ABSTRACT

In this paper, a new approach to calculating and restoring the effects of physical compaction in subsalt units is presented. The loading of subsalt units and associated physical compaction is controlled by a combination of suprasalt sedimentation and salt movements. Here it is proposed that the change in load affecting the subsalt units is equivalent to the thickness between paleosurfaces of the basin (regional levels) reconstructed for successive stratigraphic horizons. This is in contrast to suprasalt units, where the changes in load are equivalent to the thickness of the stratigraphic unit. The new approach is integrated into a complete workflow for sequential restoration in a salt basin, which involves (1) removing the effects of physical compaction in suprasalt units, (2) reconstructing the paleosurfaces of the basin (regional level), (3) restoring faults, (4) unfolding to the reconstructed regional level to restore the effects of salt movement in the suprasalt units, (5) reconstructing the change in load affecting subsalt units and restoring the associated physical compaction, and (6) restoring any isostasy and postrift thermal subsidence. Results obtained using this workflow are compared with other methodologies to assess the differences in subsalt sediment thickness and structural configurations. These results suggest that the workflow proposed in this paper will improve the accuracy of sequential restoration of subsalt hydrocarbon plays, allowing their structural configurations through time to be more accurately quantified, and will ultimately reduce the risks in developing subsalt resources.

You do not currently have access to this article.