Amagmatic extension and tectonic denudation in the Kizildag Ophiolite, southern Turkey: implications for the evolution of Neotethyan oceanic crust

Abstract

Structures and contact relationships in the ophiolite are interpreted to have resulted from a period of tectonic extension and denudation following magmatic construction of ophiolitic crust. A low-angle fault dipping southeast toward the axial graben is interpreted to have accommodated tectonic extension at crustal levels and uplift and exposure of upper mantle rocks. The authors envision a model of asymmetric extension, analogous to that suggested for magma starved segments of the Mid-Atlantic Ridge around 23°N latitude. The Kizildag ophiolite represents a fragment of a Neotethyan oceanic spreading center that was subsequently emplaced onto the passive margin of Arabia possibly by conversion of a ridge-parallel normal fault to a thrust fault (incipient subduction zone?) as a result of a change in relative plate motion in late Cretaceous time. -from Authors