'Kaliboo' pid='67193' datel Wrote:
'petrengr1' pid='67164' dateline='<a href="tel:1457037 Wrote:
'sageo' pid='67158' dateline='<a href="tel:1457018 Wrote:Pet - As aways,thanks very much for the March 1 post above. (great education you are providing us ! ) I thought we should be at least 100 ft into the reservoir antd it now looks like about 203 ft . ( close to 40 ft of dolomite as of today's report) .....hope at least one of those cores was in a fractured limestone area with good porosity. Looking forward to when you post your next "educating lesson".
Antelope-5- There is a bit of a discrepancy between the data reported today as compared to the data reported on the first test http://tinyurl.com/q2lzmbq page 17. On the first test they say they produced 60 MMCFD through two 48/64” chokes. Now on this latest test they say they produced 57 MMCFD through a (one?) 48/64” choke. One or the other is incorrect.The good news is, of course, that the new data has confirmed the connectivity between Antelope-5 and Antelope-1.They are still evaluating the pressure buildup data to “quantify nearby reservoir properties”. I do not know what this means unless they are trying to prove the distance to the nearest fault. I assume that would be the western fault. As I have stated before I do not think they can learn much from a near instantaneous 2 psi pressure buildup but I wish them luck. I do not know what more they can learn about the permeability since we already know it is unbelievably high as proven by the 2 psi drawdown for 60 MMCFD.We await the additional data of the reservoir pressure loss for the amount of gas produced which is what they would use to try to estimate the gas in place in the reservoir.Antelope-6I will try to tell you what we know and what we don’t know. IOC has been using sub sea depths in all of their previous reports but today they switched to drill depth, just to keep us guessing.They have previously reported that we topped the reservoir at -2,076 meters sub sea or about 76 meters lower than they had it mapped. The top of the pay would be at 2,262 meters drill depth. Today’s report says they cut four cores across the interval from 2,268 to 2,330 meters drill depth. They do not indicate if all of the interval was cored or part of it was drilled without coring but the depth of the hole is currently 2,330 meters drill depth (-2,144 meters sub sea). They say a 9 5/8” liner was set at the top of the zone (2,262 meters drill depth). So we have open hole from 2,262 meters drill depth to 2,330 meters drill depth or 68 meters (223 feet) . They tell us “Preliminary interpretation shows approximately 12 meters of dolomite is present in the drilled section.” What we do not know is where the 12 meters of dolomite is in the 68 meters of drilled hole. Is it at the top of the zone, the middle of the zone or the bottom of the zone? It makes a big difference. The best possible scenario would be that they have high porosity limestone from 2,262 meters to 2,250 meters and then 12 meters of dolomite at the bottom of the hole. That would mean they were still drilling in dolomite when they decided to log and test. At Antelope-3 we had high porosity limestone above the dolomite section and the dolomite section was in about four different segments with limestone between the sections of dolomite. See the logs at http://tinyurl.com/l2j4c2w page 17. So no matter where the dolomite section is in the drilled interval it is still possible that we will have more dolomite when they drill the rest of the hole. The bottom of the hole is presently at 2,230 meters drill depth or -2,144 meters sub sea. We know the gas/water contact is somewhere between -2,214 and -2,228 meters sub sea. IOC has been using -2,214 but Hession has said data from Antelope-4 and Antelope-5 indicate the gas/water contact may be lower than they had been using. The -2,228 meters sub sea number was from the GLJ report and I think it is the most likely depth for the gas/water contact. So using -2,228 meters sub sea we have another 84 meters (276 feet) to drill before reaching the gas/water contact. I think some of that formation yet to be drilled could be dolomite.Now let’s look at the test data. On the surface it does not look too great, 13 MMCFD on a 40/64” choke. What we do not know here is whether or not they have a bottom hole choke in the DST tools, what the tubing (drill pipe) size is and whether or not we have formation damage caused by drilling fluids. If the dolomite is as good as previous wells 12 meters (39 feet) of dolomite should produce more that 13 MMCFD on a 40/64” choke. They did not give us the flowing tubing pressure at the surface but I would guess it to be about 1,200 psi. So we have a lot of pressure loss for some reason...bottom hole choke, small tubulars and/or formation damage. As you know the reservoir pressure is about 3,500 psi. If we have formation damage they will determine that by analyzing the bottom hole pressure build up data after they pull the DST tools and gauge. Formation damage in a high porosity limestone or dolomite can be corrected with hydrochloric acid.I am looking forward to hearing about the final log and flow test information, if they do further testing.Nice job Pet, as usual, on all your diligence and thorough analysis. Here's some thoughts. All comments welcome.
Well 5: The release said this: "Preliminary analysis has confirmed the excellent reservoir quality and connectivity seen in the initial Antelope-5 production test conducted in mid-2015. The forward plan is to undertake further analysis to quantify nearby reservoir properties."
it's not surprising, but is disappointing that the "forward plan" is so vague. I presume the meter is running on a lot of men and equipment waiting on further orders. After drilling, logging, sampling and production testing, what else do they need to quantify nearby reservoir properties? I'm guessing they may obtain rotary sidewalls from some key points of interest?? If so, then they may be already done. Can't recall their statements but what else would they do on this well unless they screwed up something (e.g., corrupted data) and are considering what has to be repeated??? I have not heard of any plans to sidetrack, but that might be a remote possibility to obtain more rock samples further from the current location to better characterize the properties.
Well 6: I suspect IOC is merely cutting and pasting TOTs report which relies on measured depth as the convention. IOC doesn't want to create compound errors in TOT's report by translating it. This keeps all accountability for erroneous statements on TOTs back. My guess. If the dolomite was at the bottom of the hole, then I think they would have continued drilling to have a larger section before testing. I suspect that they likely drilled a long section of nonproductive rock below this dolomite section and concluded they may be out of the reservoir. I.e., there may be nothing below. The flow test perhaps was conducted to see if this well was in a small, isolated reservoir OR whether this was connected to the main reservoir. If an isolated box, then further drilling would be less likely to bear fruit. But of course if connected, then they probably should continue to see if more reservoir rock is deeper. The long buildup after the flow test is likely indicative of very tight rock. If they are in a small separate reservoir, then the buildup would confirm that sooner. The flow rate was certainly low.
Kaliboo