looks like the oil pan gasket broke in half and started to bulge out the side. the wear looks normal unless you had it off before and i didn't look like that before, its just years of road debris coming up and hitting the underside. i'd drain the oil, pull the pan, make sure all mating surface are flat, sand them if need be a bit, clean it all up REALLY good, RTV the oil pan(don't buy a gasket) and make sure you reinstall the two shorter bolt under the timing belt and torque them all to the proper lbs. It doesn't look all that serious or something to concern yourself with, just something you need to take care of quickly.