Print this pageTechniques for 3Dimensional Validation and Kinematic Modelling of Salt
GRIFFITHS, PAUL A., STEPHANIE J. KAPE, ALAN D. GIBBS, ROSALIND J. RUSSELL
Computer restoration of salt structures using 3D volume balancing can determine the location of palaeo-salt catchment areas, the rate of migration and structure development and the influence of regional tectonics on both the overburden and the salt. These new methodologies have been derived from the analysis of salt structures in the UKOS and onshore Europe. 3D visualisation of a salt structure allows its morphological classification into reactive, active and passive diapirism and lateral salt tongues, thus giving a basic geohistory model. From this, the most appropriate algorithms for restoration may be determined. A variety of algorithms may be used in restoring any one structure (including radial structures and lateral intrusions) and the salt volume through time can be measured. Restoration assumes that salt movement generates a sedimentary response, either as basin formation or uplift and thinning. By fixing the basement during restoration, the migration of the salt 'back' into the withdrawal basins can be reconstructed, and the timing of salt movement constrained. Monitoring volume during restoration provides a measure of salt volume lost from the model through time. Separate restorations of the overburden and basement may highlight any discrepancies within the structural model, and any regional tectonic influence. Salt restoration provides a method of reducing technical risk by validating the structure interpretation. The kinematic model derived from the restoration process can give important new information on trap development and factors influencing charge and spill in the structure.