Oil Leak

[Chuck Pierce]

It seems I have a small oil leak. Question is where!
This not a big leak just is making a mess of the lower end of the engine 
and front cross member.
Do the oil pan bolts have a tendency to back up a bit?
It looks looks like it is seeping from around where the oil pan attaches 
to the block and where the small addition to the attaches to the oil pan 
on the exhaust side.
Do the front crank seals go away on their own very often?

Ideas, Wisdom or BTDT's  appreciated.

Thanks
Chuck
91 200tq 20v Avant