meigou granodiorite is 439.3±3 Ma,suggesting its genesis is associated with the subduction event of the Paleo-Qinling oceanic plate around 440 Ma.In terms of the granitoid's geochemical characteristics,the Mg#,Ni,and Cr contents are high.REE show strongly fractionated patterns with unobvious Eu anomalies.Sr contents are high while Y contents are low,resulting in high Sr/Y ratios.Two-stage zircon Hf model ages mostly range between 908 and 723 Ma,with εHf(t)>0.Therefore,we classify Meigou granodiorite as island arc granite with adakitic geochemical features.It was generated by interaction between mantle wedge and melt produced by partial melting of the subducted basaltic slab of the Paleo-Qinling Ocean.The Tongyu VHMS deposit was formed in the island arc tectonic setting during Ordovician-Silurian between 439.3±3 Ma and 472±11 Ma.The volcanic exhalation-sedimentation,which was contemporaneous with the submarine volcanics,produced the primary mineralization of the Tongyu Cu deposit.Afterward,the ore bodies and host rocks were reworked and overprinted intensively by structures corresponding with the overall collisional orogenic process of the Qinling Orogenic Belt during the Indosinian period.In contrast to classic VHMS deposits such as the Kuroko deposit in Japan,the Tongyu Cu deposit possesses the dual characteristics of island arc volcanic exhalation and sedimentation as well as structural reworking and overprinting.Therefore,the Tongyu VHMS Cu deposit is a volcanic exhalation and sedimentation-structural reworking and overprinting type deposit. | Ben Lee LaiMin Zhu GuoWei Zhang Bo Guo HuJun Gong AnPing Yao | 2010 | Science China Earth Sciences2010，53，10： | 5 |
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