An effective inverse scheme that can be applied to complex 3-D hydrodynamic forward models has so far proved elusive. In this paper we investigate an interactive inverse methodology that may offer a possible way forward. The scheme builds on previous work in linking expert review of alternate output to rapid modification of input variables. This was tested using the SEDSIM 3-D stratigraphie forward-modelling program, varying nine input variables in a synthetic example. Ten SEDSIM simulations were generated, with subtle differences in input, and five dip sections (fences) were displayed for each simulation. A geoscientist ranked the lithological distribution in...