Which mechanisms of water intrusion into oil wells are relatively easily controlled (select four only):
__ Watered-out layer without crossflow.
__ Fractures between injector and producer.
__ Moving oil/water contact.
__ Coning.
__ Cusping.
__ Casing leaks.
__ Edge water from poor areal sweeps.
__ Gravity segregated layer in a thick reservoir layer with high-vertical permeability.
__ Channel flow behind the casing from primary cementing that does not isolate water-bearing zones from the pay zone.
__ Fractures or faults from behind the water zone.
A fairly straighforward problem; you will either know it or you won't (depending on how well read or experienced one is). I'll update this problem answer later, to let the problem "sink in" and become ingrained in your mind. Remember, there are a dozen ways this probllem could be asked, so one must have a true understanding if it to be safe!
Watered out layer (squeeze cement)
ReplyDeleteMoving contact (change perfs and abandon toe)
Casing leak (use liner)
Gravity segregated = moving contact
One of the challenges for the PE exam is knowing the HS very well, because that's the SPE source that will be usually used, along with the SPE TS. Take your time and read HS P381 carefully and that will give you the "thinking" the test will likely use. Remember, it pretty much has to be a direct quote or something very similar.
DeleteCan you explain in more detail the difference between the gravity segregated case and the primary cement failure? I would have thought that the cement failure would be harder since a failed cement remediation would lead to a permanent dump flood on the backside.
ReplyDeleteNever try to overthink this exam. Think like the test-writers; they know there is a lot of opinions are variations in how people think about these things, and will therefore stick very closely to an SPE source they can directly quote. So just read the HS page closely and don't go beyond it, because this exam is hard enough as is :-)
DeleteThank you! Can you remind me again what documents HS/TS are (is there an in-house version of the SLB oilfield glossary with the shorthand notation used on your site)?
ReplyDeleteHS & TS are just the SPE Handbook Series and SPE Textbook Series. Just to be clear, nobody knows what will be on the exam, I'm just assuming the exam will be fair and follow the SPE references, and it always has done this in the past to my knowledge. And the TS is very advanced, so that reference will be the most basic parts of it so you should be able to just review the most basic stuff in the common volumes like TS 1, 2, 3, 8, 12. My Problem sets cover most of the material you should get familiar with in these texts.
DeleteThank you!
Delete