Polybaric fractional crystallisation of arc magmas: an experimental study simulating trans-crustal magmatic systems

Show simple item record

dc.identifier.uri http://dx.doi.org/10.15488/12509
dc.identifier.uri https://www.repo.uni-hannover.de/handle/123456789/12608
dc.contributor.author Marxer, Felix
dc.contributor.author Ulmer, Peter
dc.contributor.author Müntener, Othmar
dc.date.accessioned 2022-07-15T05:04:17Z
dc.date.available 2022-07-15T05:04:17Z
dc.date.issued 2022
dc.identifier.citation Marxer, F.; Ulmer, P.; Müntener, O.: Polybaric fractional crystallisation of arc magmas: an experimental study simulating trans-crustal magmatic systems. In: Contributions to Mineralogy and Petrology 177 (2022), Nr. 1, 3. DOI: https://doi.org/10.1007/s00410-021-01856-8
dc.description.abstract Crystallisation-driven differentiation is one fundamental mechanism proposed to control the compositional evolution of magmas. In this experimental study, we simulated polybaric fractional crystallisation of mantle-derived arc magmas. Various pressure–temperature trajectories were explored to cover a range of potential magma ascent paths and to investigate the role of decompression on phase equilibria and liquid lines of descent (LLD). Fractional crystallisation was approached in a step-wise manner by repetitively synthesising new starting materials chemically corresponding to liquids formed in previous runs. Experiments were performed at temperatures ranging from 1140 to 870 °C with 30 °C steps, and pressure was varied between 0.8 and 0.2 GPa with 0.2 GPa steps. For most fractionation paths, oxygen fugacity (fO2) was buffered close to the Ni-NiO equilibrium (NNO). An additional fractionation series was conducted at fO2 corresponding to the Re-ReO2 buffer (RRO ≈ NNO+2). High-pressure experiments (0.4–0.8 GPa) were run in piston cylinder apparatus while 0.2 GPa runs were conducted in externally heated pressure vessels. Resulting liquid lines of descent follow calc-alkaline differentiation trends where the onset of pronounced silica enrichment coincides with the saturation of amphibole and/or Fe–Ti–oxide. Both pressure and fO2 exert crucial control on the stability fields of olivine, pyroxene, amphibole, plagioclase, and Fe–Ti–oxide phases and on the differentiation behaviour of arc magmas. Key observations are a shift of the olivine–clinopyroxene cotectic towards more clinopyroxene-rich liquid composition, an expansion of the plagioclase stability field and a decrease of amphibole stability with decreasing pressure. Decompression-dominated ascent trajectories result in liquid lines of descent approaching the metaluminous compositional range observed for typical arc volcanic rocks, while differentiation trends obtained for cooling-dominated trajectories evolve to peraluminous compositions, similar to isobaric liquid lines of descent at elevated pressures. Experiments buffered at RRO provide a closer match with natural calc-alkaline differentiation trends compared to fO2 conditions close to NNO. We conclude that decompression-dominated fractionation at oxidising conditions represents one possible scenario for arc magma differentiation. © 2021, The Author(s). eng
dc.language.iso eng
dc.publisher Berlin ; Heidelberg : Springer
dc.relation.ispartofseries Contributions to Mineralogy and Petrology 177 (2022), Nr. 1
dc.rights CC BY 4.0 Unported
dc.rights.uri https://creativecommons.org/licenses/by/4.0/
dc.subject Arc magmatism eng
dc.subject Calc-alkaline rocks eng
dc.subject Fractional crystallisation eng
dc.subject Liquid line of descent eng
dc.subject Magma differentiation eng
dc.subject Polybaric differentiation eng
dc.subject calc alkaline rock eng
dc.subject clinopyroxene eng
dc.subject fractional crystallization eng
dc.subject fugacity eng
dc.subject magma eng
dc.subject time series analysis eng
dc.subject trajectory eng
dc.subject trend analysis eng
dc.subject.ddc 550 | Geowissenschaften ger
dc.title Polybaric fractional crystallisation of arc magmas: an experimental study simulating trans-crustal magmatic systems
dc.type Article
dc.type Text
dc.relation.essn 1432-0967
dc.relation.doi https://doi.org/10.1007/s00410-021-01856-8
dc.bibliographicCitation.issue 1
dc.bibliographicCitation.volume 177
dc.bibliographicCitation.firstPage 3
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


My Account

Usage Statistics