Abstract
Successful steam operations in thermal recovery are a function of reservoir quality, steam distribution in injection wells, temperature distribution in production wells, and hydrocarbon mobility, so it is important to include reservoir monitoring to provide critical information of the subsurface for effective operations. Real-time well data profiles benefit project economics, safety, and viability by monitoring downhole temperature, pressure, and acoustic data. As such, an advanced coiled tubing based survey string designed for thermal, as well as EOR, well surveillance has been recently introduced in Oman. The survey string incorporates 315°C rated instrumentation by integrating fiber optics, point pressure and temperature sensors, and e-line within coiled tubing to allow data acquisition under live well conditions. Data profiles are graphically presented through a graphic user interface where locations of steam injection, pressures, and fluid ingress points can be interpreted. This representation can assist in production optimization, determining existence and locations of mechanical failures due to steam break through and subsequent liner wash-out to the slotted liners, and immediate identification of downhole heat sinks and reservoir heterogeneities affecting steam chamber development. Advances in integrating real time, full wellbore fiber optic data allows new insight especially when applied in horizontal wells under live operating conditions. This data demonstrates a significant advancement in thermal well surveillance. Novel high temperature well control technology and completions design enable live well surveys in dynamic thermal production and steam injection wells. This paper will review key aspects of the tool qualification for live thermal well surveys. Example data shows the ability to locate and track the flow of fluids and characterize the reservoir response to well operations.
