When oil companies have a discovery, sometimes after they have done the evaluation of the original drilled hole, they decide to sidetrack the well to reach further in another direction. This plan to sidetrack needs to be approved in advance with government regulators.  Often times the company will drill the sweet spot e.g., of  an expected oil reservoir and then sidetrack to look for an oil water contact and/or a gas oil contact and/or to find the exact boundary location of a reservoir.  This data is used to prove up the "size of the prize"  i.e., the volume of HCs in place.  They then update their static and dynamic reservoir models to prepare field development plans and conduct economic analyses.

The 60 day estimate for Wahoo sounds very short, so that number likely has no sidetrack provision as part of the exploration plan.  But perhaps after finding pay, they decided they needed to sidetrack one or more times to get more reservoir information.  This might be the case especially if the discovery is oil.  E.g., the gov't might not like them flaring a lot of oil at $100+ a bbl.

So this would be a very wonderful surprise to hear of a large oil discovery which included one or more sidetracks proving up a millions of  barrels.

The shallow well depth, however, makes it difficult to look much further away  from the original hole.

I think when we are drilling into a very thick pay zone that might be filled with gas we have to prepare for the zone to be over pressured. In order to do that we have to set and cement casing as close as possible to the top of the pay zone. That would mean all of the side track hole would be in the pay zone itself. Probably not worthwhile. Of course they could mill a hole in the casing and side track like we did at Antelope-2 for the horizontal hole but I do not think they will do that. In these thick limestone reservoirs we will probably find the gas/water contact in the vertical hole without drilling a sidetrack. In other words the thickness of the reservoir rock will be thicker than the gas zone, at least it is at Antelope. At Black Bass-1 the limestone was not so thick but I think they are expecting it to be thicker at Wahoo, possibly because they think there is a reef buildup that was not present at Black Bass. If the pay zone turns out to be thinner than the gas column then we will have to drill other wells down dip to look for the gas/water contact. That would mean the entire pay zone is full of gas to the bottom of the zone. Not a bad problem to have especially if it is a thick pay zone and still no gas/water contact.

Also another reason that I think there will be no sidetrack is that I think they will set and cement a liner across the pay zone and do some drill stem tests inside of casing. If they do that all of the hole will have casing so they can’t sidetrack unless they mill a hole in the casing somewhere above the pay zone of the original well. Just my opinion for what it is worth.

And if it is oil instead of gas? Well that is another story for another day.

'Getitrt2' pid='44986' dateline='<a href="tel:1402669 Wrote:Pet, I would consider that a very restrained and diplomatic technical response, and would say your "opinion" is "worth" a hell of a lot. Maybe I should just keep my mouth shut, but after all these frustrating years, I guess I find it too hard. Imho, the suggestion starting this thread that in this situation this Company and management would drill and test this well confirming a dry hole or discovery of any size, and then keep it secret while drilling a "sidetrack", essentially another well, to get more information about the formation and discovery, is LUDICROUS!!! And what's this about "flaring" a lot of OIL, like flaring gas; is that real?!

Pet makes some good points above.  It sounds like Get misunderstood.  You don't test a dry hole.  It is a standard operation to drill a sweet spot, original hole to make the discovery.  If there are no HCs in this hole then you are likely done.  Logs pretty much confirm this case.  But if you hit a convincing pay zone, then you may sidetrack for lots of reasons to confirm your models and reduce uncertainty.  That's sort of what's going on as E/A.  But because it is so large in areal extent, they have to drill new wells much further away to get the data.

i recall looking at slides of Triceratops and was surprised to see that the target deposition is a steeply dipping bed.   That means if you drill in one location vertically straight down you will not see the OWC if you are on the high end of the structure (which is typical in exploration).  You would have to sidetrack and drill a deviated well downdip to try and find the OWC.  But with a huge structure you probably can't reach it.  You might have to move the rig miles away (you hope!!).  So with a steeply dipping structure with full pressure communication, Pet is right, you could have abnormally high pressures when you penetrate the structure at the most updip location.  But if this structure is relatively flat over its whole extent, then the pressures won't be excessive and yes you might penetrate a GWC if you drill straight down and thru the structure.  The seismic should reveal the dip.  I have not hunted thru the presentations other than Tricertops so, not sure about what's here at wahoo.

Of course the bad reasons for sidetracking are due to screwing up the primary hole to where you can no longer progress.  It's cheaper than starting with a brand new well location.

Hope that clarifies.