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Southeastern extension of the Red River fault zone (RRFZ) and its tectonic evolution significance in western South China Sea 总被引:3,自引:0,他引:3
LIU Baoming XIA Bin LI Xuxuan ZHANG Minqiang NIU Binhua ZHONG Lifeng JIN Qinghuan JI Shaocheng 《中国科学D辑(英文版)》2006,49(8):839-850
The tectonic evolution features in the western South China Sea (SCS) are directly related to the Tethys tectonic province. The Red River fault zone (RRFZ) comprises a large part of the Tethys tectonic province and is the boundary between the Europe Block and the India-Asia Block[1]. It serves as the contact between the uplift of the Qinghai-Tibet Plateau and the SCSopening. The RRFZ, which is an important dividing line in the geology of the SE Asia, is about 1000 km long in the co… 相似文献
944.
A study of interaction between surface water and groundwater using environmental isotope in Huaisha River basin 总被引:20,自引:0,他引:20
The surface water and groundwater are important components of water cycle, and the interaction between surface water and groundwater is the important part in water cycle research. As the effective tracers in water cycle research, environmental isotope and hydrochemistry can reveal the interrelationships between surface water and groundwater effectively. The study area is the Huaisha River basin, which is located in Huairou district, Beijing. The field surveying and sampling for spring, river and well water were finished in 2002 and 2003. The hydrogen and oxygen isotopes and water quality were measured at the laboratory. The spatial characteristics in isotope and evolution of water quality along river lines at the different area were analyzed. The altitude effect of oxygen isotope in springs was revealed, and then using this equation, theory foundation for deducing recharge source of spring was estimated. By applying the mass balance method, the annual mean groundwater recharge rate at the catchment was estimated. Based on the groundwater recharge analysis, combining the hydrogeological condition analysis, and comparing the rainfall-runoff coefficients from the 1960s to 1990s in the Huaisha River basin and those in the Chaobai River basin, part of the runoff in the Huaisha River basin is recharged outside of this basin, in other words, this basin is an un-enclosed basin. On the basis of synthetically analyses, combining the compositions of hydrogen and oxygen isotopes and hydrochemistry, geomorphology, geology, and watershed systems characteristics, the relative contributions between surface water and groundwater flow at the different areas at the catchments were evaluated, and the interaction between surface water and groundwater was re- vealed lastly. 相似文献
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移动GIS技术在地质灾害数据采集领域的应用研究 总被引:5,自引:1,他引:5
移动GIS技术基于PDA(掌上机)及WinCE作为软件运行的软硬件平台,掌上机具有进行野外数据采集的很多独特优势。将这种独特优势与传统数据采集技术相结合,现场采集地质灾害数据,并以数字化技术延伸至野外,从而可有效地解决目前地质灾害数据采集面临的反馈信息严重滞后,采集信息不完整,在数据采集手段上存在的记录内容随意、记录格式不规范及野外使用不方便等问题。该系统采用ESRI的ArcPad Application Builder二次开发软件,对ArcPad进行面向地质灾害数据采集领域的功能定制,使系统集成了GPS或手工定点的空间信息在基础地理底图的显示、地质灾害点属性信息通过友好的界面实现录入及数据的入库以及野外采集到的空间及属性信息与室内ArcGIS软件平台顺畅的数据交流功能,实现了利用移动GIS技术与地质灾害预警预报过程中地质灾害数据采集的全程数字化操作,并摸索了一套完成的工作流程。这种技术的采用有望对传统野外地质灾害数据采集手段带来质的突破。 相似文献
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藏北龙木错东部三岔口地区下奥陶统与泥盆系的不整合界面 总被引:7,自引:6,他引:7
在北羌塘三岔口一带采获丰富的腕足类:汉伯矮正形贝及比较种Nanorthis cf.hamburgensis(Walcott).建立了早奥陶世岩石地层单位--三岔口组,是羌塘地区目前有化石控制的最低层位.中、晚泥盆世拉竹龙组与下伏志留系、奥陶系不整合接触关系的进一步确定,证明了羌北-昌都板块与扬子板块的亲缘性,为羌北-昌都板块属性的确定提供了重要证据. 相似文献
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