Crocodile cracking.

This was one of a duo going down the street fixing pot holes. Apparently to fix a pothole you first need to square off the offending hole. This is what the guy is doing here with a pavement saw. Next the debris within this even cut was removed manually with a pick and shovel. The patching mix of hot bitumen was applied and compacted with a vibratory plate compactor. A liquid "tack" was then applied to seal the edges.
The duo then moved off, presumably to return next year.
Crocodile cracking is the term applied to the interlocking fatigue fractures that develop in the road surface and lead to its break-up and pothole formation.