Greenland is a unique place — not just for having the oldest rocks on Earth, dating back to 3.8 billion years in southwestern Greenland — but because its rocks can potentially be a large deep storage for greenhouse gases. Such gases include methane, carbon dioxide, and hydrogen — all of which are of current interest as a source of renewable energy, and key components for sustaining life on Earth. Identifying the geological processes that produce these compounds is essential for understanding the link between Earth’s biosphere and atmosphere, and thus its role in the emergence of life.
Greenland is not an easy place to carry out fieldwork. Our expedition was set to venture from the capital, Nuuk, located in eastern Greenland, and progress south by boat. Several hours of cruising would take us to the town of Nanortalik or “Place Where the Polar Bears Go”. Admittedly, I was impressed to hear that there was a possibility of encountering polar bears, but the DeepSeep team were set to go and look for evidence of untapped hydrogen storage hosted in rocks, not far from Nanortalik.
Days before our expedition, we learned that we could not access Nanortalik since the shoreline was surrounded by drift ice. Therefore, after our team monitored the drift ice for weeks in conjunction with the captain and guide of our expedition, we ultimately decided to limit the mission to southwestern Greenland – Nuuk, Paamiut, and Arsuk. One evening we had to race against the incoming storm. Charging through the fjords and the last stretch into the open Labrador Sea, we had a small window to return safely to the village of Arsuk. We could see the waves breaking in the windows. It was one of the most frightening but enlightening experiences of my life. You truly realize the skills it takes to live in Greenland and have a new appreciation for the northern seas. It is a way of life.
As geologists, we needed first to find the right rocks, then look inside specific crystals in search for fluids. Different types of microscopic fluids (including gases) can be incorporated into minerals in rocks. These fluid inclusions are a product of certain chemical reactions that we can use to predict or estimate which rocks have the right conditions to preserve gases. Knowing conditions like the type of geologic environment, the pressure and the temperature of when these fluids get generated and trapped in minerals narrows down the type of rocks we geologists are interested in collecting.
Our expedition was focused on metamorphic rocks from the south of Greenland, especially those that contain quartz and graphite (yes, the graphite we use to write with). Quartz is one of the most abundant minerals in Earth’s surface, and, besides being popular for having a wide range of utilities throughout human civilizations, quartz is notorious for containing small inclusions of different fluids, such as water, and gases.
In Greenlandic: “if you fall asleep during storytelling, it means that it was a great story”. So, I hope that I was able to make the reader fall asleep. If not, I hope that I was at least successful in sharing a bit about our expedition to south-west Greenland. Even though our expedition was full of challenging and uncertain moments in which we didn’t know if we were going to be able to continue with the scientific mission, we are happy with the outcome and are confident that we’ve tapped into rocks that also have their own story to tell.
Claudia Roig
Photography by Jacopo Pasotti
(This expedition was supported by Karpos, POC, Polar, and Midland)
