The Containment and Monitoring Institute (CaMI) has installed Distributed Acoustic Sensing (DAS) optical fiber in two wells and along a trench at the Field Research Station (FRS) in Newell County, Alberta. One of the 350 m deep wells has both straight and helical fibres cemented on the outside of fiberglass casing. Zero-offset vertical seismic profile (VSP) data and walkaway VSP data have been collected along multiple azimuths from this well, using an envirovibe source over a 10-160 Hz sweep over 16 s. Two different interrogators were used to record the data over separate surveys, with both yielding excellent VSP data quality. A comparison of DAS to geophone data has been started through having 24 3C geophones also cemented on the outside of the casing. Some envirovibe shots have been recorded into the 1.1 km long trench fiber with an output trace spacing of 0.25 m. The shot records are dominated by unaliased surface waves.
In addition to the DAS fiber, 100 3C geophones were buried over a 10 m x 10 m grid centered in a CO 2 injection well at the FRS (Figure 1b). These geophones were glued into PVC tubing and drilled to a depth of 1 m below surface. This array will be used for microseismic recording by CaMI at the site and also for some limited imaging.
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