The Role of Fault Permeability Evolution on Groundwater Flow Patterns and Brine Flushing within the Papuan Fold Belt

The evolution of subsurface fluid flow patterns within fold belts is a function of stratigraphic juxtaposition, fault permeability evolution, topography, tectonic stresses, and erosion. Here, we consider the relative importance of juxtaposition of aquifers/confining units verse the role of fault permeability evolution through time and laterally along in controlling groundwater flow patterns. We used the structural restoration software package 2DMove at 1 million year increments along a northwest-southeast cross-sectional transect which cuts through the Muller anticline and balanced cross sections of Hill (1991) along strike. Permeability evolution of the thrust faults is calculated using the algorithm of Bense and Person (2006). Finite element representations of fluid flow, heat, and brine transport are then used to determine the timing and locus of brine are flushing from the Papuan fold belt out into the Fly Plateform. Our analysis has implications for hydrodynamically tilted oil-water contacts and oil flushing from structures. Evidence of brine flushing is derived from present-day salinity patterns and fluid inclusion data from the Toro Sandstone.