Advanced logging technologies in reservoir crossflow detection

Crossflow exists when there are zones with dissimilar pressure properties allowed to communicate during production. Reservoir fluid from a high-pressure zone will flow preferentially to a low- pressure zone except if the production parameters are well controlled. In a multi-layer producing reservoirs, the crossflow is often related to a poor cement bonding that creates unwanted conduits behind casing. The reservoir crossflow can cause several production problems including zonal allocation, production performance and reservoir variables, potential reduction in recovery factor, and sanding problem. Several cased-hole logging tools have been introduced to detect the crossflow including Production Logging Tool (PLT), High Precision Temperature (HPT) and Spectral Noise Logging (SNL). The technology evolvement is meant to ameliorate the previous tools in crossflow detection. This paper discussed the advanced technologies in crossflow detection starting from the beginning.