Buoyancy-driven invasion percolation with migration and fragmentation

A modified invasion percolation model that includes migration and fragmentation processes is presented. Fluid clusters were formed using the ordinary gravity invasion percolation model. Migration of fluid clusters was driven by buoyancy forces. The fluid formed a fragmented structure oriented in the direction of the buoyancy forces. The fragments formed temporary ''pipelines'' through which fluid was transported from the source to the tip of the structure. In the presence of a trapping rule the fragmented structure could bifurcate. The structures obtained in the simulations in two dimensions can be described in terms of standard percolation and invasion percolation.