I am currently a Senior Research Fellow at the Earth Observatory of Singapore. I am studying the impact of large subduction zone earthquakes on vertical land height changes. My research is part of a larger project studying relative sea-level change in South East Asia. I am interested in earthquakes, remote sensing, international development, climate change and disaster risk reduction.
In my spare time I love hiking and travelling, see my travel blog: ostrichtrails.com.
University of Cape Town PostDoc Projects:
Namibia: I am using aerial imagery, satellite and aeromagnetic data, to compile a GIS database of active faults. I am using SRTM DEM data to find vertical and/or horizontal offsets along these fault scarps, to estimate the magnitude of earthquakes that formed them, and so better understand the future potential hazard.
Fennoscandia: I developed an algorithm in R to automatically find vertical offsets along fault scarps using recent high-resolution LiDAR DEMS. Using the results, I studied the variability of offset along these faults, and compared their average offset to length ratios with other earthquakes around the globe. I used spatial datasets of Quaternary cover (i.e. till, peat, sand) to see how these affected the offset, and found as expected, that more easily erodible materials such as sand had on average lower offsets. The high variability of offset I found has implications for uncertainties in paleoseismic studies and ground-motion prediction equations, which feed into seismic hazard. The offset to length ratios are also important in estimating the magnitude of past earthquakes where we do not have an instrumental record.
Tibetan Region: I compiled and cleaned a GPS dataset from literature sources, and used this to make a strain rate map of the region. I wanted to compare the strain rate with earthquake mainshock rate. To do this, I declustered the catalogue i.e. removed aftershocks etc. and tested whether the remaining earthquakes followed a Poisson distribution in both time and space (i.e. complete spatial randomness), which they did. The strain rate showed linear correlation with the earthquake mainshock rate, meaning that assuming moment balance, the largest earthquake needed independent of the strain rate. I used these findings to develop a new, simple, globally applicable and easily updateable method for probabilistic seismic hazard.
Malawi: I am looking at the structure of faults in the crust, and the depth of seismicity. I was part of a team that deployed 20 geophones in southern Malawi for a period of three months. I analyzed the resulting waveform data to detect and locate the earthquakes using ObsPy (Python package), SEISAN and R. I found that seismicity extends all the way from the surface to roughly 35 km depth – near the base of the crust, unlike in other extensional regions where seismicity stops at 15 km depth. The wide seismic zone I found implies that larger earthquakes could rupture may have a very wide width, allowing them to reach larger magnitudes that would be the case elsewhere.
Bhutan: I created a new probabilistic seismic hazard map, based on GPS data, earthquake catalogues and previous studies of paleoseismicity in the region. A colleague used my results and their knowledge of building fragility to develop a probabilistic seismic risk map for the region.
Before the University of Cape Town, I worked for RMS (Risk Management Solutions) – a catastrophe modelling company, where I was in the risk management consulting team based in London. Previous to this job I spent 9 months as a research assistant at the University of Cambridge, living and working in Kathmandu, Nepal. There I worked with NSET, an NGO, to create a new seismic hazard map of Nepal, using probabilistic seismic hazard analysis. Click for my article and website about seismic hazard in Nepal. I spent three months as an intern at the United Nations, Bonn, working at UNSPIDER to develop a method to forecast drought in the Limpopo Basin, South Africa.
I completed a PhD in geoscience, specializing in earthquakes, at Caltech, USA. Before that I studied at the University of Cambridge, UK, where I obtained a Bachelors and Masters in Natural Science, specializing in geology.