Low permeability measurements on small samples and drill cuttings.

  • Interpretation of a gas pressure drawdown (improved GRI method).
  • Precision is under the nanoDarcy and up to 500 nanoDarcy.

DarcyShale™ Brochure

DarcyShale Commercial Brochure


  • The samples are put under pressure in a small chamber.
  • The pressure is quickly decreased  by opening a valve in a second chamber.
  • Permeability is derived from the interpretation of the transient pressure.

A benchmark on several commercial measurements using the standard Gas Research Institute method has shown several problems (SCA 2019). A collaboration between TOTAL and CYDAREX has improved the GRI method and the equipment (SCA2021):

  • Sample initially under pressure allowing a small variation of pressure inside the sample for a better determination of Klinkenberg correction.
  • Filling of the empty space with a fine powder to reduce thermal effects linked to the decrease of pressure.
  • Filling of the drawdown vessel for better temperature regulation with metallic chips.


  • Mass of samples between 2 and 5 grams, single sample or granular.
  • Cuttings  or crushed samples with 1mm minimum size.
  • Pressure up to 40 bar.
  • Permeability on crushed samples below the nanoDarcy, and up to 500 nanoDarcy.
  • Numerical interpretation with single or double permeability models.
  • Automatic history matching using the software CYDAR.
  • Fast and easy measurement.


  • SCA2010-32: Permeability measurement on small rock samples, Lenormand, Bauget, and Ringot.
  • SCA2019-016, Low permeability measurement on crushed rock: insights, Profice and Lenormand.
  • SCA2021: to be published.