Rock Core Analysis

Rock Core Analysis

Oxford Instruments’ rock core analysers are in use worldwide, with almost every major oil company and oilfield services provider as well as many independent core analysis laboratories.

Low field NMR is routinely used in the oil exploration industry to examine the T2 relaxation time distribution of fluids in core plugs. These distributions can be further interpreted to give information on pore size distributions, permeability, porosity, free fluid index and bound water volumes.

Instruments for routine measurements of relaxation distributions generally operate at 2MHz, in order to reduce artefacts caused by ferromagnetic material in the samples, and to mimic the operation of the NMR logging tools.

For more advanced research into rock core fluid properties, a number of additional options are available. These include:

• Pulsed field gradient options for wettability and diffusion studies.
• “Pseudo-static” gradients - pulsed field gradients with the capability for long gradient pulses such that the gradient appears static during the NMR scan.
• Higher field magnets for MRI applications 
• Sample probe sizes up to 150mm diameter (100mm with magnetic field gradients)
• Through-hole probe designs to facilitate the use of core holders for elevated temperature and pressure measurements (special NMR-compatible core holders are available from suppliers including Temco and Ergotech).