Both interference and pulse tests, also known as multiple-well testing, involve more than one well. These types of tests can be used to obtain reservoir description. At the same time, it is one of the most important and useful tests to understand the well behaviour in a water flood and enhanced oil recovery projects. These tests are used to determine whether two or more wells are in pressure communication in the same reservoir and, when communication exists, to provide estimates of formation permeability and porosity.

Interference is conducted by producing from or injecting into one of these wells (active well), and the pressure response is observed in the other well (observation well). The active well starts producing at uniform pressure at time zero, and the other pressure response in the observation well at a distance from the active well begins after some time lag.

Traditionally, memory gauges were set in an observation wellbore nipple and recovered at intervals to download data. Critical data such as the onset of interference or breakthrough time can be missed, adversely affecting the management of the wells.

Optimum well management requires access to real-time wellbore pressure information, which can be achieved by retrofitting a SonicGauge™ Wireless Monitoring System by slickline or e-line on the Barracuda™ HEX-Hanger™ at any depth inside the tubing. The SonicGauge will deliver real-time data to surface over extended periods, up to several years. At the conclusion of testing, the SonicGauge and Barracuda tools can be retrieved by slickline, redressed and re-run in the next well of interest.



  • Bottomhole pressure transient testing
  • Downhole zonal flow / build-up monitoring
  • Real-time flowing gradient surveys


  • Real-time analysis of well performance
  • Implement changes to well operating point immediately
  • Interference and pulse testing throughout field