Abstract: An influx of gas into a borehole can be detected by deploying a string of acoustic sensors along a drill string or other conduit to monitor an acoustic characteristic, such as velocity or attenuation, of the drilling fluid present in the borehole. In response to detection of acoustic pulses propagating in the drilling fluid, the acoustic sensors generate signals that are representative of acoustic characteristics if the drilling fluid. Based on the generated signals, a data acquisition system can determine whether a change in the monitored acoustic characteristic is indicative of a gas influx.

Abstract: An influx of gas into a borehole can be detected by deploying a string of acoustic sensors along a drill string or other conduit to monitor an acoustic characteristic, such as velocity or attenuation, of the drilling fluid present in the borehole. In response to detection of acoustic pulses propagating in the drilling fluid, the acoustic sensors generate signals that are representative of acoustic characteristics if the drilling fluid. Based on the generated signals, a data acquisition system can determine whether a change in the monitored acoustic characteristic is indicative of a gas influx.