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Deformations and extensions of modified λ-differential Lie-Yamaguti algebras
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作者 TENG Wen PAN Yuewei 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第4期115-127,共13页
The modifiedλ-differential Lie-Yamaguti algebras are considered,in which a modifiedλ-differential Lie-Yamaguti algebra consisting of a Lie-Yamaguti algebra and a modifiedλ-differential operator.First we introduce t... The modifiedλ-differential Lie-Yamaguti algebras are considered,in which a modifiedλ-differential Lie-Yamaguti algebra consisting of a Lie-Yamaguti algebra and a modifiedλ-differential operator.First we introduce the representation of modifiedλ-differential Lie-Yamaguti algebras.Furthermore,we establish the cohomology of a modifiedλ-differential Lie-Yamaguti algebra with coefficients in a representation.Finally,we investigate the one-parameter formal deformations and Abelian extensions of modifiedλ-differential Lie-Yamaguti algebras using the second cohomology group. 展开更多
关键词 Lie-Yamaguti algebra modifiedλ-differential operator representation and cohomology one-parameter formal deformation Abelian extension
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Energy dissipation characteristics of sandstone under triaxial extension with different confining pressures
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作者 MA Chun-de TAN Guan-shuang +2 位作者 YANG Wen-yuan KANG Zi-hao ZHANG Gui-yin 《Journal of Central South University》 2025年第6期2195-2207,共13页
After excavation,some of the surrounding rock mass is in a state of triaxial extension,exhibiting tensile or shear fracture modes.To study the energy mechanism of tensile fracture turning to shear fracture,a series of... After excavation,some of the surrounding rock mass is in a state of triaxial extension,exhibiting tensile or shear fracture modes.To study the energy mechanism of tensile fracture turning to shear fracture,a series of triaxial extension tests were conducted on sandstone under confining pressures of 10,30,50 and 70 MPa.Elastic energy and dissipated energy were separated by single unloading,the input energy u_(t),elastic energy u_(e),and dissipated energy u_(d)at different unloading stress levels were calculated by the integrating stress−strain curves.The results show that tensile cracks dominate fracture under lower confining pressure(10 MPa),and shear cracks play an increasingly important role in fracture as confining pressure increases(30,50 and 70 MPa).Based on the phenomenon that u_(e)and u_(d)increase linearly with increasing u_(t),a possible energy distribution mechanism of fracture mode transition under triaxial extension was proposed.In addition,it was found that peak energy storage capacity is more sensitive to confining pressure compared to elastic energy conversion capacity. 展开更多
关键词 triaxial extension energy distribution fracture mode energy dissipation energy storage
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SWAT和WetSpa Extension在罗玉沟流域的应用比较 被引量:2
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作者 韩旖旎 牛健植 张由松 《水资源与水工程学报》 2014年第3期133-137,共5页
近年来,运用水文模型来研究流域水文状况越来越普遍,本文以黄土高原丘陵沟壑区第三副区的典型小流域为例,基于SWAT和WetSpa Extension两个模型,从模型的输入数据、模型的参数和模型模拟结果等方面进行比较,以期为该区水沙模拟选择合适... 近年来,运用水文模型来研究流域水文状况越来越普遍,本文以黄土高原丘陵沟壑区第三副区的典型小流域为例,基于SWAT和WetSpa Extension两个模型,从模型的输入数据、模型的参数和模型模拟结果等方面进行比较,以期为该区水沙模拟选择合适水文模型并为将来模型性能的改进提供参考。连续15年的校准验证表明:两个模型都能得到较好的结果,而SWAT模型能应用于水文及泥沙等模拟过程,相对来说功能更全面;WetSpa Extension模型目前仅能提供水文模拟的模块,优点在于模拟时间步长较任意,可进行洪水模拟。 展开更多
关键词 SWAT模型 WetSpa extension模型 分布式模型 罗玉沟流域 水文模拟
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Extension集合辨析 被引量:2
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作者 左静 《郑州工业大学学报》 2001年第2期20-22,共3页
xtension集合是可拓学理论的基础概念之一 .探讨Extension集合的特色和它与其它集合的关系 ,对于明晰可拓学的生存基础、研究价值和发展前景非常重要 .通过比较 3种集合对论域元素的识别与分类原则 ,指出Fuzzy集合Extension集合均以Can... xtension集合是可拓学理论的基础概念之一 .探讨Extension集合的特色和它与其它集合的关系 ,对于明晰可拓学的生存基础、研究价值和发展前景非常重要 .通过比较 3种集合对论域元素的识别与分类原则 ,指出Fuzzy集合Extension集合均以Cantor集合为基础 ,但各自又具有其它集合不可替代的独特之处 .Extension集合的特色在于它对论域元素潜在属性的识别角度和元素属性在特定变换下的可转换性的识别功能 . 展开更多
关键词 extension集合 CANTOR集合 FUZZY集合 可拓学 论域元素 关联函数
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岩石圈伸展的壳/幔拆离模型(Parallel Extension Tectonics):华北克拉通东部早白垩世岩石圈减薄与破坏机理 被引量:15
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作者 刘俊来 倪金龙 +4 位作者 陈小宇 Craddock JP 郑媛媛 孙彦琪 季雷 《岩石学报》 SCIE EI CAS CSCD 北大核心 2020年第8期2331-2343,共13页
华北克拉通岩石圈减薄和破坏机理长期以来存在争议,基于岩石学、岩石地球的化学分析研究突出强调深部过程的重要性。前人提出了两种重要模式:包括以拆沉作用为代表的top-down tectonics模型和以热-机械侵蚀与化学侵蚀,或地幔置换、交代... 华北克拉通岩石圈减薄和破坏机理长期以来存在争议,基于岩石学、岩石地球的化学分析研究突出强调深部过程的重要性。前人提出了两种重要模式:包括以拆沉作用为代表的top-down tectonics模型和以热-机械侵蚀与化学侵蚀,或地幔置换、交代作用的bottom-up tectonics模型。然而,对于这两种模式而言尚存在许多无法合理解释的问题,比如在此深部过程中,区域性岩石圈伸展有多大的贡献?地壳伸展构造是作为深部过程的响应,还是同为岩石圈伸展的产物?本文基于早白垩世东亚地区(尤其是华北克拉通东部地区)伸展构造与岩浆活动的综合分析,揭示出华北克拉通东部不同地区伸展构造变形与岩浆活动之间的时、空和成因关系有一定的差异。但整体上看,岩石圈伸展起着主导作用,控制着岩浆上侵和就位,在拆离断层下盘侵入形成各种规模的花岗质为主的侵入体,或于上盘喷发形成火山-沉积岩盆地。在伸展构造发育的不同阶段,可以有伸展早期、伸展期及伸展期后的岩浆活动。岩浆活动的强度及岩浆源区特点有显著的时空变化。一方面,在同一地区不同演化阶段其源区有很大的差异。表现为主体上是早期以古老下地壳源为主,随着壳/幔伸展作用演化,逐渐向混合源或独立幔源的演化。同时,不同地区岩浆源区的变化规律也显著不同。以胶辽地区为例,胶东整体上是壳幔混合源区对于岩浆演化有重要贡献;而辽东地区具有显著的源区演化特点:从剪切早期古老下地壳源区为主,并伴有幔源物质加入,剪切期古老下地壳为主,到剪切晚期和剪切期后以新生下地壳为主。本文认为岩石圈伸展的壳/幔拆离模型(Parallel Extension Tectonics),可以合理地解释华北克拉通及邻区早白垩世构造-岩浆活动性。在该模型中,遭受伸展的华北克拉通岩石圈发生壳-幔拆离作用。在岩石圈伸展作用期间,地壳层次的拆离作用与岩石圈地幔层次上的拆离作用可以是耦合的或者是解耦的,从而导致华北克拉通岩石圈减薄过程中在地壳尺度上的拆离作用与变质核杂岩的剥露有三种不同的类型:同岩浆活动型伸展(C型:Co-magmatism mode extension)、无岩浆活动型伸展(A型:Amagmatism mode extension)和多阶段混合型(M型:Multi-mode extension)。 展开更多
关键词 岩石圈不均匀伸展 壳幔拆离 同伸展岩浆作用 岩石圈伸展的壳幔拆离模型 华北克拉通
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Assessment of bearing performance degradation via extension and EEMD combined approach 被引量:18
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作者 LIU Yu-mei ZHAO Cong-cong +3 位作者 XIONG Ming-ye ZHAO Ying-hui QIAO Ning-guo TIAN Guang-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1155-1163,共9页
As a key component in rotating machinery, the operating reliability of bearing influences the performance and service life of the equipment directly. In order to describe bearing performance degradation(BPD) process e... As a key component in rotating machinery, the operating reliability of bearing influences the performance and service life of the equipment directly. In order to describe bearing performance degradation(BPD) process effectively, an assessment approach combining extension and ensemble empirical mode decomposition(EEMD) was proposed. First, the extension was utilized to construct the matter-element of bearing operating state, and the energy moment of intrinsic mode functions(IMFs) was used as characteristic parameter of the matter-element. Then, to determine classical domains of characteristic parameters, the mathematical statistics method was adopted. Finally, the BPD was analyzed qualitatively and quantitatively according to the comprehensive correlation degree of bearing current operating state related to its healthy state. The analytic results of bearing test-rig show that the proposed method indicates the incipient fault approximately occurring in the 81 st hour, and the method also quantitatively presents the degree of BPD. By contrast, the BPD assessment based on time-domain features extraction method could not achieve the above two results effectively. 展开更多
关键词 BEARING performance degradation ASSESSMENT extension ENSEMBLE empirical mode decomposition MATHEMATICAL STATISTICS
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Application of extension neural network to safety status pattern recognition of coalmines 被引量:6
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作者 周玉 W.Pedrycz 钱旭 《Journal of Central South University》 SCIE EI CAS 2011年第3期633-641,共9页
In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of... In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of network,the rationale of recognition algorithm and the performance of proposed method were discussed in detail.The safety status pattern recognition problem of coalmines can be regard as a classification problem whose features are defined in a range,so using the ENN is most appropriate for this problem.The ENN-based recognition method can use a novel extension distance to measure the similarity between the object to be recognized and the class centers.To demonstrate the effectiveness of the proposed method,a real-world application on the geological safety status pattern recognition of coalmines was tested.Comparative experiments with existing method and other traditional ANN-based methods were conducted.The experimental results show that the proposed ENN-based recognition method can identify the safety status pattern of coalmines accurately with shorter learning time and simpler structure.The experimental results also confirm that the proposed method has a better performance in recognition accuracy,generalization ability and fault-tolerant ability,which are very useful in recognizing the safety status pattern in the process of coal production. 展开更多
关键词 safety status pattern recognition extension neural network coal mines
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PETROLOGY AND AGE OF THE KINNAR KAILAS GRANITE:EVIDENCES FOR AN ORDOVICIAN POST-OROGENIC EXTENSION IN THE HIGHER HIMALAYAN CRYSTALLINE, SUTLEJ, INDIA 被引量:4
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作者 H. S. Chawla\+1, D. Marquer\+1, J. D. Kramers\+2, I. M. Villa\+2, F. Bussy\+3(1 Geological Institute, Emile Argand, 11, 2007, Neuchatel, Switzerland 2 Isotopengeologie, Erlachstrasse 9a, 3012 Bern, Switzerland 3 Institute of Mineralogy and Geochemi 《地学前缘》 EI CAS CSCD 2000年第S1期50-51,共2页
Higher Himalayan Crystalline (HHC) rocks often show metamorphic zonations from lower greenschist facies to migmatites associated with leucogranite intrusions that are classically described as examples of Tertiary inve... Higher Himalayan Crystalline (HHC) rocks often show metamorphic zonations from lower greenschist facies to migmatites associated with leucogranite intrusions that are classically described as examples of Tertiary inverted metamorphism. The present study, based on structural, petrological and geochronological investigations in the Kinnar Kailas Granite (KKG) and surrounding HHC sequence, evidences a discordant intrusive contact of the Ordovician KKG with respect to Pre\|Alpine high grade deformed HHC sequence in the Sutlej valley.Four main phases of deformation are recorded in this HHC sequence and pre\|Ordovician sediments. The first three phases of deformation occurred under high\|grade metamorphic conditions, before the intrusion of the KKG. The geometry of the main progressive ductile deformation (D2—D3) results from SW vergent doming and migmatisation. The latest deformation is expressed by local shearing under greenschist facies conditions. This late D4 deformation corresponds to N—S oriented ductile normal faults lowering the eastern blocks. The KKG is a shallow depth intrusion, showing discordant contacts with the surrounding basement rocks and large scale magmatic stoping. The KKG crosscuts the high\|grade deformation structures (D2—D3) but is locally affected by the local late D4 extensional deformation. The granite textures reflect only slight orientation related to magmatic deformation and even at few centimetres from the intrusion contact, the granite appears undeformed in contrast to the surrounding highly foliated rocks. Furthermore, xenoliths of Kyanite\|Sillimanite bearing basement rocks are present within the KKG. 展开更多
关键词 HIGHER Himalaya CRYSTALLINE GRANITE ORDOVICIAN post\|orogenic extension
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Application of extension method to fault diagnosis of transformer 被引量:4
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作者 邓宏贵 曹建 +1 位作者 罗安 夏向阳 《Journal of Central South University of Technology》 EI 2007年第1期88-93,共6页
A novel extension diagnosis method was proposed for enhancing the diagnosis ability of the conventional dissolved gas analysis. Based on the extension theory a matter-element model was established for qualitatively an... A novel extension diagnosis method was proposed for enhancing the diagnosis ability of the conventional dissolved gas analysis. Based on the extension theory a matter-element model was established for qualitatively and quantitatively describing the fault diagnosis problem of power transformers. The degree of relation based on the dependent functions was employed to determine the nature and the grade of the faults in a transformer system. And the proposed method was verified with the experimental data. The results show that accuracy rate of the diagnosis method exceeds 90% and two kinds of faults can be detected at the same time. 展开更多
关键词 power transformer fault diagnosis extension theory matter-element model dependent function
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Feature extension and matching for mobile robot global localization 被引量:1
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作者 Peng Wang Qibin Zhang Zonghai Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第4期840-846,共7页
This paper introduces an indoor global localization method by extending and matching features. In the proposed method, the environment is partitioned into convex subdivisions. Local extended maps of the subdivisions a... This paper introduces an indoor global localization method by extending and matching features. In the proposed method, the environment is partitioned into convex subdivisions. Local extended maps of the subdivisions are then built by exten- ding features to constitute the local extended map set. While the robot is moving in the environment, the local extended map of the current local environment is established and then matched with the local extended map set. Therefore, global localization in an indoor environment can be achieved by integrating the position and ori- entation matching rates. Both theoretical analysis and comparison experimental result are provided to verify the effectiveness of the proposed method for global localization. 展开更多
关键词 feature extension global localization feature match-ing mobile robot.
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THE EXTENSIONAL MOVEMENT AND ACTION IN THE SOUTHERN TIBET SINCE HERCYNIAN
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作者 Wang Genhou,Gao Jinhan,Liang Dingyi(China University of Geosciences, Beijing 100083,China) 《地学前缘》 EI CAS CSCD 2000年第S1期60-61,共2页
Based on the study of the location of extensional action in the tectonic background and the state of regional tectonic stress, the extensional action can be distinguished into active and passive types. The active exte... Based on the study of the location of extensional action in the tectonic background and the state of regional tectonic stress, the extensional action can be distinguished into active and passive types. The active extensional movement is mainly composed of a set of deposition formed under extensional stress and syntectonic and syndepositional deformational structure. The passive extentional movement is expressed as regional extensional action induced under the compressional elevation. Extensional movement and action are well\|developed in the Tibet\|Tethys domain. By the analysis of tectonic deformation, extensional unconformity, depositional facies and paleogeographical rebuilding in the South Tibet, it is recognized that the extensional movement consists of active extension of Hercynian, Indo\|China and Early Yanshan epochs, and the passive extension of Late Yanshan and Himalayan epochs. Some of the characteristics of extensional movement and structures are discussed in this paper(Table.1). 展开更多
关键词 Southern Tibet extensionAL MOVEMENT extensionAL UNCONFORMITY Hercynian—Early Yanshan EPOCH
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Structural integrity and life extension of high-temperature components
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作者 汪淳 沈士明 《Journal of Central South University》 SCIE EI CAS 2005年第S2期45-52,共8页
Four different topics for high-temperature components, namely the development of the assessment codes for the structural integrity of high-temperature components, the application of continuous damage mechanics and pro... Four different topics for high-temperature components, namely the development of the assessment codes for the structural integrity of high-temperature components, the application of continuous damage mechanics and probabilistic damage mode on the life assessment of high-temperature components, the life extension for high-temperature components and a proposed strategy for remanufacturing of high-temperature components were discussed in this paper. These topics should provide some important insights for the design and re-design of high- temperature components. 展开更多
关键词 INTEGRITY LIFE extension COMPONENT REMANUFACTURING CREEP
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Acceptability of Bush Meat as a Source of Animal Protein in Delta State, Nigeria: Implication for Extension Services
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作者 Ebewore S O Ovharhe O J Emaziye P O 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期67-78,共12页
The study examined the acceptability ofhnsh meat to Deltans. The specific objectives were to ascertain the consumption pattern of bush meat; identify the major types of bush meat consumed in the area; determine the li... The study examined the acceptability ofhnsh meat to Deltans. The specific objectives were to ascertain the consumption pattern of bush meat; identify the major types of bush meat consumed in the area; determine the likely constraints to bush meat consumption; and stipulate the extension implication of the findings. A systematic sampling technique was used to compose a sample size of 410 respondents. Data used for this study were collected using well structured interview schedule and data were analyzed using descriptive statistical techniques such as tables, percentages, means and standard deviation, and inferential statistics (linear regression model). The result of the study indicated that almost all the respondents (402) representing about 98% was formally consuming bush meat. The findings also revealed that as many as 323 individuals, representing 78.8% of the respondents did not consume bush meat currently. Only about 12.7% and 8.5% occasionally and regularly consumed bush meat respectively. It was therefore very obvious that people no longer consumed bush meat in Delta state as before. The results further indicated that the predominant bush meat consumed in the area were cane rat (97.70%) and the African giant snails (Achatina and Archachatina) (94.25%). The result of the multiple regression analyses indicated that the coefficient for education (X3), income (Xs), Ebola (X6) and availability of game (XT) were significant at 5%, indicating that these variables were important factors influencing the consumption of bush meat in the study area. However, the coefficients of education level and Ebola factor were negative and significant, suggesting respondents with higher education and aware of Ebola disease were not likely to consume bush meat. As the result, it was concluded that bush meat was now almost unacceptable due to several factors like dread of Ebola disease, unavailability of game, educational level and income, which significantly affected the consumption of bush meat. It was therefore recommended among others that extension delivery services on how to domesticate game species should be available to farmers. 展开更多
关键词 game ACCEPTABILITY EBOLA extension Cane rat DELTA NIGERIA
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绵阳-长宁拉张槽东北缘埃迪卡拉系灯影组上部地层缺失及构造意义 被引量:3
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作者 丁一 刘树根 +9 位作者 文龙 马奎 陈代钊 宋金民 王瀚 王林康 陈明思 杨钹 唐攀 李智武 《地质学报》 北大核心 2025年第2期352-364,共13页
尽管绵阳-长宁拉张槽的油气地质意义已经得到广泛认可,其时空分布及成因机制自发现以来争议不断。在此背景下,本文对拉张槽北段东缘广元—宁强地区的震旦系(国际上称埃迪卡拉系)—寒武系过渡地层开展了系统的地层序列、岩相分析工作。... 尽管绵阳-长宁拉张槽的油气地质意义已经得到广泛认可,其时空分布及成因机制自发现以来争议不断。在此背景下,本文对拉张槽北段东缘广元—宁强地区的震旦系(国际上称埃迪卡拉系)—寒武系过渡地层开展了系统的地层序列、岩相分析工作。特征岩相及生物地层表明宽川铺、舒家坝、曹家坝—东山子地区普遍出现碑湾段下部甚至藻白云岩段上部与宽川铺组不整合接触,反映了高家山段和碑湾段的广泛缺失。该地层缺失区可以与川中—北斜坡地区连成一线。研究区灯影组以局限潮坪—潟湖环境的藻白云岩及泥晶白云岩沉积为主,而西侧的大滩—羊木地区灯影组截然变化为斜坡—盆地相硅质岩沉积,指示同沉积伸展断层的活动。这种相带突变样式在中扬子台地南缘和上扬子台地东缘也有发育,反映了整个中上扬子地区在震旦纪—寒武纪转折期总体处于伸展背景,广泛发育断控型碳酸盐岩台地边缘。绵阳-长宁拉张槽巨大的宽度(数十千米)、剥蚀厚度(数百米)及灯影组顶部长期的沉积间断(近20 Ma)说明其形成与差异升降作用有关,难以用岩溶地貌解释。考虑到研究区与川中—北斜坡的灯影组上段的缺失区总体呈线状分布,可用断层上盘的掀斜作用引起相对抬升来解释。伸展断层活动的高峰期大致可以约束在灯影组沉积晚期到麦地坪组沉积初期,对应灯影组上部到宽川铺组底部的广泛缺失。 展开更多
关键词 绵阳-长宁拉张槽 灯影组 地层缺失 伸展背景 断控
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塔里木盆地顺南—古隆地区断裂发育特征及成因机制
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作者 黄诚 林波 +2 位作者 张胜 王岳丰 于福生 《特种油气藏》 北大核心 2025年第3期8-15,共8页
针对顺南—古隆地区断裂系统的性质、演化期次及成因机制存在认识分歧的问题,通过地震解释、地震属性提取、断层活动强度统计、区域构造背景等分析,对研究区断裂系统开展研究。结果表明:该区北东东向断裂为加里东早期被动大陆边缘阶段... 针对顺南—古隆地区断裂系统的性质、演化期次及成因机制存在认识分歧的问题,通过地震解释、地震属性提取、断层活动强度统计、区域构造背景等分析,对研究区断裂系统开展研究。结果表明:该区北东东向断裂为加里东早期被动大陆边缘阶段发育的伸展正断层,动力来源于阿尔金洋裂开过程产生的北西—南东向伸展作用,该组断裂在加里东中期复活形成“P”破裂;北东向断裂为加里东中期压扭阶段形成的广布式左行走滑断层,应力来源于阿尔金洋在关闭过程中产生的北西—南东向挤压作用;北北西向断裂为加里东晚期—海西中期基底走滑形成的张性破裂,应力来源于南天山洋闭合过程产生的近南北向挤压作用;车尔臣断裂走向分段活动差异是导致塔中Ⅰ号断裂分段活动并控制北东向压扭性走滑断裂广布式发育的主要原因。走滑断裂带的构造特征对储层规模、油气运移具有重要意义。该研究成果可为深入分析顺南—古隆地区走滑断裂发育过程及油气成藏关系分析提供理论依据,为研究区及周边油气勘探奠定基础。 展开更多
关键词 塔里木盆地 顺南—古隆地区 走滑断层 伸展断层 成因机制
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多期裂陷盆地斜向伸展变形主控因素分析--来自砂箱物理模拟实验的启示
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作者 王琦 孙永河 +3 位作者 巩磊 王有功 常德双 张万福 《石油实验地质》 北大核心 2025年第2期441-450,共10页
为了探讨多期裂陷盆地中先存断裂及其与不同伸展方向之间夹角(斜度α)对斜向伸展变形和洼槽结构的影响,利用砂箱物理模拟实验,基于相似性原理,设计了三组物理模拟实验,即不同斜度(α)斜向伸展物理模拟实验和两组斜向伸展—走滑叠加变形... 为了探讨多期裂陷盆地中先存断裂及其与不同伸展方向之间夹角(斜度α)对斜向伸展变形和洼槽结构的影响,利用砂箱物理模拟实验,基于相似性原理,设计了三组物理模拟实验,即不同斜度(α)斜向伸展物理模拟实验和两组斜向伸展—走滑叠加变形物理模拟实验。实验结果表明:(1)多期裂陷盆地中,伸展方向与先存断裂之间的夹角变化控制着走向滑动分量和倾向滑动分量的比例,影响洼槽结构,夹角越大,倾向滑动分量越大,洼槽宽度越大;反之,洼槽宽度减小。(2)受先存断裂分布的影响,不同演化阶段,先存断裂再活动方式不同,对于斜向伸展—走滑叠加变形过程,先存走滑断裂与边界断裂之间的距离较大时,洼槽呈单断半地堑特征;二者间距较小时,走滑断裂也控陷,洼槽呈现双断地堑结构。(3)多方位展布的先存边界断裂再活动控制形成的洼槽深度和压扭褶皱幅度也受二者距离的影响,随着先存边界断裂与走滑断裂距离的增加,张扭区洼槽深度逐渐增大,压扭区褶皱幅度逐渐增加;反之,洼槽深度越小,褶皱幅度越低。 展开更多
关键词 斜向伸展变形 断裂变形 盆地构造 物理模拟 多期裂陷盆地
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特提斯喜马拉雅双伸展复合成穹作用:来自定日穹隆构造变形和年代学的证据
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作者 李虎 唐菊兴 +4 位作者 吴青松 代雪健 代宏睿 刘涛 魏阳春 《岩石学报》 北大核心 2025年第5期1797-1817,共21页
北喜马拉雅片麻岩穹隆是喜马拉雅造山带的重要组成部分, 经历了多期构造变形和岩浆事件, 记录了印度-欧亚板块俯冲汇聚、碰撞造山历史。迄今为止, 其形成过程所经历的变形序列、动力学特征和成因机制尚存争议, 关键构造-岩浆事件和时间... 北喜马拉雅片麻岩穹隆是喜马拉雅造山带的重要组成部分, 经历了多期构造变形和岩浆事件, 记录了印度-欧亚板块俯冲汇聚、碰撞造山历史。迄今为止, 其形成过程所经历的变形序列、动力学特征和成因机制尚存争议, 关键构造-岩浆事件和时间亟待明确。本文报道了该带中段与南北向裂谷相关的定日穹隆物质组成、构造变形、运动学和年代学特征。揭示出定日穹隆物质组成和构造变形"4+4"模式, 即由上、下主拆离断层为界, 分为上部、中部、下部岩石-构造单元和核部花岗岩体, 其上、中部单元属浅变质特提斯喜马拉雅沉积岩系, 下部单元为高喜马拉雅结晶基底拆离出露, 核部侵位淡色花岗岩。穹隆体构造变形经历了早期N-S逆冲挤压、前期近N-S向伸展、主期E-W伸展和晚期垮塌伸展变形。穹隆就位继承了中生代特提斯喜马拉雅物质组成和挤压构造变形, ~22.1Ma的N-S向伸展, 岩浆初始就位;~17.1Ma与E-W向伸展相关的岩浆主体侵位, 并于14.4~14.1Ma冷却;12.5~12.0Ma南北向裂谷开启, 穹隆持续垮塌变形。在此基础上, 本文建立了成穹作用4个阶段, 即继承期、启动期、成穹期和垮塌期。结合构造变形、年代学及前人研究成果认为, 定日穹隆是STDS向北拆离N-S伸展和浅地壳尺度由于挤压应力的水平或垂向分量作用下E-W向伸展减压-熔融, 岩浆底劈共同作用结果, 属渐进造山, 双伸展复合成穹, 是对喜马拉雅造山事件的具体响应。本文的研究成果对北喜马拉雅片麻岩穹隆体形成机制及动力学探讨起到重要作用。 展开更多
关键词 北喜马拉雅片麻岩穹隆 定日穹隆 构造变形 年代学 双伸展复合成穹 成因机制
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Research on Denoising Method of Agricultural Product Terahertz Spectroscopy Based on Adaptive Signal Decomposition
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作者 WU Jing-zhu LIU Yu-hao +3 位作者 YANG Yi XIE Chuan-luan L Zhong-ming LI Yi-can 《光谱学与光谱分析》 北大核心 2025年第12期3575-3584,共10页
To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explo... To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explores the feasibility of adaptive-signal-decomposition-based denoising methods to improve THz spectral quality.THz time-domain spectroscopy(THz-TDS)combined with an attenuated total reflection(ATR)accessory was used to collect THz absorbance spectra from 48 peanut samples.Taking the quantitative prediction model of peanut moisture content based on THz-ATR as an example,wavelet transform(WT),empirical mode decomposition(EMD),local mean decomposition(LMD),and its improved methods-segmented local mean decomposition(SLMD)and piecewise mirror extension local mean decomposition(PME-LMD)-were employed for spectral denoising.The applicability of different denoising methods was evaluated using a support vector regression(SVR)model.Experimental results show that the peanut moisture content prediction model constructed after PME-LMD denoising achieved the best performance,with a root mean square error(RMSE),coefficient of determination(R^(2)),and mean absolute percentage error(MAPE)of 0.010,0.912,and 0.040,respectively.Compared with traditional methods,PME-LMD significantly improved spectral quality and model prediction performance.The PME-LMD denoising strategy proposed in this study effectively suppresses non-uniform noise interference in THz spectral signals,providing an efficient and accurate preprocessing method for THz spectral analysis of agricultural products.This research provides theoretical support and technical guidance for the application of THz technology for detecting agricultural product quality. 展开更多
关键词 Terahertz spectroscopy Denoising method Agricultural products Support vector regression Piecewise mirror extension local mean decomposition
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东海盆地西湖凹陷孔雀亭区断裂体系特征及控藏效应 被引量:3
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作者 薛煜恒 李坤 +3 位作者 尚娅敏 陈秋佟 盛烈豪 刘建斌 《岩性油气藏》 CAS 北大核心 2025年第1期161-169,共9页
以三维地震精细解释为基础,运用构造剖面复原、流体包裹体分析等方法,对东海盆地西湖凹陷孔雀亭区断裂体系特征进行了分析,并对其演化特征及控藏效应进行了研究。研究结果表明:①西湖凹陷孔雀亭区断裂体系具有明显东、西分区、分带特征... 以三维地震精细解释为基础,运用构造剖面复原、流体包裹体分析等方法,对东海盆地西湖凹陷孔雀亭区断裂体系特征进行了分析,并对其演化特征及控藏效应进行了研究。研究结果表明:①西湖凹陷孔雀亭区断裂体系具有明显东、西分区、分带特征。平面上,东部发育3组方向主干伸展断裂,NNE向为主,NE向及近NS向次之,西部发育2组方向主干伸展断裂,NE向为主,NNE向次之;剖面上东部以多米诺式斜列构造样式为主,西部以同向断阶为主;自西向东可分为5个断阶带,东部发育2个反向断裂带,西部发育3个同向断裂带。②研究区断裂体系经历了断陷期、断-坳转换期、坳陷反转期以及区域沉降期4个演化阶段,断裂活动性表现出“东部为早强晚弱、西部为早弱晚强”差异演化特征。③研究区发育东部反向断槽-局部自圈油气藏和西部顺向断阶-岩性尖灭油气藏,其中东部的油气藏为双源供烃,是油气富集有利区,尤其是F2和F3断裂活动性强、断距较大,所控圈闭的面积和高度大,在平湖组富油、花港组下段富气,是有利勘探区。 展开更多
关键词 伸展断裂 断裂活动性 双源供烃 断裂控藏 反向断槽-局部自圈油气藏 顺向断阶-岩性尖灭油气藏 西湖凹陷 东海盆地
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大兴安岭南段内蒙古小大川铅锌铜矿黑云母二长花岗岩锆石U-Pb年龄、地球化学特征及其成矿背景 被引量:2
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作者 刘永强 吕志成 +1 位作者 王虎 程海明 《地质通报》 北大核心 2025年第2期404-423,共20页
【研究目的】大兴安岭南段新发现的小大川铅锌铜矿赋存于黑云母二长花岗岩体中,在空间上受到燕山晚期侵入岩的影响。其成岩成矿时代、岩石成因及成矿地质背景等尚不清楚,对其研究可以为区域内铅锌成矿规律提供新的依据。【研究方法】采... 【研究目的】大兴安岭南段新发现的小大川铅锌铜矿赋存于黑云母二长花岗岩体中,在空间上受到燕山晚期侵入岩的影响。其成岩成矿时代、岩石成因及成矿地质背景等尚不清楚,对其研究可以为区域内铅锌成矿规律提供新的依据。【研究方法】采集大兴安岭南段小大川铅锌铜矿黑云母二长花岗岩样品,进行岩相学、锆石U-Pb测年,岩石地球化学及Sr-Nd同位素分析。【研究结果】研究表明,小大川黑云母二长花岗岩的锆石U-Pb年龄为135.9±0.8 Ma和134.9±0.8 Ma,表明铅锌矿化发生在早白垩世。岩石地球化学特征显示,黑云母二长花岗岩富SiO_(2)(71.29%~72.92%)、K_(2)O+Na_(2)O(7.17%~7.89%)、Al_(2)O_(3)(13.35%~14.48%),贫MgO(0.61%~0.64%)、CaO(1.24%~1.73%),富集Nb、Ta、Zr、Hf、Th元素,亏损Ba、K、Sr、P、Ti元素且稀土元素配分型式呈“海鸥型”分布,δEu值为0.35~0.47,负Eu异常明显,属于高钾钙碱性、过铝质A2型花岗岩。Sr-Nd同位素特征显示(87Sr/86Sr)i值为0.70545~0.70548,ε_(Nd)(t)值为-1.7~-0.3,Nd同位素的二阶段模式年龄为957~1071 Ma。【结论】结合年代学特征及地球化学特征,认为岩石成因为新生地壳和幔源物质混合同时受到上地壳混染。小大川黑云母二长花岗岩形成于蒙古-鄂霍茨克洋闭合造山后的伸展环境,该环境同时还导致了区域内成岩成矿作用的发生。 展开更多
关键词 大兴安岭南段 小大川铅锌铜矿床 黑云母二长花岗岩 锆石U-PB定年 SR-ND同位素 伸展环境
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