Deformation of salt structures by ice-sheet loading: insights into the controlling parameters from numerical modelling ...

• Main Authors: Lang, Jörg, Hampel, Andrea
• Format: Text
• Language: English
• Published: Berlin 2023
• Subjects: Finite-element modelling ABAQUS; Glaciation; Ice-sheet loading; Salt mechanics; Salt structures; Dewey Decimal Classification500 | Naturwissenschaften550 | Geowissenschaften; Ice Sheet
• Online Access: https://dx.doi.org/10.15488/15466; https://www.repo.uni-hannover.de/handle/123456789/15587

Subsurface salt flow is driven by differential loading, which is typically caused by tectonics or sedimentation. During glaciations, the weight of an ice sheet represents another source of differential loading. In salt-bearing basins affected by Pleistocene glaciations, such as the Central European Basin System, ice loading has been postulated as a trigger of young deformation at salt structures. Here, we present finite-element simulations (ABAQUS) with models based on a simplified 50-km long and 10-km-deep two-dimensional geological cross-section of a salt diapir subject to the load of a 300-m-thick ice sheet. The focus of our study is to evaluate the sensitivity of the model to material parameters, including linear and non-linear viscosity of the salt rocks and different elasticities. A spatially and temporarily variable pressure was applied to simulate ice loading. An ice advance towards the diapir causes lateral salt flow into the diapir and diapiric rise. Complete ice coverage leads to downward ...