956 resultados para Landsat satellites.


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Hydrological statistical data, remote sensing images, and bathymetric charts were used to study the recent evolution of the Huanghe (Yellow) River delta under human-induced interventions. It was clear that water and sediment discharge from the Huanghe River had dropped rapidly since 1970, particularly after 1986. The water and sediment discharges for the period of 1986-2000 were found to have been reduced to only 29.2% and 31.2% of those in the period of 1950-69. This was caused by human factors in the upper and middle reaches of the Huanghe River, including water diversion, damming and reservoir construction, and water and soil conservation. Based on the results from visual interpretation of processed Landsat (MSS or TMJETM+) images dated from 1976 to 2001 and two digital elevation models generated from bathymetric charts surveyed in 1976 and 1992, we found that human-induced reduction of water and sediment discharge led to coastline retrogradation, with the maximum mean recession rate of -0.51 km yr-1 over the period of 1976-98, and seabed erosion beyond the -20 m isobath between 1976 and 1992. Other impacts of human activities on the recent evolution of the Huanghe River delta, including tidal flats shrinking, artificial coastline increasing, land surface sinking and so on, were also analyzed. We found that: (i) the whole delta, including subaerial and subaqueous, has turned from a highly constructive period to a destructive phase; (ii) channelization and dredging were two of the main causes of delta destruction; (iii) land loss in the Huanghe River delta caused by submersion will be increased in the near future; (iv) the Huanghe River delta was becoming more fragile and susceptible to natural hazards.

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Near-space, defined as the altitude region between 20 and 100 km, offers many capabilities that are not accessible for low Earth-orbit (LEO) satellites or airplanes because it is above storm and not constrained by orbital mechanics and high fuel consumption. Hence, a high flying speed can be obtained for the maneuvering vehicles operating in near-space. This offers a promising solution to simultaneous high-resolution and wide-swath synthetic aperture radar (SAR) imaging. As such, one near-space wide-swath SAR imaging technique is presented in this letter. The system configuration, signal model, and imaging scheme are described. An example near-space SAR system is designed, and its imaging performance is analyzed. Simulation results show that near-space maneuvering vehicle SAR indeed seems to be a promising solution to wide-swath SAR imaging.

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Eddies are frequently observed in the northeastern South China Sea (SCS). However, there have been few studies on vertical structure and temporal-spatial evolution of these eddies. We analyzed the seasonal Luzon Warm Eddy (LWE) based on Argo float data and the merged data products of satellite altimeters of Topex/Poseidon, Jason-1 and European Research Satellites. The analysis shows that the LWE extends vertically to more than 500 m water depth, with a higher temperature anomaly of 5A degrees C and lower salinity anomaly of 0.5 near the thermocline. The current speeds of the LWE are stronger in its uppermost 200 m, with a maximum speed of 0.6 m/s. Sometimes the LWE incorporates mixed waters from the Kuroshio Current and the SCS, and thus has higher thermohaline characteristics than local marine waters. Time series of eddy kinematic parameters show that the radii and shape of the LWE vary during propagation, and its eddy kinetic energy follows a normal distribution. In addition, we used the empirical orthogonal function (EOF) here to analyze seasonal characteristics of the LWE. The results suggest that the LWE generally forms in July, intensifies in August and September, separates from the coast of Luzon in October and propagates westward, and weakens in December and disappears in February. The LWE's westward migration is approximately along 19A degrees N latitude from northwest of Luzon to southeast of Hainan, with a mean speed of 6.6 cm/s.

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Anti-cyclonic eddies northwest of Luzon of the Philippines in summer-fall are identified in the merged data products of satellite altimeters of Topex/Poseidon, Jason-1 and European Research Satellites. The generation and propagation of the anti-cyclonic eddies, which are confirmed by satellite ocean color data, are found to be a seasonal phenomenon that is phase-locked to the onset of the southwesterly monsoon and the relaxation of the cyclonic wind curl in the northeastern South China Sea. The eddies originate from northwest of Luzon in summer, move across the northeastern South China Sea to reach the China continental slope in fall, and propagate southwestward along the continental slope in fall-winter, inducing shelfbreak current variations in the western South China Sea in fall-winter. The anti-cyclonic eddy discovered by Li et al. (1998) in the northern South China Sea is found to originate from northwest of Luzon and carry primarily the South China Sea waters. It does not appear to be an eddy shed from the Kuroshio in the Luzon Strait area as alluded by Li et al. (1998) and others.

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本文以具有典型特征的苏北淤泥质潮滩海岸作为研究区,利用1975-2003年间14景覆盖该地区的Landsat和SPOT卫星影像作为主要数据源,结合地面调查和验证工作,在遥感影像处理和地理信息系统分析技术的支持下,对区内潮滩、岸线、水边线和盐沼植被等进行遥感解译,分析苏北辐射沙脊群和沿岸地貌的空间分布特征和动态演变趋势。研究结果表明:苏北辐射沙脊群海域的潮汐水位过程的不同步现象普遍存在,限制了常规遥感数据在苏北潮滩地貌研究中的适用范围和解译精度;在人工判别的辅助下,多光谱遥感的非监督分类方法可以有效解译淤泥质潮滩的水边线;利用修改型土壤调整植被指数(MSAVI)可以较好地提取潮滩上的盐沼植被信息;苏北沿岸潮滩的快速淤长促进了盐沼植被带向海侧快速扩展,近年来持续的潮滩围垦工程则不断从陆侧侵占盐沼植被带,使盐沼植被带宽度减小乃至消失;在大规模人类活动和自然条件的共同影响下,苏北辐射沙脊群海岸的岸线发育趋于平直化,无序的潮滩围垦项目使得可垦滩地资源被过度消耗;1975~2002年间,研究区北部和南部沿岸的高潮滩整体上处于淤长状态,中部沿岸潮滩和离岸沙洲高潮滩则被大面积侵蚀;1999年以来,研究区内低潮滩部位开始形成有序排列的滩面地物,并表现出逐年大面积蔓延的趋势,可能是滩涂紫菜养殖区扩展的结果。

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本文收集了三峡截流前后长江口海区1988-2007年间十二景landsat TM遥感影像并进行了表层悬浮泥沙含量的反演,定性的描述了长江口海区洪、枯季的表层悬沙扩散外界和高浑浊水域范围的变化趋势,分析了河流泥沙输移入海形态的变化特征及表层悬沙浓度的变化特征。 通过对2002-2004年在长江口滨外区表层悬浮体取样数据的实验室处理,揭示了三峡截流后表层悬沙的分布特征;通过多船同步定点观测捕捉到了长江口河口锋带的位置并分析了河口锋带的动力特征,结果表明:长江口河口锋位于(122o10′E,30o50′N)至(122o20′E,31o00′N)一线附近,在河口锋带位置有着较为强烈的河海相互作用,流速不符合典型的对数流速曲线,河水与海水的相互消长局限于海面以下5m的表层范围,在河口锋面区悬浮泥沙为泥沙流伏在海水之上输运。长江口悬沙体浓度由于三峡蓄水作用表现为下降趋势,悬浮体扩散范围相比截流前向口门后退,长江口滨外区羽状锋带随之向口门后退。 利用二维潮流数值模型较成功地模拟出了每个季度长江河口外的流场情况及河口锋带的发育情况,模拟表明:春、夏、秋三季河口锋带较易出现,且小潮期间发育最好。冬季长江河口海洋动力较强,易于发生海水入侵,尤其是北支;夏季是长江三角洲的主要建设期,锋带作用的存在使得泥沙大部分在锋带的内外区域沉积;春秋两季是平衡期;冬季主要是冲刷的时期。

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合成孔径雷达(SAR)是重要的微波传感器之一,在海洋遥感领域得到了广泛应用。浅海水下地形SAR探测是SAR海洋应用的重要部分之一,发展业务化水下地形SAR探测技术是水下地形SAR探测研究的最终目标。现有的水下地形SAR探测是基于单景SAR影像开展的,探测结果不能全面反映水下地形。因此,发展一种基于多源多时相SAR影像的水下地形反演方法是该研究方向的前沿问题。 本文基于水下地形SAR成像机制和袁业立(1997)导出的海波高频谱解析表达式,首次建立了基于多源多时相SAR影像的水下地形反演的同化模型与算法,并通过该模型在台湾浅滩水下地形SAR探测中的应用检验了该模型和算法的可行性。本文还开展了已有的浅海水下地形SAR探测技术(浅海水下地形单景SAR影像反演)在台湾浅滩水下地形探测中的应用研究,以及反演初始水深对水下地形SAR反演结果影响的研究。此外,本文还对中国近海水下地形SAR成像能力进行了分析。 在浅海水下地形SAR探测技术应用于台湾浅滩研究方面,基于7景SAR影像开展了台湾浅滩单景SAR影像反演计算,反演结果表明同一水下地形不同时相SAR影像反演结果不能全面反映真实地形特征。 在反演初始水深对水下地形SAR反演结果影响研究方面,通过不同初始水深条件下台湾浅滩水下地形SAR反演结果的比较分析,可以得出:初始水深影响水下地形反演结果的准确性,初始水深的选取需要较粗的实际水深的支持; 在多源多时相水下地形SAR反演同化模型研究方面, 建立了多源多时相水下地形SAR反演的同化模型与算法,通过基于多源多时相SAR影像的台湾浅滩五种不同情形水下地形反演计算,证明了多源多时相水下地形SAR反演同化模型和算法是可行的,并给出了基于多源多时相SAR影像的水下地形反演计算中SAR影像的选取原则。 在中国近海浅海水下地形SAR响应能力分析方面,基于对中国近海潮汐潮流状况、水下地形概况和已有中国近海SAR影像中水下地形特征等的分析,总结出中国近海适合开展浅海水下地形SAR探测的区域主要有:渤海海域、苏北近海海域、台湾海峡海域和南沙群岛海域。

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The VEGETATION (VGT) sensor in SPOT 4 has four spectral bands that are equivalent to Landsat Thematic Mapper (TM) bands (blue, red, near-infrared and mid-infrared spectral bands) and provides daily images of the global land surface at a 1-km spatial resolution. We propose a new index for identifying and mapping of snow ice cover, namely the Normalized Difference Snow/Ice Index (NDSII), which uses reflectance values of red and mid-infrared spectral bands of Landsat TM and VGT. For Landsat TM data, NDSII is calculated as NDSIITM =(TM3 -TM5)/(TM3 +TM5); for VGT data, NDSII is calculated as NDSIIVGT =(B2- MIR)/(B2 + MIR). As a case study we used a Landsat TM image that covers the eastern part of the Qilian mountain range in the Qinghai-Xizang (Tibetan) plateau of China. NDSIITM gave similar estimates of the area and spatial distribution of snow/ice cover to the Normalized Difference Snow Index (NDSI=(TM2-TM5)/(TM2+TM5)) which has been proposed by Hall et al. The results indicated that the VGT sensor might have the potential for operational monitoring and mapping of snow/ice cover from regional to global scales, when using NDSIIVGT.

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以3S技术为手段,研究了藏羚在青海最主要分布区曲麻莱、治多和可可西里境内藏羚生境状况及其坡度、道路、和居民点对藏羚生境的影响。通过野外考察基本掌握了藏羚的生境的基本特征,取得了考察路线附近区域内藏羚分布的GPS数据及其具有对应的数量、地形地貌、生境类型、人类活动状况等属性数据的藏羚分布点图层。对研究地区LANDSAT TM / ETM+ 5(红)、4(绿)、3(蓝)波段组合影像进行非监督分类,共分出水体和裸岩、沼泽地、沙地、砾石地、低草地、中草地和高草地7种生境类型,将藏羚生境适宜等级划分为不适宜、较差、适宜和非常适宜,其中适宜等级和非常适宜等级的生境类型为藏羚适宜的生境。 首先,将藏羚分布点图层分别和遥感影像假彩色合成图像、坡度图层、道路图层、居民点图层进行叠加分析、距离查询等分析了遥感影像非监督分类的判图依据,设立了坡度、道路、居民点对藏羚生境影响强度的评价原则。然后,通过对研究地区遥感影像进行非监督分类分析研究了藏羚不同适宜程度的生境面积。通过坡度分析和地图查询分析研究了坡度对藏羚生境的影响。通过缓冲区分析研究了道路和居民点对藏羚生境的影响。最后将坡度、道路和居民点三个因素结合起来通过地图综合查询分析研究了这三个因素对藏羚生境的综合影响,并给出了研究地区藏羚不同适宜等级的生境面积。 主要的研究结果和结论如下: 1、从不同类型生境在研究地区中所占比例的趋势上看,治多地区和曲麻莱地区的植被要明显优于可可西里地区,这与整个研究地区从西北到东南地势逐渐降低、水热条件逐渐变好的趋势相一致,至少可以说,从食物条件来看,治多地区和曲麻莱地区比可可西里地区更适于藏羚的栖息。 在曲麻莱地区藏羚的潜在生境面积共26861 km2,占该地区总面积的69%;在治多地区藏羚的潜在生境面积共21617 km2,占该地区总面积的68%;在可可西里地区藏羚的潜在生境面积共26398 km2,占该地区总面积的54%。 2、根据藏羚分布点图层与坡度分析图层的地图查询分析,把藏羚的生境按坡度分为2类,坡度小于等于30度时为适宜生境,坡度大于30度时为不适宜生境。将研究地区坡度栅格图像(grid文件)和非监督分类结果栅格图像(grid文件)进行地图查询分析,结果表明,在整个研究地区坡度大于30度的生境面积所占的比例不到总面积的3%,坡度影响下研究地区藏羚适宜栖息的生境面积变化不大。考虑到坡度的影响,曲麻莱、治多和可可西里适合藏羚栖息的面积分别为26663 km2(68%)、21187 km2(66%)和26350 km2(54%)。 3、根据最近原则连接藏羚分布点图层与道路图层空间数据,通过Distance综合查询分析,把道路对藏羚的影响程度划分为4个等级:距离道路0-1000m,强烈影响;距离道路1000-2000m,中度影响;距离道路2000-3000m,轻度影响;距离道3000m以外,无影响。然后在ArcView GIS 3.2a软件环境的支持下对研究地区的道路图层分别做距离道路为1000m、2000m和3000m的缓冲区分析研究,则曲麻莱、治多和可可西里地区藏羚生境受道路累计影响的面积及其分别占各研究地区总面积的比例分别为20215 km2(51.80%)、19480 km2(61%)和4437 km2(9 %)。考虑道路对藏羚生境的影响,在治多和曲麻莱地区,由于道路的影响将使得藏羚生境大面积丧失,生境高度破碎化。 4、根据最近原则连接藏羚分布点图层与居民点图层空间数据,通过Distance综合查询分析,把居民点对藏羚的影响程度划分为4个等级:距离居民点0-3000m,强烈影响;距离居民点3000-6000m,中度影响;距离居民点6000-9000m,轻度影响;距离居民点9000m以外,无影响。然后在ArcView GIS 3.2a软件环境的支持下对研究地区的居民点图层分别做距离居民点距离为3000m、6000m和9000m的缓冲区分析。曲麻莱、治多和可可西里地区藏羚生境受居民点影响的面积及其分别占总面积的比例分别为11282 km2(29%)、15258 km2(48%)和3846 km2(8%)。从居民点对藏羚生境的影响看,由于居民点的影响使得治多和曲麻莱地区,尤其是治多地区,藏羚生境大面积丧失,生境高度破碎化。 5、人类活动(主要是道路和居民点)对藏羚生境适宜生境面积的影响是研究中主要的内容,鉴于道路和居民点对藏羚生境影响的评价原则分类方法一致,我们把道路和居民点对藏羚的影响程度合并为4个等级(距离道路0-1000m内或距离居民点0-3000m内,强烈影响;距离道路1000-2000m内或距离居民点3000-6000m内,中度影响;距离道路2000-3000m内或距离居民点6000-9000m内,轻度影响;距离道路3000m以外或距离居民点9000m以外,无影响,对道路和居民点相应距离的缓冲区分析图层进行合并等操作,测定曲麻莱、治多和可可西里地区藏羚生境受人类活动影响的面积及其占总面积的比例分别为21595 km2(55%)、22271 km2(70%)和4775 km2(10%)。 在治多和曲麻莱地区,由于人类活动的影响使得藏羚生境大面积丧失,生境高度破碎化,尤其是治多地区,影响面积达将近70%。在可可西里地区,10%的影响面积虽然不是太大,但是近几年来由于各种形式的旅游日趋升温,尤其是青藏铁路建设开通,将增加道路对藏羚生境的影响程度。人类活动影响在研究地区分布极不平均,在曲麻莱的中东部、治多的东部以及可可西里的109国道附近人类活动影响的强度较大,在这些地区藏羚的生存条件恶劣,甚至部分地区已经不适合藏羚栖息了。 6、最后,基于研究地区的坡度grid图层、非监督分类grid图层以及不同程度人类活动影响的grid图层,对不同坡度、道路和居民影响的生境面积进行综合查询分析。把人类活动对藏羚生境的影响强度重新划分为如下3个等级,A、短距离影响,距离道路1000m或距离居民点3000m范围内的影响,也就是人类活动的强烈影响;B、中距离影响,距离道路2000m或距离居民点6000m范围内的影响,也就是人类活动的强烈影响和中度影响之和;C、长距离影响,距离道路3000m或距离居民点9000m范围内的影响,也就是人类活动的强烈影响、中度影响和轻度影响的总和。曲麻莱、治多和可可西里研究地区中坡度小于等于30度并且人类活动长距离范围影响下藏羚适合栖息的生境面积及占相应研究地区总面积的比例为12597 km2(32%)、6117km2(19%)和23564km2(48%)。 在研究地区,治多地区人类活动对藏羚生境适宜性的影响最为严重,其次为曲麻莱地区,而可可西里地区的人类活动影响较小。尤其是治多地区和曲麻莱地区,当人类活动的影响最大距离时,治多地区藏羚适宜生境面积竟然不到总面积的1/5,曲麻莱地区不到1/3。这两地区人类活动主要集中在东部,导致治多东部地区和曲麻莱中东部地区几乎没有藏羚分布。于是,由于人类活动的影响,使得拥有良好生境条件的治多和曲麻莱地区适合藏羚栖息的生境却较少,而生境条件相对较差的可可西里地区反而拥有相对较多的适合藏羚栖息的生境。

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The magnetosphere-ionosphere coupling is mainly manifested by the trans- porting processes of energy into the ionosphere , the energy is carried by solar wind and firstly accumulate at the magnetosphere, and the coupling processes also significantly include the interaction between the magnetosphere and ionosphere for mass and energy. At the quiet condition, energy is delivered by the large-scale convection of the geomagnetic field; the huge energy from solar wind bulk will be injected into and consumed at the near magnetosphere and ionosphere by the geomagnetic storm and substorm activities. Aurorae and FACs (Field-aligned currents) are the important phenomena in the coupling processes. In the present work, firstly, we analyze the activity characteristics of auroral precipitating particle, secondly, we study the distribution characters of large-scale field aligned currents (LS FACs) at storm-time using the observations from different satellites at different altitudes. Finally, we investigate the evolution of the geomagnetic field configuration at the nightside sector on the onset of the expansion phase in a substorm event, the substorm event happened at 0430UT to 0630UT on 8th Nov. 2004. The main results as follows: At the first, the data of the estimated power input (EPI) of auroral particles from NOAA/POES (Polar orbiting environmental satellite) for some 30 years have been analyzed. The variation tendencies of the EPI generally coincide with aa, AE and Dst indices. The annual variation of EPI shows equinox peaks and an asymmetric-activity with a higher peak in the winter-hemisphere than in the summer-hemisphere. The diurnal UT variations are different from north and south hemisphere: for north hemisphere, the peak appears at 1200UT, and the relative deviation is 22% to the daily average of the north hemisphere. For south hemisphere, the maximal deviation is 22% at 2000UT. So the diurnal variation of EPI is more dominant than the annual variation which maximal deviation is 3% to 12% for different seasons. Studies on correlations of the hourly average of EPI, Pa, with AE and Dst indices show a correlation coefficient r=0.74 of Pa and AE, and r=-0.55 of Pa and Dst. The hourly EPIs for north and south polar regions, NPa and SPa, show a north-south asymmetry with a higher correlation of SPa and AE (or Dst). Time delays of EPI with respect to magnetic indices are examined, the maximum correlation coefficient of Pa with AE (r=0.78) occurs when the time delay =0, suggesting a synchronous activity of auroral electrojet and auroral precipitating particles, while =1-2h, the correlation coefficient of Pa with Dst is maximum (r=0.57), suggesting that the activity of auroral particle precipitating may influence the ring current on some extent. Sencondly, we use the high-resolution magnetic field vector data of the CHAMP satellite to investigate the distribution of large-scale FACs during the great magnetic storm on 7th to 8th Nov. 2004. The results show that, whether in the northern or southern hemisphere, the number and density of large-scale FACs during the main-phase are more and bigger than these during the recover-phase, and the number of large-scale FACs in morning sector obviously is more than that in afternoon sector. In terms of the magnetic indices, we find that large-scale FACs in morning sector significantly affected by the substorm activities, while in afternoon sector the large-scale FACs mainly indicate the fluctuations of the ring-current in storm time. Accordingly to the former studies, similarly, we find that in the morning sector, the scale of the large-scale FACs move to the high-latitude region, and in the afternoon sector, large-scale FACs distinctly expand to the low-latitude region. During the time periods that the NOAA/POES auroral precipitating particle power data temporally correspond to the large-scale FACs, the more the power of auroral particle is, the more and bigger the number and density of FACs are. At the same time, we use the magnetic field vector data of POLAR obtain a good form of region 1, region 2, and three pieces of cusp FACs during a single transit at 1930UT-2006UT on 07th. And the characteristics of simultaneous electric field and energy particles observations on Polar are coincide with the five FACs pieces. Finally, by means of the observation of Cluster 4 and Goes 10、 Goes 12, we analyze the evolution process of the change of the magnetic field configuration at night sector at the expansion phase of a substorm event which happened during 0430UT to 0630UT on 8th Nov. 2004, we find that the times of the beginning of the polarizations of magnetic field are observed from Goes 10 to Goes 12 then to Cluster 4. So, at the synchronous orbit ( 6.6 RE) to 10RE distance scale of the neutral sheet, the current disruption spread tailward. Simultaneously, the strengthen of the FACs deduced from these satellites magnetic field observations are almost consistent with the times of polarizations, as well as the high energy particles injection and the electric field dominant variation. The onset times determined by the magnetic field polarizations from these satellites are all ahead of the onset time that confirmed from the auroral electrojet indices. So, these characters of different observations can be used as the criterions to determine the onset time for the substorms of such type as we studied.

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Mudstone reservoir is a subtle reservoir with extremely inhomogeneous, whose formation is greatly related to the existence of fracture. For this kind of reservoir, mudstone is oil source rock, cover rock and reservoir strata, reservoir type is various, attitude of oil layer changes greatly, and the distribution of oil and gas is different from igneous or clastic rock reservoir as well as from carbonate reservoir of self-producing and self-containing of oil and gas. No mature experience has been obtained in the description, exploration and development of the reservoir by far. Taking Zhanhua depression as an example, we studied in this thesis the tectonic evolution, deposit characteristics, diagenesis, hydrocarbon formation, abnormal formation pressure, forming of fissure in mudstone reservoir, etc. on the basis of core analysis, physical simulation, numerical simulation, integrated study of well logging and geophysical data, and systematically analyzed the developing and distributing of mudstone fissure reservoir and set up a geological model for the formation of mudstone fissure reservoir, and predicted possible fractural zone in studied area. Mudstone reservoir mainly distributed on the thrown side of sedimentary fault along the sloping area of the petroleum generatiion depression in Zhanhua depression. Growing fault controlled subsidence and sedimentation. Both the rate of subsidence and thickness of mudstone are great on the thrown side of growing fault, which result in the formation of surpressure in the area. The unlocking of fault which leads to the pressure discharges and the upward conduct of below stratum, also makes for the surpressure in mudstone. In Zhanhua depression, mudstone reservior mainly developed in sub-compacted stratum in the third segment of Shahejie formation, which is the best oil source rock because of its wide spread in distribution, great in thickness, and rich in organic matter, and rock types of which are oil source mudstone and shale of deep water or semi-deep water sediment in lacustrine facies. It revealed from core analysis that the stratum is rich in limestone, and consists of lamina of dark mudstone and that of light grey limestone alternately, such rock assemblage is in favor of high pressure and fracture in the process of hydrocarbon generation. Fracture of mudstone in the third segment of Shahejie formation was divided into structure fracture, hydrocarbon generation fracture and compound fracture and six secondary types of fracture for the fist time according to the cause of their formation in the thesis. Structural fracture is formed by tectonic movement such as fold or fault, which develops mainly near the faults, especially in the protrude area and the edge of faults, such fracture has obvious directivity, and tend to have more width and extension in length and obvious direction, and was developed periodically, discontinuously in time and successively as the result of multi-tectonic movement in studied area. Hydrocarbon generation fracture was formed in the process of hydrocarbon generation, the fracture is numerous in number and extensively in distribution, but the scale of it is always small and belongs to microfracture. The compound fracture is the result of both tectonic movement and hydrocarbon forming process. The combination of above fractures in time and space forms the three dimension reservoir space network of mudstone, which satellites with abnormal pressure zone in plane distribution and relates to sedimentary faces, rock combination, organic content, structural evolution, and high pressure, etc.. In Zhanhua depression, the mudstone of third segment in shahejie formation corresponds with a set of seismic reflection with better continuous. When mudstone containing oil and gas of abnormal high pressure, the seismic waveform would change as a result of absorb of oil and gas to the high-frequency composition of seismic reflection, and decrease of seismic reflection frequency resulted from the breakage of mudstone structure. The author solved the problem of mudstone reservoir predicting to some degree through the use of coherent data analysis in Zhanhua depression. Numerical modeling of basin has been used to simulate the ancient liquid pressure field in Zhanhua depression, to quantitative analysis the main controlling factor (such as uncompaction, tectonic movement, hydrocarbon generation) to surpressure in mudstone. Combined with factual geologic information and references, we analyzed the characteristic of basin evolution and factors influence the pressure field, and employed numerical modeling of liquid pressure evolution in 1-D and 2-D section, modeled and analyzed the forming and evolution of pressure in plane for main position in different periods, and made a conclusion that the main factors for surpressure in studied area are tectonic movement, uncompaction and hydrocarbon generation process. In Zhanhua depression, the valid fracture zone in mudstone was mainly formed in the last stage of Dongying movement, the mudstone in the third segment of Shahejie formation turn into fastigium for oil generation and migration in Guantao stage, and oil and gas were preserved since the end of the stage. Tectonic movement was weak after oil and gas to be preserved, and such made for the preserve of oil and gas. The forming of fractured mudstone reservoir can be divided into four different stages, i.e. deposition of muddy oil source rock, draining off water by compacting to producing hydrocarbon, forming of valid fracture and collecting of oil, forming of fracture reservoir. Combined with other regional geologic information, we predicted four prior mudstone fracture reservoirs, which measured 18km2 in area and 1200 X 104t in geological reserves.

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O uso dos métodos tradicionais de levantamento do uso das terras, em razão do custo elevado dos instrumentos e a dificuldade de disponibilizar as informações de maneira rápida aos tomadores de decisão, torna proibitivo seu emprego de forma sistemática e repetitiva sobre grandes extensões de território. Desta forma, existe a necessidade de se utilizar métodos que possibilitem o levantamento do uso das terras de maneira eficiente, rápida e que tenham relativamente baixo custo. Neste contexto, a forma mais eficiente e rápida para caracterizar o uso atual das terras é por meio dos recursos instrumentais oferecidos pelo sensoriamento remoto (SR), com auxílio dos Sistemas de Informações Geográficas (SIGs) e dos Sistema de Posicionamento Global (GPSs). O processo de levantamento e caracterização do uso das terras, nesse caso, pode ser grandemente facilitado pela utilização de imagens de satélites e outros recursos de sensoriamento remoto, que podem gerar dados passíveis de serem geocodificados, ou seja, integrados, relacionados e espacializados nos SIGs. Esses, em conjunto com os GPSs, são considerados, atualmente, como a maneira mais eficiente de levantamento e identificação do uso das terras. Desta forma, o trabalho teve como objetivo o mapeamento de uso das terras utilizando o processamento digital de imagem de sensoriamento remoto, utilizando-se a interpretação visual, a classificação digital supervisionada, e a classificação híbrida (classificação digital + interpretação visual), utilizando-se imagem TM do satélite LANDSAT 7.

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Informa o trabalho realizado na Bacia do Rio Camanducaia (SP/MG), para a implantação de uma unidade de conservação. Foi constituída uma base cartográfica digital sobre a área, na escala 1:250.000. Neste trabalho são apresentados e comentados 9 planos de informação cartográfica: limites, altimetria, Modelo Numérico de Terreno (MNT), MNT em 3 dimensões, hipsometria, hidrografia, bacias hidrográficas, rede viária e centros urbanos e, Imagem Landsat-TM5 da APA da Bacia do Rio Camanducaia.

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O trabalho caracterizou o meio físico do Município de Jaguariúna-SP, a partir de imagens de satélite Landsat-TM, empregando-se técnicas de geoprocessamento, com a finalidade de se estabelecer um planejamento agroambiental visando o uso e manejo sustentável de seus recursos naturais.

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O conhecimento do uso atual e cobertura do solo é imprescindível em qualquer projeto de caracterização e monitoramento ambientais, permitindo demarcar os diferentes usos da terra e vegetação, bem como subsidiar o planejamento e gestão ambientais. O presente trabalho abrange a totalidade do Estado do Rio de Janeiro, compreendido entre os meridianos 410 e 450 de longitude Oeste e os paralelos 200 30? e 230 30? de latitude Sul, estendendo-se por aproximadamente 44.000 km2. Tem como objetivo inventariar e mapear o estado atual da ocupação dos solos, distinguindo e quantificando os principais tipos de uso do solo e de cobertura vegetal, apresentados numa escala generalizada de 1:250.000. Para tal, fez-se um mapeamento preliminar com base nos padrões espectrais das imagens de satélite Landsat ETM7+, cedidas pela EMATER-RJ, utilizando-se de diferentes algoritmos de classificação espectral. Durante a elaboração da versão final do Mapa de Uso Atual e Cobertura Vegetal dos Solos do Estado do Rio de Janeiro, foram viagens de verificação in situ a fim de esclarecer dúvidas e subsidiar ajustes e modificações posteriores. O trabalho de pré-processamento, interpretação e classificação das imagens para a produção e edição final do Mapa de Uso Atual e Cobertura Vegetal realizou-se no período de março de 2002 a fevereiro de 2003, pelas equipes técnicas da CPRM (Serviço Geológico Brasileiro), Divisão de Geoprocessamento - DIGEOP, Departamento de Informações Institucionais (DEINF) e o Laboratório de Geoinformação da Embrapa Solos. Foram identificadas e mapeadas 13 grandes classes de uso e ocupação do solo, algumas delas subdivididas em tipos, assim classificadas e distribuídas: 1 ? Mata Atlântica (Remanescente/Secundária e Ciliar); 2 ? Mangue (Mangue e Mangue Degradado); 3 ? Restinga; 4 - Pecuária (Pastagem Plantada e Campo / Passtagem em Zona Úmida); 5 ? Agricultura; 6 ? Reflorestamento; 7 ? Afloramento de Rocha; 8 ? Solo Exposto; 9 ? Corpo d?Água; 10 ? Salina; 11 ? Extração de Areia / Mineração; 12 ? Praia e Duna; 13 ? Área Urbana.