Abstract
| Original language | English |
|---|---|
| Article number | 48 |
| Pages (from-to) | 1-19 |
| Number of pages | 19 |
| Journal | Bulletin of Volcanology |
| Volume | 80 |
| Issue number | 5 |
| Early online date | 16 Apr 2018 |
| DOIs | |
| Publication status | Published - May 2018 |
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Keywords
- Rhyolite
- Blocky lava flow
- Folds
- High viscosity
- Deformation
- Obsidian
Cite this
Emplacement of the Rocche Rosse rhyolite lava flow (Lipari, Aeolian Islands). / Bullock, Liam A (Corresponding Author); Gertisser, Ralf ; O’Driscoll, Brian.
In: Bulletin of Volcanology, Vol. 80, No. 5, 48, 05.2018, p. 1-19.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Emplacement of the Rocche Rosse rhyolite lava flow (Lipari, Aeolian Islands)
AU - Bullock, Liam A
AU - Gertisser, Ralf
AU - O’Driscoll, Brian
N1 - The authors acknowledge Airbus Defence and Space for providing satellite imagery, financial support from Keele University and fieldwork grants from the Mineralogical Society of Great Britain and Ireland and the Volcanic and Magmatic Studies Group. LAB wishes to thank Leanne Patrick and James Watling for fieldwork assistance. The authors are grateful for the thorough and constructive comments from Guido Giordano and an anonymous reviewer, as well as the careful editorial handling of Kathy Cashman and Andrew Harris, which greatly improved this manuscript. Open access via Springer Compact
PY - 2018/5
Y1 - 2018/5
N2 - The Rocche Rosse lava flow marks the most recent rhyolitic extrusion on Lipari island (Italy), and preserves evidence for a multi-stage emplacement history. Due to the viscous nature of the advancing lava (108 to 1010 Pa s), indicators of complex emplacement processes are preserved in the final flow. This study focuses on structural mapping of the flow to highlight the interplay of cooling, crust formation and underlying slope in the development of rhyolitic lavas. The flow is made up of two prominent lobes, small (< 0.2 m) to large (> 0.2 m) scale folding and a channelled geometry. Foliations dip at 2–4° over the flatter topography close to the vent, and up to 30–50° over steeper mid-flow topography. Brittle faults, tension gashes and conjugate fractures are also evident across flow. Heterogeneous deformation is evident through increasing fold asymmetry from the vent due to downflow cooling and stagnation. A steeper underlying topography mid-flow led to development of a channelled morphology, and compression at topographic breaks resulted in fold superimposition in the channel. We propose an emplacement history that involved the evolution through five stages, each associated with the following flow regimes: (1) initial extrusion, crustal development and small scale folding; (2) extensional strain, stretching lineations and channel development over steeper topography; (3) compression at topographic break, autobrecciation, lobe development and medium scale folding; (4) progressive deformation with stagnation, large-scale folding and re-folding; and (5) brittle deformation following flow termination. The complex array of structural elements observed within the Rocche Rosse lava flow facilitates comparisons to be made with actively deforming rhyolitic lava flows at the Chilean volcanoes of Chaitén and Cordón Caulle, offering a fluid dynamic and structural framework within which to evaluate our data.
AB - The Rocche Rosse lava flow marks the most recent rhyolitic extrusion on Lipari island (Italy), and preserves evidence for a multi-stage emplacement history. Due to the viscous nature of the advancing lava (108 to 1010 Pa s), indicators of complex emplacement processes are preserved in the final flow. This study focuses on structural mapping of the flow to highlight the interplay of cooling, crust formation and underlying slope in the development of rhyolitic lavas. The flow is made up of two prominent lobes, small (< 0.2 m) to large (> 0.2 m) scale folding and a channelled geometry. Foliations dip at 2–4° over the flatter topography close to the vent, and up to 30–50° over steeper mid-flow topography. Brittle faults, tension gashes and conjugate fractures are also evident across flow. Heterogeneous deformation is evident through increasing fold asymmetry from the vent due to downflow cooling and stagnation. A steeper underlying topography mid-flow led to development of a channelled morphology, and compression at topographic breaks resulted in fold superimposition in the channel. We propose an emplacement history that involved the evolution through five stages, each associated with the following flow regimes: (1) initial extrusion, crustal development and small scale folding; (2) extensional strain, stretching lineations and channel development over steeper topography; (3) compression at topographic break, autobrecciation, lobe development and medium scale folding; (4) progressive deformation with stagnation, large-scale folding and re-folding; and (5) brittle deformation following flow termination. The complex array of structural elements observed within the Rocche Rosse lava flow facilitates comparisons to be made with actively deforming rhyolitic lava flows at the Chilean volcanoes of Chaitén and Cordón Caulle, offering a fluid dynamic and structural framework within which to evaluate our data.
KW - Rhyolite
KW - Blocky lava flow
KW - Folds
KW - High viscosity
KW - Deformation
KW - Obsidian
U2 - 10.1007/s00445-018-1222-4
DO - 10.1007/s00445-018-1222-4
M3 - Article
VL - 80
SP - 1
EP - 19
JO - Bulletin of Volcanology
JF - Bulletin of Volcanology
SN - 1432-0819
IS - 5
M1 - 48
ER -