- Correlation seismology and application to the structure of the deep Earth.
- Characterization of anisotropy in the Earth’s inner core
- Global seismic imaging of upper mantle discontinuities and geodynamical implications
Anisotropy in the Earth’s inner core using coda-correlation wavefield:
Eighty-five years ago, Inge Lehmann discovered seismologically that the Earth has an inner core (IC). Today we know that the IC is a solid sphere mainly composed of iron-nickel alloy. The IC comprises only 0.7% of the volume of the Earth, and its surface is more than 5000 km beneath our feet, making investigations of its physical and chemical properties extremely challenging. The most powerful way to map its interior is using seismological tools – energy from earthquakes that travels through its structure. However, due to the lack of seismic data sensitive to the IC, many of its properties are unknown or not fully constrained. One of these properties is its seismic anisotropy – the directional dependence in sound wave velocity. Improved constraints on anisotropy are required to understand the crystallographic structure of iron stable at the IC’s temperatures and pressure. Therefore, anisotropy in the IC holds the key to understanding the Earth’s evolution and the magnetic field harboured in the liquid outer core.
During my Ph.D., I have been working on developing and applying different techniques to probe the Earth’s innermost region. The first research question I aimed to answer is: can we derive a new method to probe the center of the IC and overcome the current shortage of seismic data sampling its structure? Secondly, what additional constraints can we obtain on the IC anisotropy?
We just submitted my first paper, and hopefully, you will be able to read the answer for those questions in a near future! Stay tuned!
Joint inversion of receiver functions and surface-wave dispersion using a bayesian framework:
Before my PhD, I came to Australia to visit RSES and do a research internship. During those valuable months, I’ve had the chance to explore Bayesian inversion of receiver functions and surface wave dispersion data from teleseismic earthquakes to provide constraints on the crustal depth beneath the Borborema Province (BP), northern region of Brazil. That was my first experience working with seismology, and undoubtly, I faced a steep learning curve as I had to familiarise myself with many new concepts, in particular at coding. During my studies, I used a new probabilistic framework to perform a highly efficient joint inversion of receiver functions and surface wave dispersion data to investigate the shear-wave velocity models beneath the receivers. To know more, you can download the full PDF of our extented abstract >>>>> here.