Internal fabric development in complex lava domes

Viscous lava extrusions were modeled using plaster of Paris with admixed magnetite dust which served as a tracer of the internal anisotropy of magnetic susceptibility fabric in model lava domes. Used analogue material showed pseudoplastic behavior and yield strength level proportional to increasing mixing ratio of plaster powder and water. A series of models ranging from simple gravity flows to complex lava domes showing combined endogenous and exogenous growth were created by intrusion of plaster into a sandbox. The similarity of model bodies is compared with natural lava domes on the basis of dynamic scaling analysis. Growth dynamics, exogenous growth and internal fabric development in natural lava domes is critically discussed using the experimental results.