Every year in CoS, dozens of PhD students defend their thesis and earn their doctorate, the highest university degree. In this series, we catch up with some new doctors to find out about their experience of doing a PhD in CoS, what made them embark on the intense four year journey and what plans they have for the future. Next up, we have Dr Stephen Pansino, a Research Fellow with the Earth Observatory of Singapore (EOS).
From the violent eruptions of active volcanoes, to the explosive lava fountains that bear a surprising resemblance to the aftermath of shaking soda bottles, to the powerful magma flows carving pathways to the earth’s surface, Dr Stephen Pansino has had, since his high school days, an abiding fascination with all things volcanic.
Following an undergraduate degree in mechanical engineering from the University of Pittsburgh and a master’s degree in geology from the State University of New York at Buffalo, Dr Pansino joined the Interdisciplinary Graduate School at NTU in 2014 to pursue a PhD. Under the supervision of Asst. Prof Benoit Taisne, he studied the variety of behaviours associated with magmatic dike propagation. In October 2019, he successfully defended his thesis, titled An Experimental Approach to Dike Propagation: The Effects of Stress, Solidification and Internal Flow. We caught up with Dr Pansino, now a Research Fellow with the EOS, to ask about his experience as a PhD candidate and his ongoing research on dike propagation.
What are you currently working on?
My PhD (and my current work still) was focused on magmatic dike propagation, which is the study of magma-filled cracks in the earth. The cracks grow upwards, towards the surface, allowing magma to ascend and erupt. I do this using small, lab-scale experiments, by injecting liquids like vegetable oil or water into a block of solid gelatin. The idea is that we design the experiment to be a smaller, simpler version of what actually happens in nature. I pay attention to how the liquid flows, the subsequent shape of the crack that forms and how the surrounding gelatin deforms.
A dike (in red, viewed from the front) made by injecting warm, liquid gelatin into cold, solid gelatin. The dike erupted at the surface. Afterwards, the liquid gelatin cooled heterogeneously, forming a central liquid pathway (the narrow, darker feature). The remaining dike solidified.
Why did you choose to do a PhD, and how did you decide on your research area?
I chose to do a PhD because I wanted to make a career out of studying volcanoes. When I first started working with Asst. Prof Benoit Taisne, he knew I liked to do lab experiments (I had done them in my Master’s research) so he had me begin with investigating dikes, which he studies. I like the topic because liquid-filled cracks aren’t something that you typically encounter in real life. The first time I conducted an experiment, I was amazed by how strange and mesmerizing they were. These liquid-filled cracks are really important in understanding how volcanoes erupt, so the research has a lot of scientific merit as well.
Gif of an oil-filled dike growing through gelatin towards an inflated balloon. The rainbow pattern shows how the gelatin is stressed by the balloon. The deflatingof the balloon causes the dike to abruptly change direction and move tangentially. The dike responds to the compression or extension by the balloon.
How did it feel to receive your PhD degree?
The PhD is very much like a marathon, so I was proud and relieved. Doing a PhD builds up your understanding of your topic very gradually, so I had thought, initially, that there would be no change in how I felt before and after the defence. But upon reflection I can see that I’ve come a long way.
Could you explain simply how your research on dike propagation has contributed to existing knowledge?
The best part of my research is that everything that happens in an experiment is visible. We can literally watch a dike grow inside the gelatin and see how it responds to solidification or external pressure. My research is the first to quantify some of these factors, but what’s even better is that its resulted in some very nice visuals that make it easier to communicate with others.
How do you think your findings can be applied in the future?
The end goal of my research is to perfectly understand the physics of how magma moves underground. The first step was creating simple experiments that you can also measure very precisely. Now, I compare the findings to past eruptions to see how things match up. Eventually, I’d like to have a predictive tool, in order to perfectly forecast how future dikes will behave.
Your research approach seems to be quite hands-on. Has the experimental nature of your research process been rewarding?
My favourite part of my work is being in the lab and performing experiments. They are always interesting and fun to do. Sometimes I have no idea what will happen and when I watch the experiment, it feels like I’m the very first person in the world to see what I’m seeing.
What was the most challenging aspect of pursuing a PhD, and how did you overcome it?
The hardest part for me was learning time management, especially during the first two years, when I had to divide my time between classes, teaching and my research. I’m better now at organizing and prioritizing my tasks, but there’s always room for improvement.
How did the actual PhD defense go?
I remember my throat being very dry and I had to ration the contents of my water bottle! Otherwise, I felt in control. After so many years of thinking about my topic, I knew the material very well and could present it confidently and discuss it with the audience.
What are your next steps?
I’m looking to start a post-doc research project in another university. I’d like to do one or two more of such projects and then hopefully move on to a job either in government or academia.
Do you have any advice for new or prospective PhD students?
Be protective of your downtime. Doing a PhD is like running a marathon, so you need to periodically take breaks or you’ll burn out.