sudden oil leak

recently drove 600 miles and only used 1/2 qt. On arriving back home after another 600 miles, oil light started flashing. It was 3 quarts low. Have noticed small oil trail into garage and small puddle, but only leaks for a few minutes after parking. Obviously only leaks when engine is running. Seems to be coming from near crankshaft cover, definitely above the oil pan gasket. Not coming from filter though. Any ideas?

Thanks!

crankshaft cover? you mean oil pan?

clean the engine then inspect for leaks
my guess valve cover gasket and/or oil pan gasket

It's somewhere behind the timing belt covers, etc on the front of the engine. oil is hitting the bottom of the alternator belt.