In this post, Dr Geoff Bromiley, a Reader in Experimental Geoscience within the School of GeoSciences, describes an inspiring experience of teaching-led research…
Research-led teaching is something we often hear about at university. We rightly flag this as a great reason why students should study at The University of Edinburgh. It’s better to be taught by the person who wrote the book, rather than someone who is reading it like you. That person could be the scientist who discovered a new species of dinosaur that redefines what we know about evolution; it could be someone developing high-temperature superconductors which will revolutionise industry; or it could be the person who uses the most powerful lasers on Earth to simulate extreme pressures. These people are all world-leading researchers who teach at The University of Edinburgh.
What we don’t often hear about is teaching-led research. During my 10 years at Edinburgh, I’ve grown to realise that teaching is a two-way flow of information. Good teaching is dialogue. As the saying goes, “to truly understand something you need to teach it”, but the advantages of teaching go far beyond that. At Edinburgh, we have gifted students from all over the world, with diverse backgrounds, experiences and training. They ask tricky questions. Lots of tricky questions. They want to understand things in detail, and place ideas and understanding in context. They raise points that you would never have considered, and make connections between subjects that can be both surprising and enlightening.
Classrooms have a collective intelligence and experience that can really test you as a teacher, and many of the most stimulating scientific discussions I have had over the past 10 years have been with students. An example of this is a conversation I had with students on a small hill next to a chicken farm in Cyprus, which rapidly moved onto a discussion about super volcanoes on Venus.
Every year, we take our 4th year Geology students to Cyprus for two weeks. Geology, like other Earth Sciences, is an applied subject. We apply knowledge from all branches of science to study the Earth (and other planets). You can’t teach subjects like this by staying in the classroom. Lectures, labs and tutorials are great places to introduce topics, but to properly train as an Earth Scientist you have to get outside. The world around us is the ultimate teaching space, and at Edinburgh we use it as much as we can.
Cyprus is great in this regard. The centre of the island is a chunk of ancient seafloor, which formed over 60 million years ago. During the field trip, we travel all over the island to understand how this slice of ocean crust formed. At one point, we make a short detour near the village of Marki to look at a strange, lumpy hill, known (to us at least) as Picrite Hill. Picrite is a type of volcanic rock. Not unusual at all, but the picrite here is stuffed full of large, green olivine crystals (the gemstone peridot).
Our students spend time clambering over Picrite Hill making observations and trying to understand how it formed. They’re really good at solving geo-puzzles like this. The Cyprus field trip runs at the end of 4th year, so the class collectively has over 30 pairs of expert eyes scouring the landscape, picking up all available clues. What they find is a real head-scratcher.
All the evidence suggests that Picrite Hill formed by eruption of sticky, crystal-rich lava. This was squeezed onto the ancient seafloor like toothpaste, forming a large volcanic dome. However, this should have been impossible. Simply put, the lava was too full of crystals to move. It would be like trying to make a volcano by erupting crunchy peanut butter. The explanation is clear when you explore the local area a little. A large fracture, or fault, cuts through the landscape next to Picrite Hill. Sometime around 90 million years ago this fault opened up, splitting apart the seafloor and allowing crystal-rich sludge to squeeze out. A very unusual process, and a fun little exercise and discussion with the class.
And then someone asks a tricky question: Does this process explain how volcanoes form in other places on Earth, or on other planets? That really got us thinking, and the discussion we had ultimately resulted in a paper I’ve just published. The unusual set of circumstances which formed Picrite Hill are probably not that unusual on other planets, and what we observe near Marki might explain a puzzling type of volcano found on Venus.
Venus is a volcanic planet whose surface is hot enough to melt lead. This means that lava which erupts onto the surface flows long distances, forming flat plains rather than steep volcanoes. Except sometimes it doesn’t, and dotted over the surface of Venus are strange, steep-sided volcanoes affectionately known as ‘pancake domes’. How they formed, and what they represent, has been debated by planetary scientists since these domes were discovered in the 1980s. What we see at Marki looks like a miniature version of this, with a steep volcanic dome sitting on a flat, volcanic plain.
Does Picrite Hill provide an explanation of how pancake domes form on Venus? It’s an intriguing idea, and I’m waiting to see what the reviewers of the paper think. What it does demonstrate, however, is how teaching can lead research. A pleasant chat with Geology students in the Cypriot sun last April, while perched on a small lumpy hill, might have answered a question planetary scientists have been pondering for decades. It certainly reminded me why teaching is so rewarding.
Bromiley, G.C, & Law, S. (2019). Eruption of crystal mush and the formation of steep-sided volcanic domes on Venus: Insight from picritic bodies near Marki, Cyprus. Icarus, https://doi.org/10.1016/j.icarus.2019.113467.