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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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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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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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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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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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吉林红旗岭晚三叠世镁铁超镁铁质侵入体矿物化学和岩石地球化学特征:对镍铜成矿的启示
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作者 王建 杨言辰 +1 位作者 李爱 袁海齐 《地学前缘》 EI CAS CSCD 北大核心 2024年第2期249-269,共21页
吉林红旗岭镁铁超镁铁质侵入岩群位于中亚造山带东段南缘,由3个北西向岩带(I、II、III)组成,包括30多个小岩株,其中I-岩带的部分岩体伴有铜镍矿化,并且其1和7号岩体分别形成了中型和大型岩浆铜镍硫化物型矿床。矿床主要容矿岩石为辉橄... 吉林红旗岭镁铁超镁铁质侵入岩群位于中亚造山带东段南缘,由3个北西向岩带(I、II、III)组成,包括30多个小岩株,其中I-岩带的部分岩体伴有铜镍矿化,并且其1和7号岩体分别形成了中型和大型岩浆铜镍硫化物型矿床。矿床主要容矿岩石为辉橄岩、橄辉岩、斜方辉石岩、二辉石岩、苏长岩和辉长岩。主量元素方面,红旗岭岩群具有富镁(w(MgO)=20.7%~31.1%)、低钛(w(TiO_(2))=0.33%~0.79%)、低碱(w(K 2 O+Na 2 O)=0.60%~2.29%)和硅(w(SiO_(2))=40.0%~53.0%)变化范围大的特征;微量元素方面,红旗岭岩群呈现弱富集LREE和LILE(Th)以及亏损HREE和HFSE(Nb-Ta-Ti)。岩相学、地球化学和矿物(橄榄石、斜方辉石、单斜辉石、尖晶石、斜长石和角闪石)主微量元素特征表明,红旗岭岩群明显不同于洋岛型玄武岩、阿拉斯加型环状杂岩和科马提岩,但与岛弧玄武岩以及中亚造山带西段的“黄山西”和“黄山东”铜镍硫化物矿床的容矿超镁铁质岩相似,其母岩浆是一种富Mg、亏损Nb-Ta的岛弧拉斑玄武质熔体,形成于晚三叠世古亚洲洋闭合后伸展环境,演化过程中经历了地壳混染和分离结晶作用,含矿母岩浆可能经历了硫化物的“二次熔离”,最终形成了铂族元素(PGE)亏损型岩浆铜镍硫化物矿床。 展开更多
关键词 岩浆铜镍硫化物矿床 高镁拉斑玄武质母岩浆 硫化物熔离 铂族元素亏损 碰撞后伸展环境 红旗岭 中亚造山带
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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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闽北邵武地区玄武安山岩的成因和意义——来自年代学、地球化学及Nd-Hf同位素的约束
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作者 周伏顺 林鑫 +1 位作者 王郅睿 邵程波 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第3期840-861,共22页
东南沿海地区中生代火山岩研究成果颇丰,但有关中侏罗世晚期基性火山岩的报道较少,限制了对该区域中生代构造-岩浆活动及大地构造演化的深入理解。本文对江绍断裂带东南侧邵武地区的中生代火山岩开展了系统的岩石学、锆石U-Pb年代学、锆... 东南沿海地区中生代火山岩研究成果颇丰,但有关中侏罗世晚期基性火山岩的报道较少,限制了对该区域中生代构造-岩浆活动及大地构造演化的深入理解。本文对江绍断裂带东南侧邵武地区的中生代火山岩开展了系统的岩石学、锆石U-Pb年代学、锆石Lu-Hf同位素、地球化学和Sm-Nd同位素研究。结果显示:邵武地区玄武安山岩喷发年龄为(161.0±2.0)Ma;同位素地球化学结果显示,这些样品中—晚侏罗世锆石的ε_(Hf)(t)值介于-14.33~-10.41之间,ε_(Nd)(t)值较低(-9.2~-8.4),反映富集Nd同位素的特征;岩石地球化学结果表明,该套火山岩具有高w(Al_(2)O_(3))、w(Na_(2)O)、低w(MgO)、w(TFe_(2)O_(3))等特征,稀土总量较低,稀土配分曲线为右倾型,且具弱的Eu负异常,大离子亲石元素Rb、Ba和K相对富集,高场强元素Nb、Ta、Ti、P等相对亏损。综合岩石学和地球化学研究结果,本文认为邵武玄武安山岩起源于交代岩石圈地幔的部分熔融,并经历一定结晶的分异作用,其大地构造背景总体为板内环境。结合前人对区域构造-岩浆活动的认识,本文认为在中侏罗世晚期,太平洋俯冲板片发生回撤、撕裂,导致幔源岩浆底侵并置换了古老壳源岩石,从而东南沿海地区虽整体处于挤压背景,但仍存在局部拉张环境。 展开更多
关键词 中侏罗世 地球化学 伸展背景 玄武安山岩 东南沿海
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Multi-isotope and geochemical approach to the magma source and tectonic setting of Proterozoic anorthosite massifs and AnorthositeMangerite-Charnockite-Granite(AMCG)suites
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作者 L.A.Elizondo-Pacheco L.A.Solari +4 位作者 R.González-Guzmán H.L.He E.Becerra-Torres J.A.Ramírez-Fernández R.Maldonado 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第6期2-21,共20页
The occurrence of massif-type anorthosite intrusions is a widespread Proterozoic phenomenon.They are usually associated with gabbroic,charnockitic,and granitic rocks,comprising the so-called anorthositemangerite-charn... The occurrence of massif-type anorthosite intrusions is a widespread Proterozoic phenomenon.They are usually associated with gabbroic,charnockitic,and granitic rocks,comprising the so-called anorthositemangerite-charnockite-granite(AMCG)suite.Although these rocks have been extensively studied worldwide,several aspects concerning their formation remain unsettled.Among them,the magma source and the tectonic setting are the most important.To evaluate these issues,we first compiled geochemical and isotopic data of Proterozoic anorthosite massifs and AMCG suites worldwide and stored it in a database named datAMCG.This plethora of data allows us to make some important interpretations.We argue that the wide-ranging multi-isotopic composition of this group of rocks reflects varying proportions of juvenile mantle-derived melts and crustal components.We interpret that the precursor magmas of most massive anorthosite bodies and associated mafic rocks have a mantle-dominated origin.However,we highlight that a crustal component is indispensable to generate these lithologies.Adding variable amounts of this material during succeeding multi-stage assimilation-fractional crystallization(AFC)processes gives these intrusions their typical mantle-crustal hybrid isotopic traits.In contrast,a crustaldominant origin with a complementary mantle component is interpreted for most MCG rocks.In summary,the isotopic information in datAMCG indicates that both sources are necessary to generate AMCG rocks.Therefore,we suggest that hybridized magmas with different mantle-crust proportions originate these rocks.This interpretation might offer a more nuanced and accurate depiction of this phenomenon in future work instead of choosing a single-sourced model as in the past decades.Finally,tectonomagmatic diagrams suggest that the rocks under study were likely generated in a tectonic environment that transitioned between collision and post-collisional extension,sometimes involving subduction-modified mantle sources.This interpretation is supported by geological and geochronological information from most complexes,thus challenging the Andean-type margins as an ideal tectonic setting. 展开更多
关键词 Massif-type anorthosite Anorthosite-granite suite Magmatic sources Hybridized magmas Tectonic setting Post-orogenic extension
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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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New approach to develop a 3D non-isothermal computational framework for injection molding process based on level set method 被引量:2
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作者 Xin Zhuang Jie Ouyang +1 位作者 Chuntao Jiang Qingsheng Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第7期832-842,共11页
The simulation of three-dimensional (3D) non-isothermal, non-Newtonian fluid filling process is an extremely difficult task and remains a challenging problem, which includes polymer melt flow with free surface coupl... The simulation of three-dimensional (3D) non-isothermal, non-Newtonian fluid filling process is an extremely difficult task and remains a challenging problem, which includes polymer melt flow with free surface coupled with transient heat transfer. This paper presents a full 3D non-isothermal two-phase flow model to predict the complex flow in melt filling process, where the Cross-WLF model is applied to characterize the rheological behav- ior of polymer melt. The governing equations are solved using finite volume method with SIMPLEC algorithm on collocated grids and the melt front is accurately captured by a high resolution level set method. A domain exten- sion technique is adopted to deal with the complex cavities, which greatly reduces the computational burden. To verify the validity of the developed 3D approach, the melts filling processes in two thin rectangular cavities (one of them with a cylindrical insert) are simulated. The predicted melt front interfaces are in good agreement with the experiment and commercial software prediction. For a case with a rather complex cavity, the dynamic filling process in a hemispherical shell is successfully simulated. All of the numerical results show that the developed numerical procedure can provide a reasonable orediction for injection molding process. 展开更多
关键词 Injection moldingNon-isothermalFinite voIume/SIMPLEC methodDomain extension techniqueHigh resolution level set method
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伊犁地块北缘早石炭世阿拉斯坦闪长岩成因及其对北天山洋俯冲过程的启示 被引量:3
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作者 王盟 裴先治 +4 位作者 张进江 陈有炘 赵少伟 张波 曹明 《地质通报》 CAS CSCD 北大核心 2023年第5期771-787,共17页
伊犁地块北缘存在大量石炭纪岩浆岩,但对早石炭世中晚期(340~320 Ma)的岩浆岩鲜有报道,在一定程度上影响对该阶段区域构造演化的认识。为探讨伊伊犁地块北缘早石炭世的大地构造背景,对伊犁地块北缘阿拉斯坦河流域新发现的早石炭世中期... 伊犁地块北缘存在大量石炭纪岩浆岩,但对早石炭世中晚期(340~320 Ma)的岩浆岩鲜有报道,在一定程度上影响对该阶段区域构造演化的认识。为探讨伊伊犁地块北缘早石炭世的大地构造背景,对伊犁地块北缘阿拉斯坦河流域新发现的早石炭世中期闪长岩体开展了详细的岩石学、地球化学、锆石U-Pb年代学和Lu-Hf同位素研究。阿拉斯坦闪长岩岩体中发育微粒闪长质包体,两者在多组主量和微量元素的双变量图解中均表现出不同的演化趋势,表明其不同的成因和起源。两种岩石均具有富集大离子亲石元素,而亏损Nb、Ta、Ti等高场强元素的特征,具有俯冲带岩石的地球化学信息。结合区域资料,认为伊犁地块北缘在早石炭世中晚期之后整体处于伸展背景,可能与北天山洋的俯冲板片回转或后撤相关。 展开更多
关键词 早石炭世 伊犁地块 闪长岩 伸展背景 新疆
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Analysis of Extension Categorical Data Mining Process for the Extension Interior Designing
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作者 Hui Ma Guangtian Zou 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第6期26-31,共6页
On the basis of extension architectonics,this paper researches the process of extension categorical data mining for extension interior design. In accordance with the theory of extension data mining,the extension categ... On the basis of extension architectonics,this paper researches the process of extension categorical data mining for extension interior design. In accordance with the theory of extension data mining,the extension categorical data mining for the extension interior design can be divided into data preparation,the operation of mining and knowledge application. The paper expatiates the main content and cohesive relations of each link,and emphatically discusses extension acquisition,analysis extension,categorical mining extension,knowledge application extension and other several core nodes that are related with data. Through the knowledge fusion of extension architectonics and data mining,the paper discusses the process of knowledge requirements with multiple classification under different mining targets. The purpose of this paper is to explore a whole categorical data mining process of interior design from extension design data to the design of knowledge discovery and extension application. 展开更多
关键词 extension categorical data mining extension sets extension interior design
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Comparison of Classical Method, Extension Principle and α-Cuts and Interval Arithmetic Method in Solving System of Fuzzy Linear Equations
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作者 Sahidul Islam Md. Saiduzzaman +1 位作者 Md. Shafiqul Islam Abeda Sultana 《American Journal of Computational Mathematics》 2019年第1期1-24,共24页
The system of linear equations plays a vital role in real life problems such as optimization, economics, and engineering. The parameters of the system of linear equations are modeled by taking the experimental or obse... The system of linear equations plays a vital role in real life problems such as optimization, economics, and engineering. The parameters of the system of linear equations are modeled by taking the experimental or observation data. So the parameters of the system actually contain uncertainty rather than the crisp one. The uncertainties may be considered in term of interval or fuzzy numbers. In this paper, a detailed study of three solution techniques namely Classical Method, Extension Principle method and α-cuts and interval Arithmetic Method to solve the system of fuzzy linear equations has been done. Appropriate applications are given to illustrate each technique. Then we discuss the comparison of the different methods numerically and graphically. 展开更多
关键词 Fuzzy set CLASSICAL Solution extension Principle α-Cut and INTERVAL ARITHMETIC METHOD
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苏丹红海州新元古代A型花岗岩的地球化学特征及构造意义 被引量:2
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作者 周佐民 李勇 +1 位作者 刘晓阳 吴兴源 《华北地质》 2023年第1期71-79,86,共10页
苏丹红海州位于努比亚地盾,本文在该地厘定出一套新元古代花岗岩,由中粗粒-中细粒正长花岗岩、中细粒碱长花岗岩组成,LA-ICP-MS定年结果显示,岩体形成于713±4Ma,属于泛非造山事件的产物。花岗岩SiO_(2)含量较高,为70.80%~77.83%,A/... 苏丹红海州位于努比亚地盾,本文在该地厘定出一套新元古代花岗岩,由中粗粒-中细粒正长花岗岩、中细粒碱长花岗岩组成,LA-ICP-MS定年结果显示,岩体形成于713±4Ma,属于泛非造山事件的产物。花岗岩SiO_(2)含量较高,为70.80%~77.83%,A/CNK为0.94~1.08,A/NK为1.12~1.44,为准铝质-弱过铝质花岗岩。花岗岩具有相似的稀土元素和微量元素配分模式,稀土配分模式呈右倾V字形曲线,轻重稀土分异中等(LREE/HREE=2.46~7.13),δEu为0.30~0.57,负铕异常中等-强烈。富含大离子亲石元素Th、U、K和高场强元素Zr、Hf,亏损高场强元素Nb、Ta、Sr、P和Ti。花岗岩具有低I_(Sr)比值、亏损ε_(Nd)(t)值和ε_(Hf)(t)值,T_(DM1)与T_(DM2)值较为一致。岩体为A_(2)型花岗岩,形成于俯冲阶段弧后拉张环境,因弧后伸展减薄导致软流圈物质上涌,明显的升温、减压促使新生地壳部分熔融。 展开更多
关键词 苏丹红海州 努比亚地盾 新元古代 A型花岗岩 新生地壳 弧后拉张
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桂东南云开地区南渡钾玄质侵入岩的年代学、地球化学及其地质意义
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作者 周鹏程 秦亚 +4 位作者 杨启军 马强分 林炫名 钟宁军 邓伟强 《桂林理工大学学报》 CAS 北大核心 2023年第4期535-546,共12页
为约束桂东南地区燕山早期的构造环境,对南渡杂岩体开展岩相学、岩石地球化学和LA-ICP-MS锆石U-Pb年代学研究。南渡杂岩体由谭福、六廪、新村和石河4个岩性单元构成,主要岩石类型为石英二长岩、二长闪长岩、正长岩、石英二长斑岩、角闪... 为约束桂东南地区燕山早期的构造环境,对南渡杂岩体开展岩相学、岩石地球化学和LA-ICP-MS锆石U-Pb年代学研究。南渡杂岩体由谭福、六廪、新村和石河4个岩性单元构成,主要岩石类型为石英二长岩、二长闪长岩、正长岩、石英二长斑岩、角闪正长斑岩等。2件样品的LA-ICP-MS锆石U-Pb年龄分别为155.2±1.7 Ma和155.9±1.8 Ma,表明南渡杂岩体形成于燕山早期的晚侏罗世。南渡杂岩体的常量元素具有高硅铝、低铁镁和富碱的特征;里特曼指数为3.56~6.77,全碱(Alk)含量6.33%~11.59%,K_(2)O/Na_(2)O值为1.02~1.63。南渡杂岩体呈现轻稀土富集的右倾型球粒陨石标准化配分模式,轻微负Eu异常;富集大离子亲石元素、Zr和Hf,中等Sr、P和Ti亏损,无明显Nb、Ta异常。在Harker图解上,TiO_(2)、^(T)Fe_(2)O_(3)、MgO、CaO、MnO和P_(2)O_(5)均与SiO_(2)呈良好的负相关性,而Al_(2)O_(3)和Na_(2)O与SiO_(2)无明显相关关系;结合Sr、P和Ti的亏损,以及无负Eu异常的特征,暗示可能存在磷灰石、钛铁矿和单斜辉石的分离结晶作用,而无斜长石的分离结晶作用。南渡杂岩体的岩相学和岩石地球化学特征表明,其为典型的板内钾玄质岩石,形成于板内伸展构造环境,可能与华南大陆内部燕山早期的软流圈地幔物质上涌,岩石圈伸展和裂谷作用有关。 展开更多
关键词 LA-ICP-MS锆石定年 钾玄质侵入岩 伸展构造环境 南渡杂岩体 桂东南
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Partial Groups, Simplicial K(G, 1)’s and Kan Complexes
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作者 Solomon Jekel 《Advances in Pure Mathematics》 2023年第11期725-731,共7页
In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the... In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the sub-complex realizes as a K(G, 1). This type of sub-complex appears naturally in several topological and algebraic contexts. In this note we prove that regularity of a partial group implies that the Kan extension condition is satisfied on its nerve in dimensions greater than one, and in dimension one a weaker version of the extension condition holds. 展开更多
关键词 Partial Group Simplicial set NERVE Kan extension
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