Silixa’s ArrayLog™ service provides well integrity monitoring using legacy fibres

Good well integrity is vital to eliminate the risk of uncontrolled release of formation fluids throughout the life of the well.  Our ArrayLog™ services utilise distributed acoustic (iDAS™) and distributed temperature (ULTIMA™ DTS) data to detect fluid movement.

When well parameters point to the failure of a barrier it is necessary to identify the source of the failure in order to plan remediation, or to demonstrate the continued integrity of the barrier for normal operations. Distributed fibre optic sensing offers a unique way to quickly and efficiently detect the fluid movement which may indicate barrier failure.

The iDAS and ULTIMA DTS can detect leaks or flow behind casing without the need to intervene in the well, utilising pre-exisiting  fibre optic cables. The optical fibre behaves as a sensor array so the entire fibre path is surveyed simultaneously allowing well integrity issues at undetermined depths to be detected and localised almost immediately.

Key benefits

  • Rapid leak detection by scanning whole well with a single sensing array
  • Real-time software enables rapid conclusions and optimises operating time
  • Intervention-less technique, using legacy fibres


  • Tubing to annulus communication detection
  • Identify and confirm leaking completion components such as valves and plugs
  • Detect fluid movement behind casing and track to origin
  • Listen continuously for signs of cap rock failure during injection or disposal of CO2
well integrity

With an optical fibre cable placed in an abandoned well, the iDAS was able to listen continuously over a period of several hours and subsequently capture a single discrete event signalling the periodic release of accumulated gas pressure behind casing. Unlike point sensor leak detection, the distributed nature of the iDAS measurement ensures that all such events are captured.