The Permian Midland USGS Assessment -- An Oil & Gas Journal Update -- June 23, 2018

Updates

June 24, 2018: the graphic below is already out of date. Look at the "Western Gulf Province": 1.73 billion bbls. The USGS just released the 2018 assessment of the Eagle Ford, which came in at 8.5 billion bbls of crude oil. For an overview of the USGS Western Gulf Province, see this site (conventional gas). It's possible the updated graphic will include two areas: the Western Gulf Province (conventional) and the Eagle Ford (unconventional).

Original Post

Wow, I'm in a good mood. So much great stuff being reported. I can't keep up but that's good news.

This article needs to be archived. I finally understand the Permian a bit better. Mike Filloon had the Permian figured out many years ago, but, for me, it never sunk in. Re-reading Filloon's articles on the Permian and now this article in the OGJ, I finally have a better understanding of the Permian. The OGJ article was published June 4, 2018, but other sites suggest the USGS Permian assessment was done during 2016, and first reported in 2017, with some additional articles on the same subject after. For now, I guess we will refer to this as the USGS Permian Assessment, 2017.

Unfortunately, it may be behind a paywall. Here are the high points.

The Permian, there are three sub-basins:

• the Midland, to the east (this is the area assessed in this article; two plays in this basin assessed: the Wolfcamp and the Spraberry)
• the Central Basin Platorm
• the Delaware

The formations, many, but these are the most important right now:

• Pennsylvanian-Permian Wolfcamp shale: underlies both the Midland and the Delaware, and extends across the Central (in other words, underlies the entire Permian Basin)
• Bone Spring formation: the lateral and time-equivalent of the Spraberry in the Delaware
• Spraberry: see above

Intro: the USGS recently assessed the Wolfcamp shale in the Midland basin portion of the Permian basin for continuous (unconventional) oil and gas resources, and completed a reassessment of the Spraberry formation for both continuous and conventional oil and gas. Combined, the assessments of the Spraberry formation and the underlying Wolfcamp shale in Midland basin comprise the largest domestic continuous oil assessment in the contiguous US (including Alaska).

Great graphic with all (?) US producing areas assessed by USGS and undiscovered, technically recoverable resources:

• Permian Basin: 24.19 (this is a little confusing, because the Midland was assessed at 24.2 and yet the Midland is only one of the three basins in the Permian -- the Midland, the Delaware, and the Central basin -- see very last line in this post -- that explains it)
• Williston Basin: 7.62
• Western Gulf: 1.73
• Appalachian basin: 1.4
• Alaska North Slope: 0.94
• North Central Montana: 0.64
• Paradox basin: 0.47
• Cherokee platform (eastern OK): 0.46
• Powder River basin: 0.42
• Anadarko basin: 0.39 
• Bend Arch Fort Worth basin: 0.17
• Southwestern Wyoming: 0.10
• Denver basin: 0.04
• Uinta-Piceance basin: 0.03
• Montana thrust belt (western MT along Idaho border): 0.03
• San Joaquin basin: 0.02
• Los Angeles basin: 0.01
• Bighorn basin: 0.01 
• Mean total: 39 BBO (note: mean)
• most areas were assessed between 2001 - 2018

Here's the graphic:

Spraberry formation:

• upper, middle, and lower
• operators mostly interested in middle and lower Spraberry
• informally, the lower Spraberry is further sub-divided into the lower Spraberry shale and the lower Spraberry (similar to the Bakken; more on this later)
• the industry also refers to a "Jo-Mill" play in the upper section of the lower Spraberry, a silt-rich interval
• recently assessed, 2017

Wolfcamp shale: divided into a total of six AUs

• Midland Basin Wolfcamp A Continuous Oil AU
• Midland Basin Wolfcamp B Upper Continuous Oil AU
• Midland Basin Wolfcamp B Lower Continuous Oil AU
• Midland Basin Wolfcamp C Continuous Oil AU
• Midland Basin Wolfcamp D Continuous Oil AU
• Midland Basin Northern Wolfcamp Continuous Oil AU
• assessment based on limited well data with 0.10 - 0.14 MMBO, with the highest EURS estimated within the Wolfcamp A and B horizons

Total oil resource, Spraberry:

• 4.2 billion bbls of oil
• 3.1 tcf of gas
• majority of this assessment is attributed to the two Spraberry continuous AUs (the Middle and the Lower)
• a mean of 5 million bbls was assessed for the Northern Spraberry Conventional AU
• in comparison, the mean total assessed in 2007 for continuous and conventional resources of the Spraberry formation (based on vertical wells) was 530 million bbls of oil 

Total oil resource, Wolfcamp:

• assessed for the first time in 2016
• 20 billion bbls of oil
• 16 tcf of gas within six continuous AUs

Total oil resource, Wolfcamp + Spraberry:

• 24.2 billion bbls in the Midland Basin

The report references the 2013 Bakken assessment:

• 7.4 billion bbls (Bakken + Three Forks)
• at the time, this was the largest domestic oil assessment conducted by the USGS
• the addition of the Heath (Tyler) formation, assessed in 2016, raises the total assessed continuous oil resources in Williston basin to 7.6 billion bbls of oils
• the recent assessments of the Spraberry and Woflcamp formations in the Midland basin nearly tripled the Bakken, Three Forks, and Heath formations
• the Bakken is currently being re-assessed by the USGS; at the time of the last USGS assessment of the Bakken, CLR's EUR type curves were 400 - 500 million bbls; CLR's EUR type curves now exceed 1 million bbls;

Conclusions:

• the Midland basin contains the largest estimated continuous oil resource by the USGS.
• additional assessments are underway in neighboring Delaware basin that will ultimately alter the total mean resources projected by the USS for the the greater Permian basin