Influence of rheologically weak layers on fault architecture: insights from analogue models in the context of the Northern Alpine Foreland Basin

Swiss Journal of Geosciences

Table 4 Overview of model parameters

Series	Model	Weak layer	Basal fault kinematics^a
Series A (reference models)	A1	Sand-only (without weak layer)	Pure normal dip-slip
	A2	Kinetic sand	Pure normal dip-slip
	A3	Quartz sand layer in viscous mixture^b	Pure normal dip-slip
	A4	Viscous layer	Pure normal dip-slip
Series B (models with a thick weak layer)^c	B1	Kinetic sand^c	Pure normal dip-slip
Series B (models with a thick weak layer)^c	B2	Viscous layer^c	Pure normal dip-slip
Series C (oblique slip & strike-slip models)	C1	Sand-only (without weak layer)	Dextral oblique normal slip
	C2	Viscous mixture	Dextral oblique normal slip
	C3	Sand-only (without weak layer)	Pure dextral strike-slip^d
	C4	Viscous mixture	Pure dextral strike-slip^d
Series D (fast fault slip models)^e	D1	Kinetic sand	Pure normal dip-slip
	D2	Viscous mixture	Pure normal dip-slip
	D3	Viscous mixture	Pure dextral strike-slip^d

^aFor definition of basal fault kinematics, see Sect. 3.1 and Fig. 3e
^bLayering includes a 4 mm thick quartz sand layer within the 1.2 cm thick weak layer
^cWeak layer is 2.4 cm thick and brittle quartz sand overburden is 4.1 cm thick to maintain a total model thickness of 6.5 cm
^dTotal basal fault slip in the strike-slip models is increased by a factor two, to 20.8 mm
^eBasal fault sliplip rate increased by a factor 10 to 104 mm/h (compared to standard 10.4 mm/h). Accordingly, the total model duration is reduced by a factor 10 as well