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51.
讨论华南黑水─泉州地学断面的重磁解释。在解释中除应用常规的2.5维重磁异常反演外,还采用等密度线算法构制梯度层密度模型,用于分辨地壳密度细结构,以及计算自由地幔而深度用于分析上地幔密度的横向不均匀性。重磁模拟结果揭示了10km深度内的上地壳构造以及地壳与上地幔密度的分布。提出华南造山带以低密度上地幔为特征,它可能与上地幔的改造有关;四川盆地具有较高的上地幔密度,为未经改造的原始地幔。扬子克拉通与华南造山带的分界线与上地幔密度的分界线一致。根据布格异常、地表岩石密度和地形资料的综合分析,圈定出反映内生成矿作用深部标志的密度倒转区,可作为进一步找矿的远景区。  相似文献   
52.
Ground deformation may be caused by crustal movement and non-crustal movement.The non-crustal movements include those caused by temperature,rainfall,ground water,etc.Deformation caused by crustal movement includes seismogenic deformation(that appearing in the process of earthquake preparation and that directly caused by the earthquake)and general tectonic activities.The key point in the study of the relationship between ground deformation and earthquakes is how to eliminate information of deformation caused by non-crustal movement and permanent(or slow)tectonic deformation in observed data.In this paper an analysis is made on the short leveling data recorded at Dahuichang Deformation-Observing Station,Beijing,for 22 years(1970-1991)by using the LMS algorithm method after lateral adaptive filtering of the modern digital signal processing technique.Eliminating the approximate annual variation in deformation caused by non-crustal movement such as temperature,rainfall,ground water,etc.,a unified standard is  相似文献   
53.
Ground-based measurements are essential for understanding alpine glacier dynamics,especially in remote regions where in-situ measurements are extremely limited.Prom 1 May to 22 July 2005(the spring-summer period),and from 2 October 2007 to 20 January 2008(the autumn-winter period),surface radiation as well as meteorological variables were measured over the accumulation zone on the East Rongbuk Glacier of Mt. Qomolangma/Everest at an elevation of 6560 m a.s.l.by using an automatic weather station(AWS).The...  相似文献   
54.
The paper has developed and proposed a synthesis analysis method based on the robust satellite data analysis technique(RST) to detect seismic anomalies within the bi-angular advanced along-track scanning radiometer(AATSR) gridded brightness temperature(BT)data based on spatial/temporal continuity analysis. The proposed methods have been applied to analyze the Yushu(Qinghai, China) earthquake occurred on 14 th April 2010,and a full AATSR data-set of 8 years data from March2003 to May 2010 with longitude from 91°E to 101°E and latitude from 28°N to 38°N has been analyzed. Combining with the tectonic explanation of spatial and temporal continuity of the abnormal phenomena, the analyzed results indicate that the infrared radiation anomalies detected by the AATSR BT data with nadir view appear and enhance gradually along with the development and occurring of the earthquake, especially along the Ganzi-Yushu fault, Nu River fault and Jiali-Chayu fault; more infrared anomalies along the earthquake fault zone(Lancangjiang fault and Ning Karma Monastery-Deqin fault) are detected using the proposed synthesis analysis method, which can also characterize the activity of seismic faults more precisely.  相似文献   
55.
MODIS在水文水资源中的应用与展望   总被引:21,自引:1,他引:21       下载免费PDF全文
MODIS是新一代遥感技术,其遥测数据与其他单独的遥感平台(如NOAA和Land Sat)所获得的数据相比,具有免费、较高时间分辨率(0.5d)、空间分辨率(250m)和光谱分辨率(波谱范围0.4~14μm,36个光谱通道)等优势和特点.详细介绍了国内外的研究现状,着重对MODIS在洪水过程和洪灾范围实时动态监测、冰川和积雪、降水、植被、土壤水分、蒸发、水文模型、水质等方面的应用和研究进展进行了评述,指出MODIS在水文水资源中具有广阔的应用前景.  相似文献   
56.
The Sea Level Anomaly-Torque (SLAT, relative to a reference location in the Pacific Ocean), which means the total torque of the gravity forces of sea waters with depths equal to the Sea Level Anomaly (SLA) in the tropical Pacific Ocean, is defined in this study. The time series of the SLAT from merged altimeter data (1993-2003) had a great meridional variation during the 1997-1998 El Nio event. By using historical upper layer temperature data (1955-2003) for the tropical Pacific Ocean, the tempera- ture-based SLAT is also calculated and the meridional variation can be found in the historical El Nio events (1955-2003), which suggests that the meridional shifts of the sea level anomaly are also intrinsic oscillating modes of the El Nio cycles like the zonal shifts.  相似文献   
57.
For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of the Mekong source water system, inaccessible environment and the varied technologies used by those explorers and scientists. The satellite remote sensing technology has been used to pinpoint the source of the Mekong, associated with the on-the-spot investigations made by the authors in June 1999 and September 2002. The actual length of the Mekong has also been calculated.  相似文献   
58.
59.
In this paper, we report the first wetland mapping of the entire China using Landsat enhanced thematic mapper plus (ETM+) data. These data were obtained from the Global Land Cover Facility at the University of Maryland spanning from 1999 to 2002. A total of 597 scenes of Landsat images were georeferenced and mosaiced. Manual image interpretation of satellite images was aided with elevation data, soil data, land cover/land use data and Google Earth. The minimum mapping unit is 10 pixel × 10 pixel, equivalent...  相似文献   
60.
基于Oralce Spatial的综合管线数据库设计   总被引:3,自引:0,他引:3  
在分析了原有地下管线数据存储方法的不足以及使用Oracle Spatial存储地理数据的优点的基础上,提出了基于Oralce Spatial的地下综合管线数据库的设计模型,并针对在Spatial中保存地图符号属性的不足,提出了改进方法。  相似文献   
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