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RL3(t),Responsible for Leaf Shape Formation,Delimited to a 46-kb DNA Fragment in Rice
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作者 GUO Min LI Rong-de +6 位作者 YAO Jian ZHU Juan FAN Xiang-yun WANG Wei TANG Shu-zhu GU Ming-hong YAN Chang-jie 《Rice science》 SCIE CSCD 2015年第1期44-48,共5页
Two mutants with rolled leaves, temporally designated as rl3(t)-I and rl3(t)-2, were served for exploring the mechanism underlying the rolled leaf characteristic. Except for having typical rolled leaves, the plant... Two mutants with rolled leaves, temporally designated as rl3(t)-I and rl3(t)-2, were served for exploring the mechanism underlying the rolled leaf characteristic. Except for having typical rolled leaves, the plant heights and panicle lengths of rl3(t)-1 and rl3(t)-2 significantly decreased, and the seed-setting rate also decreased when compared with wild type 93-11. Cytological analysis suggested that the rolled leaf phenotype might be caused by the changes of number and size of bulliform cells. Genetic analysis indicated rl3(t)-1 is allelic to rl3(t)-2, and controlled by a recessive gene. Gene mapping result indicated that RL3(t) gene resided in a 46-kb long region governed by the sequence tag site markers S3-39 and S3-36 on rice chromosome 3. The result provides an important clue for further cloning the RL3(t) and understanding the mechanism of rice leaf development. 展开更多
关键词 gene mapping leaf shape formation MUTANT RICE rolled leaf gene
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Formation Mechanism of Curved Martensite Structures in Cu-based Shape Memory Alloys 被引量:2
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作者 Yujun BAI, Qiquan SHI,Guili GENG, Dongsheng SUN and Xiufang BIAN (Institute of Materials Engineering, Shandong University of Technology, Jinan 250061, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第1期79-81,共3页
The curved martensite structures have been observed in CuZnAI-based shape memory alloys by both transmission electron microscope and optical microscope. It was found that the curved martensite structures observed in a... The curved martensite structures have been observed in CuZnAI-based shape memory alloys by both transmission electron microscope and optical microscope. It was found that the curved martensite structures observed in as-solution treated, as-aged and as-trained alloys usually occurred around dislocation tangles or precipitate, at the plate boundary or grain boundary, and when the growing plates collided with each other or alternate mutually. 展开更多
关键词 formation Mechanism of Curved Martensite Structures in Cu-based shape Memory Alloys CU
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Hydrothermal Formation of Lath-Shaped Trioctahedral Smectite with High Crystallinity
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作者 Hirohisa YAMADA Kenji TAMURA +1 位作者 Shingo YOKOYAMA Yujiro WATANABE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第2期290-295,共6页
Lath-shaped and highly crystalline trioctahedral smectites were synthesized under hydrothermal conditions. The quenched glasses with stoichiometrically dehydrated Na-smectite compositions were treated at (a) 500℃ a... Lath-shaped and highly crystalline trioctahedral smectites were synthesized under hydrothermal conditions. The quenched glasses with stoichiometrically dehydrated Na-smectite compositions were treated at (a) 500℃ and 100 MPa for 1 and 11 days; and (b) 300℃ and 100 MPa for 7 days. The crystallinity and particle size of products were dependent on the chemical composition of the starting glass, synthetic temperature and duration of hydrothermal treatment. The high structural ordering and large dimensions of the products were confirmed from the sharpness of XRD peaks; and hydration behavior under controlled relative humidity. Transmission electron microscopy was also performed for the characterization of the particle size of product. Particle sizes vary from ca. 10 nm to a few pm by changing the chemical compositions of the starting materials. The product with the highest structural ordering and largest dimension was obtained from Nao.33(Mg1.83Al0.67)Si4O11 glass treated at 500℃ and 100 MPa for 1 day. The obtained results also confirmed the metastability and compositional dependency in the formation of highly crystalline trioctahedral smectite at hydrothermal conditions. 展开更多
关键词 high crystallinity hydration behavior hydrothermal formation lath-shaped trioctahedral smectite
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Shape格式数字海图自动更新技术研究 被引量:8
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作者 陈子澎 彭认灿 +1 位作者 刘国辉 郭立新 《海洋测绘》 2006年第3期62-64,67,共4页
在分析了我国目前所生产的Shape格式矢量数字海图缺乏更新服务的基础上,就更新服务的技术方法及相关问题进行了深入的探讨研究,为以后的工程实现提供了一定的基础理论和技术方法支持。
关键词 数字海图 shape格式 逐期式更新 累积式更新
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基于GML从DXF文件到Shape文件格式转换的研究与开发 被引量:7
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作者 刘伟 张海荣 《测绘科学》 CSCD 北大核心 2007年第4期177-178,共2页
由于AutoCAD系统与GIS系统在数据结构上存在着较大的差异,这使得其数据往往不能很好地满足GIS的要求。本文在分析目前AutoCAD数据到GIS数据转换存在问题的基础上,利用GML提出一种新的数据格式转化方法,解决了GIS系统与AutoCAD系统之间... 由于AutoCAD系统与GIS系统在数据结构上存在着较大的差异,这使得其数据往往不能很好地满足GIS的要求。本文在分析目前AutoCAD数据到GIS数据转换存在问题的基础上,利用GML提出一种新的数据格式转化方法,解决了GIS系统与AutoCAD系统之间的数据共享问题。并通过实践证明,该方法可以真正实现数据的无损转换。 展开更多
关键词 GML DXF文件 shape文件 格式转换
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非对称中空环形聚能装药成型与侵彻特性影响因素分析
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作者 李召婷 王树有 +2 位作者 孙圣杰 蒋建伟 门建兵 《爆炸与冲击》 EI CAS 北大核心 2025年第1期41-50,共10页
为减弱中空环形聚能装药形成的中心侵彻体对后级结构的破坏作用,通过改变环锥罩的偏心距离和壁厚,调整了装药和药型罩的质量分布,使之形成准直环形射流,研究了炸高对环形射流侵彻威力的影响规律。数值模拟结果表明:内壳为铝合金时的中... 为减弱中空环形聚能装药形成的中心侵彻体对后级结构的破坏作用,通过改变环锥罩的偏心距离和壁厚,调整了装药和药型罩的质量分布,使之形成准直环形射流,研究了炸高对环形射流侵彻威力的影响规律。数值模拟结果表明:内壳为铝合金时的中心孔平均侵彻深度较内壳为钢时的平均侵彻深度低36.13%;非偏心环锥罩形成的射流存在径向偏移,侵彻能力较弱。当环锥罩顶向外侧偏移0.05d(d为环形装药厚度)时,射流准直性较好,环形射流侵彻深度较大;随着药型罩壁厚的增加,射流头部速度不断减小,当壁厚为0.045d时,偏心环锥罩形成的环形射流侵彻能力较强;环形射流侵彻深度对炸高较为敏感,在炸高为1.12d时,环形射流侵彻深度较大。针对非偏心环锥罩和偏心环锥罩两种药型罩结构开展的静破甲试验表明,环形射流侵彻深度和扩孔直径的试验结果与数值模拟结果误差小于12%,验证了数值模拟模型的可靠性。 展开更多
关键词 环形聚能装药 偏心药型罩 射流成型 射流侵彻
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基于组件技术的由VCT到Shape数据格式转换研究 被引量:3
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作者 刘小伟 高飞 +2 位作者 胡小华 沙海峰 骆旭佳 《城市勘测》 2009年第2期65-68,共4页
数据转换是国土资源信息化和数据共享迫切需要解决的问题。本文分析了土地利用矢量数据交换文件VCT和Shape两种数据格式的结构,研究了基于VC和MO组件的VCT到Shape的数据格式转换方法,并用高级编程语言进行了程序编写,完成了两种数据之... 数据转换是国土资源信息化和数据共享迫切需要解决的问题。本文分析了土地利用矢量数据交换文件VCT和Shape两种数据格式的结构,研究了基于VC和MO组件的VCT到Shape的数据格式转换方法,并用高级编程语言进行了程序编写,完成了两种数据之间的格式转换,从而使VCT文件可以更方便地应用在GIS系统中。 展开更多
关键词 GIS VCT shape 数据格式 数据转换
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DWG格式空间数据转换为SHAPE格式方法介绍
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作者 谢庆胜 刘世靖 陶崇福 《电脑知识与技术》 2012年第9期5955-5957,共3页
该文详细介绍了如何将DWG格式空间数据转换成SHAPE格式数据的方法和具体的转换步骤、为今后类似转换工作提供技术参考。
关键词 DWG shape 数据格式转换
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MapObjects组件中Shape格式到Vct格式的转化方法 被引量:6
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作者 陈文玲 高飞 +1 位作者 胡晓华 罗旭佳 《地理空间信息》 2009年第4期95-97,共3页
介绍了以VC++为程序开发平台,基于MapObjects地图组件,实现将shape文件格式转换成vct格式的方法,从而实现两种数据格式的共享,提高数据的利用率。
关键词 GIS MAPOBJECTS shape格式 vct格式
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Theoretical and numerical simulation study on jet formation and penetration of different liner structures driven by electromagnetic pressure 被引量:3
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作者 Jian-hao Dou Xin Jia +4 位作者 Zheng-xiang Huang Xiao-hui Gu Ying-min Zheng Bin Ma Qiang-qiang Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第3期846-858,共13页
The use of a shaped liner driven by electromagnetic force is a new means of forming jets. To study the mechanism of jet formation driven by electromagnetic force, we considered the current skin effect and the characte... The use of a shaped liner driven by electromagnetic force is a new means of forming jets. To study the mechanism of jet formation driven by electromagnetic force, we considered the current skin effect and the characteristics of electromagnetic loading and established a coupling model of "ElectriceMagnetic eForce" and the theoretical model of jet formation under electromagnetic force. The jet formation and penetration of conical and trumpet liners have been calculated. Then, a numerical simulation of liner collapse under electromagnetic force, jet generation, and the stretching motion were performed using an ANSYS multiphysics processor. The calculated jet velocity, jet shape, and depth of penetration were consistent with the experimental results, with a relative error of less than 10%. In addition, we calculated the jet formation of different curvature trumpet liners driven by the same loading condition and obtained the influence rule of the curvature of the liner on jet formation. Results show that the theoretical model and the ANSYS multiphysics numerical method can effectively calculate the jet formation of liners driven by electromagnetic force, and in a certain range, the greater the curvature of the liner is, the greater the jet velocity is. 展开更多
关键词 Electromagnetic field shaped charge jet formation Theoretical calculation Numerical simulation
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Bore-center annular shaped charges with different liner materials penetrating into steel targets 被引量:2
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作者 Wen-long Xu Cheng Wang +1 位作者 Jian-ming Yuan Tao Deng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期796-801,共6页
The bore-center annular shaped charge(BCASC)is a new type of shaped charge which can generate a larger-diameter hole in steel targets than classical shaped charges.In this paper,the influence of three liner materials,... The bore-center annular shaped charge(BCASC)is a new type of shaped charge which can generate a larger-diameter hole in steel targets than classical shaped charges.In this paper,the influence of three liner materials,i.e.molybdenum,nickel and copper,on BCASC formation and penetrating into steel targets was investigated by experiment and numerical simulation.The simulation results were well consistent with the experimental results.This study showed that,at 0.50D standoff distance,the axial velocity of the molybdenum projectile was lower than that of the nickel and copper projectiles.The nickel and copper projectiles had almost the same head velocity.The absolute values of the radial velocity of the molybdenum projectile head was lower than that of the nickel and copper projectiles.However,at 0.75D standoff distance,the absolute values of the radial velocity of the molybdenum projectile head became much greater than that of the nickel and copper projectile heads.The projectile formed by BCASC with the molybdenum liner had the highest penetration depth of 61.5 mm,which was 10.0%and 21.3%higher than that generated by the copper and nickel projectiles. 展开更多
关键词 ANNULAR shapeD CHARGE LINER material formation Numerical simulation
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Overdriven Detonation and Its Application in Shaped Charges 被引量:1
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作者 Tariq Hussain Yan Liu Fenglei Huang 《Journal of Beijing Institute of Technology》 EI CAS 2017年第1期9-15,共7页
Overdriven detonation(ODD)in high explosives can be generated by Mach reflection of conical detonation waves propagating quasi-steadily in a co-axial double layer cylindrical charge.The inner core of the charge cons... Overdriven detonation(ODD)in high explosives can be generated by Mach reflection of conical detonation waves propagating quasi-steadily in a co-axial double layer cylindrical charge.The inner core of the charge consists of lower detonation velocity explosive with higher detonation velocity explosive for the outer core.The calculated pressures and detonation velocities in the ODD regime are compared with available results in the literature.The application of this technique to design a double layer shaped charge(DLSC)is numerically studied.It was discovered that the use of lower density-lower detonation velocity explosive in the inner core of DLSC can also yield similar results to those obtained with high density lower detonation velocity explosive.By analyzing previous experimental results and comparing with present simulations,it is demonstrated that ordinary shaped charges have some advantages over DLSC under certain conditions. 展开更多
关键词 overdriven detonation double-layer shaped charge jet formation
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Leader trajectory planning method considering constraints of formation controller
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作者 YAO Dongdong WANG Xiaofang +1 位作者 LIN Hai WANG Zhuping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1294-1308,共15页
To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm i... To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm is introduced.Firstly,a formation controller based on prescribed performance theory is designed to control the transient and steady formation configuration,as well as the formation forming time,which not only can form the designated formation configuration but also can guarantee collision avoidance and terrain avoidance theoretically.Next,considering the constraints caused by formation controller on trajectory planning such as the safe distance,turn angle and step length,as well as the constraint of formation shape,a leader trajectory planning method based on sparse A^(*)algorithm is proposed.Simulation results show that the UAV formation can arrive at the destination safely with a short trajectory no matter keeping the formation or encountering formation transformation. 展开更多
关键词 trajectory planning formation control prescribed performance controller multiple constraints formation shape formation transformation
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Influence of Structure Parameters of Double-angle Liner on Jet Formation
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作者 陈闯 王晓鸣 +2 位作者 李文彬 李伟兵 陈奎 《Defence Technology(防务技术)》 SCIE EI CAS 2012年第4期206-210,共5页
By using LS-DYNA simulation software,the influences of some structure parameters,such as top cone angle,wall thickness,liner height and height ratio of top cone,of double-angle liner on the jet formation were studied ... By using LS-DYNA simulation software,the influences of some structure parameters,such as top cone angle,wall thickness,liner height and height ratio of top cone,of double-angle liner on the jet formation were studied respectively.Their influences on jet tip velocity,tail velocity and penetration depth were revealed.The simulation results show that the formation is better if the top cone angle is selected as 28°,the wall is 2.6mm,the liner height is 140mm,and the height ratio of top cone is 60%.In large stand-off distance,the jet has a higher tip velocity,and the tip does not break.With the stand-off distance of 8 times of the charge diameter,the experiment penetrating steel target was carried out.The experiment and simulation results are in good agreement. 展开更多
关键词 弹药 应用爆炸力学 一般性问题 理论研究
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Preparation and Characterization of Flowershaped CuO Nanostructures by Complex Precipitation Method
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作者 Yunling Zou Yan Li Xiaoxue Lian Dongmin An 《材料科学研究(中英文版)》 2014年第3期44-51,共8页
关键词 纳米结构 络合沉淀法 氧化铜 结构表征 场发射扫描电镜 透射电子显微镜 平均尺寸 X射线衍射
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基于Shape Theory和Flocking的多智能体编队机动控制
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作者 何嘉诚 姚其峰 +2 位作者 代小林 宫大为 孙旭红 《自动化与仪表》 2020年第5期26-30,共5页
多智能体编队机动控制技术是多智能体控制的一个重要子任务。该文提出了一种基于Shape Theory和Flocking的多智能体编队机动控制算法,该算法能够控制一组智能体在保持目标队形的情况下,顺利避开障碍物并到达目标位置。该算法根据可行路... 多智能体编队机动控制技术是多智能体控制的一个重要子任务。该文提出了一种基于Shape Theory和Flocking的多智能体编队机动控制算法,该算法能够控制一组智能体在保持目标队形的情况下,顺利避开障碍物并到达目标位置。该算法根据可行路径设置相应的路径点和限制区域,使用基于Shape Theory的编队队形控制算法在每个限制区域中计算出满足目标队形约束的目标编队,再使用Flocking算法使智能体依次奔向这些目标位置。最后,通过仿真实验验证了该算法的有效性。 展开更多
关键词 多智能体 编队机动控制 shape Theory Flocking算法
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Sequence Pair-Based Scatter Search Approach for Cell Formation and Layout Considering Unequal Machine Dimensions and Cell Input and Output Locations
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作者 郑永前 钱伟俊 《Journal of Donghua University(English Edition)》 EI CAS 2015年第5期816-824,共9页
In the purpose of dealing with the inconsistency of the machine dimensions in cell formation and layout problems,comprehensively taking into account such factors as alternative process routings, lot splitting, cell in... In the purpose of dealing with the inconsistency of the machine dimensions in cell formation and layout problems,comprehensively taking into account such factors as alternative process routings, lot splitting, cell input and output( I / O)locations,an integrated cell formation and layout model considering unequal machine dimensions is established which aims at minimizing intra-cell material handling cost,inter-cell material handling cost and cell expansion cost. A sequence pair-based scatter search algorithm is proposed which simultaneously adopts the roulette wheel selection operator as a subsets combination method to improve the quality of new solutions and the dynamic reference sets updating method to accelerate the convergence rate. Through the comparison of the results achieved by the proposed algorithm, Lingo and simulated annealing under different problem scales,the correctness of the model and the effectiveness of the algorithm are verified. 展开更多
关键词 CELL formation and layout MACHINE shape SEQUENCE PAIR SCATTER search
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药型罩形状对活性聚能侵彻体成型的影响
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作者 孙韬 袁盈 +3 位作者 郑元枫 余庆波 陈鹏万 王海福 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第4期327-335,共9页
结合理论与数值模拟,对3种不同形状药型罩活性聚能侵彻体的成型行为开展了研究.数值模拟结果表明,在聚能效应下,球缺罩和大锥角圆锥罩形成尾部带有碎片云的类杆状活性聚能侵彻体,而小锥角圆锥罩则形成活性射流.相比于活性射流,类杆状活... 结合理论与数值模拟,对3种不同形状药型罩活性聚能侵彻体的成型行为开展了研究.数值模拟结果表明,在聚能效应下,球缺罩和大锥角圆锥罩形成尾部带有碎片云的类杆状活性聚能侵彻体,而小锥角圆锥罩则形成活性射流.相比于活性射流,类杆状活性聚能侵彻体速度较低,但凝聚性较好.进一步结合活性材料反应动力学方程,对活性聚能侵彻体成型激活反应行为进行分析.分析结果表明:活性射流激活区位于杵体外壁、射流头部和轴线附近;随炸高增加,激活区内活性材料反应不断加剧,特别是射流头部和轴线附近材料的反应,将导致活性射流膨胀发散,不利于侵彻;而类杆状活性聚能侵彻体激活区域主要集中在尾部碎片区和杆尾中心部位,化学反应对其影响相对较小. 展开更多
关键词 活性材料 聚能装药 射流 药型罩 成型行为
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山东寒武系崮山组褶颊虫类三叶虫Jiulongshania acalla个体发育过程中的头盖形态变化及其生态学意义
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作者 秦树健 董琳 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期626-638,共13页
基于大量采自山东济南唐王寨剖面寒武系崮山组的阿克利九龙山虫Jiulongshania acalla Walcott,1905标本,用传统的形态测量方法和几何形态测量方法,对头盖形态特征进行度量和定量化分析,揭示其在个体发育过程中的形态变化特点。研究结果... 基于大量采自山东济南唐王寨剖面寒武系崮山组的阿克利九龙山虫Jiulongshania acalla Walcott,1905标本,用传统的形态测量方法和几何形态测量方法,对头盖形态特征进行度量和定量化分析,揭示其在个体发育过程中的形态变化特点。研究结果显示,在个体发育过程中,J.acalla鞍前区的生长速率最快,头盖宽度的生长速率最慢,头盖形态变化主要表现为头盖整体形态由半扁椭圆形向半长椭圆形转变,鞍前区的宽度逐渐增加。推测三叶虫外骨骼形态的变化,特别是头盖形态的变化,可能与三叶虫的取食方式有关;J.acalla头盖标本在个体发育过程中的形态变化,可能指示从幼虫到成虫取食方式的改变。 展开更多
关键词 Jiulongshania acalla 头盖形态变化 寒武系 崮山组 山东
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川中地区震旦系“葡萄花边”白云岩的形成时代与成因
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作者 倪智勇 赵建新 +5 位作者 俸月星 周玮 杨程宇 刘汇川 邵钢钢 罗冰 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第1期282-294,共13页
四川盆地震旦系灯影组是重要的油气勘探开发层系,复杂的成岩演化和多期流体活动导致多种类型的白云岩形成。揭示震旦系白云岩的形成时代和成因不仅可以为四川盆地震旦系下一步的油气勘探提供更加充实的科学依据,也可为理解全球大规模存... 四川盆地震旦系灯影组是重要的油气勘探开发层系,复杂的成岩演化和多期流体活动导致多种类型的白云岩形成。揭示震旦系白云岩的形成时代和成因不仅可以为四川盆地震旦系下一步的油气勘探提供更加充实的科学依据,也可为理解全球大规模存在前寒武纪白云岩的原因提供有益启示。本文针对川中地区震旦系灯影组“葡萄花边”白云岩的形成时代和成因进行了综合研究。岩相学研究表明,“葡萄花边”白云岩充填于藻白云岩的孔隙内,向内对称生长,结晶程度明显好于藻白云岩。在岩相学的基础上,利用激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)微区原位U-Pb定年确定其形成时代,研究结果表明:川中地区震旦系灯影组“葡萄花边”白云岩形成时代为530±12Ma~502±12Ma,略新于灯影组地层年代。结合微量元素分析以及碳-氧-锶同位素数据,对川中地区震旦系灯影组“葡萄花边”白云岩进行成因分析。结果表明,其稀土元素总量(∑REE)相对较低(0.680×10^(-6)~8.963×10^(-6)),δ13 C VPDB(-0.1‰~1.7‰)略低于与同时期海水沉积白云岩的碳同位素值,δ18 O VPDB(-2.3‰~1.4‰)略高于与同时期海水达到氧同位素平衡的白云岩氧同位素值,87 Sr/86 Sr值(0.70876~0.70909)基本落入同时期海水范围。稀土元素配分总体为水平的模式,所有样品表现出Ce负异常。表明其形成环境既非海水沉积环境,也不完全是表生大气水岩溶条件。综合上述特征,推断川中地区震旦系灯影组“葡萄花边”白云岩是在震旦纪末-寒武纪早期海平面高频低幅度波动这一背景下,灯影组地层多次暴露与淹没,形成岩溶裂缝和孔洞的同时在溶蚀空间内结晶形成。残留孔洞为其后流体活动、油气充注提供了储集空间。本研究为认识川中地区震旦系灯影组“葡萄花边”白云岩成因、震旦纪末-寒武纪早期水化学条件、及超深层油气勘探开发提供了有益参考。 展开更多
关键词 四川盆地 灯影组 “葡萄花边”白云岩 白云石U-Pb定年 REE-C-O-Sr地球化学
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