Lead supervisor: Adriano Gualandi, Earth Sciences
Co-supervisor: Alex Copley, Earth Sciences; Lauro Chiaraluce, Osservatorio Nazionale Terremoti, Istituto Nazionale di Geofisica e Vulcanologia (Rome, Italy)
Brief summary:
Near Fault Observatories (NFOs) provide abundant multiparametric data in tectonically active regions and offer a great opportunity to better understand the physical processes responsible for earthquakes
Importance of the area of research concerned:
There are six Near Fault Observatories (NFOs) in Europe that provide invaluable multidisciplinary data collected near active fault systems. Some of the monitored faults can produce large earthquakes (M7). The NFOs’ cutting-edge infrastructures allow us to monitor at high resolution the seismic, geodetic (with GNSS and strainmeter data) and geochemical (CO2, Rn) activities. In some cases, thanks to the networks’ spatial density, it is possible to reach completeness magnitude of about 0 and to detect geodetic tectonic displacements of a few mm. This makes the NFOs ideal candidates where to test hypothesis regarding the triggering of seismicity (e.g., by surface hydrological load). The data coming from NFOs will be pivotal to better constrain the hazard associated with active faults and what are the mechanisms leading to earthquake nucleation in different tectonic environments. Ultimately, this information can help mitigating the seismic risk of these densely populated regions. The techniques used/developed in this project will be applicable to other similar infrastructures (e.g., the San Andreas Fault Observatory at Depth, SAFOD, near Parkfield).
Project summary :
This project will focus on the study of different datasets with the goal of unravelling the interconnections between the different observables. A primary goal will be to quantify the repartition between seismic and aseismic slip on the complex network of active faults. This will enable to provide constraints to the moment budget and allow us to better assess the seismic hazard. Particular attention will be spent on the characterization of non-tectonic signals in the observables. For example, over-pressurized fluids have often been invoked to explain seismic swarms in some of the regions (e.g., the TABOO NFO), and geochemical and meteorological data will be used to better understand the role of fluids on the seismic activity. On that regard, collaborations with the Istituto Nazionale di Geofisica e Vulcanologia (INGV) will be carried on.
What will the student do?:
The student will perform a spatio-temporal analysis of available seismic catalogs, will extract the tectonic signal from geodetic time series (GNSS and strain) and invert for it to retrieve slip on the active faults. He/She will also have the opportunity to work on the relationship between observed degassing and active tectonics. The student will explore the causal relationship between the different observables using nonlinear dynamical system tools suited for the study of complex systems. Some of the methods will involve the application of Machine Learning and multivariate statistic techniques. While the project will primarily be focused on European NFOs, other infrastructures can potentially be investigated where multiple observables are available.
References - references should provide further reading about the project:
Chiaraluce, L., Festa, G., Bernard, P., Caracausi, A., Carluccio, I., Clinton, J.F., Di Stefano, R., Elia, L., Evangelidis, C.P., Ergintav, S., Jianu, O., Kaviris, G., Marmureanu, A., Šebela, S., and Sokos, E. 2022. The Near Fault Observatory community in Europe: a new resource for faulting and hazard studies. Annals of Geophysics, vol. 65, no. 3, DM316, doi:10.4401/ag-8778.
Gualandi, A., Nichele, C., Serpelloni, E., Chiaraluce, L., Anderlini, L., Latorre, D., Belardinelli, M.E. and Avouac, J.-P. 2017. Aseismic deformation associated with an earthquake swarm in the northern Apennines (Italy). Geophys. Res. Lett., vol. 44, doi:10.1002/2017GL073687.
Zoback, M., Hickman, S., Ellsworth, W. and the SAFOD Science Team. Scientific Drilling Into the San Andreas Fault Zone —An Overview of SAFOD’s First Five Years. Scientific Drilling, vol. 11, pp.14-28, doi:10.2204/iodp.sd.11.02.2011.
Applying
You can find out about applying for this project on the Department of Earth Sciences page.