Structural pattern of Pan-African rocks around Moyale, southern Ethiopia

Abstract Late Precambrian rocks exposed around Moyale are part of the Mozambique Orogenic Belt. Field mapping indicates that post-Baragoian (650 Ma) tectonic events have overprinted earlier tectonic fabrics of metasediment-metavolcanic rocks and intruded gabbroic-granitic plutons outcropping in the region. The main regional structure is defined by generally north-trending, upright, doubly plunging, tight to isoclinal folds (Barsaloian event: 580 Ma). Later events produced a large scale fold with a northeast-southwest axial trace in the central-western region of the map area, and north-south to northwest-southeast shear orientations. It is interpreted that northwest-southeast shears activated thrusting and that the region can be interpreted as a “flower structure” in section.