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1.
郑州-兰考区域性隐伏断裂的发现及其意义   总被引:1,自引:0,他引:1  
 黄河下游郑州京广铁桥—兰考段河道穿行于华北平原济源—开封凹陷,南邻太康隆起。该河段为著名的地上悬河,属典型的游荡型河床,河流地质作用以强烈侧蚀南岸为特征。遥感、物探综合解译首次发现在河道南岸存在一东西向郑州—兰考区域性隐伏深大断裂带,该断裂带的发现,从河流地质作用特征与基底新构造活动关系方面解释了该段黄河发生、发展和演化机理,解释了河床“小尺度游荡,大尺度呈直线状延伸” 的河道地貌特征和“河流强烈侧蚀南岸”的河流地质作用特征,对黄河下游河道防洪、治理具有重要意义。  相似文献   

2.
The mapability of Landsat images has opened up a new potentiality for study of channel pattern changes which was earlier not so easy due to nonavailability of suitable evidences at different timespans. Middle Ganga plain covering largely the northern part of Bihar and parts of eastern Uttar Pradesh is in a slate of perpetual flux due to large scale channel migration and avulsion resulting in devastating floods. Mosaic of three Landsat images has helped to study the channel changes which have occurred since 1935. The course of the river Ganga has beeh digitised along a basal line and two dimensional coordinates are taken at as many as more than fifty sample points for studying the magnitude and direction of channel changes during 1935–1975 period. The analysis shows that the main multiple channel river Ganga is under the huge hydrostatic thrust to be shifted towards south of its basin annually at a very high rate of 100 Meter per year all along the course except at its upstream near Ghazipur and at Monghyr where the shifting is towards north. The northward bend at Monghyr may be due to the presence of the Precambrian outliers here. For the multi-and single channelld tributaries of Ganga in channel behaviour is mainly in three directions—the lower water channels in the floodplain of Ganga are shifting to the south in conformity with that of their parent stream, the tributaries in Gogra-Gandak doab are shifting towards east but the shifting of the Kosi-Mahananda group of tributaries in the eastern part of the basin is towards west These channel pattern changes thus known at the interregional scale from the Landsat images may further be integrated with the study in hydrogeomorphology and their pertinent environmental impact.  相似文献   

3.
利用长江三角洲区域内19个GPS连续运行参考站2007~2013年间的观测数据,计算得到了该区域ITRF2005参考框架下的三维速度场、应变参数及区域参考框架下的速度场。结果表明,在ITRF2005框架下,水平方向平均速率为33.97 mm/a,优势方向为NE 111.5°;相对于欧亚板块的水平方向平均速率为9.36 mm/a,优势方向为NE 85.6°;高程方向以沉降为主,最大沉降速率为15.22 mm/a,平均沉降速率为4.7 mm/a;该区域块体以N 29.4° E的拉张为主,达到2.4×10-9/a,同时兼有N 119.4° E的挤压,达到1.3×10-9/a。  相似文献   

4.
本文通过对1992—2013年全国夜间灯光数据的校正和处理,获得全国及流域夜间灯光数据影像,进行经济空间聚合分析,以及与相关因子进行对比分析。研究结果表明:经济空间聚合高的区域分布在黄河河道附近,从黄河上游到下游,热力强度逐渐增强,并且以省会城市为核心区向外扩散,即呈现为在旧聚合点聚合度加剧的情况下,聚合区域有向周边分散的趋势;夜间灯光数据的变化趋势与GDP的变化趋势具有一定的相似性,并且与城镇化率、人口数量、第三产比例、人均公园绿地面积、流域发展指数(BDI)具有一定的相关性;流域9省(自治区)的夜间灯光数据整体变化趋势与全国灯光数据的变化趋势基本一致,呈稳定上升的趋势,但整体值均低于全国的夜间灯光数据,并且差距有所扩大,黄河流域高质量发展迫在眉睫。  相似文献   

5.
The Alaknanda River is the most significant parental river of Ganga and forms an 11.5 km long and 2.5 km wide valley, locally known as the Srinagar Valley. The purpose of the present study is to highlight the recent landform changes in the Alaknanda channel course after the Kedarnath disaster, 2013. The Kedarnath flood completely changed the channel morphology of the Alaknanda river. The river changed its course at Srikot, SSB and Sriyantra Tapu with lower terraces being silted by sands at Ranihat, SSB, Bhaktiyana and Sriyantra Tapu. A new depositional terrace also formed opposite to Sriyantra Tapu. New lateral channel bars, braided channels, back swamp, rapids, pools and river souls were identified in the channel course of the river. Shifting of the channel course at Chauras still remains a serious problem for the Garhwal University Chauras Campus. About 2–5 m silt was deposited on the lower terrace at SSB, and ITI. The Srikot river bed was appended to 4.60 m. Shifting of channel course remains a serious threat to the Srinagar valley. Urbanization, sand and boulders mining, construction of dam, hydrological canal, road and settlements are the prominent example of anthropogenic activities which affect the shifting channel.  相似文献   

6.
在收集地理、地质及水文等资料并对其进行详细整理分析的基础上,利用多时相卫星数据和航片,在相应数字图像处理软件 的支持下,对草尾河进行系统的遥感地质解译,并从地学和水动力学两方面研究了草尾河航道灵官嘴“跌水”形成的原因,预测了发 展演化趋势,为草尾河的航道疏浚提供参考资料。  相似文献   

7.
The Burhi‐Gandak river is one of the major tributaries of the Ganga River in the middle Ganga basin. The river is i known to have an oscillatory character and has changed its course in Recent times. In the present study, a variety of remote sensing data combined with surface and subsurface data have been used to delineate the fluvial palaeofeatures of this river. The palaeofeatures of the Burhi‐Gandak indicate that the river has shifted from N to S over a distance of 30 km. Further, its is observed that Burhi‐Gandak river had a larger channel width and higher discharge on earlier times and was very active. On detailed examination, a past link between the now northerly flowing Baghmati and Burhi‐Gandak rivers is detected. Based on the above features, three distinct stages of migration of the river have been identified and a summary of fluvial palaeohistory is presented.  相似文献   

8.
平飞模式双站SAR的改进CS成像算法   总被引:1,自引:0,他引:1  
本文针对机载双站SAR收、发系统分置的特点,首先建立了平飞模式双站SAR的回波信号模型,然后分析双站平飞正侧视下系统几何特点、距离徙动和距离徙动差以及距离多谱勒域距离向调频率的变化情况,并提出距离徙动差校正因子表达式和RD域距离向调频率的等效式,在此基础上结合单站的CS算法给出了双站平飞模式下的成像算法流程。最后通过实验仿真验证了本算法的正确性和可行性。  相似文献   

9.
全极化微波辐射计对环境参数敏感性分析   总被引:2,自引:0,他引:2  
王蕊  严卫  史顺文  陆文 《遥感学报》2015,19(3):375-390
为衡量全极化微波辐射计各通道对不同环境参数的探测能力,在构建全极化微波辐射传输正演模型的基础上,采用敏感性分析的方法,在固定背景场条件下,对全极化微波辐射计不同频率、各极化通道亮温对海面风速、海面风向、海面温度、大气水汽含量和云中液态水含量等重要环境参数的敏感度进行了分析和量化计算,对正演模型仿真亮温、星载全极化微波辐射计Wind Sat实测亮温相对于真实背景场参数、NCEP分析场资料和TAO/TRITON浮标实测海面风场数据的敏感性进行了分析。分析结果验证了全极化微波辐射计对海面风场的观测能力,衡量了上述重要环境参数对星载全极化微波辐射计各通道的单独影响程度,为中国自主研制全极化微波辐射计时通道指标设计、环境参数反演通道选取及算法提供支持。  相似文献   

10.
通过对航空立体像对及其边缘影像的分析,提出了一种新的航空影像初始视差的确定方法。试验表明,该算法能准确地确定纹理单一、影像对比度小的航空立体影像对的初始视差,可明显提高影像匹配的精度和可靠性。  相似文献   

11.
针对导航干扰信号测向初始相位估计难度大导致空间谱测向精度低、误差大的问题,提出了一种以经典多重信号分类(MUSIC)算法为基础的“少通道准校正空间谱测向方案”. 该方案是在每个通道内加入校准源,从而获得任意两个通道的初始相位差,减小了通道间的初始相位差对协方差矩阵计算的影响,实现空间谱测向的目的. 将所提的方案应用于五阵元三通道测向天线并在试验场地进行测试,实验结果表明:该方法能够解决复杂场景下单信号、双信号的测向,在低信噪比(SNR)的情况下,测向误差仍能保持在3.5°左右,测向精度较高,测向结果与全通道的测向结果基本一致.   相似文献   

12.
孟万忠 《测绘科学》2011,36(2):73-75
潇河是汾河的第二大支流,清代河道变迁频繁.本文利用清代山西地方志中的舆地图和现代空间数据,结合历史文献记载与实地考察,研究了潇河河道变迁最为剧烈的时期--清代近300年间的变迁过程,复原了不同时段的面貌,并对变迁原因进行了分析.认为在气候变干的大背景下,河道变迁的原因主要有两个:一是潇河及其支流泥沙含量大,造成旧河道的...  相似文献   

13.
现如今单波束测深系统及多波束测深系统已经在长江河道水下地形测绘中广泛应用,人们对于内河航道水下地形数据的精度要求也越来越高,声惯一体单波束测深系统很好地解决了传统单波束测深精度不高及多波束测深系统安装操作复杂且对测量水域条件要求较高等问题。本文针对声惯一体单波束测深系统在长江河道勘测中的实际应用情况,与传统单波束及多波束测量数据进行对比分析,结果表明声惯一体单波束测深系统能够很好地满足长江河道高精度测量的需求。  相似文献   

14.
在长江干线数字航道、无锡感知航道、长三角船联网及国外莱茵河航道RIS、密西西比河航道IWS/WIN等典型案例分析的基础上,按照内河数字航道的结构层次,从航道要素监测、航道数据、航道维护管理以及航道信息公共服务等4个方面全面归纳总结了技术研发进展情况,涵盖了关键技术、模型方法、协议标准、装备软件等内容,简要阐述了主要技术成果在长江干线、西江干线、京杭大运河等国家高等级航道网规划、建设、维护、管理、服务中的应用情况。从有序推进内河数字航道发展、对接内河水运转型升级需求的角度,指出了内河数字航道技术发展的总体趋势,并运用缺口分析法,找出了航道感知层、航道数据层、航道维护管理层、航道信息公共服务层等4个层次的技术瓶颈。本文的内容可为我国内河数字航道规划、建设与运行维护的技术选型及内河数字航道技术研发方向的选定提供借鉴。  相似文献   

15.
局部曲面正切曲率与流线曲率的水流路径算法   总被引:1,自引:0,他引:1  
在局部特殊地形如细窄的沟渠等地带,水流方向可能是惟一的,即当前点的水应全部流入下游惟一的格网点,此时若采用多流向算法不仅会导致水流方向产生较大误差,而且可能影响区域汇水面积的精确计算。为解决此问题,本文提出了一种水流路径算法,该算法通过以各格网点为中心建立3×3窗口范围内的局部趋势面,利用该点在局部趋势面中的正切曲率和流线曲率选取合适的单流向或多流向算法来确定并计算该点的水流流向及流量分配比例。最后通过实例证明了该方法在水流累积量计算中的良好效果,并在一定程度上为格网DEM沟谷段和分水线段的提取奠定了基础。  相似文献   

16.
基于DEM的平缓地区水系提取和流域分割的流向算法分析   总被引:3,自引:0,他引:3  
本文以地势较为平坦的秦淮河流域为实验样区,以高精度DEM(5m分辨率)和地形图水系为基础数据,对比分析了单流向算法(D8算法)、多流向算法(Dinf法)以及添加数字化河道信息后的单流向算法(AgreeD8算法)3种算法下水系提取和流域分割的结果。实验结果表明,提取得到的水系更逼近于实际河网,该算法既有效提高了水系提取和流域分割的精度,又保留了D8算法模型简单、稳定性强、运行效率高等优点。  相似文献   

17.
遥感技术在黄河流域治理开发规划中的应用   总被引:1,自引:0,他引:1  
本文简要介绍应用遥感技术进行黄河流域水利工程的地区稳定性分析、土地利用及水土保持 调查、河道变迁与河口演变以及影像地图编绘等方面的研究成果。  相似文献   

18.
河槽边坡地形的观测是河流边坡侵蚀和稳定性研究的基础。2016年洪季,利用三维激光扫描仪、多波束测深系统、RTK、差分GPS等仪器组成的多模态传感器系统,对长江下游铜陵段窝崩边坡和马鞍山段侵蚀型河漫滩边坡进行了联合地貌测量,对边坡陆上、水下高精度三维地形点云数据进行了融合研究,成功实现了边坡陆上水下三维地形的一体化和可视化。结果表明,多模态联合测量手段及三维点云融合方法能够获取较高分辨率的河流边坡陆上与水下一体化三维地貌模型,利用该模型可对边坡整体地貌特征进行定量计算分析,实现对河流险段的监测与稳定性评估,具有一定的工程意义。  相似文献   

19.
基于DEM的含油气盆地油气运移路径模拟   总被引:4,自引:0,他引:4  
以GIS的栅格数据结构为基础,按照油气运移的机理.借鉴地表水流向分析的GIS建模方法,构建了在GIS支持下开展油气运移路径模拟的详细算法,提出了基于DEM的油气运移路径模拟的基本流程。以我国北方某盆地为例,成功地模拟了该盆地深层天然气的运移路径。  相似文献   

20.
Water and suspended sediment fluxes are considered during the period 2000–2008 in a region including the full Amazon River from the confluence of the Negro River to Santarém, the end part of the Solimões River, and the lower part of the Madeira River. Three types of data are used: water discharge estimated from field measurements, and suspended sediment obtained from field measurements and derived from MODIS satellite data. A generalized least square method including a propagating term is developed in order to propagate the signal upward and downward the river. The approach is introduced and tested. Several experiments are considered in order, first, to estimate the ability to propagate the signal from stations located before the confluences of Negro and Madeira Rivers to stations located on the Amazon River; second to investigate the possibility to propagate the signal along the Amazon River which dynamics is coupled with floodplains dynamics; and third to produce optimal solutions of water and sediment fluxes. For each experiment, the influence of field and satellite data is compared. The approach is efficient in the upper part of the region of study where the Solimões, the Negro and the Madeira Rivers meet and fails in the lower part of the region where interactions between Amazon River and floodplains play an important role on the fluxes’ dynamics. The optimal experiment includes in situ and satellite data from all the stations available and is used to analyse the recent evolution of suspended sediment flux along the Amazon River and its interaction with the large coupled floodplains. A high accumulation rate is observed during the 2000–2002 period, followed by decreasing rates until 2005 and by increasing values in 2006 and 2007. Our results suggest that floodplains extending along a river reach of 390 km-long between Itacoatiara and Óbidos trap about 15% of the suspended sediment flux passing at Óbidos. The simulated deposition rate is of about 0.3 Mt km−1 yr−1 corresponding to an accretion rate of about 27 mm yr−1.  相似文献   

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