Why do I start losing oil pressure after running the car for a few minutes.

I have a 1997 camaro v6 3.8L with a 5speed trans. When I start the car the
oil pressure gauge shows pressure set at 60 ( indicator in the middle ) As
the car idles, I notice indicator starts dropping until it drops in the red. I turn off the car when I start hearing tapping noise from engine to
avoid further damage. What do you think might be causing this problem and
what would you recommend. Thanks
Etorres97