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Late-Silurian intraplate basalts from the southwestern margin of the Ordos Basin:Implication for decompression melting of metasomatized evolved mantle in extension setting
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作者 Dongxu Wang Hujun Gong +1 位作者 Jiangfeng Qin Fenhong Luo 《Acta Geochimica》 2025年第2期260-277,共18页
The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is o... The Longshan orogenic belt is located in the southwestern margin of Ordos Basin at the junction zone between the Western Qinling and Northern Qilian orogenic belt.Voluminous Early Paleozoic magmatism in this area is of key significance for determining the Early Paleozoic tectonic evolution and deep crust-mantle structure.Previous studies mainly focused on the Paleozoic granites;the coeval mafic rocks in this area are still poorly understood.A set of Late Silurian intraplate tholeiitic basalts has been discovered in Longshan area,providing key evidence for the mantle source and deep geodynamic background in this area.The Late Silurian Angou basalt has similar geochemical features as intraplate tholeiitic basalt,with high Na_(2)O/K_(2)O ratios(5.22-8.25),enriched in large ion lithophile elements and LREE.In combination with their relatively evolved Sr-Nd isotopic composition[^(87)Sr/^(86)Sr(i)=0.7128-0.7140;ε_(Nd)(t)=-5.55 to-3.40],it is suggested that it originated from decompression melting of metasomatized enriched mantle in extensional setting.These results indicate that the mantle source in the junction zone of the West Qinling-North Qilian orogenic belt evolved from depleted to enriched with the continuation of Proto-Tethys subduction from the Cambrian to the Silurian.These results are of great significance to understanding the genesis of contemporaneous granite and the crust-mantle interaction in the junction zone between the Western Qinling and Northern Qilian orogenic belt. 展开更多
关键词 Ordos basin Late Silurian Intraplate basalts Metasomatized enriched mantle extensional setting
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The 144–140 Ma Mafic Dykes in North China and Northeast China Indicating Regional Extensional Tectonic Setting 被引量:1
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作者 XU Huan LIU Yongqing +1 位作者 KUANG Hongwei PENG Nan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期353-354,共2页
Objective Previous studies indicate that the North China Craton(NCC)had undergone the loss of thickened lithosphere and fundamental change of physical and chemical property of lithospheric mantle(the destruction of... Objective Previous studies indicate that the North China Craton(NCC)had undergone the loss of thickened lithosphere and fundamental change of physical and chemical property of lithospheric mantle(the destruction of NCC)during the Mesozoic.The peak period of the destruction of NCC is estimated to be 130 Ma,accompanied by widespread metamorphic core complex,rift basins,A-type granites and mafic dykes. However, it remains greatly controversial on the tectonic setting of NCC in the pre- 130Ma. 展开更多
关键词 NCC Ma Mafic Dykes in North China and Northeast China Indicating Regional extensional Tectonic setting The 144 SHRIMP
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Extensional Setting of Hainan Island in Mesoproterozoic:Evidence from Granitic Intrusions in the Baoban Group
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作者 LIU Yuheng MAO Jingwen +3 位作者 QIU Kunfeng HU Jun WANG Lei XU Deming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第4期1199-1212,共14页
The Mesoproterozoic Baoban Group is the oldest basement in Hainan Island and has played an important role in Columbia(Nuna)supercontinent reconstructions.The Mesoproterozoic granitic intrusions in the Baoban Group are... The Mesoproterozoic Baoban Group is the oldest basement in Hainan Island and has played an important role in Columbia(Nuna)supercontinent reconstructions.The Mesoproterozoic granitic intrusions in the Baoban Group are the most widely-exposed Precambrian magmatic rocks and are the key to understanding the tectonic settings of Hainan Island and its relationship with the South China Block and the Columbia supercontinent.New LA-ICP-MS zircon U-Pb dating on three mylonitic granite samples from the Tuwaishan and Baoban areas yield ages ranging from 1447 Ma to 1437 Ma,representing the absolute timing of the emplacement of the granitic intrusions.Combined with previously published geochronological data for rocks from the Baoban Group and regional mafic intrusions,it is concluded that the Baoban Group formed at 1460-1430 Ma,coeval with the emplacement of the granitic and mafic intrusions.New in-situ zircon LuHf isotope analyses for the three mylonitic granite samples yielded positiveε(t)values,ranging from+0.49 to+8.27,with model ages(T~C)ranging from 2181 Ma to 1687 Ma,suggesting that the granitic intrusions originated from a mixed source of Paleoproterozoic crust with juvenile crust.New zircon trace element data show characteristics of high Th/U values of 0.24-1.50,steep slopes from LREE to HREE and negative Pr,Eu anomalies with positive Ce,Sm anomalies,representing typical magmatic zircons formed in continental crust.Compared with available magmatic and detrital zircon ages from Precambrian rocks in the Cathaysia Block,Yangtze Block and western Laurentia,it is inferred that Hainan Island was separated from both the Cathaysia Block and the Yangtze Block,instead being connected with western Laurentia in the Columbia supercontinent.Considering the decreasing tendency of basin deposition time along the western margin of Laurentia,it is proposed that Hainan Island was located to the north or northwest of the Belt-Purcell Supergroup,along the western margin of Laurentia,during the breakup of the Columbia supercontinent. 展开更多
关键词 zircon U-Pb dating Lu-Hf isotopes granitic intrusions Baoban Group extensional setting Hainan Island
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ROLE OF POST-OROGENICEXTENSIONAL TECTONICS IN THE SUPERGIANT ANTIMONY MINERALIZATION IN CENTRAL HUNAN PROVINCE, SOUTH CHINA
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作者 Yi Jianbin Shan Yehua (Changsha Institute of Geotectonics,Academia Sinica, Changsha, 410013, China) 《Geotectonica et Metallogenia》 1995年第Z1期62-70,共9页
The Xikuangshan antimony deposit in central Hunan, South China, is the largest antimony deposit ever known in the world. The ore bodies are strictly confined to the footwalls of mafor high-angle normal faults which tr... The Xikuangshan antimony deposit in central Hunan, South China, is the largest antimony deposit ever known in the world. The ore bodies are strictly confined to the footwalls of mafor high-angle normal faults which transect the inclined folds in the flank;away from the fault planes,both the homogenization temperatures of inclusions in gangue minerals and the intensity of antimony mineralization decrease.These characteristics strongly demonstrate that the faults are used as the conduit for the metal-bearing fluid in mineralization.The normal faults,striking the NE to NNE,are interpreted to be generated by the postmgenic extension in the time from Cretaceous to Paleogene.Crustal or lithospheric thinning, directly resulting from regional extension inevitably increase the geothermal gradient, Which is likely to cause large-scale convection of underground water that may leach out and transport valuablemetals such as Sb from source rocks.Focussed discharge along the fault zones contributes to the formation of the supergiant antimony deposit in Xikuangshan under the appropriate sedimentary barrier. 展开更多
关键词 post-orogenic extension supergiant ANTIMONY MINERALIZATION central HUNAN SOUTH China
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A fault diagnosis model based on weighted extension neural network for turbo-generator sets on small samples with noise 被引量:12
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作者 Tichun WANG Jiayun WANG +1 位作者 Yong WU Xin SHENG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第10期2757-2769,共13页
In data-driven fault diagnosis for turbo-generator sets,the fault samples are usually expensive to obtain,and inevitably with noise,which will both lead to an unsatisfying identification performance of diagnosis model... In data-driven fault diagnosis for turbo-generator sets,the fault samples are usually expensive to obtain,and inevitably with noise,which will both lead to an unsatisfying identification performance of diagnosis models.To address these issues,this paper proposes a fault diagnosis model for turbo-generator sets based on Weighted Extension Neural Network(W-ENN).WENN is a novel neural network which has three types of connection weights and an improved correlation function.The performance of the proposed model is validated against Extension Neural Network(ENN),Support Vector Machine(SVM),Relevance Vector Machine(RVM)and Extreme Learning Machine(ELM)based models.The results indicate that,on noisy small sample sets,the proposed model is superior to the other models in terms of higher identification accuracy with fewer samples and strong noise-tolerant ability.The findings of this study may serve as a powerful fault diagnosis model for turbo-generator sets on noisy small sample sets. 展开更多
关键词 Fault diagnosis Samples with noise Small samples learning Turbo-generator sets Weighted extension Neural Network
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Tectonic and Geodynamic Setting of Oil and Gas Basins in China
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作者 Chen Fajing Wang Xinwen Zhang Guangya Cao Shoulian Luo ChuanrongDepartment of Geology and Energy Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 1995年第2期30-37,共8页
About 26 sedimentary basins bearing oil and gas are developed in China. They can be classified into two main types . extensional basins and foreland basins . The former are chiefly distributed in the eastern part and ... About 26 sedimentary basins bearing oil and gas are developed in China. They can be classified into two main types . extensional basins and foreland basins . The former are chiefly distributed in the eastern part and the latter in the central and northwestern parts of the country . The present paper discusses the structural characteristics of these basins . including subsidence history , thermal history and structural style and kinematics . Combined with tectonic setting analysis of geophysical data and eruptive rocks , the geodynamic setting of the basins is established , and the formation mechanism of the basins is deduced to have been related to the subduction of the Izanagi and west Pacific plates and the closing of the Tethys ocean . 展开更多
关键词 extensional basin foreland basin geodynamic setting .
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Tectonic Setting of the Cu-Ni Sulfide-Bearing Mafic-Ultramafic Complexes in Northern Jilin Province, NE China
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作者 Dacheng Jia Shen Liu +6 位作者 Hong Zhong Guangying Feng Youqiang Qi Wen Gao Xiao Zhang Tao Jiang Yongxin Mao 《International Journal of Geosciences》 2013年第2期317-328,共12页
There are series of Cu-Ni sulfide-bearing mafic-ultramafic intrusions widespread in north JilinProvince,Northeastern China. The intrusions formed in Xing’an-Mongolian Orogenic Belt near to the northeastern margin of ... There are series of Cu-Ni sulfide-bearing mafic-ultramafic intrusions widespread in north JilinProvince,Northeastern China. The intrusions formed in Xing’an-Mongolian Orogenic Belt near to the northeastern margin of North China Craton. The complexes were formed in almost same period according to the zircon U-Pb dating reported recently, which means that the complexes were formed in same tectonic period and belong to one tectonic magmatic event. The rock assemblages are different from the ophiolite type and Yidun type in orogenic belt. The mafic-ultramafic complexes formed in the range from 217 Ma to 232 Ma coeval with A-type granites in the area, which formed bimodal igneous rock assemblage. According to the regional angular unconformities, there were existed the orogenies of Caledonian, Hercynian, Early Indosinian, Late Indosinian and Yanshanian. The Early Indosinian coeval with orogenic I-type granites and sanukitie that suggesting the lithosphere thickening in the extrusion tectonic setting of orogenic processes, however the Late Indosinian coeval with bimodal igneous rock assemblage that suggesting the lithosphere thinning in the extension tectonic setting of post-orogenic processes in the Xing’an-Mongolian Orogenic Belt. Chemical composition of the mafic-ultramafic rocks has the characteristics of high-Mg and low-K tholeiites related with inter-continental post-orogenic tectonic setting. The trace elements indicate their formed in conditions of continental extension belt or initial rift and has the characteristics of revolution from oceanic island arc, volcanic arc of continental margin to continental extended belt. The low initial Sr isotopic ratios and positive εNd(t) values suggest that the initial magma of the complexes come from the parting melting of depleted lithospheric mantle. The depleted ithospheric mantle was new formed supported by zircon Hf isotope in Hongqiling complex. The depleted lithospheric mantle may be caused by the asthenosheric mantle upwelling and underplating in the tectonic setting of extension during the Late Indosinian post-orogenic processes. 展开更多
关键词 Mafic-Ultramafic INTRUSIONS TECTONIC setting post-orogenic Processes LITHOSPHERIC extension
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Multilayer Multidi mensional Extension Set Theory
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作者 曹少中 杨国为 涂序彦 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期172-176,共5页
In brder to study the contradiction problem of multilayer multidimensional complex systems, the concepts of extension field and stable field of intersection and union of multilayer multidimensional extension set are g... In brder to study the contradiction problem of multilayer multidimensional complex systems, the concepts of extension field and stable field of intersection and union of multilayer multidimensional extension set are given. Then the related operations and properties are discussed. The results of study expand the concepts of intersection and union of extension set to a general situation, and provide the theoretical basis for production of the concepts of intersection and union of multilayer multidimensional matter element system extension set. In this way, it will be possible that matter element system theory is used to creative designs of complex systems. 展开更多
关键词 multilayer multidimensional extension set extension field stable field
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Extension Error Set Based on Extension Set
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作者 Qixin Ye Jinge Zhou 《Applied Mathematics》 2013年第12期1669-1672,共4页
This paper gives the concepts of extension error set and fuzzy extension error set, discusses diverse extension error set and fuzzy extension error set based on extension set and error set, and puts forward the releva... This paper gives the concepts of extension error set and fuzzy extension error set, discusses diverse extension error set and fuzzy extension error set based on extension set and error set, and puts forward the relevant propositions and operations. Finally, it provides proofs of the soundness and completeness for the propositions and operations. 展开更多
关键词 extension set ERROR set FUZZY extension ERROR set
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World Records for Extension Well Set in Eastern South China Sea
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《China Oil & Gas》 CAS 1997年第3期167-167,共1页
关键词 World Records for extension Well set in Eastern South China Sea
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内蒙古四子王旗地区敦德乌苏辉长闪长岩-闪长岩及其地质意义——来自LA-ICP-MS年代学、地球化学的约束 被引量:1
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作者 张明洋 龙舟 +4 位作者 来林 孙广义 周长红 张学斌 韩荣文 《矿产勘查》 2025年第3期437-452,共16页
为研究内蒙古四子王旗敦德乌苏地区基性岩的形成时代和构造环境,本文对该地区出露的闪长岩开展了LA-ICP-MS锆石U-Pb年代学、岩石学、岩石地球化学研究。内蒙古四子王旗敦德乌苏地区出露辉长闪长岩、闪长岩、石英闪长岩和石英二长岩等。... 为研究内蒙古四子王旗敦德乌苏地区基性岩的形成时代和构造环境,本文对该地区出露的闪长岩开展了LA-ICP-MS锆石U-Pb年代学、岩石学、岩石地球化学研究。内蒙古四子王旗敦德乌苏地区出露辉长闪长岩、闪长岩、石英闪长岩和石英二长岩等。闪长岩的LA-ICP-MS锆石U-Pb测年结果为(261.7±2.4)Ma,时代为中二叠世。岩石SiO_(2)含量为48.89%~66.86%,Al_(2)O_(3)含量为14.80%~18.22%,全碱含量较高:Na_(2)O+K_(2)O为5.93%~9.00%,MgO含量为1.01%~6.25%,Mg#为36~61,TiO_(2)=0.68%~2.67%,平均为1.65%。稀土具轻稀土富集、重稀土较平直的右倾型曲线((La/Yb)_(N)值为14.80~34.12),δEu为弱负Eu异常(0.77~1.05)。Rb、Ba、K、Pb、Sr富集;Nb、Ta、Th相对亏损。整体呈“隆起”状多元素原始地幔标准化配分特征,除Nb、Ta元素相对亏损外,与洋岛玄武岩(OIB)或板内玄武岩的特征相似。高的Zr/Y(4.07~27.54)值显示可能来源于大陆板内富集单元。综合区域地质背景,认为四子王旗敦德乌苏地区中二叠世辉长闪长岩形成于大陆拉张环境,内蒙古中部古亚洲洋可能在晚石炭世之前已经闭合。 展开更多
关键词 辉长闪长岩 年代学 岩石地球化学 中二叠世 板内拉张环境 四子王旗 内蒙古
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THEOREMS OF INTERVAL FUZZY SET AND ITS OPERATION RULES 被引量:3
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作者 吴顺祥 曹达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期136-144,共9页
Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuz... Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuzzy set are studied firstly, and then the cut set of interval fuzzy set is proposed. Moreover, the decomposition theo- rem, the representation theorem and the extension theorem of interval fuzzy set are presented. Finally, examples are given to demonstrate that the classical fuzzy set is a special case of interval fuzzy set and interval fuzzy set is an effective expansion of the classical fuzzy set. 展开更多
关键词 interval fuzzy set decomposition theorem representation theorem extension theorem
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热液锡矿床构造控矿作用
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作者 肖昌浩 邓军 《地质力学学报》 北大核心 2025年第5期898-925,共28页
锡作为支撑信息产业、航空航天及国防科技等战略领域的关键矿产,其资源分布在全球极不均匀。开展全球主要锡矿产区对比研究,对理解锡矿成矿规律及全球锡矿勘查和开采具有重要意义。为了更好地理解不同构造背景下锡矿床形成的构造环境及... 锡作为支撑信息产业、航空航天及国防科技等战略领域的关键矿产,其资源分布在全球极不均匀。开展全球主要锡矿产区对比研究,对理解锡矿成矿规律及全球锡矿勘查和开采具有重要意义。为了更好地理解不同构造背景下锡矿床形成的构造环境及不同类型锡矿床的构造控矿样式,通过系统梳理大陆裂谷和3种汇聚型板块边界典型的锡矿床产出构造环境,并总结了常见锡矿床的构造控矿样式,取得了如下认识:第一,针对热液流体中锡的迁移与锡石沉淀的数值模拟表明,成矿热液未被花岗质围岩完全缓冲是导致锡有效运移和局部富集的关键;这一过程必须依赖高效的构造通道才能实现,从而凸显了构造在热液锡矿成矿中的核心控制作用。第二,无论是在裂谷伸展、安第斯型大陆边缘挤压、西太平洋型大陆边缘弧后伸展以及碰撞造山后伸展哪种构造背景下,热液锡矿床成矿仍符合岩浆热液型锡矿成矿模型的一贯主张,即上述伸展背景下高分异的长英质岩石主导锡成矿作用,伸展/张扭性构造背景有利于热液锡矿床形成。此外,近年部分学者报道了同增生造山过程中变质作用导致锡的预富集,并详细揭示了进变质过程中锡的活化和退变质过程中黑云母绿泥石化释放Sn形成锡石的过程。上述研究为碰撞造山型锡矿成矿理论发展奠定了基础。第三,岩浆热液型锡矿床以矽卡岩型和石英脉型锡矿床为主,通常二者常伴生出现。成锡岩体内部及周缘发育含锡的岩浆冷凝收缩裂隙、水岩分离裂隙、岩浆侵位挤压裂隙和区域构造应力叠加裂隙等。远离成锡岩体受岩石流变学差异或断裂(切层断层和顺层断层)的强烈控制,形成多样的矿化网络结构。根据矿化网络结构内是否发育角砾,可以把含矿脉分为2类。一类是不发育角砾的容矿构造,按复杂程度逐渐增加分为单脉、单脉复合系统、“非”字型脉系统、对称复合脉系统和不对称复合脉系统。单脉的形态及延伸与容矿构造力学性质关系密切。另一类是发育角砾的容矿构造,按复杂程度逐渐增加分为产于剪切带内对称脉、角砾脉系统、脉与顶板网脉复合系统、多角砾脉复合系统。构造序次和构造分异的厘定对热液锡矿床构造控矿作用的研究具有重要作用,加强典型矿床/矿集区构造序次和构造分异的精细填图并结合数值模拟和岩石流变学实验研究是热液锡矿床构造控矿作用研究的发展方向。 展开更多
关键词 热液锡矿床 碰撞造山型锡矿床 大地构造背景 伸展/张扭构造体制 构造控矿样式
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九岭南缘宜丰—奉新锂矿田锂矿成岩成矿地质背景 被引量:1
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作者 周建廷 罗微 +3 位作者 熊燃 肖业斌 张福神 邱文江 《地质科学》 北大核心 2025年第1期229-249,共21页
宜丰—奉新锂矿田是九岭南缘最新探明的世界级花岗岩型锂矿田。为了进一步研究九岭南缘成岩成矿地质背景和稀有金属成矿规律,笔者对与成矿有关的甘坊复式岩体进行了地质特征、地球化学和年代学研究,探讨了甘坊复式岩体侵入期次、构造环... 宜丰—奉新锂矿田是九岭南缘最新探明的世界级花岗岩型锂矿田。为了进一步研究九岭南缘成岩成矿地质背景和稀有金属成矿规律,笔者对与成矿有关的甘坊复式岩体进行了地质特征、地球化学和年代学研究,探讨了甘坊复式岩体侵入期次、构造环境和和岩浆源区。宜丰—奉新地区花岗岩型锂矿可划分为碱性长石花岗岩型和花岗细晶(斑)岩型两种类型。甘坊复式岩体(包括甘坊岩体、古阳寨岩体、武堂岩体和白水洞岩体)为一复式岩套,经历了燕山期早、晚两期4个阶段的岩浆作用。甘坊复式岩体出现4次成岩成矿高峰(期),早白垩世是该矿田锂矿主成矿期。甘坊复式岩体是九岭南缘地区同一岩浆源区经过多次重熔,不同阶段、不同期次侵位,高度分异演化,累积增长形成的。甘坊岩体、古阳寨岩体、武堂岩体和白水洞岩体是岩浆演化不同阶段的产物。成岩成矿作用是统一的热力学与地球化学成矿系统,时代越是往后,花岗岩演化程度越高越彻底,岩浆热液流体参与越明显,成矿作用也越强,成矿规模越大。花岗岩成因类型为S型花岗岩,其岩浆源区主要为成熟度较高的变质泥质岩和砂岩。成岩成矿处于陆内造山同碰撞后伸展构造环境。 展开更多
关键词 花岗岩型锂矿床 成岩成矿时代 伸展构造环境 S型花岗岩 宜丰—奉新锂矿田
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内蒙古七家子早三叠世侵入岩成因及其地质意义
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作者 任颖伟 王红 +2 位作者 董国臣 侯飞飞 梁景利 《现代地质》 北大核心 2025年第5期1232-1248,共17页
古亚洲洋的演化过程一直是地学研究的热点问题,特别是对其闭合时限及闭合后构造演化的研究。本文首次在内蒙古奈曼旗南部地区识别出一套由角闪辉长岩和花岗质岩石组成的基性-酸性杂岩体,通过开展锆石U-Pb定年和地球化学研究,限定其成岩... 古亚洲洋的演化过程一直是地学研究的热点问题,特别是对其闭合时限及闭合后构造演化的研究。本文首次在内蒙古奈曼旗南部地区识别出一套由角闪辉长岩和花岗质岩石组成的基性-酸性杂岩体,通过开展锆石U-Pb定年和地球化学研究,限定其成岩时代,同时探讨其成因联系、岩浆源区及构造背景。锆石U-Pb测年结果表明:角闪辉长岩、中粒二长花岗岩及细粒二长花岗岩的侵位年龄分别为(249.3±1.2)Ma、(247.4±2.8)Ma和(246.2±1.4)Ma,为早三叠世岩浆同时侵入的产物。地球化学数据显示,角闪辉长岩与花岗质岩体的SiO_(2)含量在50.78%~69.81%范围存在明显间断,表现出双峰式岩浆岩特征。角闪辉长岩属准铝质岩石,具有贫碱、高Ti、富Fe的特征,稀土元素总含量较高,Ce和Eu异常不明显(δCe=0.94~0.98,δEu=0.90~1.02);富集大离子亲石元素(Ba、Th、U),而亏损Nb、P、Ti等高场强元素。这些地球化学特征表明角闪辉长岩是由继承俯冲流体交代影响的岩石圈地幔部分熔融,并有部分壳源物质加入形成。花岗质岩体为一套高钾钙碱性,过铝质Ⅰ型花岗岩;具有相似的地球化学组成,均表现出富碱,贫Ca、Mg的特点,以及较高的微量元素含量,强烈Eu负异常和轻微Ce负异常;明显富集Rb、Th、K等大离子亲石元素,亏损Nb、Ta、Sr等高场强元素,均来源于地壳物质部分熔融,并表现出由细粒二长花岗岩向中粒二长花岗岩演化的趋势。结合岩体地球化学特征和区域已有研究资料,认为七家子杂岩体形成于碰撞后伸展环境,古亚洲洋闭合后俯冲板片断离,诱使具有俯冲组分特征的岩石圈地幔部分熔融,部分基性岩浆在上侵过程中受到壳源物质的混染形成角闪辉长岩;另一部分基性岩浆底侵烘烤下地壳,致使壳源物质部分熔融,而后同时侵位形成双峰式岩浆岩。 展开更多
关键词 古亚洲洋 早三叠世 双峰式岩浆岩 碰撞后伸展环境 Ⅰ型花岗岩 内蒙古 奈曼旗
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蒙古-鄂霍茨克造山带南缘晚中生代火山岩地质、地球化学特征及其构造环境
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作者 吴昱诚 李伟 《陕西地质》 2025年第1期39-46,85,共9页
蒙古-鄂霍茨克南缘分布大面积中生代火山岩,呈北东向展布在我国大兴安岭北部及中蒙、中俄邻区。火山岩岩性主要为粗面玄武岩、玄武质粗安岩、粗安岩、粗面岩和流纹岩。本文系统收集火山岩锆石U-Pb和全岩基质Ar-Ar年代学数据,火山岩时代... 蒙古-鄂霍茨克南缘分布大面积中生代火山岩,呈北东向展布在我国大兴安岭北部及中蒙、中俄邻区。火山岩岩性主要为粗面玄武岩、玄武质粗安岩、粗安岩、粗面岩和流纹岩。本文系统收集火山岩锆石U-Pb和全岩基质Ar-Ar年代学数据,火山岩时代主要集中在114.5 Ma-162.4 Ma,为晚侏罗世-早白垩世。通过分析统计32个岩石地球化学数据,认为火山岩表现为碱性-亚碱性过渡性质。另外,Sr-Nd同位素特征显示这些火山岩源于受流体交代的地幔楔或岩石圈地幔。结合区域构造演化特征,认为蒙古-鄂霍茨克南缘中生代火山岩形成于造山后伸展环境。 展开更多
关键词 蒙古-鄂霍茨克造山带 晚中生代火山岩 年代学 地球化学 交代地幔楔 造山后伸展环境
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北山造山带南缘下二叠统双堡塘组火山岩地球化学特征及构造意义
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作者 慕洁 俞胜 《兰州大学学报(自然科学版)》 北大核心 2025年第4期513-522,532,共11页
北山造山带是古亚洲洋构造域一个重要的构造活动带,依据岩相学、岩石地球化学、LAICP-MS锆石U-Pb测年等,探讨北山造山带南缘下二叠统双堡塘组火山岩的形成环境.结果表明,双堡塘组流纹岩形成时代为284.2±0.1 Ma,形成于早二叠世.流... 北山造山带是古亚洲洋构造域一个重要的构造活动带,依据岩相学、岩石地球化学、LAICP-MS锆石U-Pb测年等,探讨北山造山带南缘下二叠统双堡塘组火山岩的形成环境.结果表明,双堡塘组流纹岩形成时代为284.2±0.1 Ma,形成于早二叠世.流纹岩地球化学特征显示其具有高硅(SiO_(2))、高碱(Na_(2)O+K_(2)O)、贫钙(CaO)、贫镁(MgO)的特征,富集大离子亲石元素Rb、Pb、K,强烈亏损高场强元素Ba、Nb、P、Ti.结合区域地质背景,双堡塘组流纹岩岩浆可能来自下地壳部分熔融,在后期演化过程中可能经历了较为强烈的斜长石、磷灰石和钛铁矿等矿物的分离结晶作用.根据相关判别图解并结合区域地质资料分析,双堡塘组流纹岩形成于后碰撞伸展拉张环境,说明北山造山带南缘在早二叠世进入后碰撞演化阶段. 展开更多
关键词 双堡塘组 火山岩 早二叠世 后碰撞伸展阶段
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myPNOZ新模块上市,远不止功能扩展这么简单!
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《智慧工厂》 2025年第2期38-38,共1页
近日,皮尔磁PILZ公司推出了全新的myPNOZ Extension Set,简单来讲就是新推出了多个myPNOZ的模块,新模块引入了多项新功能,进一步提升了产品的灵活性和适用性。更多模块,更多可能myPNOZ Extension Set系列中的每个模块都针对不同的应用... 近日,皮尔磁PILZ公司推出了全新的myPNOZ Extension Set,简单来讲就是新推出了多个myPNOZ的模块,新模块引入了多项新功能,进一步提升了产品的灵活性和适用性。更多模块,更多可能myPNOZ Extension Set系列中的每个模块都针对不同的应用场景进行了优化设计。咱们先走马观花,了解一下新模块的主要功能亮点:PNOZ yi5输入模块:具备四对安全输入端,支持多种安全功能的组合,适用于复杂的工业环境。 展开更多
关键词 PILZ公司 安全输入端 extension set myPNOZ
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Optimizing pipeline for a RISC processor with multimedia extension ISA 被引量:1
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作者 肖志斌 刘鹏 +1 位作者 姚英彪 姚庆栋 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期269-274,共6页
The 32-bit extensible embedded processor RISC3200 originating from an RTL prototype core is intended for low-cost consumer multimedia products. In order to incorporate the reduced instruction set and the multimedia ex... The 32-bit extensible embedded processor RISC3200 originating from an RTL prototype core is intended for low-cost consumer multimedia products. In order to incorporate the reduced instruction set and the multimedia extension instruction set in a unifying pipeline, a scalable super-pipeline technique is adopted. Several other optimization techniques are proposed to boost the frequency and reduce the average CPI of the unifying pipeline. Based on a data flow graph (DFG) with delay information, the critical path of the pipeline stage can be located and shortened. This paper presents a distributed data bypass unit and a centralized pipeline control scheme for achieving lower CPI. Synthesis and simulation showed that the optimization techniques enable RISC3200 to operate at 200 MHz with an average CPI of 1.16. The core was integrated into a media SOC chip taped out in SMIC 0.18-micron technology. Preliminary testing result showed that the processor works well as we expected. 展开更多
关键词 PIPELINE RISC Single-instruction-multiple-data (SIMD) Instruction set architecture (ISA) Multimedia extension
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Power Quality Assessment Based on Rough AHP and Extension Analysis 被引量:1
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作者 Guofeng Liu Can Zhang +1 位作者 Zhengyi Zhu Xuyan Wang 《Energy Engineering》 EI 2022年第3期929-946,共18页
Due to the increasing power consumption of whole society and widely using of new non-linear and asymmetric electrical equipment,power quality assessment problem in the new period has attracted more and more attention.... Due to the increasing power consumption of whole society and widely using of new non-linear and asymmetric electrical equipment,power quality assessment problem in the new period has attracted more and more attention.The mathematical essence of comprehensive assessment of power quality is a multiattribute optimal decision-making problem.In order to solve the key problem of determining the indicator weight in the process of power quality assessment,a rough analytic hierarchy process(AHP)is proposed to aggregate the judgment opinions of multiple experts and eliminate the subjective effects of single expert judgment.Based on the advantage of extension analysis for solving the incompatibility problem,extension analysis method is adopted to assess the power quality.The assessment grades of both total power quality and each assessment indicator are obtained by correlation function.Through a case of 110 kV bus of a converting station in a wind farm of China,the feasibility and effectiveness of the propose method are demonstrated.The result shows that the proposed method can determine the overall power quality of power grid,as well as compare the differences among the performance of assessment indicators and provide the basis for further improving of power quality. 展开更多
关键词 Power quality comprehensive assessment decision making rough sets analytic hierarchy process extension analysis
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