Speaker: Voon Hui Lai, Australian National University
Title: Advancing Fault and Coastal Monitoring with Fibre Optic Sensing
Time: Monday, Oct 20 at 1:00pm PST
Location: EMS C332
Abstract: Understanding and monitoring environmental hazards, ranging from catastrophic events like landslides and debris flows to gradual processes such as ground subsidence, requires high-resolution, long-term observational data. However, these processes often evolve over long timescales and exhibit strong spatial variability, making them challenging to capture with conventional sparse geophysical sensors. Distributed Acoustic Sensing (DAS) is a new fibre-optic sensing technology that can transform environmental and hazard monitoring by repurposing telecommunication fibre-optic cables into dense seismic sensor networks. DAS enables continuous monitoring over tens of kilometres with metre-scale resolution, offering unprecedented detail of Earth’s subsurface and new insights into its dynamic processes.
In this talk, I will present my recent research utilising DAS on existing telecommunication cables in New Zealand, integrating advancement in passive imaging to reveal fine-scale structural variations within the Alpine Fault zone and their implications for fault permeability. Additionally, I will demonstrate how the high spatial and temporal resolution of DAS enables new characterizations and hence new insights into under-observed alongshore coastal processes such as breaking waves. These observational and methodological advancements lay the foundation for long-term environmental and hazard monitoring in fragile, difficult-to-access regions such as urban and submarine environments.
The seminar will conclude with a short discussion on how fibre-optic sensing technology is driving the transition toward big data geophysics and the approaches being developed to address this challenge in Australia.
