Earth and Environment from Fiber Optic and Seismic Wave Analyses

Project Rationale:

Much of our direct imaging and understanding of Earth’s subsurface comes from data collected by relatively sparse deployments of seismometers. The same is true for our understanding of Earth’s oceans which are monitored with sparse oceanographic instrumentation. Recently, fiber optic cables have been used to record ground motions related to a variety of sources including earthquakes, man-made sources, ocean waves, and more. These cables have enormous potential to increase and enhance imaging and understanding of the Earth and the oceans given that they record on long time scales and be deployed over vast swaths of the earth. However, much of the potential has yet to be fully investigated and realized. Here we will use their potential in a wide variety of disciplines to solve some of the outstanding and fundamental challenges and questions in earth science across a range of disciplines including but not limited to ocean wave propagation, earthquake source investigations, and the interior structure of the Earth including the crust and the mantle, and potentially deeper. There are broad implications for plate tectonic theory, climate, and hazard.

Methodology:

The project will involve investigation of signals recorded on fiber optic cables by a distributed vibration sensing (DVS) interrogator and comparison to signals recorded on more traditional equipment such as geophones, seismometers, pressure recorders and buoy data. The student will use data collected in a variety of environments including but not limited to beaches, shallow marine, deep sea and terrestrial. Although we already have abundant data available for analyses, there will also be field opportunities to collect new data. A range of seismic data techniques will be employed that could include for instance, classic active source reflection and refraction imaging, earthquake detection and location, and tomographic imaging of Earth’s interior using earthquake sources. For oceanographic applications, spectral analysis, and frequency-time analysis techniques will be used to explore the relationships between environmental signals such as ocean waves and fiber optic recordings.

Training:

The INSPIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at the Graduate School of the National Oceanography Centre, University of Southampton. Specific training will include:

The student will develop skills and learn techniques from seismology as a member of one of the largest and most active geophysics groups in the UK. The student will learn to cull, process, and invert seismic data using dense seismic arrays. The student will learn cutting edge skills in a wide variety of fiberoptic techniques. The student will have excellent computational facilities and be trained in programming skills for Python, Seiscomp3, FORTRAN, Matlab, SAC, and the UNIX operating system. The student will integrate the results in a broad interdisciplinary approach. A wide range of opportunities to develop the range of generic skills essential for successful completion of the PhD and their future career are available through the Graduate School NOCS including geophysical fieldwork. The project will involve collaborative international travel. This training will prepare the student for a career path in academia and industry.