Experimental models of strike-slip tectonics

We present a variety of models for strike-slip tectonics which represent a useful database for seismic interpreters and geologists. In pure strike-slip, the Riedel shear geometry is shown to depend on the initial stress state, interference of parallel basement faults and horizontal layering of the overburden. Above two parallel basement faults, a single wide or two separate fault zones may be mapped, depending on the depth of observation. In a heterogeneous layered sequence, upwards branching of Riedel shears occurs at layer interfaces. In oblique-slip faulting, the sense of vertical displacement and the geometry of the fault pattern are indicative of the tectonic regime. The degree of obliquity of the fault strike can be related to the ratio of dip-slip to strike-slip movement. In the case of relay structures, the ratio of the length of basement-fault offset to the thickness of the overburden controls the geometry of the fault pattern.