Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models

Abstract Active calderas are seldom associated with circumferential eruptive fissures, but eroded magmatic complexes reveal widespread circumferential dikes. This suggests that, while the conditions to emplace circumferential dikes are easily met, mechanisms must prevent them from reaching the surfa...

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Main Authors: Fabio Corbi, Eleonora Rivalta, Virginie Pinel, Francesco Maccaferri, Valerio Acocella
Format: Article
Language:English
Published: Wiley 2016-06-01
Series:Geophysical Research Letters
Subjects:
Online Access:https://doi.org/10.1002/2016GL068721
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author Fabio Corbi
Eleonora Rivalta
Virginie Pinel
Francesco Maccaferri
Valerio Acocella
author_facet Fabio Corbi
Eleonora Rivalta
Virginie Pinel
Francesco Maccaferri
Valerio Acocella
author_sort Fabio Corbi
collection DOAJ
description Abstract Active calderas are seldom associated with circumferential eruptive fissures, but eroded magmatic complexes reveal widespread circumferential dikes. This suggests that, while the conditions to emplace circumferential dikes are easily met, mechanisms must prevent them from reaching the surface. We explain this discrepancy with experiments of air injection into gelatin shaped as a volcano with caldera. Analog dikes show variable deflection, depending on the competition between overpressure, Pe, and topographic unloading, Pl; when Pl/Pe = 4.8–5.3, the dikes propagate orthogonal to the least compressive stress. Due to the unloading, they become circumferential and stall below the caldera rim; buoyancy is fundamental for the further rise and circumferential fissure development. Numerical models quantitatively constrain the stress orientation within the gelatin, explaining the observed circumferential dikes. Our results explain how dikes propagate below the rim of felsic and mafic calderas, but only in the latter they are prone to feed circumferential fissures.
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series Geophysical Research Letters
spelling doaj-art-7c385dd2080e4e4183832b59e793f88f2025-08-20T01:50:59ZengWileyGeophysical Research Letters0094-82761944-80072016-06-0143126212621910.1002/2016GL068721Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog modelsFabio Corbi0Eleonora Rivalta1Virginie Pinel2Francesco Maccaferri3Valerio Acocella4GFZ German Centre for Geosciences, Section 2.1 Telegrafenberg GermanyGFZ German Centre for Geosciences, Section 2.1 Telegrafenberg GermanyISTerre, Université Savoie Mont‐Blanc, IRD, CNRS, Campus Scientifique Le Bourget du Lac FranceGFZ German Centre for Geosciences, Section 2.1 Telegrafenberg GermanyDipartimento di Scienze Università Roma Tre Rome ItalyAbstract Active calderas are seldom associated with circumferential eruptive fissures, but eroded magmatic complexes reveal widespread circumferential dikes. This suggests that, while the conditions to emplace circumferential dikes are easily met, mechanisms must prevent them from reaching the surface. We explain this discrepancy with experiments of air injection into gelatin shaped as a volcano with caldera. Analog dikes show variable deflection, depending on the competition between overpressure, Pe, and topographic unloading, Pl; when Pl/Pe = 4.8–5.3, the dikes propagate orthogonal to the least compressive stress. Due to the unloading, they become circumferential and stall below the caldera rim; buoyancy is fundamental for the further rise and circumferential fissure development. Numerical models quantitatively constrain the stress orientation within the gelatin, explaining the observed circumferential dikes. Our results explain how dikes propagate below the rim of felsic and mafic calderas, but only in the latter they are prone to feed circumferential fissures.https://doi.org/10.1002/2016GL068721dike propagationcalderatopographic unloadingeruptive fissure patternanalog modelsfinite element models
spellingShingle Fabio Corbi
Eleonora Rivalta
Virginie Pinel
Francesco Maccaferri
Valerio Acocella
Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
Geophysical Research Letters
dike propagation
caldera
topographic unloading
eruptive fissure pattern
analog models
finite element models
title Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
title_full Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
title_fullStr Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
title_full_unstemmed Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
title_short Understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
title_sort understanding the link between circumferential dikes and eruptive fissures around calderas based on numerical and analog models
topic dike propagation
caldera
topographic unloading
eruptive fissure pattern
analog models
finite element models
url https://doi.org/10.1002/2016GL068721
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AT virginiepinel understandingthelinkbetweencircumferentialdikesanderuptivefissuresaroundcalderasbasedonnumericalandanalogmodels
AT francescomaccaferri understandingthelinkbetweencircumferentialdikesanderuptivefissuresaroundcalderasbasedonnumericalandanalogmodels
AT valerioacocella understandingthelinkbetweencircumferentialdikesanderuptivefissuresaroundcalderasbasedonnumericalandanalogmodels