Cigg,s ,I don,t think you have grasped the difference between...

Cigg,s ,I don,t think you have grasped the difference between porosity and permeability.Both formations you mention could have all the porosity you could wish for but with out permeability nothing is going to flow any-where.Next - why do you think the formation fluid is going to flow from the upper formation to the lower formation? After you perforate a well , you then reduce the hydrostatic pressure in the well and allow the fluid in the rock adjacent to the perforations flow into the well, if you have two defined formations you would perforate both. I am not suggesting that this well has low permeability , only that to suggest that porosity values are a guarantee of good flow rates is nonsense. The diagrams you posted show rock with high porosity and good permeability.Imagine the rock particles all touching each other at some point, you still have spaces between the particles - thats your porosity,but each oil filled gap is isolated from the next by the touching rock particles , now you have no permeability and no oil well.
As for not being sure and having to "google" not necessary , I drill oil wells for a living.

have a nice day.