Bakken EOR Test Using Injected Hydrocarbon; Ross Oil Field; Hess -- March 7, 2017

Bottom line:

• Hess to test enhanced oil recovery using injected hydrocarbon gas. Two vertical wells in Ross oil field have been drilled for this test
• apparently EOG has been doing similar testing in the Eagle Ford for the past two or three years (see end of post)

Graphic:

The wells:

• 32937, IA/drl, Hess, RS-Nelson Farms-156-92-24V-1, Ross, a Birdbear well, no production data, PGI for the Bakken well; noted to be IA (posted January 24, 2018)
• 32938, SI/NC, RE-Nelson Farms-156-92-24V-2, Ross, drilled to Birdbear, below the Three Forks; still SI/NC, posted January 24, 2018;

FracFocus: as of March 7, 2017 -- no data at FracFocus regarding these two wells.

*******************************

32937 (V1)

32937 (V1), API: 33-061-03974; geologic summary --

• spud: September 9, 2016
• cease drilling: September 14, 2016
• TD: 9,974.90' TVD
• drilled as part of a projected Hess's Enhanced Oil Recovery (EOR) group, RS-Nelson Farms 156-92-24V-1... vertical hole targeting the Middle Bakken and Three Forks Formation where a 210' core was taken
• the 210-foot core was taken from 9,587 feet MD, an estimated 10 feet below the False Bakken, to 9,797 feet MD in Three Forks Formation
• The False Bakken, the upper Bakken shale, the middle Bakken, the lower Bakken shale, and all four benches of the Three Forks are described in the file report, as well as the Birdbear

*******************************

32938 (V2)

32938 (V2), API: 33-061-03975; geologic summary --

"As part of a project by Hess's Enhanced Oil Recovery (EOR) group, RS-Nelson Farms-156-92-24V-2 was drilled as a vertical hole to monitor the RS-Nelson Farms-156-92-24V-1. The surface location ..... located in Mountrail County in the Ross Field.

"RS-Nelson Farms-156-92-24V-2 spud on September 21, 2016, and reached a total measured depth of 9,983' on September 24, 2016, at 5:00 a.m. CDT. This (#32938) was the second of two verticals drilled on this well pad.

"Thirty foot samples were caught from 7,470 feet through the end of the vertical section at 9,983 feet in the Birdbear Formation."

The False Bakken, the upper Bakken shale, the middle Bakken, the lower Bakken shale, and all four benches of the Three Forks are described in the file report, as well as the Birdbear. 

Disclaimer: in a long note like this there will be factual and typographical errors. I am doing this to help me better understand what is going on in the Bakken. Do not quote me on any of this. If this is important to you, go to the source.

*****************************

The Proposed Hydrocarbon Injection Test

32937, brief description of proposed injection program, pages 27 - 28 of the 126-page file report. Data points:

• "The objective of the proposed enhanced oil recovery (EOR) test is to demonstrate enhanced oil recovery through injection of a hydrocarbon fluid into the Middle Member of the Bakken Formation (Middle Bakken). The EOR test is planned in two phases:
• 1) cyclic production / injection test
• 2) injector-producer pair test

Cyclic production / injection test (CP/IT)

• two vertical wells
• 32937 (V1): a cyclic production / injection well 
• 32938 (V2): a monitoring well in the first part of the EOR test
• 32937 (V1): middle Bakken; stimulated with a hydraulic, propped fracture to achieve sufficient well injectivity for the test; the test will begin with an initial production period in V1 well to establish a primary production baseline  
• 32937 (V1): after initial production, the V1 well will be converted to an injection well
• 32937 (V1): a hydrocarbon fluid will be injected into the V1 well at rates up to 285 MSCFPD and surface pressures up to 4,500 psig. The injection pressures will not exceed the fracture pressure of the Middle Bakken.
• after the injection cycle is complete, the V1 well will be shut-in for a soak period; then, the well will be converted back to production and produced
• production after the injection/soak period will be compared with the primary production baseline to determine enchaned oil recovery
• 32938 (V2): will be completed in the Middle Bakken; a bottom-hole pressure temperature gauge will be installed in the well for monitoring during the production, injection, and soak cycles of V1;
• 32938 (V2) will not be produced during hte CP/IT

Injector-Producer Pair Test (IPPT)

• the same two wells will be utilized
• V1 will be converted to an injection well
• V2 will be stimulated with a hydraulic, propped fracture prior to conversion to production
  
• a hydrocarbon fluid will be injected into the V1 well at rates up to 285 MSCFPD and surface pressures up to 4,500 psig. The injection pressures will not exceed the fracture pressure of the Middle Bakken. Production response to the hydrocarbon fluid injection will be monitored in the V2 well

The injection facility

• to be onsite, trucked in
• injection fluid will be purchased from the Tioga Gas Plant

Duration of study

• multiple injection, soak, and production cycles, would continue for a sufficient duration to study the impact of hydrocarbon fluid injection on oil recovery
• anticipated duration of the test is 1.5 - 2 years with total gas volume of 90 mmscf (million standard cubic feet)

Impact on other wells

• another Hess-operated well, Nelson Farms 1-24H is located about 1,000 feet from V1
• "due to localized reservoir depletion, a response in the Nelson Farms 1-24H could be expected during the EOR test. The Nelson Farms 1-24H will be monitored daily to detect changes in production. No detrimental impact to production in his well is anticipated because the injection fluid is a hdrocarbon.
• other Hess-operated wells outside the 640-acre RS-Nelson Farms DSU will be monitored for any effect:
• RS-Feldman 156-92-1423H-1 (#17696; middle Bakken)
• RS-State 156-92-3625H-1 (#16800; middle Bakken)
• RS-Lois Enander 156-91-3130H-1 (#17962; Three Forks)
• additionally, produced gas from the RS-Feldman 156-92-1423H-1 (#17696) will be analyzed to ensure that a response in this well could be detected. Due to the much great distance between these wells and the injector (2,800 - 4,000 feet) than the injector and the Nelson 1-24H, it is not anticipated thtat a response in any of these wells would occur. If a response does occur, the NDIC would be notified. Not detrimental impact to production in these wells would be anticipated in the unlikely outcome that a response occurred.

Additional comments:

• test to use 90 million standard cubic feet of natural gas; compare:
• #16800, drilled in 2008, Ross oil field; production through 1/17: 64 million cubic feet of gas
• #24193, drilled in early 2013, Ross oil field, production through 1/17; 69 million cubic feet of gas
• #31000, Robinson Lake oil field, drilled in mid-2015; production through 1/17: 111 million cubic feet of gas

*****************************

Other Sources

Additional sources:

• EOG enhancing Eagle Ford oil recovery using novel natural gas injection system; Natural Gas Intel.com, May 10, 2016; archived.
• public access review of Natural Gas Intel story linked above; May 10, 2016; a must-read

 
"Huff and Puff, ResearchGate.com, 2014, 2015.