KINE3D: a New 3d Restoration Method Based on a Mixed Approach Linking Geometry and Geomechanics

Abstract : We developed a new methodology for 3D restoration by coupling a geometric modelling software and a mechanical finite-element code. This method allows the geologist to impose the displacement on the main faults in order to get an adequate restored geometry and to compute the 3D strain and stress fields within the main blocks based on the unfolding with the mechanical approach. Complex meshing of the solid take into account heterogeneities due to the layering and facies variation. Results are discussed on compressive and extensional contexts, as well as in backward and forward approaches. The compressive case is illustrated by the restoration of a faulted anticline with massive sand and shaly beds. This case has been also restored with 2D surface unfolding processes and we will compare the information that geologists may get from the various methods. The second case concerns the deformation, in a gravity gliding context, of a sandy channel embedded into a shaly matrix. The mixed approach allows to quantify the reorientation of the stress field on the sand/shale boundary.