oblique extension; oblique rifting; Taupo Rift; extension; transtension; passive margin; Atlantic margin; continental rifting; numerical modelling; analogue modelling
Zwaan Frank, Schreurs Guido, Rosenau Matthias (2019), Rift propagation in rotational versus orthogonal extension: Insights from 4D analogue models, in Journal of Structural Geology
Zwaan Frank, Schreurs Guido, Buiter Susanne J. H. (2019), A systematic comparison of experimental set-ups for modelling extensional tectonics, in Solid Earth
, 10(4), 1063-1097.
Zwaan Frank, Schreurs Guido, Adam Jürgen (2018), Effects of sedimentation on rift segment and transfer zone evolution in orthogonal and oblique extension settings: Insights from analogue models analysed with 4D X-ray computed tomography and digital, in Global and Planetary Change
Zwaan Frank, Schreurs Guido (2017), How oblique extension and structural inheritance influence rift segment interaction: Insights from 4D analog models, in Interpretation-a Journal of Subsurface Characterization
, 5(1), 119-138.
Zwaan Frank, Schreurs Guido, Naliboff John, Buiter Susanne J.H. (2016), Insights into the effects of oblique extension on Continental rift interaction from 3D analogue and numerical models, in Tectonophysics
, 693, 239-260.
1. 4D Analogue modelling of oblique extension: from continental rifting to passive margin formationDivergence of continental plates results in the formation of continental rifts and passive continental margins. Although intensely studied through geological and geophysical methods, in particular because of their hydrocarbon potential, the 3D geometries and fault styles of rifts and passive margins and the processes that have led to their present-day geometry remain poorly understood. In our opinion, a comprehensive understanding of the formation of rifts and margins needs to come from combining observations of their present-day structure with results of analogue and numerical modelling studies. Most rifts and passive margins have experienced oblique relative motion during at least part of their evolution and in this proposal we focus on oblique divergence of rifts and passive margins. The primary objective of this proposal is to determine how oblique divergence affects the geometry, faulting style and surface evolution of continental rifts and passive margins. To do so, we will build 3D analogue transtension models. The specific objectives of the scaled brittle-viscous analogue modelling experiments are to assess the following parameters that are generally considered to play an important role on the 3D geometry of rifts and passive margins: (1) variations in divergence direction (from one experiment to the next); (2) variations in divergence rate (from one experiment to the next); (3) symmetric vs. asymmetric divergence; (4) variations in divergence direction and divergence rate during multi-phase rifting; (5) syn-extensional sedimentation (6) pre-existing heterogeneities (e.g., viscous weak zones or pre-cut faults in the brittle layers) (7) variations in divergence direction and rate along strike; (8) the role of irregular margin shapes. As analogue materials we will use well-characterised viscous silicones and brittle, granular materials such as quartz sand, corundum sand and microbeads. We will analyse the evolution of our analogue models by X-ray CT analysis, which will allow us to record and analyse their 4D (3D geometry with time) evolution. In addition, we will analyse the spatial and temporal distribution of 3D strain accumulation in analogue models through digital image correlation techniques of X-ray CT images (with external collaborator Jürgen Adam). A full visualisation of the models and a full quantification of their strain will facilitate comparisons with 3D numerical models. We aim to gain new insights in the 3D character of natural rift systems and passive margins, such as the Taupo Rift, the East African rift system and the Atlantic margins, through analogue modelling. We will compare our results with selected numerical models run by external collaborators to the project (Susanne Buiter, Susan Ellis) and we will test our model results against observations from existing and on-going field and seismic studies of oblique rifts and passive margin (e.g. with external collaborator Pilar Villamor). Our results will improve the understanding of the evolution of oblique rifts and passive margins, a benefit that is important for hydrocarbon exploration, seismic hazard analysis and landscape analysis. The experimental results will deliver information on the physical parameters of deformation, which in turn may be transferred to natural settings to unravel the geometric and kinematic evolution during oblique rifting and passive margin formation.