Giant Ravine in my Map

1
Hello friends,

I installed "ByzantineV5" and the terrain files and there is a giant ravine about 2 rows wide and 100 cells long along the border of my lower right most region. I reinstalled everyting and created a brand new database and the ravine shifted from a north-south orientation to an east-west orientation, but remains. I'm at a loss, I am ready to give up on this map but thought I'd ask about one last time... anyone know what this is?
cron