Two-dimensional inverse modeling of sedimentary basin subsidence

Recently developed mathematical models of subsidence in extensional basins provide a good basis for forward modeling. However, the large number of par ameters to be specified by the user makes it difficult not only to do the m odeling itself, but also to judge the meaning of the results. We present a new method for automatic searching of the best-fitting parameter set of a 2 D basin formation model. Weighted goal functions are used in the minimizati on process by the inverse problem solver algorithm. The nominal parameter s et in the present case includes profiles of the crustal and subcrustal thin ning factors, and the level of lithosphere necking. The method was tested o n synthetic data with parameters that were perturbed beforehand. With some restrictions, the algorithms are capable of resolving such perturbations. T he inversion technique has been applied to two profiles crossing the Dniepe r-Donets Basin (Ukraine). The crustal thinning factors obtained argue for a scissors-like style of basin opening. High subcrustal thinning values are necessary in order to explain the abnormally thick Carboniferous section in the basin. These values should be treated as cumulative ones due to the cu rrently unresolvable influence of other rifting-related processes, particul arly phase transitions.