An investigation of salt tectonic structural styles in the Scotian Basin, offshore Atlantic Canada: 1. Comparison of observations with geometrically simple numerical models

Abstract

[1] Three primary salt tectonic structural styles of the Scotian Basin are compared with plane strain finite element models in order to investigate their origin. Here, we focus on simplified model salt basins with initial rectangular cross-sectional geometries and follow their evolution in the context of tectonic and parametric thermal subsidence and under various sedimentation regimes. Structural style A, an open-ended roho system with a synkinematic wedge, is reproduced by models including deltaic progradation and seaward spreading/ gliding of sediments above a salt detachment. Structural style B, a linked salt tectonic system with landward regional normal faults and allochthonous salt sheets climbing seaward over Late Cretaceous and Paleogene strata, is shown to be a consequence of early aggradation followed by progradation. Structural style C is characterized by salt diapirs and intervening minibasins and is reproduced by models with Rayleigh-Taylor instabilities requiring compaction driven density inversions, weak sediments, and initial perturbations of the overburden-salt interface.

Response of salt structures to ice-sheet loading: implications for ice-marginal and subglacial processes

“…However, with regard to the dimensions of the model section, the magnitude of the simulated load and the elapsed time, our models are several orders of magnitude smaller than those concerned with prograding sediment wedges (cf. Cohen and Hardy, 1996;Gemmer et al, 2004Gemmer et al, , 2005Albertz et al, 2010). The rates of ice-sheet advance are much faster than the progradation rates in sedimentary systems.…”

Salt tectonics at passive margins: Geology versus models

“…However, some salt basins could have initially been narrower e e.g. in Nova Scotia: possibly less than 100 km (Ings and Shimeld, 2006;Albertz et al, 2010). Other basins are obviously larger e e.g.…”

“…Different types of laboratory experiments (Cobbold and Szatmari, 1991;Gaullier et al, 1993;Mauduit et al, 1997Fort et al, 2004a,b;Brun andMauduit, 2008, 2009) or numerical modelling Albertz et al, 2010; have been carried out to characterise the structures produced by gliding above salt.…”

Evolution of rheologically heterogeneous salt structures: a case study from the NE Netherlands

“…Our knowledge of this domain is making some progress, because the internal layering of salt bodies can now be studied at high resolution using modern industrial 3-D seismic reflection data (Van Gent et al, 2011;Cartwright et al, 2012;Fiduk and Rowan, 2012;Jackson et al, 2014Jackson et al, , 2015. In addition, improvements in geomechanical modeling techniques has allowed major advances to be made (Chemia et al, 2008;Albertz et al, 2010;Albertz and Ings, 2012;Goteti et al, 2012;Li et al, 2012a, b).…”