Earthquakes affect many highly populated areas around the world so understanding what controls the distribution and frequency of them is a top priority for the earth science and disaster risk reduction communities. Often, however, the controlling factors remain elusive because scientists have limited information about what happens deep down in the Earth’s crust where earthquakes initiate. A recent Nature Geoscience article (Cowie et al. (2013) published online on 3rd November, 2013) has shed light on the problem, and has shown how phenomena on the surface can be linked to the movement of rocks in the deep crust.
With the 4-year anniversary of the devastating L’Aquila earthquake occurring in the middle of my first PhD fieldtrip to Italy, the importance of studying active faults in the Abruzzo region remained at the front of my thoughts throughout my trip. The aim of the trip was to use Laser scanning (LiDAR) and ground penetrating radar (GPR) to increase our understanding of the active earthquake faults in the area. The group comprised Dr. Joanna Faure Walker (UCL IRDR), Dr. Ken McCaffrey (Durham University) and Dr. Laura Gregory (University of Leeds).
The first week was spent collecting GPR and LiDAR data along active faults, while the second week was spent hunting for potential future data collection sites. The active normal faults in this area can be seen in the landscape due to the existence of prominent limestone bedrock fault scarps on the side of steep mountains. However, such fault scarps are not present everywhere; for example, part of the fault responsible for the 1915 Avezzano earthquake that killed over 30,000 people crosses the Fucino plain. The Fucino basin is a former lake bed that was drained in the 1800’s. Consequently, the fault scarp has been obscured by erosion from the lake and more recently by intensive farming. LiDAR scans of sites along the fault trace within the plain ensure that we have a 3D digital image of the current state of the fault.
During the course of the two-week trip I visited 10 active faults across the region of Abruzzo and collected large quantities of data to process over the coming months. Visiting the faults for the first time was invaluable to my understanding of the earthquake hazard and overall seismic risk that people in the area are subject to. Observing spectacular villages that cling to the sides of mountains located in the hanging walls of active faults and larger towns in the basins below highlighted the potentially devastating impact earthquakes in the area could have. The results of my work will feed into a larger NERC funded study which aims to determine the time since each active fault last produced an earthquake; being a first year PhD student, this is a fantastic opportunity for me and I am looking forward to contributing to such an innovative and exciting project.