The parallel lines along the top of this section of rock were made using the quarry pick. This is one side of a channel originally cut along the back of a block, into which the wedge holes below were cut.
Wedges were used to split the rock which would have occupied the area in front of this row of wedges holes away from the bedrock. Unfortunately for the quarrymen a natural fissure in the stone meant that the block broke away unevenly from the bedrock, leaving the projecting rock in the bottom left of this image in place.
This detail is from one of the more than seventy individual extraction points which constitute the so-called City Quarries at Aphrodisias, located roughly 2 km north of the city. White and grey marbles were quarried in this area.