How my undergraduate degree in Geology prepared me for working in Geothermal Energy

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Having worked as a lecturer for a few years now, I have noticed that many undergraduate geoscientists struggle to understand how what they are learning, and the skills they are developing, will be useful in the sectors that employ trained geologists.

I know I certainly struggled with this as an undergraduate. I can recall attending a careers day, excited about finding out what the geology job market had in store, only to listen to a career guidance staff member tell us for an hour how our science skills would be great for working in banking and other non-geology jobs. As someone who had specifically wanted to be a geologist since I was sixteen years old, I really struggled with this. Finding out information on what industry jobs were out there, and how to break into those jobs, was really difficult to come across.

With geothermal energy starting to rapidly grow internationally, I thought it might be useful to share how the skills I picked up in my undergraduate degree were really useful as I was developing my career in geothermal.

Mineralogy

Knowing how to identify different minerals in both hand specimen and under a microscope was pretty much the first undergraduate skill I used when I starting out in geothermal. One of the first jobs I had was to describe trays of drill cuttings (called mudlogging in the industry) and make notes about how the minerals were changing at each depth interval of drilling. This was important, because the drillers needed to know when the rocks changed from one type (a lava, for example) to another (such as a volcanic ash deposit). They were then able to adjust their drilling plans and see how well their drilling forecasts were going.

On top of that, I needed to be able to distinguish between the minerals in the original rock and what are called alteration minerals. This is useful because different geothermal alteration minerals are used to understand how the temperature and chemistry of fluids change with depth in a geothermal reservoir.

View of the Wairakei Geothermal Field in New Zealand showing well heads and pipelines that send geothermal fluids and steam to the nearby power station to generate electricity.

Structural Geology

Yes, stereonets* ended up being really useful after all! Cracks in rock, called fractures, control how fluid is circulated in many geothermal systems, so being able to understand how to study the orientation of fractures became a huge part of my geothermal career, especially when it came to using tools that could take oriented images of the inside of a geothermal well.

Being able to analyse structural data patterns and understand what those patterns might tell us about larger scale structures, faulting, and fluid flow turned out to be a really useful topic to have learned about in my undergraduate. Not only that but suddenly all the maths and physics that related to structure and how it interacts with stress started to show its uses, helping me figure out how active tectonics were important to the development of a geothermal field and how its control on geothermal fluid flow.

Igneous Geology and Volcanology

These two are a little specific to geothermal resources developed in igneous regions… but don’t forget, we can make use of sedimentary and metamorphic rocks for geothermal energy as well.

When I started in geothermal in New Zealand, it was mostly about the igneous rocks. I had to seriously dust off some old lecture notes from my undergraduate for this one because I had not really thought about igneous rocks and volcanic processes for about four years. It was interesting to be re-educated in these subjects through the filter of a geothermal lens. Learning again what welded and non-welded ignimbrites were (the deposits of very hot and very deadly pyroclastic flows) and how that was important to how geothermal fluids can be transported through them or stored within them was eye-opening to me! Connecting types of volcanic materials and processes to whether or not they would make a good geothermal reservoir made me realise how what I had studied (and partially forgotten) in my undergrad degree was useful in a way I had not appreciated.

Me exploring lava tunnels in Iceland and trying to explain igneous geology to my non-geologist husband.

Geophysics

This was THE gap in my geology education! I had taken literally no geophysics during my entire university career, undergraduate or postgraduate. Geophysics is incredibly useful for resource exploration and characterisation. This is one branch of geology I wish I had taken more classes on, as I found myself having to pick up a lot of basic information quite quickly. Whether it was understanding what geothermal wireline logs were telling me about subsurface geology, or working alongside seismologists, I found having a basic understanding of geophysical techniques made my work more insightful and my contributions to the overall geology of these energy systems more useful.

Now after years of working on wireline logging in geothermal systems, and alongside amazing geophysicists, I like to think of myself as a hybrid geologist, one capable of identifying a rock type AND understanding how it looks in a geophysical data set. Turns out that geophysics is a fun, and practical skill combo to have in your toolkit.

Geochemistry

Whether you learn geochemistry as its own subject, or you pick it up through other modules like metamorphic petrology, geochronology, or isotope geochemistry for example, it has an important role in geothermal energy. Being able to develop techniques that allow you to measure and interpret variations in water, gas and isotope chemistry of geothermal systems is important to geothermal exploration.

Geochemistry is important when trying to understand how temperatures and fluids change with time in our geothermal resources. Being able to chemically identify what fluids are in your geothermal system helps us understand how fluids are circulating within the Earth’s crust. Knowing the fluid compositions of a geothermal system is crucial for well planning, so well engineers can account for pipe corrosion risks from acidic fluids for example. So, if you are more chemistry inclined there is definitely a role for you in the geothermal industry.

Field Mapping

There are so many skills that you develop during your field mapping training in your undergraduate degree. I have to say, the one I have used least is the one I spent most time developing – how to map out geological boundaries in the field! Not that this skill is useless in geothermal geology, far from it, but most of the fieldwork I ended up doing as a geothermal geologist was smaller scale, like performing detailed outcrop studies. I also realised I needed to develop new mapping and field skills, like how to collect data in an organised and statistically useful manner, or what it is like to mark up and map a fault trench. Each of these new skills used some version or aspect of the undergrad field skills I had learned; measuring orientations, creating lithological logs, describing the rocks, etc. – but it made me realise that my undergraduate perception of field mapping and what geologists use it for was very limited, and that there is a whole world of field geology out there with some really interesting applied purposes.

One undergrad field skill that was definitely used over and over as a working geologist was how to take my field data (no matter what scale I had collected it at) and put it in context of the bigger geological picture and geological history. That is one of the most important and interesting aspects of my fieldwork, that began in my first year of university and has continued with me to this day.

Marking and mapping a trench dug across a fault line in a geothermal field to investigate its character and understand how frequently active it is. This lets us assess its risk to local power plant infrastructure.

Professional Skills

Finally, I have to talk about professional skills. Giving presentations and writing reports – some of the more dreaded phrases and words I experienced during my own undergraduate. Looking back and knowing what I know now about working as a geologist, researcher and consultant, I wish I had done more of this in my undergraduate. In fact, I wish I had practised these so much that my lecturers started to dread asking me to do it!

Working in industry you are always presenting your data to someone; drillers, engineers, managers, project leads, head-geologists, business and financial managers, and even company chief executives. Developing your communication skills (visual and otherwise) and working on your confidence and presence as a speaker are really important, because you do it so much as a geology professional. Writing reports is also insanely important as an industry geoscientist. Being able to explain your work on page through text and diagrams and graphs, and doing it succinctly and understandably to a range of energy sector professionals (scientific and otherwise) is what will keep you getting work over and over again. Any training your get in these professional skills in your undergraduate are golden opportunities not to be avoided, because there you can practise them with pretty low stakes. This will help you be more ready to do this in the higher stakes industry setting, where your presentation is key to landing you a consultancy job, or your report will serve as the basis for a company to make a big bucks decision. 

Bridging the gap between degree and industry

There are many other skills and geo disciplines that could be turned to use in geothermal, and I guess that is really the point I will end on here. My advice to undergraduate geologists who want to get into geothermal, or any other industry role really, is to focus on the skills you are learning in your modules and classes and get comfortable using them. The module titles themselves are not as important, but the skills you learn within those modules are what employers want to know about. Flesh out that CV with your ability to use stereonets, to work with GIS software, to perform detailed outcrop analysis and data collection, to describe and identify minerals, to process and interpret wireline logs, etc. and then say how you think you can adapt those skills to the role you are going for.

You will start to realise quickly that you can find ways to use any of your undergraduate skills in many different geology jobs. When I realised this, I took my skills from geothermal to carbon capture and storage, started looking at mineral deposits, and even began working in earthquake hazard geology too. It was the same set of skills, just tweaked a little here and there to suit what I was trying to do.

With the growing demand for greener energy, geothermal is quickly becoming a focus for many countries. That’s gonna need more geologists with the geology and geophysics skills needed to help make those geothermal energy strategies a reality, Hopefully, my thoughts on this help give you an idea of what skills you can work on that will be useful to making a career for yourself in geothermal, and help your realise that the same skills can be used elsewhere too.

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Geothermal Jargon!

Geothermal Field – an area (km²) that holds potential to produce energy.

Geothermal Reservoir – a subsurface volume of rock that contains geothermal fluids that can be tapped into with a well to produce energy.

Geothermal well – a well drilled into a geothermal resource to either extract geothermal fluids for energy production, or inject fluids into the subsurface to become heated.

Geothermal Fluids – high temperature, sometimes high pressure, mixture of fluids and gas that circulate in the subsurface that can be tapped with a well to generate energy.

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*Editor’s note- Stereonets are a circular plot used to display the orientation of geological structures like faults and fractures. They are a bit fiddly to use , most geology students aren’t big fans!!