Numerical simulation of strain within lava domes

A new analytical and numerical method is presented to assess 3D deformation within lava domes. The method allows any simultaneous combination of strain components, even that of a pure shear and six elementary simple shear components. The methodʹs practical use is presented. Model results provide the following information for lava dome strain patterns: in the upper part of a dome stretching is perpendicular to flow direction and in the lower part it is parallel. Flinn parameter values indicate a flattening strain ellipsoid through the dome, except in a small zone in the centre, where it is a constriction ellipsoid.