Distance between Terra15’s DAS Interrogator and the January 5th earthquake in Western Australia
Terra15 detects first West Australian earthquake of 2022 with DAS system over 180km away
Terra15 has detected another earthquake in Western Australia through its Distributed Acoustic Sensing (DAS) installation in Perth city centre. DAS is increasingly being used for earthquake monitoring because it provides a fantastic opportunity to tap into existing optic fiber infrastructure. This allows geophysicists and seismologists to monitor at a distance and to avoid transmitting real time data from remote locations.
Terra 15 has been using standard telecom fiber cable within the city of Perth and has been able to detect earthquakes as small as magnitude 2 (M2) in Western Australia. Just this year WA experienced a M4 earthquake (equivalent to 15 tons of TNT) with >16 aftershocks ranging between M2 (equivalent to 15 kg of TNT) and M3 (equivalent to 477 kg of TNT) . These events have been successfully detected with the Terra15 “Treble” DAS interrogator.
The sensitivity of the Treble has provided an accurate and instant detection of earthquakes several hundreds of kilometres away even when located in a noisy city environment.
A waterfall plot from real time displays clearly shows P and S wave arrivals over the 7km length of fibre. Here a discreet but measurable moveout can be observed.
Additionally seismic traces of the event show P and S-wave arrivals and is comparative to the data produced by the seismometers. Have a look at the comparison between the trace from a seismometer located 8km from the DAS system in Perth (see below).
Terra15 hopes that using fiber for earthquake monitoring will be standard practice in the future, especially in earthquake prone regions of the world to help coordinate emergency services, guide future building regulations, and save lives. This data can easily flow into the IRIS global database or Geoscience Australia.
If you want to learn more or would like to collaborate with Terra15 please follow the link below and get in touch.
Update: Read the follow up piece to this article discussing how the initial earthquake was a precursor to a rare earthquake swarm and how our Treble DAS interrogators picked up over 60 earthquakes in the weeks following the first event.