Intraplate strike-slip deformation belts
Intraplate strike-slip deformation belts are typically steeply-dipping structures that develop in both oceanic and continental lithosphere where they form some of the largest and most spectacular discontinuities found on Earth. In both modern and ancient continental settings, intraplate strike slip deformation belts are of major importance in accommodating horizontal displacements where they additionally form very persistent zones of weakness that substantially influence the rheological behaviour of the lithosphere over very long time periods (up to 1 Ga or more). These deformation zones provide a fundamental geometric, kinematic and dynamic link between the more rigid plate-dominated tectonics of the oceans and the non-rigid, complex behaviour of the continents. During convergence, they help to transfer major displacements deep into the plate interiors. During divergence, they act as transfer zones that segment rifts, passive continental margins and, ultimately, oceanic spreading ridges. Such belts are also of great economic importance, controlling the location of many destructive earthquakes, offshore and onshore hydrocarbon deposits and metalliferous ore deposits. In the oceans, intraplate strike-slip movements are relatively minor along transform-related fracture zones, but there are an increasing number of documented examples that may reflect spatial and temporal variations in spreading rate along individual active ridge segments.
Figures & Tables
Intraplate Strike-Slip Deformation Belts
Intraplate strike-slip deformation belts are common tectonic features, particularly at convergent plate boundaries, where they are produced by both oblique convergence and continental indentation. These lithosphere-scale structures, which also occur in other geodynamic environments such as passive margins, are characterized by complex structural architectures, by the occurrence of large earthquakes, and by the fast uplift and/or subsidence of localized crustal sectors.
Intraplate strike-slip belts can also control the ascent and emplacement of deeply sourced magmas. In some cases, intraplate strike-slip belts link with oceanic fracture zones and transform faults, transferring transform shear from the ridges to the interior of the plates. This evidence has an important impact of the classical concept of transform faulting.
This volume contains 13 papers from an international field of contributors. Studies of intraplate strike-slip deformation belts from Africa, Antarctica, Eurasia, North America and South America are included.