RE:What isHi dragonfly,
I refrained from reacting to your Extrapolation post but now that you're openly asking the question, I will answer. There is no short, straightforward answer and this is the reason why I am cautious when I state my assumptions and we should not be thinking in terms of x meters/day because this is not how it works. Drilling is not linear.
Apologies in advance for the technical prattle but if it helps to clarify..
Drilling is not a linear process, which is the main reason why, especially right now, we shouldn't extrapolate. On an exploration well like that, you spend typically "only" 35-60% of your time "drilling" i.e. making hole (I put a large bracket to cover most cases). Therefore, to begin with, it is unhealthy to imagine "5 days ago they were at x meters, they must be drilling at 30m/day so now we must be at x+150m".
We (all of us, including myself) do not know what the heck they have been doing during the subject 5 days of my example above.
They may have been running casing/liner, they mave have then cemented it, waited on cement, maybe they had a BOP test (every 21 days but you will go for it even before 21 days if you know you'll drill a section that will take time because you don't wanna be out of the testing period in the middle of a section). They may have been painting the derrick pink, for all intents and purposes, we do not know so we should not extrapolate.
Now, you may want to look up for one of my previous posts where I stated there was an anomaly in the time/depth curve moving 74% to 78% in about a week. The reason I stated that was not based on anything linear, it was mainly because based on these depths (we're below the interm. casing shoe but demonstrably above the Campanian, even a bit on the high end) they should have been making hole, going deeper, because this is not a place where they would set the contingency liner (the 11-3/4"). I can explain why but it is already a lot of text on obscure subjects, so just take it as it is, the 74% to 78% interval is not where they will set the 11-3/4" or spend extra time, unless needed.
Based on that, for me they were "navigating gently through" some difficult layers where they were facing wellbore breathing, hole stability variations, inefficiencies due to drillstring mechanics on formation change, maybe some stingers/cherts, you name it, I have no crystal ball. But if I had to bet, as already stated, I would bet on wellbore breathing and stability, because the guys on B58 had them too, in exactly these layers.
Then, to come to a sort of answer regarding short term future, these layers will need to be cased with an 11-3/4", because it is standard practice to do it, given that it would bear an element of risk (not for the well as such, mostly NPT i.e. lost time) to go into the reservoir while having these problematic zones open behind you.
This is the reason for my very short post of tonight, urging for patience. Of course I may be wrong in my assumptions but based on my professional experience, seeing these bits and pieces of information, I am nearly sure that they will need to run this 11-3/4" and if such a bet existed, I would bet on it.
I have no data to guess when they will run it, if it has already been run or is being run as I write. Gut feeling, just gut feeling, tells me that we may be running it now or in the coming days. It will take around 3 days to run this 11-3/4", cement it and wait on cement. Then they will probably perform the next BOP test, put another day (this is normally shorter but put down a day, for patience-training). Then they will drill that shoe, perform a leak-off test (nothing important for us here), i.e. another day and only then drill through the Campanian.
Putting it altogether, you need conservatively around 5-7 days from the moment you started running that liner until you see the Campanian, hence my short post of the evening about "patience", hinting that this whole week can pass by without anything else than noise.
And this is the reason why I said "I really hope I am wrong" because if I'm wrong and we're not running that liner, then, yes, we may have already been through the Campanian or see it anytime in the coming hours/days. But better be armed with a touch more patience, folks, because I am nearly sure we will run (have been running, less likely "have already run") that 11-3/4".
And, just rest assured, painstaking and time-consuming as it is, this part is not an obstacle on the success of the well. The guys on B58 went through there, they are real topguns, the CGX guys will also go through there because they're of the same caliber, no doubt.
Patience folks, patience.
GLTA,