Utica Well Production Variability - 100-500% from the same Pads

What strikes me from looking at the Q4 2013 production report is the extreme variability in production, even from wells on the same pad just tens of meters apart at the surface, though granted they are a mile or two apart in production zones. Take some of the Gulfport Wells for example. 

Related story here with links to maps. Wells from the same pad varied by 100% to 500% in BOPD

This tells me that we still don't know a lot about how to best produce the formation and that we are still in a huge learning phase. Operators must be scratching their heads as to why production forecasts don't pan out. With such extreme variability I doubt that anyone knows even half of the whole story. And I am sure that many Geologists struggle to explain production results to their bosses after the fact when all things were supposed to have been equal.

Gulfport Q4 2013 results from pad wells:

  • Boy Scout wells: Production varied from 93 to 326 barrels of oil/day
  • Wagner wells: Production varied from 19 to 108 barrels of oil/day
  • Stout wells: Production varied from 51 to 101 barrels of oil/day
  • Clay wells: Production varied from 78 to 203 barrels of oil/day

If we see less variability in Q1 2014 data I will be encouraged, though I would bet that a 100% difference in production from the same pad will still be common, which is telling. 

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Permalink Reply by Greg B on May 10, 2014 at 2:12pm

So "they don't know until they drill" really can lead to variable results alone. And they may not have kept the horizontal well path in as good a zone as an adjacent well. Seems like they ought to be gathering more data (microseismic, surface seismic, adjacent well logs, etc) to get it right. And even after drilling they might not frac at the best locations/stages (variable stress fields and clay composition for example). Then there is frac proppant and fluids, normal fractures, rest periods, and on and on, So many variables to get right and optimize. Sounding more and more like rocket science. Slow and methodical should payoff. Gulfport Energy is doing it right, slooooow down as opposed to frac and pray.

Permalink Reply by Kangoo on May 10, 2014 at 9:18pm

Interesting observation Greg.

However in general the Utica/Point Pleasant is a lot more 'repeatable' as some other shale plays.

Often the explanation for the differences will be for example the date when each of them were brought on (due to decline of production) or number of stages/lateral length or frac design or any operational issues during fracs.

The Wagner well with the 19 bbl/day average for example was completed in May 2012  whereas the other two wells were only completed in August 2013. (based on the data in the ODNR well data base)

So in this case the first wells is far further down the decline curve and producing less.

The Clay wells on the other hand appear to have different frac designs (again based on the stimreport on the ODNR website). So they might have learned something from this well.

Also with wells where the majority of production is gas, I'd mostly look at gas rates, since on a multi well pad depending on the facilities set up it is not difficult to incorrectly allocate oil production to a specific well (gas production usually is measured more accurately).

All in all I think the numbers are a lot clearer to the operator and not too confusing. It's just much more difficult to assess with the data available to the public.

 

 

Permalink Reply by Jim Litwinowicz on May 10, 2014 at 10:23pm

Some good points Kangoo:  I was also wondering about completion dates.  A well drilled third or fourth on a pad will have much better design.  It is so early in this thing that they are learning more and getting better with every well. Not saying this is all the cause.  May be possible for a later well to produce poorly if the new recipe doesn't work.  

And I talked to a top oilman a few years ago and he said that shales can change quickly in just a mile or two.  Meaning a well running a mile or more in one direction could have different numbers than one running the opposite direction.

Permalink Reply by Greg B on May 10, 2014 at 11:28pm

Thanks for the comments guys, I was guessing that pad drilling was done for efficiency and that they wells were put into production about the same time, the case for some, but not all. Decline rates alone can explain production drops for wells put into production much earlier. In general, do wells from the same pad come online about the same time?

Permalink Reply by Philip Thackray on May 11, 2014 at 8:35am

Greg B asked “In general, do wells from the same pad come online about the same time?”

Speaking for the Rex and XTO well sites in Western PA that I have followed – the answer is No.  Nor does the permit date predict which wells will come online at the same time.  Perhaps the best measure of coincident online times (using a normally available metric) would be the spud dates.  Maybe in Ohio they tend to “drill out” the pad but back in W. PA its musical pads.  Drill a few wells, frack them, put them on line, leave for a year or two, return and repeat.  This is further supported by the trend to multiple units from one or two well pads.  The nearby Shipley South unit does NOT contain the well pad from which the wells are drilled.  It looks to me like this well pad will support at least three units.

Regards,

Phil

Permalink Reply by pg guy on May 12, 2014 at 11:48am

An important variable in oil production consistency (or lack therof) is the status of gas sales from the well.  Is the gas production normalized, i.e., is there consistent processing, compression, line pressure, etc, allowing gas flow from the well to be consistent?  Or is gas sometimes partially or completely shut-in for production facilities maintenance, repair, or upgrade activities, or curtailed pipeline take-away capacity?

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