hi allynellis, wondering if it may be an afghan or tunisian stitch pattern?
i looked at a few different patterns, but couldn't quite find it.
perhaps if you look,,, then again you may know it is was an afghan hook used.
another idea would be to ask in a yarn store, as the people there do know a lot,
maybe they could post a photo on a bulletin board if they don't recognize it.
certainly is a mystery, good luck.