Spreading-induced faulting and fracturing of oceanic crust: examples from the Sheeted Dyke Complex of the Troodos ophiolite, Cyprus

Abstract

Abstract Detailed mapping and structural analysis of the Sheeted Dyke Complex of the Troodos ophiolite, Cyprus, has provided valuable insight into the extensional processes active during the formation of oceanic crust. Oceanic extension is essentially accommodated by: (1) a dense network of small-scale normal faults (metric to several metres spacing of the fault planes) which migrate upwards in time and space through the Sheeted Dyke Complex; and (2) larger-scale normal faults (decametric spacing of the fault planes) which detach into sub-horizontal shear zones and which cause rotation of overlying dyke packets. Geometric models are derived from these structures which differ markedly from the known models of continental extension. In particular, a new ramp/flat model of normal faulting is proposed for the most frequently occurring type of small-scale faults.