640-Acre Spacing vs 1280-Acre Spacing in the Bakken

Elsewhere there is a nice discussion of EOG's infill plan in the Parshall oil field. One individual suggested EOG needs to do something to "arrest" the decline rate. Yes.

This gives me an opportunity to note the waste in 640-acre spacing.

Study the Parshall field at the NDIC GIS map server. 

Take any two horizontals in the Parshall field that are in "kitty-corner" sections, in which the northwestern well is sited in the far northwest corner of the section, and then proceeds at a 45-degree angle to the southeast, ending short of the section line. Then go to the far southeastern section of the "kitty-corner" section, to note the well sited in the far southeast corner of the section, and the horizontal ending short of section line.

Now, using the "distance" application, note that the horizontals are almost exactly one mile long.

Now, using the "distance" application, note that the ends of the horizontals, or the "toes" as they are referred to, are almost exactly 0.6 miles from each other.

Also note that the wells themselves are offset from the section line, resulting in another 250 to 500 feet of lost horizontal potential.

Larger spacing units, even 1280-acre spacing, eliminates much of this waste. 2580-acre spacing will eliminate even more and at the end of the day (twenty years from now), it will make a huge difference. It all adds up -- the waste. Compare the amount of "waste" in the Parshall field with its 640-acre spacing and the Sanish field with its 1280-acre spacing.

This is not trivial. If one searches "decimal" on the Bakken Shale Discussion Group, one will find the following comments not atypical:

I believe my decimal interest is 0.00551020 so we are really curious what we could expect from this well in the future. 

Mineral owners concerned about the decimal figure out to the 7th or 8th place, should certainly be concerned about "their" horizontal well missing 40 to 50% of its potential. If these were straws going into pools of liquid, it would not matter, but Bakken wells are going into sand that requires fracking for oil to be released.

At least that's how some see it. This is not an original thought with me. Others have expressed the same thing. I polled readers of MDW on this issue some time ago and the results were interesting.