Wadi Rahma dykes

Three generations of dykes in Wadi Rahma. Cordierite bearing gneiss (800Ma) at the mountain top is intruded by granite (610-615Ma) with synintrusive gently dipping mafic veins (red arrow). This is in turn invaded by composite dykes (green arrow, 570-580Ma) and steep dolerite dykes (blue arrow, 550 Ma). Marker indicates viewpoint of photographer, looking east
PhotoID362

Photograph: Cees Passchier, Ghaleb Jarrar