Permian – Multi-Client PVT Study

Permian – Sample Overview

Last updated: 22 February 2022

Permian – Multi-Client Study

The Permian multi-client project was first initiated in 2019. The main objective of the study was to create one, field-wide equation of state (EOS) model for the entire Permian Basin. Since then more data has been incorporated into the model, resulting in a more robust thermodynamic description. But what is a field-wide EOS model? In simple terms, you can think of it as a field-wide “PVT correlation” applicable for all fluids in a given basin (black oils | volatile oils | near-critical fluids | gas condensates | wet gases | dry gases). The model is tuned/adjusted to measured PVT laboratory data available in that particular basin, and can be used to consistently predict PVT data such as saturation pressures, formation volume factors (FVF), solution GORs/CGRs, densities, compressibilities and viscosities across a field. Here are some key information about the study.

Number of PVT Samples

In this study, 156 PVT samples from 128 different well locations were included in the EOS model development work. Of the 128 wells, 92 are located in Delaware Basin, 35 are in Midland Basin, and one well in Northwest Shelf. There is no dry gas sample in this study, while the number of bubblepoints and dewpoints samples are 96 and 60 samples, respectively. The C7+ component is ranging from 3 mol% to 51 mol%. The production comes from Wolfcamp, Bone Springs, Avalon, and Spraberry formation, with recombined GOR ranging from 219 -20,000 scf/STB. The Permian samples are thermodynamically consistent, even though the compositions tend to vary, meaning that one EOS model is sufficient.

Participating Companies

New companies are joining the study every single year.

  • Ameredev
  • Blackstone (Guidon, Primexx, Jetta Permian)
  • BPx
  • Conocophillips (Concho)
  • Continental
  • Coterra (Cimarex)
  • Diamondback
  • Endeavor
  • EP Energy
  • ExxonMobil
  • Laredo
  • Marathon Oil
  • Oasis
  • Ovintiv
  • Oxy (Anadarko)
  • Pioneer

Unconventional Fluids Systems

Unconventional fluid systems demonstrate strong field-wide PVT consistency although the reservoir fluid (i.e. composition) varies significantly. Reservoir fluid differences are dominantly determined by thermal maturity, which is the main reason behind the consistent fluid characteristics over large areas. What this means in practice, is that we can use one fluid model (i.e. EOS model) for the entire field, but what changes from area-to-area/well-to-well is the GOR (i.e. composition). This has been one of the key findings in all our studies.

Which Unconventional Basins Have We Conducted This Type of Work?

  • United States
    • Eagle Ford / Austin Chalk – Texas (Multi client)
    • Permian (Midland & Delaware) – Texas & New Mexico (Multi client)
    • Anadarko Basin (SCOOP/STACK/Merge) – Oklahoma (Multi client)
    • Bakken – North Dakota (Multi client)
    • Utica Basin – Pennsylvania (Multi client)
    • Arkoma Basin – Oklahoma (Single client)
  • Canada
    • Montney, Alberta & British Columbia (Multi client)
    • Duvernay, Alberta (Multi client)
    • Garrington, Alberta (Single client)
  • Rest of the world
    • Jafurah basin, Saudi Arabia (Single client)
    • Vaca Muerta, Argentina (Single client)

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