Details
Original language | English |
---|---|
Pages (from-to) | 1-9 |
Number of pages | 9 |
Journal | Neues Jahrbuch fur Mineralogie, Abhandlungen |
Volume | 195 |
Issue number | 1 |
Early online date | Sept 2017 |
Publication status | Published - 1 Feb 2018 |
Abstract
H2O solubility has been experimentally investigated in pantelleritic glasses at 850 °C in the range 0.5-2.5 kbar. Using a synthetic glass analogue of pantelleritic magma from the Kenya Rift Valley (Ebu-1 in Scaillet & MacDonald 2006) as starting composition, the molar Na/(Na+K) ratio was varied from 0 (Ebu-C) to 0.66 (Ebu-B) and 1 (Ebu-N) at constant total alkali content. The compositional dependence of water solubility as function of Na/(Na+K) was mainly investigated at 850 °C in the pressure interval 0.5-1.5 kbar. H2O solubility in rhyolitic systems is strongly dependent on the Na/(Na+K) ratio (HOLTZ et al. 1995, VETERE et al. 2014), yet such effects for pantellerites are still poorly constrained. Our new results suggest that higher Na favours higher H2O solubility (determined by KFT measurements). This alkali effect has important implications also for other chemical and physical properties of pantelleritic melts such as viscosity (e.g. Stabile et al. 2016). Our new data demonstrate a nearly linear positive correlation between water solubility (wt%) and pressure between 0.5 and 1.5 kbar at 850 °C (slightly above the water-saturated liquidus of the starting composition mixed alkali Ebu-B). The results we present aim to enlarge the experimental water solubility dataset for alkali- and silica-rich melts in order to improve existing predictive models of H2O solubility and eruptive processes (e.g. magma ascent, saturation and degassing).
Keywords
- Alkali effect, Composition, Eruptive processes, Pantellerite, Pressure
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)
- Geochemistry and Petrology
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Neues Jahrbuch fur Mineralogie, Abhandlungen, Vol. 195, No. 1, 01.02.2018, p. 1-9.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - H2O solubility in pantelleritic melts
T2 - Pressure and alkali effects
AU - Stabile, Paola
AU - Radica, Francesco
AU - Bello, Marco
AU - Behrens, Harald
AU - Carroll, Michael R.
AU - Paris, Eleonora
AU - Giuli, Gabriele
N1 - Publisher Copyright: © 2017 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/2/1
Y1 - 2018/2/1
N2 - H2O solubility has been experimentally investigated in pantelleritic glasses at 850 °C in the range 0.5-2.5 kbar. Using a synthetic glass analogue of pantelleritic magma from the Kenya Rift Valley (Ebu-1 in Scaillet & MacDonald 2006) as starting composition, the molar Na/(Na+K) ratio was varied from 0 (Ebu-C) to 0.66 (Ebu-B) and 1 (Ebu-N) at constant total alkali content. The compositional dependence of water solubility as function of Na/(Na+K) was mainly investigated at 850 °C in the pressure interval 0.5-1.5 kbar. H2O solubility in rhyolitic systems is strongly dependent on the Na/(Na+K) ratio (HOLTZ et al. 1995, VETERE et al. 2014), yet such effects for pantellerites are still poorly constrained. Our new results suggest that higher Na favours higher H2O solubility (determined by KFT measurements). This alkali effect has important implications also for other chemical and physical properties of pantelleritic melts such as viscosity (e.g. Stabile et al. 2016). Our new data demonstrate a nearly linear positive correlation between water solubility (wt%) and pressure between 0.5 and 1.5 kbar at 850 °C (slightly above the water-saturated liquidus of the starting composition mixed alkali Ebu-B). The results we present aim to enlarge the experimental water solubility dataset for alkali- and silica-rich melts in order to improve existing predictive models of H2O solubility and eruptive processes (e.g. magma ascent, saturation and degassing).
AB - H2O solubility has been experimentally investigated in pantelleritic glasses at 850 °C in the range 0.5-2.5 kbar. Using a synthetic glass analogue of pantelleritic magma from the Kenya Rift Valley (Ebu-1 in Scaillet & MacDonald 2006) as starting composition, the molar Na/(Na+K) ratio was varied from 0 (Ebu-C) to 0.66 (Ebu-B) and 1 (Ebu-N) at constant total alkali content. The compositional dependence of water solubility as function of Na/(Na+K) was mainly investigated at 850 °C in the pressure interval 0.5-1.5 kbar. H2O solubility in rhyolitic systems is strongly dependent on the Na/(Na+K) ratio (HOLTZ et al. 1995, VETERE et al. 2014), yet such effects for pantellerites are still poorly constrained. Our new results suggest that higher Na favours higher H2O solubility (determined by KFT measurements). This alkali effect has important implications also for other chemical and physical properties of pantelleritic melts such as viscosity (e.g. Stabile et al. 2016). Our new data demonstrate a nearly linear positive correlation between water solubility (wt%) and pressure between 0.5 and 1.5 kbar at 850 °C (slightly above the water-saturated liquidus of the starting composition mixed alkali Ebu-B). The results we present aim to enlarge the experimental water solubility dataset for alkali- and silica-rich melts in order to improve existing predictive models of H2O solubility and eruptive processes (e.g. magma ascent, saturation and degassing).
KW - Alkali effect
KW - Composition
KW - Eruptive processes
KW - Pantellerite
KW - Pressure
UR - http://www.scopus.com/inward/record.url?scp=85041896542&partnerID=8YFLogxK
U2 - 10.1127/njma/2017/0060
DO - 10.1127/njma/2017/0060
M3 - Article
AN - SCOPUS:85041896542
VL - 195
SP - 1
EP - 9
JO - Neues Jahrbuch fur Mineralogie, Abhandlungen
JF - Neues Jahrbuch fur Mineralogie, Abhandlungen
SN - 0077-7757
IS - 1
ER -