Chemical interdiffusion between Na-series tephritic and phonolitic melts with different H2O content, temperature, and oxygen fugacity values

Research output: Contribution to journalArticleResearchpeer review

Authors

External Research Organisations

  • Complutense University of Madrid (UCM)
View graph of relations

Details

Original languageEnglish
Pages (from-to)623–640
Number of pages18
JournalEuropean Journal of Mineralogy
Volume36
Issue number4
Publication statusPublished - 23 Aug 2024

Abstract

The diffusive exchange of major elements in Na-series tephrite–phonolite diffusion couples with compositions relevant to the Canary Islands magmatism was determined at 300 MPa and variable H 2O concentrations (0.3 wt % to 3.3 wt %), temperatures (1150 to 1300 °C), and fO 2 levels (NNO−1.5 to NNO+1.7). Composition-dependent effective binary diffusion coefficients were determined from concentration–distance profiles. Results show a wide range of diffusivities for different cations, consistently following the sequence Na Al K ≥ Mg = Fe = Ca > Si > Ti, with a mild diffusivity contrast (0.2–0.8 log units) between tephritic and phonolitic melts. Na is the fastest component, with diffusivities falling ∼ 1.0 log units above those of Si for any given condition. An anomalously fast Al diffusion is observed, with D Al falling ∼ 0.4 log units above Si and ∼ 0.6 log units below Na, suggesting a prevalence of Al–alkali coupling across our range of run conditions. The relationships between log D and H 2O content in melt for all cations in an intermediate composition are strongly nonlinear and can be fitted using an exponential function with a convergence in diffusion coefficients for different temperatures with increasing H 2O content. Thus, Arrhenius analyses result in a decrease in activation energies from 222–293 kJ mol −1 at 1.7 wt % H 2O to 48–112 kJ mol −1 at 3.0 wt % H 2O. These results provide new data on chemical interdiffusion in highly alkaline Na-rich melts and suggest that H 2O content plays a key role in increasing the chemical efficiency of magma mixing at low temperatures. The obtained dataset is used to test chemical controls of magma mixing in the El Abrigo ignimbrite, Tenerife, where banded pumices involving basanitic–tephritic to phonolitic magmas are common in several compositionally bimodal ignimbrite units.

ASJC Scopus subject areas

Cite this

Chemical interdiffusion between Na-series tephritic and phonolitic melts with different H2O content, temperature, and oxygen fugacity values. / González-García, Diego; Pohl, Florian; Marxer, Felix et al.
In: European Journal of Mineralogy, Vol. 36, No. 4, 23.08.2024, p. 623–640.

Research output: Contribution to journalArticleResearchpeer review

González-García D, Pohl F, Marxer F, Krasheninnikov S, Almeev R, Holtz F. Chemical interdiffusion between Na-series tephritic and phonolitic melts with different H2O content, temperature, and oxygen fugacity values. European Journal of Mineralogy. 2024 Aug 23;36(4):623–640. doi: 10.5194/ejm-36-623-2024
González-García, Diego ; Pohl, Florian ; Marxer, Felix et al. / Chemical interdiffusion between Na-series tephritic and phonolitic melts with different H2O content, temperature, and oxygen fugacity values. In: European Journal of Mineralogy. 2024 ; Vol. 36, No. 4. pp. 623–640.
Download
@article{b1bac6eab2e6436fb6f41099921e9f57,
title = "Chemical interdiffusion between Na-series tephritic and phonolitic melts with different H2O content, temperature, and oxygen fugacity values",
abstract = "The diffusive exchange of major elements in Na-series tephrite–phonolite diffusion couples with compositions relevant to the Canary Islands magmatism was determined at 300 MPa and variable H 2O concentrations (0.3 wt % to 3.3 wt %), temperatures (1150 to 1300 °C), and fO 2 levels (NNO−1.5 to NNO+1.7). Composition-dependent effective binary diffusion coefficients were determined from concentration–distance profiles. Results show a wide range of diffusivities for different cations, consistently following the sequence Na Al K ≥ Mg = Fe = Ca > Si > Ti, with a mild diffusivity contrast (0.2–0.8 log units) between tephritic and phonolitic melts. Na is the fastest component, with diffusivities falling ∼ 1.0 log units above those of Si for any given condition. An anomalously fast Al diffusion is observed, with D Al falling ∼ 0.4 log units above Si and ∼ 0.6 log units below Na, suggesting a prevalence of Al–alkali coupling across our range of run conditions. The relationships between log D and H 2O content in melt for all cations in an intermediate composition are strongly nonlinear and can be fitted using an exponential function with a convergence in diffusion coefficients for different temperatures with increasing H 2O content. Thus, Arrhenius analyses result in a decrease in activation energies from 222–293 kJ mol −1 at 1.7 wt % H 2O to 48–112 kJ mol −1 at 3.0 wt % H 2O. These results provide new data on chemical interdiffusion in highly alkaline Na-rich melts and suggest that H 2O content plays a key role in increasing the chemical efficiency of magma mixing at low temperatures. The obtained dataset is used to test chemical controls of magma mixing in the El Abrigo ignimbrite, Tenerife, where banded pumices involving basanitic–tephritic to phonolitic magmas are common in several compositionally bimodal ignimbrite units.",
author = "Diego Gonz{\'a}lez-Garc{\'i}a and Florian Pohl and Felix Marxer and Stepan Krasheninnikov and Renat Almeev and Fran{\c c}ois Holtz",
note = "Publisher Copyright: Copyright: {\textcopyright} 2024 Diego Gonza´lez-Garci´a et al.",
year = "2024",
month = aug,
day = "23",
doi = "10.5194/ejm-36-623-2024",
language = "English",
volume = "36",
pages = "623–640",
number = "4",

}

Download

TY - JOUR

T1 - Chemical interdiffusion between Na-series tephritic and phonolitic melts with different H2O content, temperature, and oxygen fugacity values

AU - González-García, Diego

AU - Pohl, Florian

AU - Marxer, Felix

AU - Krasheninnikov, Stepan

AU - Almeev, Renat

AU - Holtz, François

N1 - Publisher Copyright: Copyright: © 2024 Diego Gonza´lez-Garci´a et al.

PY - 2024/8/23

Y1 - 2024/8/23

N2 - The diffusive exchange of major elements in Na-series tephrite–phonolite diffusion couples with compositions relevant to the Canary Islands magmatism was determined at 300 MPa and variable H 2O concentrations (0.3 wt % to 3.3 wt %), temperatures (1150 to 1300 °C), and fO 2 levels (NNO−1.5 to NNO+1.7). Composition-dependent effective binary diffusion coefficients were determined from concentration–distance profiles. Results show a wide range of diffusivities for different cations, consistently following the sequence Na Al K ≥ Mg = Fe = Ca > Si > Ti, with a mild diffusivity contrast (0.2–0.8 log units) between tephritic and phonolitic melts. Na is the fastest component, with diffusivities falling ∼ 1.0 log units above those of Si for any given condition. An anomalously fast Al diffusion is observed, with D Al falling ∼ 0.4 log units above Si and ∼ 0.6 log units below Na, suggesting a prevalence of Al–alkali coupling across our range of run conditions. The relationships between log D and H 2O content in melt for all cations in an intermediate composition are strongly nonlinear and can be fitted using an exponential function with a convergence in diffusion coefficients for different temperatures with increasing H 2O content. Thus, Arrhenius analyses result in a decrease in activation energies from 222–293 kJ mol −1 at 1.7 wt % H 2O to 48–112 kJ mol −1 at 3.0 wt % H 2O. These results provide new data on chemical interdiffusion in highly alkaline Na-rich melts and suggest that H 2O content plays a key role in increasing the chemical efficiency of magma mixing at low temperatures. The obtained dataset is used to test chemical controls of magma mixing in the El Abrigo ignimbrite, Tenerife, where banded pumices involving basanitic–tephritic to phonolitic magmas are common in several compositionally bimodal ignimbrite units.

AB - The diffusive exchange of major elements in Na-series tephrite–phonolite diffusion couples with compositions relevant to the Canary Islands magmatism was determined at 300 MPa and variable H 2O concentrations (0.3 wt % to 3.3 wt %), temperatures (1150 to 1300 °C), and fO 2 levels (NNO−1.5 to NNO+1.7). Composition-dependent effective binary diffusion coefficients were determined from concentration–distance profiles. Results show a wide range of diffusivities for different cations, consistently following the sequence Na Al K ≥ Mg = Fe = Ca > Si > Ti, with a mild diffusivity contrast (0.2–0.8 log units) between tephritic and phonolitic melts. Na is the fastest component, with diffusivities falling ∼ 1.0 log units above those of Si for any given condition. An anomalously fast Al diffusion is observed, with D Al falling ∼ 0.4 log units above Si and ∼ 0.6 log units below Na, suggesting a prevalence of Al–alkali coupling across our range of run conditions. The relationships between log D and H 2O content in melt for all cations in an intermediate composition are strongly nonlinear and can be fitted using an exponential function with a convergence in diffusion coefficients for different temperatures with increasing H 2O content. Thus, Arrhenius analyses result in a decrease in activation energies from 222–293 kJ mol −1 at 1.7 wt % H 2O to 48–112 kJ mol −1 at 3.0 wt % H 2O. These results provide new data on chemical interdiffusion in highly alkaline Na-rich melts and suggest that H 2O content plays a key role in increasing the chemical efficiency of magma mixing at low temperatures. The obtained dataset is used to test chemical controls of magma mixing in the El Abrigo ignimbrite, Tenerife, where banded pumices involving basanitic–tephritic to phonolitic magmas are common in several compositionally bimodal ignimbrite units.

UR - http://www.scopus.com/inward/record.url?scp=85202181795&partnerID=8YFLogxK

U2 - 10.5194/ejm-36-623-2024

DO - 10.5194/ejm-36-623-2024

M3 - Article

VL - 36

SP - 623

EP - 640

JO - European Journal of Mineralogy

JF - European Journal of Mineralogy

SN - 1617-4011

IS - 4

ER -

By the same author(s)