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141.
This article outlines three modalities of relation between literature and geography: the literary work as demonstrative element, the literary work as collective image, and the literary work as analogous process. The verification of the three modalities takes place through an approachment to the local literature using a geographical concept, namely region, and a particular area: the province of Mendoza, in western Argentina. Ten literary works of different genre were selected to which content analysis was applied. First the relevance of these representations at the initiation of geographical research is verified and then the way in which they stimulate the definition of problems and the formulation of hypotheses is addressed.  相似文献   
142.
For the testing of the effect on the tsunami prevention facilities, a simplified methodfor tsunami risk assessment was suggested without wave run-up analysis. This methodis proposed using calculated offshore tsunami waveform and field reconnaissance suchas the seawall height, time necessary for residents' evacuation and tsunami warninginsurance. Then, two normalized values are evaluated; one is the ratio of calculatedmaximum tsunami height to seawall height, the other is the ratio of time betweentsunami over-topping and evacuation completion to total time required for evacuation.These two values are used to qualitatively estimate the safety of residents and the effectof tsunami prevention facilities, eliminating the necessity to compute complicatedtsunami run-up onshore.  相似文献   
143.
As a tool to understand Tierra del Fuego’s basic ecology and detect changes due to human pressures, this study develops habitat bioindicators. We compared the freshwater benthic macroinvertebrates at 61 study sites in six habitat types: grassland streams, urbanised streams, forested streams, beaver ponds, lakes and peat bog ponds. Forty-nine taxa were identified; insects were the most diverse group. Beaver pond, lake and grassland stream assemblages were similar, as were those from lakes, grassland streams and peat bog ponds. Fourteen taxa were habitat-specific. In forests, these included mayfly scrapers (Andesiops, Meridialaris) and blackfly filterers (Gigantodax). In lakes, two copepod filterers were indicators, and in urban streams, one shredder (Aphroteniella) and three collector-gatherers (springtail, earthworm, aquatic worm). Predators (Corixa, Aeshna) were characteristic of peat bog ponds. Beaver ponds had no indicator species. Establishing links between species and ecosystems constitutes the beginning of a broader effort to understand anthropogenic impacts to Fuegian watersheds.  相似文献   
144.
Goodness of empirical models for predicting explosive detonation velocity and pressure was analysed using 3 databases consisting of experimental velocity and pressure measurements for different explosives. The first database was used to estimate experimental errors for detonation velocity and pressure measurements. The second database was used to compare residuals obtained by the experimental models and by various thermochemical codes. Finally, the third database, consisting of some 600 data on 130 explosive substances, was used to estimate residual bias and dispersion resulting from the application of the experimental models. Also analysed was model coherence with the ideal detonation theory. Our main conclusion is that all the models introduce bias in their predictions depending on the density and oxygen balance values of the explosive. Of those analysed, the Xiong model was notable for its good results, with residual dispersion comparable to that obtained from application of the best thermochemical codes. Our results would indicate that the Xiong model is the only model that may be compatible with the ideal detonation theory. The pressure equation derived from the ideal detonation theory and calibrated with experimental data had excellent predictive capacity.  相似文献   
145.
Magnetic fabric allows to unravel the petrofabrics of sedimentary rocks and to assess their deformational history. The use of this technique, in addition to classical structural field observations in the limbs of seven asymmetric folds in the Pyrenees, helps to determine the differences of internal deformation as well as the folding kinematics. Three folds developed during the Variscan Orogeny in Ordovician and Devonian rocks, and four folds developed during the Pyrenean Orogeny in Eocene rocks, are studied. Folds show a variety of structural locations, in different thrust sheets of the Southern Central Pyrenees, different cleavage development, age, geometry and lithology. Sampling follows an equivalent lithological layer in the two limbs, except for one case, of the selected folds. Results show a modified tectonic magnetic fabric in most sites with the magnetic lineation on the tectonic foliation plane. A larger scattering of the magnetic lineation (maximum magnetic anisotropy axis) and a higher intensity of the preferred orientation of minerals (eccentricity of the anisotropy of magnetic susceptibility - AMS ellipsoid) is better observed in the overturned (short) limb of the asymmetric Variscan folds than in the normal (long) limb. On the other hand, the shape parameter in Alpine folds is generally larger in the overturned (short) limb then in the normal (long) one. A good clustering of the minimum magnetic anisotropy axes is observed in all limbs. The combination of the AMS data with the structural data helps to understand and better constrain the deformation degree in these asymmetric folds and to unravel the deformational history.  相似文献   
146.
Oceanology - In February and July 2014, multidisciplinary geochemical studies of the sediments were carried out at two stations. One of them was located in Voevoda Bight, which has a bottom depth...  相似文献   
147.
Although the trajectory and geometry of clinoforms in different types of basins have been described in many studies, few studies discuss the influence of halokinesis on clinoforms in salt-related basins. In this study, we analyse the Lower Cretaceous clinoforms in the Tiddlybanken Basin, Norwegian Barents Sea to evaluate the impact of salt mobilization on the geometry and trajectory of clinoforms as well as its implications on sediment partitioning. To accomplish this objective, we use a multidisciplinary approach consisting of seismic and well-interpretation, 3D structural restoration, and forward stratigraphic modelling. The results show that salt mobilization affects prograding clinoforms by: (a) causing lateral variations in progradation rates, resulting in complex palaeogeography, (b) increasing slope angles, which affect the equilibrium of the clinoform profile and can trigger slope-readjustment processes and (c) producing lateral and temporal variations in accommodation space, leading to different clinoform trajectories, stacking patterns and reservoir distribution along the basin. Forward stratigraphic modelling shows that in salt-related basins and other tectonically active basins, the isolated use of conventional methods for clinoform analysis might lead to potential interpretation pitfalls such as misinterpretation of trajectories and overestimation of foreset angles, which can have negative consequences for exploration models.  相似文献   
148.
基于AHP_熵权法的孟印缅地区洪水灾害风险评估   总被引:2,自引:1,他引:1  
孟印缅三国地处亚热带与热带季风气候区,因自然条件制约,洪涝灾害频繁发生,对“孟中印缅经济走廊”建设将会带来重大影响。开展孟印缅地区的洪水风险评估可为“孟中印缅经济走廊”的建设安全提供必要的信息和科技支撑。利用1980—2016年的降水数据,结合河网、数字高程和土地利用等数据,选取雨季降雨量、暴雨天数、高程、坡度、河网密度、植被覆盖度、土壤可蚀性、人口密度、地均GDP和土地利用10个指标,采用层次分析法和AHP_熵权法对孟印缅地区的洪水灾害风险分布进行了比较研究。研究表明:孟印缅地区高风险区和较高风险区分别占总面积的1.05%和28.76%,高风险区主要分布在印度北部的恒河平原、印度东北部的阿萨姆邦、孟加拉国大部分地区和缅甸南部。受自然、人口和经济条件的制约,孟加拉国是孟印缅三国中洪水风险最高的国家,高风险区和较高风险区分别占总面积的10.61%和65.87%。层次分析法和AHP_熵权法结果间的比较表明,后者比前者识别出更大范围的洪水高风险区。本研究为中国开展周边国家自然灾害的风险评估提供了有效的方法,有助于推进国家孟中印缅经济走廊的建设。  相似文献   
149.
By means of physicochemical modeling with the Selector software package, a model for the mixing of riverine water (pH = 7.02) and seawater was compiled and calculated. The Razdol’naya River-Amur Bay (Sea of Japan) system was assessed as an example. By means of the MINTEQA2/PRODEFA2 software package, the role of the sorption processes in riverine and marine waters, as well as in the zone of their mixing, was ascertained. The physicochemical migration forms of microelements (arsenic, vanadium, chromium, cobalt, and mercury) in the waters of the geochemical system considered and their behavior in passing through the geochemical barrier were established.  相似文献   
150.
Within the framework of the multidisciplinary RECS project and with the aim of describing the particle flux transfer from the continental shelf to the deep basin, an array of five mooring lines equipped with a total of five pairs of PPS3/3 sequential-sampling sediment traps and RCM-7/8 current meters were deployed 30 m above the bottom from March 2003 to March 2004 inside and outside the Blanes Canyon. One mooring line was located in the upper canyon at 600 m depth, one in the canyon axis at 1700 m depth and other two close to the canyon walls at 900 m depth. A fifth mooring line was deployed in the continental open slope at 1500 m water depth.The highest near-bottom downward particle flux (14.50 g m−2 d−1) was recorded at the trap located in the upper canyon (M1), where continental inputs associated with the presence of the Tordera River are most relevant. On the other hand, the downward fluxes (4.35 g m−2 d−1) in the canyon axis (M2) were of the same order as those found in the western flank (M3) of the canyon. Both values were clearly higher than the value (1.95 g m−2 d−1) recorded at the eastern canyon wall (M4). The open slope (M5) mass flux (5.42 mg m−2 d−1) recorded by the sediment trap located outside the canyon system was three orders of magnitude lower than the other values registered by the inner canyon stations. The relevance of our data is that it explains how the transport pathway in the canyon occurs through its western flank, where a more active and persistent current toward the open ocean was recorded over the entire year of the experiment.Off-shelf sediment transport along the canyon axis showed clear differences during the period of the study, with some important events leading to strong intensifications of the current coupled with large transport of particle fluxes to the deepest parts of the canyon. Such events are primarily related to increases in river discharge and the occurrence of strong storms and cascading events during the winter.In summary, in this study it is shown that the dynamics of the water masses and the currents in the study area convert the sharp western flank of the Blanes Canyon in a more active region that favors erosion processes than the eastern flank, which has a smoother topography and where the absence of erosional conditions yields to steadier sedimentary processes.  相似文献   
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