Volatile dilution during magma injections and implications for volcano explosivity

Show simple item record

dc.identifier.uri http://dx.doi.org/10.15488/2646
dc.identifier.uri http://www.repo.uni-hannover.de/handle/123456789/2672
dc.contributor.author Cassidy, Mike
dc.contributor.author Castro, Jonathan M.
dc.contributor.author Helo, Christoph
dc.contributor.author Troll, Valentin R.
dc.contributor.author Deegan, Frances M.
dc.contributor.author Muir, Duncan
dc.contributor.author Neave, David A.
dc.contributor.author Mueller, Sebastian P.
dc.date.accessioned 2018-01-19T12:03:37Z
dc.date.available 2018-01-19T12:03:37Z
dc.date.issued 2016
dc.identifier.citation Cassidy, M.; Castro, J.M.; Helo, C.; Troll, V.R.; Deegan, F.M. et al.: Volatile dilution during magma injections and implications for volcano explosivity. In: Geology 44 (2016), Nr. 12, S. 1027-1030. DOI: https://doi.org/10.1130/G38411.1
dc.description.abstract Magma reservoirs underneath volcanoes grow through episodic emplacement of magma batches. These pulsed magma injections can substantially alter the physical state of the resident magma by changing its temperature, pressure, composition, and volatile content. Here we examine plagioclase phenocrysts in pumice from the 2014 Plinian eruption of Kelud (Indonesia) that record the progressive capture of small melt inclusions within concentric growth zones during crystallization inside a magma reservoir. High-spatial-resolution Raman spectroscopic measurements reveal the concentration of dissolved H2O within the melt inclusions, and provide insights into melt-volatile behavior at the single crystal scale. H2O contents within melt inclusions range from ?0.45 to 2.27 wt% and do not correlate with melt inclusion size or distance from the crystal rim, suggesting that minimal H2O was lost via diffusion. Instead, inclusion H2O contents vary systematically with anorthite content of the host plagioclase (R2 = 0.51), whereby high anorthite content zones are associated with low H2O contents and vice versa. This relationship suggests that injections of hot and H2O-poor magma can increase the reservoir temperature, leading to the dilution of melt H2O contents. In addition to recording hot and H2O-poor conditions after these injections, plagioclase crystals also record relatively cold and H2O-rich conditions such as prior to the explosive 2014 eruption. In this case, the elevated H2O content and increased viscosity may have contributed to the high explosivity of the eruption. The point at which an eruption occurs within such repeating hot and cool cycles may therefore have important implications for explaining alternating eruptive styles. eng
dc.language.iso eng
dc.publisher Boulder : Geological Society of America
dc.relation.ispartofseries Geology 44 (2016), Nr. 12
dc.rights CC BY 3.0
dc.rights.uri https://creativecommons.org/licenses/by/3.0/
dc.subject Asia eng
dc.subject inclusions eng
dc.subject Far East eng
dc.subject igneous rocks eng
dc.subject fluid inclusions eng
dc.subject pumice eng
dc.subject pyroclastics eng
dc.subject Indonesia eng
dc.subject Java eng
dc.subject magmas eng
dc.subject volcanic rocks eng
dc.subject.ddc 550 | Geowissenschaften ger
dc.title Volatile dilution during magma injections and implications for volcano explosivity
dc.type article
dc.type Text
dc.relation.issn 00917613
dc.relation.doi https://doi.org/10.1130/G38411.1
dc.bibliographicCitation.issue 12
dc.bibliographicCitation.volume 44
dc.bibliographicCitation.firstPage 1027
dc.bibliographicCitation.lastPage 1030
dc.description.version publishedVersion
tib.accessRights frei zug�nglich


Files in this item

This item appears in the following Collection(s):

Show simple item record

 

Search the repository


Browse

My Account

Usage Statistics