Geological controls on fault relay zone scaling

Abstract

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Conceptual and numerical models of a tectonically-controlled geothermal system: a case study of the Euganean Geothermal System, Northern Italy

“…Peacock and Sanderson 1994;Trudgill and Cartwright 1994;Peacock and Sanderson 1995;Long and Imber 2011), and in general interaction zones of faults, are potential sites of hydrothermal fluid flow because they are characterized by high stress, which increases the local fracturing and permeability (Curewitz and Karson 1997;Ferrill and Morris 2001;Rotevatn et al 2007). The EGF coincides with the breached relay ramp of the SVFS (Figs 2C and 2D).…”

Extension parallel to the rift zone during segmented fault growth: application to the evolution of the NE Atlantic

“…For instance, worldwide catalogues of relay zone geometry have demonstrated a power-law scaling relationship that covers approximately 8 orders of magnitude (e.g. Peacock, 2003;Long and Imber, 2011). Evidence for heave gradients and locally non-coaxial strains are described on a separation scale of tens of kilometres in the East African Rift (e.g.…”

“…Normal faults comprise multiple discontinuous, non-collinear segments, with overlaps and segment linkage forming characteristic stepping geometries on a broad range of scales (e.g. Cartwright et al, 1996;Peacock et al, 2000;Acocella et al, 2005;Long and Imber, 2011;Henstra et al, 2015). Fault growth models have been derived using natural examples and numerical, or scaled-analogue modelling techniques, in which normal faults grow through stages in which discontinuous segments interact and link across relay zones to form composite structures with fault displacement deficits initially accommodated by soft-linkage rotation and/or material folding (e.g.…”

“…Segmentation is a feature common to all scales of faults and fault development (e.g. Walsh et al, 2003;Long and Imber, 2011) and the conservation of regional strain across networks of discontinuous segments has…”

“…Peacock andSanderson, 1991, 1994;Childs et al, 1995;Long and Imber, 2010), and depending on the degree of overlap and separation of individual segments, may lead to different styles of deformation (e.g. Tentler and Acocella, 2010;Long and Imber, 2011;Childs et al, 2017) ( Fig. 1a, b).…”