USGS 2021 Survey, Bakken And Three Forks: Bakken: Still Has 4.3 Billion Bbls Of Undiscovered Oil -- This Is In Addition To The 8 Billion Already Proven Or Produced -- Williston Herald -- December 21, 2021

From a reader, thank you, link here:

In 2013, the Bakken and Three forks formations in the Williston Basin had 7.4 billion barrels of undiscovered but technically recoverable oil and 6.7 trillion cubic feet of undiscovered natural gas, according to a United States Geological Services survey.

Since 2013, more than 11,000 wells have been drilled in the Bakken and Three Forks formations. Produced resources, of course, no longer count as undiscovered. And the same goes for proven reserves.

Those factors have dropped the amount of undiscovered oil in the new undiscovered resources report substantially, to 4.3 billion barrels. Undiscovered gas, meanwhile, dropped to 4.9 trillion cubic feet.

The Geologic Survey, 2021, is linked here. 

Lynn Helms:

• at one million bopd, existing well inventory will produce another four billion bbls crude oil;
• another 4.3 billion of undiscovered or undrilled
  

This brings us back to discussions of OOIP. I'm not going to re-open that but I'm pretty confident I have a pretty good "feeling" for the Bakken.

Look how far we've come. 

These charts only go back to 2012, five years into the Bakken revolution. 

But even in 2012, with 200 active rigs, the Bakken was producing only 600,000 bopd. Earlier, the numbers were even higher (rig count) / lower (crude oil production):

Link here.  

2012: 200 rigs / 600K bopd production.

2019, pre-Covid, when things were "good": 50 rigs / 1.25 million bopd /

2021, Covid transitioning from a less-infectious Covid variant to a more-infectious variant; 25 rigs / 1.2 million bopd .

Completed wells per annum: perhaps the most amazing data point was the number of completions vs production. At one time, upwards of 3,200 wells were being completed in one year, and less than 750,000 bopd were being reported. This year, 1.1 million bopd and "we'll" be lucky to complete 350 wells this year (2021).

I've long lost the bubble but I believe that when the blog / Bakken were reaching their stride, the dots suggested that operators would be drilling new wells through 2050 and those wells, lasting thirty years, meant the Bakken could be active through most of the 21st century, if not the entire 21st century. Vertical wells drilled in the 1950s are still producing. That was seventy years ago. 

Eight billion bbls remain / 1 million bopd = 8,000 days = 22 years.