Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach
<p>In this paper we present a new model for the simulation of lahars based on the depth-averaged code IMEX-SfloW2D with new governing and constitutive equations introduced to better describe the dynamics of lahars. A thorough sensitivity analysis is carried out to identify the critical process...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2024-04-01
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| Series: | Solid Earth |
| Online Access: | https://se.copernicus.org/articles/15/437/2024/se-15-437-2024.pdf |
| _version_ | 1797225502090461184 |
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| author | M. de' Michieli Vitturi A. Costa M. A. Di Vito L. Sandri D. M. Doronzo |
| author_facet | M. de' Michieli Vitturi A. Costa M. A. Di Vito L. Sandri D. M. Doronzo |
| author_sort | M. de' Michieli Vitturi |
| collection | DOAJ |
| description | <p>In this paper we present a new model for the simulation of lahars based on the depth-averaged code IMEX-SfloW2D with new governing and constitutive equations introduced to better describe the dynamics of lahars. A thorough sensitivity analysis is carried out to identify the critical processes (such as erosion and deposition) and parameters (both numerical and physical) controlling lahar runout using both synthetic and real case topographies. In particular, an application of the model to a syn-eruptive lahar from a reference size eruption from Somma–Vesuvius, affecting the Campanian Plain (southern Italy), described in Di Vito et al. (2024), is used in this work for the sensitivity analysis. Effects of erosion and deposition are investigated by comparing simulations with and without these processes. By comparing flow thickness and area covered by the flow and their evolution with time, we show that the modelling of both the processes is important to properly simulate the effects of the bulking and debulking as well as the associated changes in rheology. From a computational point of view, the comparisons of simulations obtained for different numerical grids (from 25 to 100 m), scheme order, and grain size discretization were useful to find a good compromise between resolution and computational speed. The companion paper by Sandri et al. (2024) shows an application of the presented model for probabilistic volcanic hazard assessment for lahars from Vesuvius deposits in the Neapolitan area.</p> |
| first_indexed | 2024-04-24T14:10:02Z |
| format | Article |
| id | doaj.art-b9d4cb1f1eaf462baf65a02a52f1fff0 |
| institution | Directory Open Access Journal |
| issn | 1869-9510 1869-9529 |
| language | English |
| last_indexed | 2024-04-24T14:10:02Z |
| publishDate | 2024-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Solid Earth |
| spelling | doaj.art-b9d4cb1f1eaf462baf65a02a52f1fff02024-04-03T09:31:43ZengCopernicus PublicationsSolid Earth1869-95101869-95292024-04-011543745810.5194/se-15-437-2024Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approachM. de' Michieli Vitturi0A. Costa1M. A. Di Vito2L. Sandri3D. M. Doronzo4Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, Pisa, 56125, ItalyIstituto Nazionale di Geofisica e Vulcanologia, Sezione di Bologna, Bologna, 40128, ItalyIstituto Nazionale di Geofisica e Vulcanologia, Osservatorio Vesuviano, Naples, 80124, ItalyIstituto Nazionale di Geofisica e Vulcanologia, Sezione di Bologna, Bologna, 40128, ItalyIstituto Nazionale di Geofisica e Vulcanologia, Osservatorio Vesuviano, Naples, 80124, Italy<p>In this paper we present a new model for the simulation of lahars based on the depth-averaged code IMEX-SfloW2D with new governing and constitutive equations introduced to better describe the dynamics of lahars. A thorough sensitivity analysis is carried out to identify the critical processes (such as erosion and deposition) and parameters (both numerical and physical) controlling lahar runout using both synthetic and real case topographies. In particular, an application of the model to a syn-eruptive lahar from a reference size eruption from Somma–Vesuvius, affecting the Campanian Plain (southern Italy), described in Di Vito et al. (2024), is used in this work for the sensitivity analysis. Effects of erosion and deposition are investigated by comparing simulations with and without these processes. By comparing flow thickness and area covered by the flow and their evolution with time, we show that the modelling of both the processes is important to properly simulate the effects of the bulking and debulking as well as the associated changes in rheology. From a computational point of view, the comparisons of simulations obtained for different numerical grids (from 25 to 100 m), scheme order, and grain size discretization were useful to find a good compromise between resolution and computational speed. The companion paper by Sandri et al. (2024) shows an application of the presented model for probabilistic volcanic hazard assessment for lahars from Vesuvius deposits in the Neapolitan area.</p>https://se.copernicus.org/articles/15/437/2024/se-15-437-2024.pdf |
| spellingShingle | M. de' Michieli Vitturi A. Costa M. A. Di Vito L. Sandri D. M. Doronzo Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach Solid Earth |
| title | Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach |
| title_full | Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach |
| title_fullStr | Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach |
| title_full_unstemmed | Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach |
| title_short | Lahar events in the last 2000 years from Vesuvius eruptions – Part 2: Formulation and validation of a computational model based on a shallow layer approach |
| title_sort | lahar events in the last 2000 years from vesuvius eruptions part 2 formulation and validation of a computational model based on a shallow layer approach |
| url | https://se.copernicus.org/articles/15/437/2024/se-15-437-2024.pdf |
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