[S-CG44] Science of slow-to-fast earthquakes

[SCG44-15] Recent developments on distributed fiber-optic sensing for long-term geophysical monitoring

★Invited Papers

*Ge Jin¹ (1.Colorado School of Mines)

Keywords:distributed fiber optic sensing, Earthquake monitoring, long-term strain monitoring

Optical Time Domain Reflectometer based Distributed Fiber-Optic Sensing (DFOS) technology converts a regular telecommunications fiber into a dense sensor array. As a subset of DFOS, Distributed Acoustic Sensing (DAS) and Distributed Strain Sensing (DSS) technologies can measure strain distribution along a fiber with high spatial and temporal resolutions. DFOS-based strain measurements have a very broad frequency spectrum. Depending on measuring methods, DFOS can be used to monitor long-term (days to months) deformation as well as strain changes induced by thousands of Hertz vibrations. It also enjoys sub-micro strain sensitivities thanks to recent improvements in instrument designs.
This presentation introduces measuring principles and geophysics applications of different types of DFOS-based strain measurements, including DAS and two types of long-term DSS. First, I will showcase the recent developments on DAS-based earthquake and microseismic monitoring, and discuss the advantages and disadvantages of DAS-based seismic monitoring systems. I will then review long-term DSS monitoring, including hydraulic fracture geomechanical monitoring and landslide monitoring. I will conclude the presentation by discussing the opportunities of using DFOS measurements to monitor slow and fast earthquakes.