Well and Overburden Monitoring Using Distributed Acoustic Sensors

A system for detecting a leak event within a wellbore, the system comprising

• a receiver unit comprising a processor and a memory, wherein the receiver unit is configured to receive a first signal from a sensor disposed in a wellbore, wherein a processing application is stored in the memory, and wherein the processing application, when executed on the processor, configures the processor to:
• receive the first signal from the sensor, wherein the signal comprises an indication of an acoustic signal received at one or more depths within the wellbore, wherein the signal is indicative of the acoustic signal across a frequency spectrum,
• receive a second signal comprising an indication of an induced pressure differential within the wellbore,
• determine a plurality of frequency domain features of the acoustic signal across the frequency spectrum, wherein each frequency domain feature of the plurality of frequency domain features are derived from across the frequency spectrum,
• compare the plurality of frequency domain features to a leak event signature,
• determine a presence of a leak event at one or more depths within the wellbore based on the plurality of frequency domain features matching the leak event signature at one or more depths in the wellbore,
• correlate the leak event with the induced pressure differential,
• determine a presence and location of a leak within the wellbore based on the presence of the leak event and the correlation of the leak event with the induced pressure differential, and
• generate an output indicative of the presence and location of the leak event.