The viscosity of hydrous dacitic liquids: implications for the rheology of evolving silicic magmas

  title={The viscosity of hydrous dacitic liquids: implications for the rheology of evolving silicic magmas},
  author={Alan G. Whittington and Bridget M. Hellwig and Harald Behrens and Bastian Joachim and Andr{\'e} Stechern and Francesco Vetere},
  journal={Bulletin of Volcanology},
The viscosity of a series of six synthetic dacitic liquids, containing up to 5.04 wt% dissolved water, was measured above the glass transition range by parallel-plate viscometry. The temperature of the 1011 Pa s isokom decreases from 1065 K for the anhydrous liquid, to 864 K and 680 K for water contents of 0.97 and 5.04 wt% H2O. Including additional measurements at high temperatures by concentric-cylinder and falling-sphere viscometry, the viscosity (η) can be expressed as a function of… 
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