While searching a box of bu 2017p cents, there were a lot of them with this type of mark (all in the same location) on the reverse. What caused this?
The mint abusing dies caused that. From the pic it looks like the die was misaligned. Use this website and look for die misalignment errors. http://www.error-ref.com/ They have pictures of misaligned die atrocities. While your close-ups are very good, complete whole coin pics of both sides would help diagnose the problem.
