Optic Fibres for Seismic (VSPs)
Optic fibre DAS VSP data from MSDP 15 showing two-way-travel-time vs. depth. Reflectors (highlighted in green) align with major breaks in the geological log. The red curve is the derived P-wave interval velocity.
We have successfully acquired a vertical seismic profile (VSP) using optic fibre DAS (distributed acoustic sensors) in the diamond drill hole at the Port Augusta coiled tubing drilling trial (MSDP 02) and a nearby hole (MSDP 15). The DAS data were collected ~ 5 times faster than our previous collection of a hydrophone VSP in MSDP 02. It also delivered higher quality data with more consistent amplitudes, less tube and cable waves and clearer reflections. The low cost and high quality of optic fibre DAS provides the potential for VSP in every drill hole for petrophysical characterisation and seismic monitoring.