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D-/S-结构的清除:最简主义句法操作的经济性原则研究 被引量:1
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作者 南潮 《中南大学学报(社会科学版)》 2009年第2期286-290,共5页
为了限制转换规则和短语结构规则,生成语法专门设立了一些句法条件,即语法模块(grammar modules),包括D-结构层面的X-标杆理论、PP/EPP和题元理论;S-结构层面的格理论、空语类原则ECP、约束理论等。运用这些理论,管约论时期的生成语法... 为了限制转换规则和短语结构规则,生成语法专门设立了一些句法条件,即语法模块(grammar modules),包括D-结构层面的X-标杆理论、PP/EPP和题元理论;S-结构层面的格理论、空语类原则ECP、约束理论等。运用这些理论,管约论时期的生成语法成功地解释了一些句法现象,但还有不少句法问题无法解决。于是,在最简方案框架内,D-结构和S-结构从句法操作过程中被清除,认知系统和句法系统之间形成接口层面:LF和PF,合格的句法推导必须满足接口条件(interface conditions)。从语法模块到接口条件的转变,实际上是一个遵循着经济性原则,对普遍语法原则和规则进行简化或是清除的过程。 展开更多
关键词 D-结构 s-结构 语法模块 接口条件 经济性原则
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英语中动句的S-结构语义强化生成模型假设
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作者 仝毅然 《四川教育学院学报》 2010年第9期94-96,共3页
由中动词构成的句子称为中动句。过去对中动句生成的研究多集中在题元理论和格理论上。从语义影响句法的角度出发,中动句的形成是一个持续渐进的过程,而语义强化是推动句子结构一步步由深层结构到表层中动结构发展的主要动力,并据此提... 由中动词构成的句子称为中动句。过去对中动句生成的研究多集中在题元理论和格理论上。从语义影响句法的角度出发,中动句的形成是一个持续渐进的过程,而语义强化是推动句子结构一步步由深层结构到表层中动结构发展的主要动力,并据此提出中动结构生成的渐进模型。 展开更多
关键词 中动词 中动结构 s-结构 T-模式
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S-粗集和它的一般结构 被引量:174
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作者 史开泉 崔玉泉 《山东大学学报(理学版)》 CAS CSCD 北大核心 2002年第6期471-474,共4页
给出论域U上元素迁移F ,F ,单向奇异集合 ,双向奇异集合的概念 ;利用这些概念 ,提出奇异粗集 ,简称S 粗集 ,给出S 粗集的数学结构 ,S 粗集的存在背景和意义解释 .S 粗集包含两种结构 :单向S 粗集 ,双向S 粗集 ;S 粗集是研究系统动态近... 给出论域U上元素迁移F ,F ,单向奇异集合 ,双向奇异集合的概念 ;利用这些概念 ,提出奇异粗集 ,简称S 粗集 ,给出S 粗集的数学结构 ,S 粗集的存在背景和意义解释 .S 粗集包含两种结构 :单向S 粗集 ,双向S 粗集 ;S 粗集是研究系统动态近似特性 ,知识挖掘 ,知识发现的一个新的理论工具 . 展开更多
关键词 s-集合 s-粗集 s-结构 迁移平衡定理 外迁移淹没定理 内迁移淹没定理
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序S-系的定义及简单性质
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作者 王文康 《西北民族大学学报(自然科学版)》 2003年第3期5-6,共2页
将半群的S 系理论与序半群理论结合起来,形成了序S 系的理论 在序左S 系定义的基础上,给出序左S 系的几条等价定义,提出序左S 结构子系的概念,以便论述序左S
关键词 s- 半群 s-系理论 序半群理论 序左s- 序左s-结构子系
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函数S-粗集 被引量:76
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作者 史开泉 《山东大学学报(理学版)》 CAS CSCD 北大核心 2005年第1期1-6,10,共7页
利用S 粗集 (singularroughsets) ,提出了函数S 粗集 ,给出了函数S 粗集的数学结构和特性 函数S 粗集具有两类形式 :函数单向S 粗集 ,函数双向S 粗集 .提出了函数S 粗集与S 粗集的关系定理 .函数S 粗集是S 粗集的一般形式 ,S 粗集是函... 利用S 粗集 (singularroughsets) ,提出了函数S 粗集 ,给出了函数S 粗集的数学结构和特性 函数S 粗集具有两类形式 :函数单向S 粗集 ,函数双向S 粗集 .提出了函数S 粗集与S 粗集的关系定理 .函数S 粗集是S 粗集的一般形式 ,S 粗集是函数S 粗集的特例 .函数S 粗集是粗集研究的一个新方向 . 展开更多
关键词 函数s-粗集 函数s-粗集的结构 关系定理
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S-粗信息矩阵与它的两类形式 被引量:3
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作者 郝秀梅 《山东大学学报(理学版)》 CAS CSCD 北大核心 2008年第1期91-94,102,共5页
利用粗信息矩阵,提出了S-粗信息矩阵概念,给出了S-粗信息矩阵的结构和特征。S-粗信息矩阵具有两类形式:单向S-粗信息矩阵,单向对偶S-粗信息矩阵,双向S-粗信息矩阵。给出了S-粗信息矩阵与粗信息矩阵、S-粗集、Z.Pawlak粗集的关系定理。
关键词 信息矩阵 粗信息矩阵 单向对偶s-粗信息矩阵 s-粗信息矩阵的结构
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多元函数单向S-粗集 被引量:1
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作者 杜素勤 《甘肃联合大学学报(自然科学版)》 2007年第4期4-7,共4页
给出了二元函数单向S-粗集的数学结构和特性.提出了二元函数单向S-粗集与一元函数单向S-粗集、单向S-粗集的关系定理,二元函数单向S-粗集与二元函数粗集的关系定理.最后以实例说明二元函数单向S-粗集的存在.
关键词 二元函数单向s-粗集 二元函数单向s-粗集的结构 关系定理
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Construction of 3D flowers-like O-doped g-C_(3)N_(4)-[N-doped Nb2O5/C]heterostructure with direct S-scheme charge transport and highly improved visible-light-driven photocatalytic efficiency 被引量:3
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作者 Fahim A.Qaraah Samah A.Mahyoub +3 位作者 Abdo Hezam Amjad Qaraah Qasem A.Drmosh Guangli Xiu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2637-2651,共15页
Constructing a suitable heterojunction photocatalytic system from two photocatalytic materials is an efficient approach for designing extremely efficient photocatalysts for a broader range of environmental,medical,and... Constructing a suitable heterojunction photocatalytic system from two photocatalytic materials is an efficient approach for designing extremely efficient photocatalysts for a broader range of environmental,medical,and energy applications.Recently,the construction of a step-scheme heterostructure system(hereafter called the S-scheme)has received widespread attention in the photocatalytic field due to its ability to achieve efficient photogenerated carrier separation and obtain strong photo-redox ability.Herein,a novel S-scheme heterojunction system consisting of 2D O-doped g-C_(3)N_(4)(OCN)nanosheets and 3D N-doped Nb_(2)O_(5)/C(N-NBO/C)nanoflowers is constructed via ultrasonication and vigorous agitation technique followed by heat treatment for the photocatalytic degradation of Rhodamine B(RhB).Detailed characterization and decomposition behaviour of RhB showed that the fabricated material shows excellent photocatalytic efficiency and stability towards RhB photodegradation under visible-light illumination.The enhanced performance could be attributed to the following factors:fast charge transfer,highly-efficient charge separation,extended lifetime of photoinduced charge carriers,and the high redox capability of the photoinduced charges in the S-scheme system.Various trapping experiment conditions and electron paramagnetic resonance provide clear evidence of the S-scheme photogenerated charge transfer path,meanwhile,the RhB mineralization degradation pathway was also investigated using LC-MS.This study presents an approach to constructing Nb_(2)O_(5)-based S-scheme heterojunctions for photocatalytic applications. 展开更多
关键词 2D/3D nanostructure s-scheme heterojunction g-C_(3)N_(4) Nb_(2)O_(5) Photocatalytic degradation
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Reverse Engineering Analysis Based on Differential Fault Analysis Against Secret S- boxes 被引量:2
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作者 Tang Ming Qiu Zhenlong +2 位作者 Deng Hui Liu Shubo Zhang Huanguo 《China Communications》 SCIE CSCD 2012年第10期10-22,共13页
To evaluate the security of cipher algo- rithrrs with secret operations, we built a new reverse engineering analysis based on Differential Fault Analysis (DFA) to recover the secret S-boxes in Secret Private Network... To evaluate the security of cipher algo- rithrrs with secret operations, we built a new reverse engineering analysis based on Differential Fault Analysis (DFA) to recover the secret S-boxes in Secret Private Network (SPN) and Feistel structures, which are two of the most typical structures in block ciphers. This paper gives the general definitions of these two structures and proposes the reverse engineering analysis of each structure. Furthermore, we evaluate the complexity of the proposed reverse analyses and theoretically prove the effectiveness of the reverse method. For the Twoflsh-like and AES-like algorithrm, the experimental results verify the correctness and efficiency of the reverse analysis. The proposed reverse analysis can efficiently recover the secret S-boxes in the encryp'don algorithms writh SPN and Feistel structures. It can successfully recover the Twoflsh- like algorithm in 2.3 s with 256 faults and the AES- like algorithm in 0.33 s with 23 faults. 展开更多
关键词 DFA reverse engmeenng analysis block cipher SPN feistel s-BOX
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Design of S-Band Circularly Polarized Double-Layer Microstrip Antenna
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作者 李媛 赵方圆 +1 位作者 郭嘉 张磊 《Transactions of Tianjin University》 EI CAS 2012年第4期248-252,共5页
This paper proposes a compact polarization microstrip antenna based on double-layer structure. The band- width of the whole antenna is widened by expanding the top and bottom layers respectively. After the design of a... This paper proposes a compact polarization microstrip antenna based on double-layer structure. The band- width of the whole antenna is widened by expanding the top and bottom layers respectively. After the design of antenna structure and adjustment of size, the proposed antenna can achieve both the left- and right-hand circular polariza- tions in 2.33 GHz--2.97 GHz. Measurement results indicate that the effective bandwidth is 640 MHz in S-band and the relative bandwidth can achieve 24% with S, less than- 15 dB. 展开更多
关键词 double-layer microstrip antenna broadband antenna finite difference time domain circular polarization
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Seismogram Analysis of Earthquake C060394F,South Java: S-wave Velocity Structure
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作者 Bagus Jaya Santosa 《Earthquake Research in China》 2011年第3期310-319,共10页
The S wave velocity structure between the hypocenter of C060394F earthquake,South Java and a series of observatory stations located in Australia and South-East Asia have been investigated through seismogram analysis i... The S wave velocity structure between the hypocenter of C060394F earthquake,South Java and a series of observatory stations located in Australia and South-East Asia have been investigated through seismogram analysis in the time domain and the three Cartesian components.The synthetic seismogram is constructed from the PREMAN global earth model.Seismogram comparison between the measured and synthetic seismograms shows large discrepancies.A correction to the S wave velocity structure is needed to solve these discrepancies.Seismogram analysis and fitting at the observatory stations located in Australia show a positive anomaly,whereas the stations in South-East Asia show a strong negative anomaly.Vertical anisotropy occurred in the upper mantle layer and earth mantle layers beneath it.The seismogram analysis in the time domain and the three components simultaneously provides a better picture of the earth model,compared to the analysis of the seismogram with arrival time,travel time difference and dispersion analysis. 展开更多
关键词 Seismogram comparison Anomaly in the earth mantle Vertical anisotropy
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Hardness-Based Non-destructive Method for Developing Location Specific S-N Curves for Fatigue Life Evaluation
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作者 Chaminda S. Bandara Sudath C. Siriwardane +1 位作者 Udaya I. Dissanayake Ranjith Dissanayake 《Journal of Civil Engineering and Architecture》 2016年第2期183-191,共9页
This paper first describes the importance of using location specific S-N curves for fatigue damage assessment of existing steel structures. It discusses the existing concepts and methods for developing S-N curves usin... This paper first describes the importance of using location specific S-N curves for fatigue damage assessment of existing steel structures. It discusses the existing concepts and methods for developing S-N curves using empirical formulae and monotonic strength parameters, such as the ultimate tensile strength and hardness. It also discusses relationships among these monotonic parameters. Then it presents formulae for developing hardness-based full range S-N curves for medium strength steels. The formulae are verified using experimental data obtained from both monotonic and cyclic testing. Finally, it describes the advantages of these hardness-based formulae for developing location specific S-N curves as hardness testing is a non-destructive test which can be carried out on specific locations in structures. 展开更多
关键词 Stress life curve fatigue life HARDNESS steel structures non-destructive test.
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Synthesis and Crystal Structure of Mercury BridgedBiferrocene Trinuclear Complex Hg(FcL)_2,Bis(S-methyl-N-(1-ferrocenyl-1-methyl)methylenedithiocarbazate)mercury(Ⅱ) 被引量:1
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作者 DUAN Chun-Ying LIU Ze-Hua +1 位作者 TIAN Yu-Peng YOU Xiao-Zeng(Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry,Nanjing Univrsity, Nanjing, 210093) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1998年第1期1-4,共4页
The title complex, mercury bridged biferrocene trinuclear complex Hg(FcL)2. Bis (S-methyl-N- (1-ferrocenyl-1-methyl) methylenedithiocarbazate) mercury,Crystallizes in space group Pbca with a =19. 510 (4), b=19. 921 (5... The title complex, mercury bridged biferrocene trinuclear complex Hg(FcL)2. Bis (S-methyl-N- (1-ferrocenyl-1-methyl) methylenedithiocarbazate) mercury,Crystallizes in space group Pbca with a =19. 510 (4), b=19. 921 (5), c=15. 581 (3)A. V=6095(3) A, Z=8,M.=863. 12, Dc=1.881 g/cm3; u=19. 24 cm-1 and F(000) = 3376. The final refinement of 2455 observed reflections is converged with R= 0. 043 and Rw=0.047. X-ray crystal structure analysis revealed that the coordinationgeometry of Hg atom is a distorted tetrahedron with two Hg-N bonds and two Hg- S bonds. The Schiff-base ligand loses a proton from its tautomeric thiol form and is cryordianted to the Hg aotm uia the mercapto sulphur and the β-nitrogen atoms. 展开更多
关键词 mercury(Ⅱ) bridged biferrocene trinuclear complex crystal structure
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Hausdorff向量场
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作者 李洪军 《工程数学学报》 EI CSCD 北大核心 1997年第4期85-90,共6页
讨论了紧流形上的光滑无奇点向量场。建立了光滑无奇点向量场与流形的S-结构之间的一一对应。把轨道空间是Hausdorf空间的向量场称为Hausdorf向量场。Hausdorf向量场的轨道空间是一个余一维的光滑流形。本文... 讨论了紧流形上的光滑无奇点向量场。建立了光滑无奇点向量场与流形的S-结构之间的一一对应。把轨道空间是Hausdorf空间的向量场称为Hausdorf向量场。Hausdorf向量场的轨道空间是一个余一维的光滑流形。本文的主要结果是:n-维流形M上存在Hausdorf向量场的充要条件是M是某(n-1)-维流形上的光滑S1-纤维丛。 展开更多
关键词 无奇点向量场 s-结构 纤维丛 豪斯道夫向量场
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Method of Establishing Object-Oriented System Structure for Decision Support System 被引量:2
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作者 曹元大 胡军 管春 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期311-315,共5页
In order to solve existing problems about the method of establishing traditional system structure of decision support system(DSS), O S chart is applied to describe object oriented system structure of general DSS, an... In order to solve existing problems about the method of establishing traditional system structure of decision support system(DSS), O S chart is applied to describe object oriented system structure of general DSS, and a new method of eight specific steps is proposed to establish object oriented system structure of DSS by using the method of O S chart, which is applied successfully to the development of the DSS for the energy system ecology engineering research of the Wangheqiu country. Supplying many scientific effective computing models, decision support ways and a lot of accurate reliable decision data, the DSS plays a critical part in helping engineering researchers to make correct decisions. Because the period for developing the DSS is relatively shorter, the new way improves the efficiency of establishing DSS greatly. It also makes the DSS of system structure more flexible and easy to expand. 展开更多
关键词 decision support system object oriented technology system structure
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Vacancy engineering mediated hollow structured ZnO/ZnS S-scheme heterojunction for highly efficient photocatalytic H_(2) production
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作者 Fangxuan Liu Bin Sun +3 位作者 Ziyan Liu Yingqin Wei Tingting Gao Guowei Zhou 《Chinese Journal of Catalysis》 SCIE CAS 2024年第9期152-165,共14页
Designing a step-scheme(S-scheme)heterojunction photocatalyst with vacancy engineering is a reliable approach to achieve highly efficient photocatalytic H_(2)production activity.Herein,a hollow ZnO/ZnS S-scheme hetero... Designing a step-scheme(S-scheme)heterojunction photocatalyst with vacancy engineering is a reliable approach to achieve highly efficient photocatalytic H_(2)production activity.Herein,a hollow ZnO/ZnS S-scheme heterojunction with O and Zn vacancies(VO,Zn-ZnO/ZnS)is rationally constructed via ion-exchange and calcination treatments.In such a photocatalytic system,the hollow structure combined with the introduction of dual vacancies endows the adequate light absorption.Moreover,the O and Zn vacancies serve as the trapping sites for photo-induced electrons and holes,respectively,which are beneficial for promoting the photo-induced carrier separation.Meanwhile,the S-scheme charge transfer mechanism can not only improve the separation and transfer efficiencies of photo-induced carrier but also retain the strong redox capacity.As expected,the optimized VO,Zn-ZnO/ZnS heterojunction exhibits a superior photocatalytic H_(2) production rate of 160.91 mmol g^(-1)h^(-1),approximately 643.6 times and 214.5 times with respect to that obtained on pure ZnO and ZnS,respectively.Simultaneously,the experimental results and density functional theory calculations disclose that the photo-induced carrier transfer pathway follows the S-scheme heterojunction mechanism and the introduction of O and Zn vacancies reduces the surface reaction barrier.This work provides an innovative strategy of vacancy engineering in S-scheme heterojunction for solar-to-fuel energy conversion. 展开更多
关键词 Hollow structure ZnO/ZnS s-scheme heterojunction Vacancy engineering Photocatalytic H_(2) production
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《原则与参数》评介
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作者 陈华 《南昌高专学报》 2010年第1期56-57,70,共3页
《原则与参数》一书是由Ohio州立大学语言学院教授Culicover所著的教学用书。该书于1997年由牛津大学出版社正式出版发行。该书介绍的"原则参数"理论由以下几个子理论组成:题元理论、X阶标理论、格理论、约束理论、管辖理论... 《原则与参数》一书是由Ohio州立大学语言学院教授Culicover所著的教学用书。该书于1997年由牛津大学出版社正式出版发行。该书介绍的"原则参数"理论由以下几个子理论组成:题元理论、X阶标理论、格理论、约束理论、管辖理论、控制理论、界限理论。全书共分为十章,前两章介绍一些生成语法的基本概念和术语,后8章分别介绍各个子系统。该书是对句法理论的一个最基础的介绍,是理解当前句法革新的理论基础。 展开更多
关键词 生成语法 题元 论元s-结构 D-结构管辖 格X阶标 约束 移位 语障 逻辑式
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L-拓扑中的度量理论
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作者 史福贵 《模糊系统与数学》 CSCD 北大核心 2007年第1期1-11,共11页
对L-拓扑中已有度量理论的研究进展作一个简要的介绍和评述,力图使读者了解L-拓扑中度量理论的发展概况和发展方向。
关键词 L-拓扑 (点式)一致结构 (点式)度量 分离性 s-邻近结构
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Design and Implementation of Visualized Workflow Modeling System Based on B/S Structure 被引量:2
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作者 王坚 李巍丽 《Journal of Donghua University(English Edition)》 EI CAS 2007年第1期75-78,共4页
According to the necessity of flexible workflow management system, the solution to set up the visualized workflow modelling system based on B/S structure is put forward, which conforms to the relevant specifications o... According to the necessity of flexible workflow management system, the solution to set up the visualized workflow modelling system based on B/S structure is put forward, which conforms to the relevant specifications of WfMC and the workflow process definition meta-model. The design for system structure is presented in detail, and the key technologies for system implementation are also introduced. Additionally, an example is illustrated to demonstrate the validity of system. 展开更多
关键词 work flow work flow modeling system XPDL parsing.
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Provenance and salt structures of gypsum formations in Pb-Zn ore-bearing Lanping basin,Southwest China 被引量:1
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作者 ZHANG Zhi-bo ZHU Zhi-jun +4 位作者 LI Huan JIANG Wei-cheng WANG Wen-feng XU Ying LI Li-rong 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第6期1828-1845,共18页
Large-scale gypsum rocks associated with world-class Pb-Zn ore formations are widely distributed in the Lanping Basin,Sowthwest China.Geochemical studies alongside field investigations were conducted in this study to ... Large-scale gypsum rocks associated with world-class Pb-Zn ore formations are widely distributed in the Lanping Basin,Sowthwest China.Geochemical studies alongside field investigations were conducted in this study to determine the source and evolutionary processes of the gypsum rocks in this area.The gypsum sequences in the Lanping Basin developed in two formations:the Triassic Sanhedong Formation and the Paleogene Yunlong Formation.The gypsum hosted in the former displays a primary thick-banded structure withδ34SV-CDT values in the range of 14.5‰−14.8‰.Combined with the 87Sr/86Sr values(0.707737−0.707783)of limestone,it can be suggested that the Sanhedong Formation is of marine origin.In contrast,the gypsum from the Paleogene Yunlong Formation is characterized by the dome,bead and diapiric salt structures,wider range of both 87Sr/86Sr(0.707695−0.708629)andδ34SV-CDT values(9.6‰−17‰),thus indicating a marine source but with the input of continental materials.The initial layered salt formations were formed by chemical deposition in a basin and were later intensely deformed by collisional orogeny during the Himalaya period.As a result,variable salt structures were formed.We hereby propose an evolutionary model to elucidate the genesis of the gypsum formations in the Lanping Basin. 展开更多
关键词 Lanping basin GYPSUM marine sediment Sr–S isotopes salt structure
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