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Lucio Lirer Rosalba Munno Immacolata Postiglione Anna Vinci Livia Vitelli 《Bulletin of Volcanology》1997,59(2):112-124
Due to the lack of an effective policy of planning and prevention, over the past decades the area around Mt. Vesuvio has
undergone a steady increase in population and uncontrolled housing development. Consequently, it has become one of the most
hazardous volcanic areas in the world. In order to mitigate the damage that the impact of an explosive event would cause in
the area, the Department of Civil Defense has worked out an Emergency Management Plan using the A.D. 1631 subplinian eruption
as the most probable short-term event. However, from 25 000 years B.P. to present, the activity of the Somma-Vesuvio volcano
has shown a sequence of eight eruptive cycles, which always began with a strong plinian eruption. In this paper we utilize
the A.D. 79 eruption as an example of a potential large explosive eruption that might occur again at Vesuvio. A detailed tephrostratigraphic
analysis of the eruption products was processed by a multivariate statistical analysis. This analysis proved useful for identifying
marker layers in the sequences, thus allowing the recognition of some major phases of synchronous deposition and hence the
definition of the chronological and spatial evolution of the eruption. By combining this reconstruction with land-use maps,
a scenario is proposed with time intervals in the eruptive sequence similar to those reported in Pliny's letter. Thus, it
was calculated that, after 7 h from the start of the eruption, a total area of approximately 300 km2 would be covered with the eruption products. In the following 11 h, a total area of approximately 500 km2 would be involved. The third and last phase of deposition would not cause significant variation in the total area involved,
but it would bring about an increase in the thickness of the pyroclastic deposits in the perivolcanic area.
Received: 30 November 1996 / Accepted: 29 May 1997 相似文献
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Hierarchical spatial interaction among the Italian regions: a nonlinear relative dynamics approach 总被引：2，自引：2，他引：0
Regional interactions and spillover effects should be considered as important factors in growth analysis of regional economies.
Using modified versions of the Dendrinos–Sonis model, this paper analyses the spatial hierarchical system of Italy. The interaction
among Italian regions is considered at three different levels of spatial aggregation, the NUTS-1, NUTS-2 and NUTS-3 levels.
Compared to more popular spatial econometric approaches, the Dendrinos–Sonis model and its extensions provide greater flexibility
in the way interaction between regions is handled but the results strongly depend on the choice of a reference region.
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| Geoffrey J. D. HewingsEmail: |
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