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1.

The last few years have seen the debate on the geoethics of environmental and climatic protection growing to include resilience as a central idea within this new discipline, which holds many similarities with geography. Resilience analysis often looks at the capacity to re-establish conditions of equilibrium within a system which has been hit by a serious shock, e.g. a natural or man-made disaster. Geoethics works, in tandem with geological analyses and the geography of risk, to inform a population and develop integrated risk management in such a way as to strengthen a community’s resilience. The aim of this work is to study some people’s capacity to overcome what was potentially a disastrous event and, through a process of reconstruction, turn it into an occasion for growth. The experiment, carried out in the primary and middle schools in Aiello Calabro (Calabria, southern Italy), was conducted on the basis of the belief that there is a close relationship between a population’s having a realistic understanding of the risk of such an event, e.g. an earthquake, and high levels of resilience. We also tried to gain an insight into the relationship that may exist between resilience in primary and secondary school children and methods of coping which give an appropriate management of seismic risk. To be more precise, we try to discover whether there is a link between good/appropriate resilience and good/appropriate risk management.

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2.
Zusammenfassung Nach dem Erdbeden von Nanka?do im Jahre 1946 hat man das Dreiecksnetz I. Ordnung in einem Gebiet von etwa 300 km Umkreis wiederbeobachtet, und zwar auf 47 Punkten insgeasamt 68 Winkel. Die letzte Triangulation fand in den Jahren 1885–96 statt.—Nach der Ausgleichung des Netzes wurden Punkverschiebungen bis zu 1,69 m festgestellt.
Resumen Después del temblor de tierra de 1946, en Nanka?do, se ha vuelto a observar la red de triangulación de 1H orden en un radio de 300 kilómetros aproximadamente. Los puntos de nuevo observados son 47 y los triángulos 68. La triangulaciín precedente se remontaba a los a?os 1885–96. Después de compensar la red, se han deducido los desplazamientos experimentados por los puntos sobre el terreno, que llegaron a ser de 1,69 metros.

Résumé Après le tremblement de tèrre de 1946 à Nankaido, on a réobservé le réseau de triangulation de premier ordre dans un rayon de 300 km environ. Les points réobservés sont au nombre de 47, et les triangles en nombre de 68. La triangtlation précédente remontait aux années 1885–96. La compensation du réseau effectuée, on en a déduit les déplacements subis par les points sur le terrain, qui importent jusqu’à 1,69 m.

Sommario Dopo il terremoto di Nankaido del 1946, è stata riosservata la rete di prim’ordine entro un raggio di circa 300 km. La precedente triangolazione risaliva agli anni 1885–96. Effettuata la compensazione, il confronto fra l’anticae la nuova triangolazione ha rivelato spostamenti nei vertici ammontanti fino a m 1,69.


Communication présentée à l’Assemblée Générale de Bruxelles en 1951  相似文献   
3.
Devolatilization reactions during prograde metamorphism are a key control on the fluid distribution within subduction zones. Garnets in Mn-rich quartz schist within the Sanbagawa metamorphic belt of Japan are characterized by skeletal structures containing abundant quartz inclusions. Each quartz inclusion was angular-shaped, and showed random crystallographic orientations, suggesting that these quartz inclusions were trapped via grain boundary cracking during garnet growth. Such skeletal garnet within the quartz schist formed related to decarbonation reactions with a positive total volume change (?V t > 0), whereas the euhedral garnet within the pelitic schists formed as a result of dehydration reaction with negative ?V t values. Coupled hydrological–chemical–mechanical processes during metamorphic devolatilization reactions were investigated by a distinct element method (DEM) numerical simulation on a foliated rock that contained reactive minerals and non-reactive matrix minerals. Negative ?V t reactions cause a decrease in fluid pressure and do not produce fractures within the matrix. In contrast, a fluid pressure increase by positive ?V t reactions results in hydrofracturing of the matrix. This fracturing preferentially occurs along grain boundaries and causes episodic fluid pulses associated with the development of the fracture network. The precipitation of garnet within grain boundary fractures could explain the formation of the skeletal garnet. Our DEM model also suggests a strong influence of reaction-induced fracturing on anisotropic fluid flow, meaning that dominant fluid flow directions could easily change in response to changes in stress configuration and the magnitude of differential stress during prograde metamorphism within a subduction zone.  相似文献   
4.
The application of geometric modeling to shelf‐margin stratigraphy has the potential to constrain interpretations of external forcings on margin development. Here we apply such a model to the Ebro margin in order to complement the analysis of Kertznus & Kneller (2009) . Our results suggest that increased mass wasting in the Pleistocene was unlikely to have been a factor in the observed long‐term shelf‐edge trajectory, and that the trajectory can be explained by the interaction of sediment flux, relative sea‐level rise, and basin shape.  相似文献   
5.
The profile of a river that conveys sediment without net deposition and net erosion is referred to as ‘graded’ with respect to vertical aggradation of the river segment. Three experimental series, designed in terms of the autostratigraphic view of alluvial grade, were conducted to clarify the diagnostic spatial behaviour of graded alluvial–deltaic rivers: an ‘R series’, which utilized a moving boundary setting with a stationary base level; an ‘F series’ in a fixed boundary setting with a stationary base level to produce ‘forced grade’; and an ‘M series’ in a moving boundary setting with constant base‐level fall to produce ‘autogenic grade.’ The results of the three experimental series, combined with geometrical modelling of the effects of basin water depth and other experimental data, suggest the following: (i) in a graded alluvial–deltaic system, lateral shifting and avulsing of active distributary channels are suppressed regardless of whether the downstream boundary of the deltaic system is fixed; (ii) in a delta with a downstream‐fixed boundary, the graded streams are stabilized within a valley that is incised in the axial part of the delta plain, whereby the alluvial plain outside the valley is abandoned and terraced; (iii) in moving boundary settings, the graded river simply extends basinward as a linearly elongated channel and lobe system without cutting a valley; and (iv) a modern forced‐graded alluvial river is most likely to be found in a valley incised into a fan delta in front of very deep water, and the stratigraphic signal of fossil autogenic‐graded rivers will be found in deltaic successions that accumulated in the outer to marginal areas of deltaic continental shelves during sea‐level falls. This renewed autostratigraphic view of alluvial grade suggests a thorough reconsideration of the conventional understanding that an alluvial river feeding a progradational delta is graded with a stationary base level.  相似文献   
6.
The theory of physical interaction field by a differential geometrical approach combines the deformation field with the physical field (e.g., electromagnetic field), and derives a new tensorial relation between the deformation and the dielectric anisotropy of the crustal rocks. This relation can be applied to dielectric anisotropies of deformed natural rocks such as mylonites or gneisses. The dielectric anisotropies of mylonites are observed to increase as plastic strains of mylonites increase. Moreover, the derived tensorial relation can be linked to the electromagnetic potential field (deformational anomalies) in a deformed crust. A physico-geometrical consideration on this theory of physical interaction field is mathematically similar to ones on the theory of field in the Finsler space or on the concept of a unified gauge field.  相似文献   
7.
In this paper we present the results of an integrated geomorphological, pedological and stratigraphical study carried out along the Ionian coast of northern Calabria (southern Italy). This area is characterised by the occurrence of five orders of alluvial terraces that are striking features of the landscape, where large and steep catchments debouch from the mountain front to the hilly coastal belt.Field investigations indicate that the deposits of all five terraces are suggestive of shallow gravel-bed braided streams.On the basis of the age of the Pleistocene substratum and morphostratigraphic correlation with marine terraces cropping out in the nearby areas, each order has been associated to specific marine oxygen isotope stages.Consequently, we focused on the interplay of allocyclic factors influencing stream aggradation/degradation. Soil features and other climatic proxies suggest that climate didn't play an important role with respect to tectonic and base-level changes in controlling fluvial dynamics.In particular, we recognised that during the middle Pleistocene the study area experienced a period of subaerial landscape modelling, as suggested by the thick and complex alluvial sequence of the highest terrace (T1). The onset of regional uplift marks a change in the geomorphic scenario, with tectonic and eustatically driven changes in base-level working together in causing switches in fluvial aggradational/erosional phases (T2–T5 terraces). Because of the uplift, river dissection occurred during phases of sea level fall, whereas aggradation phases occurred during periods of climate amelioration (sea level rise) just before highstands were attained.As a consequence, the stepped terraces in the study area reflect the interplay between tectonics (uplift) and sea level changes, in which terraces define episodes of relative sea level fall during the late Quaternary.  相似文献   
8.
Sandstone tidal cross‐strata are the predominant sedimentary feature of strait‐fill stratigraphic successions. However, although widely described in numerous studies, tidal strait‐fill two‐dimensional and three‐dimensional cross‐strata have rarely been reported to occur in discrete intervals which are laterally adjacent or vertically stacked, and the meaning of this stratigraphic architecture has not yet been fully investigated. Understanding of the processes responsible for changes in the internal features of modern and ancient tidal bedforms is essential in order to predict lateral and vertical heterogeneities in analogous reservoir strata. This facies‐based study aims to interpret the three‐dimensional to two‐dimensional cross‐strata transition observed in the lower Pleistocene mixed siliciclastic/bioclastic sandstone filling the Catanzaro Strait, in southern Italy, during a continuous phase of tectonically driven marine transgression. Tidal cross‐strata disappear in the uppermost interval of the studied succession, where mudstone strata prevail. This stratigraphic trend is interpreted as the evidence of an important change in the tidal strait hydrodynamics due to a phase of relative sea‐level rise. At the beginning of the transgression, three‐dimensional tidal dunes migrated throughout the ca 3 to 4 km wide and ca 30 km long, WNW–ESE‐oriented Catanzaro Strait, due to strong tidal currents amplified through the seaway and flowing in semi‐diurnal phase opposition. As the intermediate phase of transgression enlarged the seaway width, the tidal current strength decreased as tidal water exchange occurred over a larger cross‐sectional area. The progressive reduction of the bed shear stress modified three‐dimensional tidal dunes into an extensive two‐dimensional bedform field. At the end of the transgression, the further widening of the Catanzaro Strait into a ca 10 to 12 km wide marine passageway changed the tidally dominated strait into a non‐tidal open shelf. The results of this research suggest the presence of a ‘critical cross‐sectional area’ in the narrowest strait‐centre zone which controls the activation and deactivation of tidal current amplification along a marine seaway.  相似文献   
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