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81.
KOU Linlin DONG Xiaopeng LI Zhenhong CUI Jiawei MA Zhaoying LI Hailong 《《地质学报》英文版》2022,96(6):1917-1931
Daluo Mountains lie at front of the arcuate tectonic belt at the northeastern margin of the Tibetan Plateau, and are the landform boundary zone between the active Tibetan Plateau and the stable North China Craton. Studying of the late Cenozoic uplift evolution of Daluo Mountains is important for understanding the expansion mechanism of the northeastern margin of the Tibetan Plateau and its influence on the western North China Craton. In this study, the late Cenozoic uplift of Daluo Mountains is constructed from the development of the late Cenozoic alluvial fan around Daluo Mountains. The entire sedimentary sequence and framework of the fan was revealed by the newly obtained drilling core data. The cosmogenic nuclide, optically stimulated luminescence, and detrital zircon U-Pb dating results provide new evidences for discussion about the initial timing of the late Cenozoic uplift of Daluo Mountains and the key stages of uplift during the Pleistocene. The late Cenozoic alluvial fan at front of Daluo Mountains overlies a set of fluvial-facies strata; therefore, development of the alluvial-fan marks the start of late Cenozoic uplift of Daluo Mountains. The timing of this event can be constrained to ~4.64 Ma. Two extensive gravel layers (dated to ca. 0.76–0.6 Ma and ~0.05 Ma) developed during the Pleistocene, indicating two episodes of considerable uplift. This study provides a new time scale for the uplift and expansion of the arcuate tectonic belt at the northeastern margin of the Tibetan Plateau. 相似文献
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83.
YU Yang YE Qin ZHANG Kexin HE Weihong SONG Bowen XU Yadong KOU Xiaohu WANG Jiaxuan YANG Fengli 《《地质学报》英文版》2020,94(4):942-971
The Cryogenian is a critical period in the history of the Earth. It is marked by multiple extreme climate changes that caused alternating global glacial and interglacial intervals. These dramatically changed the sedimentary system, and metal ores and source rocks distributed widely during this period. Therefore, studying the Cryogenian stratigraphic framework and sedimentary basins is important to improve the stratigraphic resolution for metal mineral and hydrocarbon prospecting and exploration in China. This review paper firstly divides three tectonic-stratigraphic regions in China in the Cryogenian, including the tectonic-stratigraphic regions of Great South China, Xingmeng-Tarim, and North China. Secondly, geochronologic data and geological records are combined to clearly depict the Cryogenian sedimentary sequence of continental blocks and micro-continental blocks in different tectonic-stratigraphic regions. The results were used to propose a new comparison scheme of stratigraphy for the Cryogenian in China. Finally, according to differences of sedimentary evolution and tectonic evolvement, sedimentary basins and their lithofacies paleogeography are identified and summarized, respectively. 相似文献
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目前三峡水库区地质灾害治理正大规模地分期实施,监理作为治理工程参建的重要一方,如何根据监理理论采取相应的手段及措施,发挥监理工程师对工程“质量、进度、投资”3大目标的控制作用,从而使地质灾害治理工程取得良好的社会效益和经济效益,是值得探讨的重要课题。文章结合三峡水库区Ⅱ期地质灾害治理工程监理实践经验,就监理在治理工程中的控制作用分别从“质量、进度、投资”等方面进行了较详细地探讨。最后指出,与其它建设工程一样,监理在地质灾害治理工程中发挥着其他任何一方不可替代的作用。同时提出地质灾害治理工程中尚存在“监理取费偏低,监理人员的专业配置不合理,未对监理人员针对地质灾害工程的特点专门培训”等急需解决的问题。 相似文献
86.
深埋隧洞围岩分类方法--JPQ系统 总被引:2,自引:0,他引:2
本文以某深埋隧洞围岩分类为例、以著名的巴顿岩体质量分类Q系统为基础,建立了高地应力、高外水压力条件下的围岩分类方法--JPQ系统,经验证该方法在某深埋隧洞围岩分类中适用性好,并可推广使用. 相似文献
87.
KOU Long-jiang LI Hai-peng HU Yan-fei College of GeoExploration Science Technology Jilin University Changchun China 《吉林大学学报(地球科学版)》2006,(Z2)
鄂霍茨克海是西太平洋沿岸最北的边缘海,库页盆地是研究该边缘海地质问题最好的窗口.在已有的工作基础上,分析了库页盆地的地球物理场特征;详细讨论了库页盆地的沉积特点、深部结构和地质特征;并对库页盆地地质演化进行了初步的探讨.对库页盆地的研究结果,将对鄂霍茨克海以及中国边缘海盆有很好的帮助和借鉴作用。 相似文献
88.
榆神低硫煤中硫含量特征及成因探讨 总被引:5,自引:0,他引:5
陕北侏罗纪煤田榆神矿区煤大部分属于特低硫、低硫煤,硫的赋存形式以硫化物硫和有机硫为主。本文论述了榆神侏罗纪煤中硫含量特征及硫的来源、形成及沉积环境对低硫煤形成的控制作用。 相似文献
89.
路网密度的研究是实施“一带一路”愿景之互联互通倡议的基础工作。“一带一路”顺应了世界经济全球化、一体化、多极化、信息化的趋势,牵连着蓬勃发展的亚太和发达的欧洲经济圈,带动中间国家的经济发展。在新形势下,如何通过交通基础设施建设推进丝绸之路经济带沿线区域间的互联互通、促进区域合作和经济发展,具有重要的现实意义。本文利用自发地理信息数据——OpenStreetMap(OSM)道路网数据,运用地理信息系统(GIS)空间分析技术,探究了“一带一路”陆路经济带辐射区域亚欧大陆的路网络密度和通行能力的空间分布格局,并分析了六大经济走廊节点城市的公路可达性空间格局。结果表明:“一带一路”陆路经济带的交通基础设施的发展存在着不平衡现象;路网密度和通行能力均呈现沿海高内陆低的空间格局;中亚、西亚地区和中南半岛地区成为道路水平落后带,限制了丝绸之路经济带资源整合与贸易畅通,建议在建设新跨国公路铁路同时,对原有老旧道路进行加宽加固等升级改造;全区域道路等级级配不合理;节点城市可达性具有明显的分异状况,六大经济走廊中83%的区域可达性在10 h以内。研究产出亚欧大陆1 km分辨率路网密度和通行能力数据集,发现了“一带一路”陆路经济带道路水平的薄弱区域,为“一带一路”陆路经济带的交通基础设施建设以及进一步的道路网研究提供了基础数据。 相似文献
90.
The Multiple Column Platform (MCP) semi-submersible is a newly proposed concept, which differs from the conventional semi-submersibles, featuring centre column and middle pontoon. It is paramount to ensure its structural reliability and safe operation at sea, and a rigorous investigation is conducted to examine the hydrodynamic and structural performance for the novel structure concept. In this paper, the numerical and experimental studies on the hydrodynamic performance of MCP are performed. Numerical simulations are conducted in both the frequency and time domains based on 3D potential theory. The numerical models are validated by experimental measurements obtained from extensive sets of model tests under both regular wave and irregular wave conditions. Moreover, a comparative study on MCP and two conventional semi-submersibles are carried out using numerical simulation. Specifically, the hydrodynamic characteristics, including hydrodynamic coefficients, natural periods and motion response amplitude operators (RAOs), mooring line tension are fully examined. The present study proves the feasibility of the novel MCP and demonstrates the potential possibility of optimization in the future study. 相似文献