Micro-seismic detection using distributed acoustic sensing

Abstract

Distributed Acoustic Sensing (DAS) deployed in a wellbore can be used to detect P-waves and S-waves generated in the subsurface. In a well which has geophones and a DAS cable deployed, micro-seismic events have been detected on both instruments at the same time, establishing the concept of using DAS as a micro-seismic detector. While DAS is still less sensitive than geophones, it has the advantage of being non intrusive and a permanent installation, so both recording in treatment wells and 4D recording concepts are realistic options that can be implemented once the fibered cable is installed.