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51.
Archive aerial photos have been used to create a skeletal history for several toxic waste sites currently under investigation in the United States. Because many of the sites are very small in area, and the majority of the historical aerial photography is not large scale, specialized methods have, through experience, been developed to do this work. The result of the work is a series of standard format film stereograms and a detailed report. The report includes several unique methods for presenting the airphoto findings.  相似文献   
52.
中国南方海相含油气保存单元的层次划分与综合评价   总被引:1,自引:0,他引:1  
以最近十年中国南方的海相新区油气勘探评价成果为依托 ,以油气成藏和整体封闭保存体系评价为核心 ,在渝东—湘鄂西、中下扬子和滇黔桂三大区域划分出 9个有利区块 5 1个含油气保存单元 ,并将其归纳为四个层次。综合评价认为 ,方西和石柱保存单元具有较好的整体封存体系 ,属持续性含油气保存单元 ,为首选勘探目标 ;江汉盆地南部、句容—海安区块、南鄱阳坳陷、楚雄盆地东北部具备或基本具备整体封存条件 ,属于沉积重建型含油气保存单元 ,通过精细勘探可望获得商业性油气流 ;楚雄盆地西北部、南盘江坳陷、十万大山盆地和渝东—湘鄂西地区利川复向斜由于晚期强烈构造改造而仅存在部分封存体系 ,需要攻关探索 ;思茅、渝东—湘鄂西地区的花果坪和桑植—石门地区已失去整体封闭保存条件 ,仅局部存在封存体系 ,地质条件高度复杂 ,勘探风险甚高。  相似文献   
53.
Zusammenfassung Die alpine Krustenverkürzung (300–400 km oder mehr im Profil der Westschweiz, 400–500 km oder mehr im Profil der Ostschweiz) erfolgte in diskreten orogenen Phasen, welche durch Zeiten langsamerer Bewegung oder eigentlicher Remission getrennt waren. Während der wichtigsten Phase, an der Eozän-Oligozän-Wende, betrug die Relativgeschwindigkeit der nördlichen Platte und der südlichen Kleinplatte einige cm/a.
Crustal shortening in the Central Alps (300–400 km or more in western Switzerland, 400–500 km or more in eastern Switzerland) occurrend in discrete orogenic phases, separated by times of slower movement or of complete stop. During the most important phase, at the turn from the Eocene to the Oligocene, the rate of relative movement of the northern plate and the southern microplate was of the order of several cm/y.

Résumé Le raccourissement de la croûte dans les Alpes Centrales (300–400 km ou davantage en Suisse occidentale, 400–500 km ou davantage en Suisse orientale) se fit par phases orogéniques défines, séparées par des intervalles à mouvement plus lent ou même à arrêt total. Pendant la phase principale, à la fin de l'Eocène ou au début de l'Oligocène, la vitesse relative de la plaque septentrionale et de la microplaque méridionale était de l'ordre de plusieurs cm/a.

(300–400 , , 400–500 , ) , , . , - , /.
  相似文献   
54.
In this paper, the responses of the interaction system of R.C. gravity single-leg platform to seismic excitation are mainly analysed. A set of nonlinear equations for the interaction system are established by using the wave, one is the soil-structure interaction and the other is the fluid-structure interaction. The seismic response of the interaction system is analysed for the influence of the asymmetric structure, fluid action, etc. with the input of seismic SH waves in any direction. The numerical results are given for a simple example.  相似文献   
55.
56.
An analysis of the historical and cultural context of a large number of literary works illuminates the concept of landscape, a recurrent theme in contemporary humanistic geography. In this context, the works of Ippolito Nievo present an opportunity to look closer at the socio-economic circumstances of his time while also offering suggestive interpretative elements about the attitudes held concerning the wetlands of the lower Friulan plain.  相似文献   
57.
58.
Ruppert H 《GeoJournal》1991,25(1):7-12
The ethnic identities of the various population groups in the Sudan are a product of their specific natural and social environments. The migration of these groups to the towns, especially to Greater Khartoum, involves a drastic change of cultural norms and values. However, the capability of change and the subsequent results are strongly conditioned by the specific background of each ethnic group and by the conditions in its area of origin. This is being proved by a comparative study on three ethnic groups in the Sudan: the Nuba, the Zaghawa and the Hadandawa.  相似文献   
59.
60.
A biogeochemical characterization of the Madeira river basin has been made to evaluate the local and global effects of possible alterations in the ecosystem caused by recent intensive occupation in Rondonia state. During the period April 1983—January 1986, sampling was made both by land and river along the tributaries and main channel of the Madeira river. The parameters analysed lead to a detailed study of the physicochemical quality of the waters of the basin and their relationship with the local geology, associated with the transport of solid material and the hydrological behavior of the ecosystem.Penman's method adapted to tropical rainforest conditions was used to evaluate the potential evapotranspiration for the basin. Estimated potential evapotranspiration was 1420 mm/y, 77% due to the energy balance. Real evapotranspiration was 94% of the estimated potential and the main residence time of the rain water in the basin was 2 months. The isotopic behavior of Hydrogen and Oxygen in the river waters of the region was typical of great rivers, the values being more positive during the dry season and more negative during the rainy season. An isotopic gradient of 18O 0.038 ()/100 km, was established from Porto Velho station to the estuary, which was considered low when compared with the value of 0.063 ()/100 km, obtained for the Amazon river.In general, the waters of the tributaries were poor in dissolved ion species when compared with the main channel of the Madeira river. Seasonal variation in the transport of suspended sediment kept the same pattern, greater transport being observed on rising water than during high water. A transport of 2.85 million tons per day was observed in the Madeira river near the mouth.  相似文献   
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