Erg Chech, Timbuktu district, Mali
Daytime, 2 or 3 July 2007
The flow lines on the lee side of this stone are deposits that have come over the fusion crust lip. They begin at the edge of the face and proceed downstream toward lower pressure. The set at the top of this picture is largely depositional. The set from the left is slightly different.
Closer view of the set at the top. Molten material was deposited on the lip and down onto the lower surface beyond.
The material that formed the flow line that extends across this picture came from the breach in the rollover lip at the arrow. Close inspection shows that hot material eroded the lip and a pit to the right of it, flowed a short distance, branched and deposited material along several courses, one of them being quite long.
Very close view of the breach in the rollover lip and the area just downstream of it.
