Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/9643
Authors: Cioni, R.* 
Longo, A.* 
Macedonio, G.* 
Santacroce, R.* 
Sbrana, A.* 
Sulplizio, R.* 
Andronico, D.* 
Title: Assessing pyroclastic fall hazard through field data and numerical simulation: Example from Vesuvius
Journal: Journal of Geophysical Research 
Series/Report no.: /108 (2003)
Issue Date: 2003
DOI: 10.1029/2001JB000642
Keywords: pyroclastic flows, numerical simulations
Subject Classification04. Solid Earth::04.08. Volcanology::04.08.03. Magmas 
Abstract: A general methodology of pyroclastic fall hazard assessment is proposed on the basis of integrated results of field studies and numerical simulations. These approaches result in two different methods of assessing hazard: (1) the ‘‘field frequency,’’ based on the thickness and distribution of past deposits and (2) the ‘‘simulated probability,’’ based on the numerical modeling of tephra transport and fallout. The proposed methodology mostly applies to volcanoes that, by showing a clear correlation between the repose time and the magnitude of the following eruptions, allows the definition of a reference ‘‘maximum expected event’’ (MEE). The application to Vesuvius is shown in detail. Using the field frequency method, stratigraphic data of 24 explosive events in the 3–6 volcanic explosivity index range in the last 18,000 years of activity are extrapolated to a regular grid in order to obtain the frequency of exceedance in the past of a certain threshold value of mass loading (100, 200, 300, and 400 kg/m2). Using the simulated probability method, the mass loading related to the MEE is calculated based on the expected erupted mass (5 1011 kg), the wind velocity profiles recorded during 14 years, and various column heights and grain-size populations. The role of these factors was parametrically studied performing 160,000 simulations, and the probability that mass loading exceeded the chosen threshold at each node was evaluated. As a general rule, the field frequency method results are more reliable in proximal regions, provided that an accurate database of field measurements is available. On the other hand, the simulated probability method better describes events in middle distal areas, provided that the MEE magnitude can be reliably assumed. In the Vesuvius case, the integration of the two methods results in a new fallout hazard map, here presented for a mass loading value of 200 kg/m2.
Appears in Collections:Article published / in press

Files in This Item:
File Description SizeFormat
2003_JGR_Cioni_et_al.pdf2003_JGR_Cioni_et_al952.14 kBAdobe PDFView/Open
Show full item record

WEB OF SCIENCETM
Citations

85
checked on Feb 10, 2021

Page view(s) 50

190
checked on Feb 4, 2023

Download(s) 50

271
checked on Feb 4, 2023

Google ScholarTM

Check

Altmetric