The 2019-20 Dallas Chapter Officers:

PresidentSteve Brackeen (Primexx Energy Partners Corp.), Steve.Brackeen@primexx.com

VP/TechnologyMatt Drouillard (Schlumberger), mdrouillard@slb.com

Secretary, Aaron Green (Lonestar Resources), AGreen@LonestarResources.com

TreasurerMike Caputi (Pioneer Natural Resources), Michael.Caputi@PXD

Chapter Publicist, Jim Lewis(GCC, Great Crew Change), jlewis1@gmail.com

Next Monthly Chapter Meeting:   12 September, 2019,  the 2rd Thursday

 The Dallas chapter will continue to meet in the DeGolyer & MacNaughton sponsored Business Conference Room 'A' located in the Providence Towers building at  5001 Spring Valley Road in North Dallas. Located north of LBJ (I-635), south of Belt Line Road, and on the west side of the North Dallas Tollway, this building has the large open archway in its middle and has a red granite facade. The meeting room is located on the 1st floor of the East Tower. Parking is underground ($1) and can be accessed from either Spring Valley Road or from the southbound service road of the tollway. 

Meetings start at 11:30 for a social gathering, followed by a catered buffet at noon (cost $20, students $10). Please RSVP to:


  by September 9th to ensure that sufficient food is ordered.


Effects of Temperature and Gas Pressurization on the Interpretation of Nuclear Magnetic Resonance (NMR) Hydrocarbon Measurements in Organic Rich Shales

presented by 

Son T. Dang 
 (PhD candidate at the Mewbourne School of Petroleum and Geological Engineering, University of Oklahoma)



The estimation of total hydrocarbons (HCs) in place is one of the most important economic challenges in unconventional resource plays. Nuclear magnetic resonance (NMR) has proven to be a valuable tool in directly quantifying both hydrocarbons and brines in the laboratory and the field. Some major applications of NMR interpretation include pore body size distributions, wettability, fluid types, and fluid properties. However, for tight formations, the effects of the factors on NMR relaxation data are intertwined. One purpose of this study is to review the interpretation of NMR response of HCs in a tight rock matrix through illustrated examples.

When comparing NMR data between downhole wireline and laboratory measurement, three important elements need to be considered: 1) temperature differences, 2) system response differences, and 3) pressure (mainly due to the lost gasses.) The effect of temperature on HCs would be presented with experimental results for both bulk fluids and rock samples. Whereas, the effect of pressure is investigated by injecting gas back into rock matrix saturated with original fluids. The experiments were performed within an NMR transparent Daedalus™ ZrO2 pressure cell which operates at pressures up to 10,000 psi.

The results show that, at a particular temperature and pressure, NMR responds to a fraction of HCs which is volatile enough to be observed as an NMR relaxation sequence. The invisible fraction of HCs to NMR sequence at ambient condition can be up to 25% of the total extractable HCs. Molecular relaxation is impacted by fluid viscosity, pore size, and surface affinity (wettability). In other words, the fluid with higher viscosity (either due to temperature drop or gas loss), presenting in smaller pore, or highly affected by the pore surface, will relax faster, and would be partially invisible to NMR. This is critical to the interpretation of NMR response for liquid rich source rocks, in which all the above molecular relaxing restrictions can be found. Thus, engineers can underestimate movable HCs by using routine core analysis data.

We also demonstrate the novelty of the NMR experimental set-up to monitor real-time recovery of Huff-n-Puff EOR in shales.

Speaker Biography:

Son T. Dang is a PhD candidate at the Mewbourne School of Petroleum and Geological Engineering, University of Oklahoma. He is working as a researcher in the Integrated Core Characterization Center, and a member of OU Unconventional Shale Consortium. His research interests include petrophysics, geochemistry, Enhanced-Oil-Recovery, and spectroscopy analyses on unconventional tight reservoirs.

Meeting Location

Dallas , TX, United States

32° 46' 48.504" N, 96° 48' 1.6236" W

See map: Google Maps

Texas US