Integrating Pulse Neutron Measurements with Array Production Logging for Enhanced Production Characterization in Horizontal Wells

Production logging analysis in horizontal wells can be very challenging due to the fluid distribution and segregation. In addition to this, other factors such as the presence of heavier or viscous fluids, wells with debris or sticky materials add to the complexity of the downhole fluid profiling by causing uncertainty in estimation of phase holdups. This can cause significant errors in calculated flow rates or in some cases rendering most of the production logging sensors ineffective. In order to overcome these challenges, an integrated solution from different measurements is required to optimize downhole fluids profiling. In this paper, the application of Pulsed Neutron (PN) technology to provide a complementary measurement to enhance accuracy of the results is presented. PN technology can be used for independent PN phase holdup and water velocity measurements in near-horizontal wellbores with stratified multiphase flows. Comparison between phase holdups and velocities calculated from ArrayProduction Logging (APL) and PN devices are presented with field examples. Also discussed are the limitations and best practices pertaining to the use of these measurements. The paper details measurements that are not affected by the above mentioned issues. A well- calibrated PN measurement can provide phase holdups as well as water velocity, making it complementary to the APL measurements for characterizing production profiling under challenging conditions.