Chevrolet Repair: 1999 venture van, compression check, venture van

Question
Hi,
I hope you can help.
The other day the wife was driving home and she heard a thump and then the oil light, Bat.light and the van shut off. Had it towed home and I started to check it out.I am not a total novice to this but I need help.
The van will start, valve train is noisy, Sounds as if it is popping out the air intake.
If the oil filler is removed does not look as if any oil is flowing also does not look as if #6 intake valve is moving and Oil light is on.
Did a compression check on the front bank and # 2 IS 200, #4 is 195,#6 is 70. Cannot get my gauge into the rear bank,need a longer hose.
I am thinking either the oil pump quit and a lifter collapsed or something give way like valve spring,or pushrod and possibly lifter popped out resulting in no oil pressure.can you help me out as to what I should do next Thanks  

Answer
with what your describing and the compression check you performed, its not good thats for sure. sounds like you lost compression in #6, bent valve or broken valve spring could cause this. either way I would recommend bringing this to a qualified mechanic that you trust for further diagnosis