Experimental determination of the rheology and acoustic emissions of Colima (Mexico) dome lavas

• Applicant: Professor Dr. Yan Lavallée
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2010 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 165490031

The increasingly alarming volcanic crisis at volcán de Colima (Mexico) requires imminent, thorough investigation of lava’s seismogenic properties. Domebuilding eruptions such as that of Colima commonly exhibit acceleration of the strain rate and seismicity before erupting explosively. To date, eruption forecast models employing the material failure forecasting method (FFM) have been based solely on the seismicity of the country rock. This is despite our knowledge that lava rheology and deformation rate dictate lava responses and thus whether eruptions are effusive of explosive. Understanding of the ductile-brittle transition in dome lavas may well contain the key to an adequate description of dome growth and stability. A series of rheological and acoustic tests is proposed to systematically characterize the seismogenic character of dome lavas across the ductile-brittle transition. This work aims (1) to explain the viscoelastic nature of natural lavas hosting abundant crystals and bubbles, and (2) to describe fracturing mechanisms across this ductile-brittle transition. In a second tense, this work will (3) assess the conditions under which the FFM can be used for lavas, with the goal of (4) generating a framework for explosive eruption forecasting of dome-building eruptions.

• DFG Programme: Research Grants
• Participating Persons: Professor Dr. Donald Bruce Dingwell; Dr. Kai-Uwe Hess; Dr. Joachim Wassermann