Optical Fiber Sensor Based Transportable Active Seismic Survey System Solution to OSI

Abstract

Active seismic surveys, together with passive seismic monitoring surveys, magnetic and gravitational field mapping and electrical conductivity measurements (Protocol to the Comprehensive Nuclear Test Ban Treaty (CTBT), Part II), are geophysical detection technologies that can contribute jointly to the search logic for the detection of On-Site Inspection (OSI) underground anomalies or artifacts. This work has carried forward a system solution to active seismic surveys based on optical fiber sensor arrays, which in general meets the technical requirements of OSI equipment list. The system consists of 800 channels (up to 1000 channels) that include three component seismic geophones working in the frequency band 5–500 Hz (up to 1–1000 Hz). The vehicle engine driven power system can support several days of operations and the storage capacity can support several days of measurements. Fast Flexible Convolutional Neural Network (FFCNN) deep learning noise reduction method has been applied to weak signal recognition. A user-friendly 2-D/3-D human–machine interactive data interpretation software platform has been developed for the data visualization and analysis. This system is adaptable to any seismic sources, such as explosives, vibrating sources, weight drop and sledgehammers. This system has been tested and verified in the field and can be suitable for future OSI activities.