The solubility of H 2 O in phonolitic melts

Other| June 01, 1997 The solubility of H2 O in phonolitic melts Michael R. Carroll; Michael R. Carroll Bristol University, Department of Geology, Bristol, United Kingdom Search for other works by this author on: GSW Google Scholar Jennifer G. Blank Jennifer G. Blank Carnegie Institution of Washington, United States Search for other works by this author on: GSW Google Scholar Author and Article Information Michael R. Carroll Bristol University, Department of Geology, Bristol, United Kingdom Jennifer G. Blank Carnegie Institution of Washington, United States Publisher: Mineralogical Society of America First Online: 02 Mar 2017 Online Issn: 1945-3027 Print Issn: 0003-004X Copyright © 1981 by the Mineralogical Society of America American Mineralogist (1997) 82 (5-6): 549–556. https://doi.org/10.2138/am-1997-5-615 Article history First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Michael R. Carroll, Jennifer G. Blank; The solubility of H2 O in phonolitic melts. American Mineralogist 1997;; 82 (5-6): 549–556. doi: https://doi.org/10.2138/am-1997-5-615 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyAmerican Mineralogist Search Advanced Search Abstract We have calibrated the IR spectroscopic technique for measurement of H2O dissolved in phonolitic glasses as hydroxyl and H2O molecules using manometric and weight-loss methods. The resulting molar absorptivity coefficients are 125−0.22+0.33 (for absorbance due to OH– at 4500 cm–1) and 1.10−0.10+0.12 (for absorbance due to molecular H2 O at 5200 cm–1). These values are similar to those previously determined for hydrous jadeitic glasses. We have applied our calibration to a new set of solubility experiments in which H2O and a natural phonolitic glass were equilibrated at near-liquidus temperatures (85–973 °C) and pressures of 191–1500 bars for periods of 38–272 h. We used a regular solution model to develop an equation of state for the solubility of H2O in phonolitic melts. Our experimental results demonstrate that H2O solubility is appreciably higher in phonolitic melts compared with basaltic and rhyolitic melts at the same pressures and near-liquidus temperatures; e.g., the solubility of H2O at 1000 bars is 4.9 wt% in phonolitic melt (850 °C), 4 wt% in rhyolitic (850 °C), and 3.2 wt% in basaltic (1200 °C) melts. The calculated partial molar volume of dissolved H2O in phonolitic melt (8.5 ± 2.5 cm3/mol) falls between that determined by similar methods for rhyolitic and basaltic melts, but we note that the significance of this number is unknown because speciation changes during quenching are not sufficiently well characterized. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.