Relazione su invito
Modelling changes in the effusion rate of lava flows.
Effusion rate is a crucial parameter in lava flows, its time history controlling the flow duration and length. A model is presented ascribing the changes in effusion rate to processes occurring in the volcanic conduit. The conduit is modelled as a right, elliptical cylinder, representing a wide range of section shapes. The mechanical erosion of the conduit wall and the decreasing pressure gradient in the conduit can reproduce the observed global change of effusion rate during an eruption. Short-term oscillations in the effusion rate may be due to elastic deformation of the wall associated with pressure changes in the conduit.