Why is my Vauxhall Zafira using so much oil?

We have a Vauxhall Zafira 2.0 DTI Life (2004) however recently when I was under the vehicle I noticed a lot of black sludge on the under-engine cover. Upon closer inspection from the engine bay, there is quite a lot of this sludge around the front of the engine (just behind the radiator). I topped the oil up to 4.5 out of 5 on the dipstick, completed a journey of 150 miles and then after leaving the car for 30 minutes decided to check the oil. The oil had gone from 4.5 out of 5 to 2 out of 5 on the reading. Either, this car is losing oil or it's burning it at an alarming rate. What do you think is causing this?
It appears to either be using oil or blowing oil out of a breather possibly due to a blockage.
Answered by Honest John on

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