Modelling eruption cycles and decay of mud volcanoes

Recent debates about the eruptive behavior of mud volcanoes and their activation mechanisms have been driven particularly by the LUSI eruption in Indonesia that resulted in huge commercial and cultural damages. Numerical modeling of mud volcanoes, of which few exist, can provide insight into eruptive behavior and contribute to hazard evaluation. In this paper, we present a simple model to describe fluid escape from an underground reservoir through a conduit, extruded as a mud volcano at the surface. The governing equations result in oscillatory behavior, and we study the influence of changes in rheological properties of surrounding rock and fluid characteristics of the mud on extrusion dynamics. We focus on understanding long-term eruption behavior, flow cycles, and decay factors. Model results can be used to estimate the discharge rates and extruded volume from assumptions on the mud reservoir and conduit, or conversely, the reservoir or conduit properties from discharge rates.