Evaluation of Fracture Stimulation Performance Based on Production Log Interpretation

Abstract

Abstract Production logging is a traditional approach to monitor an inflow profile in a hydraulically fractured horizontal well. By quantitatively interpreting production logs run in a hydraulically fractured horizontal well, we can evaluate and optimize fracture stimulation design. This paper presents a field example of completion analysis based on production log interpretation. In this well, the fracture treatment design was varied by stage to examine which completion parameters are more influential on productivity. The production performance for each stage was evaluated using an array of spinner flowmeters and phase holdup-sensing devices, and a temperature log. Multiple-sensor array tools were used to measure the phase holdup and local fluid velocity along the wellbore. The cross-sectional area of the wellbore was divided into five segments. The phase distribution of gas, oil, and water within each wellbore segment was assigned based on the phase holdup values along the wellbore. The array spinner flowmeters provided the local velocity inside each wellbore segment. This paper presents a methodology for using data from array production logging tools to interpret the volumetric flow rates of each phase at each interpretation point along the wellbore. The differences in these wellbore phase flow rates provide the downhole inflow distribution along the hydraulically fractured horizontal well. Temperature logs can reveal fluid entry locations as the places where temperature anomalies caused by Joule-Thomson effects occur. When gas is produced, the Joule-Thomson cooling effect as the gas expands in the near-well region generates a cool anomaly that locates the gas entry location. In some cases, the Joule-Thomson heating effect caused by liquid production identifies liquid inflow locations. By performing a temperature history match using a thermal simulator, we quantitatively obtained the gas inflow rates at each active cluster location. This paper demonstrates that the temperature log interpretation provides the inflow profile along the experimental well based on the cooling anomalies. Once we confirm that the inflow profiles estimated by the interpretation of the array production logging tool and the temperature log are comparable to each other, we evaluate the fracture stimulation design based on the production performance for each stage. We present the effect of statistically significant fracture design variables on stage production performance derived from the production log interpretations.