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961.
各种环形构造反映原生地质作用及后期改造作用形成的地表形态,也是矿化的直接体现。描述、研究云南环形构造遥感影像特征,寻找其矿化规律,指出潜在找矿方向。  相似文献   
962.
在水色遥感中,光学浅水底部反射的贡献显著地改变了水体反射信号的强度与光谱分布,成为制约二类水体遥感反演精度的瓶颈问题之一.在分析光学浅水概念和内涵的基础上,从水底反射特性测量、水底二向反射特性(BRDF)与水底反射效应校正模型3个方面论述了国内外在水底反射校正研究方面的进展;指出了发展光学浅水区的提取算法、建立典型底质...  相似文献   
963.
四川省"5.12"地震影响区,诱发了大童滑坡、崩塌、泥石流等地质灾害,给人民生命财产造成了重大损失.震后要相当长的余震期,加之降雨大,地质灾害还有进一步恶化的趋势.运用地面调查方法很难满足要求,尤其是很难满足时效性,结合研究区地质背景特征和多源遥感数据解译结果,确定地质灾害评价的指标体系,综合运用数学方法、GIS技术,...  相似文献   
964.
The American physical oceanographer Henry Stommel and co-workers proposed “the perpetual salt fountain” and suggested the possibility of upwelling deep seawater without an energy source. In the open ocean, deep seawater containing rich nutrients becomes a source of primary production. Previously, we have tested Stommel's hypothesis by numerical simulations and in ocean experiments, and confirmed the upwelling of a perpetual salt fountain. In the present study, we conducted an open-ocean experiment in the Philippines Sea, and succeeded to demonstrate an increase in chlorophyll concentration. The chlorophyll concentration at the pipe outlet was much greater than that in the surrounding seawater. Satellite ocean-color image around the pipe was analyzed, and the signal of artificial upwelling is investigated. Composite analysis of satellite chlorophyll image indicates an increased surface chlorophyll distribution in the vicinity of pipe position, in which the increasing signal is much larger than the expected production based on nutrient supply. Although the problem must be further discussed, this increased signal is shown to be statistically significant. This mechanism may contribute to effective utilization of fishery resources in subtropical oligotrophic region.  相似文献   
965.
HY-1B卫星是我国第二颗自主海洋卫星,针对其搭载的4波段海岸带成像仪(CZI)获取的数据,设计并基于IDL语言开发了一个专用的可视化数据处理与应用系统.该系统以黄河口为重点研究区域,对部分算法进行了优化和适应性改造,具备HY-1BCZI数据导入、预处理、海岸带动态监测产品制作、产品输出、数据批处理等功能,并能够进行数...  相似文献   
966.
根据2007~2009年7~9月渔汛期间我国鲐鱼灯光围网在东海的生产数据,利用海表温、叶绿素浓度、悬浮物浓度和透明度等遥感水质数据,分别将作业网次比例和单网次产量(CPUE)作为适应性指数,利用算术平均数(AM)和几何平均数(GM)分别建立基于海表温、叶绿素浓度、悬浮物浓度和透明度的综合栖息地指数模型。结果表明,AM栖息地指数模型和GM栖息地指数模型拟合效果较好(P<0.01),在HSI大于0.5的海域,2007~2009年7~9月平均作业网次比例在65%以上,各月平均CPUE均高于19.82 t/net。研究认为,AM模型稍优于GM模型。利用2010年7~9月生产数据及遥感水质数据对AM模型进行验证,分析认为,87%以上的作业网次和产量分布在HSI高于0.5的海域,CPUE为14~17 t/net,且较稳定,波动较小。研究认为,基于遥感水质数据的AM栖息地指数模型能较好地预测东海鲐鱼渔场。  相似文献   
967.
 黄河银川平原段河道演变的遥感监测与研究   总被引:2,自引:0,他引:2  
 在遥感调查和监测的基础上,结合第四纪地质资料,对黄河银川平原段的河道演变过程进行了系统研究,对主要的河流改道原因进行了分析。研究表明: 黄河银川平原段在早更新世初期形成,此后,自西向东不断迁移; 在中晚更新世发展壮大,到全新世形成了银川平原的主体,并留下了明显的古河道遗迹; 到了现代,河道逐步变窄,向东迁移的趋势未变且速度依然很快。  相似文献   
968.
Apostolos A. Christou 《Icarus》2005,178(1):171-178
The upcoming crossing of the Sun and the Earth through the equatorial plane of the planet Uranus presents an opportunity to observe mutual eclipses and occultations of the uranian satellites. We present predictions for 321 such events from 2006 to 2010. 230 of these events are “nominal” i.e. they are predicted to occur based on the currently available ephemeris while a further 91 “grazing” events are allowable given the positional uncertainties of the satellites. Taking into account the statistical frequency of events that occur too close to the planet, during solar conjunction or are too “shallow” to observe, we conclude that about 150 events should be detectable from different longitudes around the world. We argue that a worldwide campaign of photometric observations of these events will yield, as in the case of the jovian and saturnian systems, high-precision astrometric information on the satellites toward improving their ephemerides as well as the system constants (satellite masses, uranian zonal harmonics, etc.). In addition, mathematical inversion of the lightcurves should permit, subject to the photometric quality and number of observed events, mapping of albedo variegations over the satellite hemispheres that were in darkness during the Voyager 2 encounter with the uranian system in 1985/1986.  相似文献   
969.
Louise Prockter  Paul Schenk 《Icarus》2005,177(2):305-326
Europa's Castalia Macula region was comprehensively imaged by the Galileo spacecraft on several orbits, at both local and regional resolutions and with different illumination geometries. Using these datasets we have mapped and identified the different geological units within the Castalia area, and derived digital elevation models (DEMs) of the topography within most of the Castalia Macula region. Using these data sets in combination allows us to map the geology and topography of this area in greater detail than perhaps any other site on Europa. Castalia Macula consists of unusually dark and reddish material, most of which is confined to a broad topographic depression 350 m deep located between two large uplifted domes 900 and 750 m high, to the north and south, respectively. The preservation of topography at the bottom of Castalia Macula indicates that dark material initially filled the depression to a certain depth but was subsequently removed via drainage, resulting in a dark stain up to the original equipotential surface. Superposition and topographic relationships suggest that the Castalia Macula plains deposit formed prior to uplift of both domes, and at least two distinct episodes of chaos formation have occurred near and on top of the northern dome. It appears that Castalia Macula is comparatively young and was active relatively recently, therefore it could provide an ideal place to sample material that has recently been erupted from the subsurface, and may have been in communication with Europa's ocean. These factors combine to make Castalia Macula a very attractive site for a future Europa lander.  相似文献   
970.
以遥感解译为主,配合野外调查,作者对沈阳地区的地貌类型进行了划分。沈阳地区地貌可划分为4种成因类型,14种形态类型,各种地貌类型具有明显的影象特征。通过航片系统解译,提高了各类地貌形态界线的圈定精度,建立了全区地貌的立体模式。  相似文献   
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