Summary With this paper, we introduce an innovative approach for low-cost, rapid detection of gas influx during oilwell drilling by leveraging measurements that can be made using existing technologies, specifically the acoustic logging data from logging while drilling (LWD). The primary contribution lies in introducing an automated method that utilizes real-time acoustic data from LWD and incorporating an analysis approach for interpreting gas influx/kick detection. A description of the methodology used to calculate the acoustic velocity of the fluid mixture based on compressional or shear wave speed and arrival time and the geometric system is presented. The methodology is demonstrated using synthetic data generated from a numerical wellbore model and simulated acoustic wave propagation. Additionally, field data from LWD available in the literature are utilized to further assess the effectiveness of the proposed technique.
Maciel et al. (2026) studied this question.