While the subject acres are not very far from production, they are not very close to any good production either. The production in the area looks fair for the short lateral Bakken wells I looked at fair because they are cheap less than 1 mile laterals. There was only 1 long lateral [1 mile long] in the group I looked at and it didn't look impressive.
Looked at two ways, the subject acres in my opinion are not proven and even if they were the equal of the surrounding acres could take a decade to pay you $425 an acre leased at 1/8 or even 1/6. I wish I knew what he based the valuation on. If I had to give the acres an absolute value, I would say they were worth less than $425 an acre, alot less. Speculative value could be more than $425 an acre but speculation is gambling and the nearest well, the one with the 1 mile lateral, operated by Continental Resources, Bicentennial Federal 10-34H has produced 16,310 bbl oil in 25 months. I don't see anyone rushing to try to duplicate that feat. When I set the map filter to 30 miles, there is not a single rig symbol. If someone were to want to buy the subject acres it would be, in my opinion to add them to their portfolio to see if they would appreciate or possibly there would be some exploration decades in the future.
If I had to guess, whoever did the valuation probably extrapolated what the lease bonus would have been at 1/6 royalty and quadrupled it. If that was what they did I think it would have been wrong. The closest production to your acres if anything, would lead one to believe that the acres are unproven and risky to explore. I don't think they have as much value as they did in 2010, possibly no more value than the 2010 lease bonus.
As I said before, you couldn't rule out that someone would offer you $425 for the acres, people do strange things sometimes. If someone bought the acres from your for $425, it's even possible that they could find someone who would pay $625 for them, it's called the greater fool theory, but I wouldn't hold my breath.
Another thing, the lease. If the lease is still in effect, which I assume it is if executed in 2010 and it had a primary term of 5 years, if this lease is at 1/8 royalty, it damages the value of the acres burdened with a poor lease. People buy minerals because they hope to make money. Who in their right mind would pay $10,000 for acres that might pay them back $10,000 in 10 years, if the wells, both of the needed wells were drilled today? I don't think you would have much luck finding a greater fool until that lease expires. God only knows what else is in that lease, post production costs? transportation? You might ask whoever gave the valuation if they based it on value right this instant, or on the best of all possible worlds.
That said, it's easy for me to sit here and pick their work apart, no professional would appreciate that. It might not do any good to bring up what I have just told you. In my opinion I just spent more time working on the valuation than your appraiser did. While it may not please them to hear the question, I would ask them how they arrived at the value they did. I frequently end these things with I hope this helps, and I mean it! Somehow, I don't really think it will in this case, but you asked and it was an interesting exercise.