The Neoproterozoic Mozambique Belt in the Gol Mountains (N Tanzania): Structural Analysis of Amphibolite and Granulite‐Facies Nappe Tectonites From a Crustal Orogenic Channel

Abstract A structural analysis of the Gol Mountains of North Tanzania is presented in which we identify and characterize a sheet‐like deformation‐localization zone of regional scale. Syn‐metamorphic rock‐deformation within the localization zone gave rise to widespread tectonite development under high‐T in lower‐mid crustal realms. Regional foliations and mineral/stretching lineations, and associated non‐coaxial mineral petrofabrics can be correlated with ductile flow shear planes. At the macro‐scale these structures are genetically connected with tangential movement zones involving large a‐type and sheath folds, thrusts and ductile shear zones, and hydrothermal quartz megaveins plastically deformed. The dimension of the area affected by this structural style is c. 30 km across the Mozambique Belt and >50 km parallel to it. The associated tectonic displacements likely attained several tens of km in the context of an overall W‐directed tectonic vergence transversal to the Mozambique Belt orogenic trend. It is interpreted as a segment of a mid‐lower crustal orogenic channel active during late Ediacaran amalgamation of the Congo‐Tanzania Archean Craton (and its discontinuous fringe of Paleoproterozoic and Mesoproterozoic orogens) with the amalgamated arcs and terranes of the Arabian‐Nubian Shield.