erik sturkell använder en gravimeter

Being a geologist has become a way of life

It is easy to become infected. With enthusiasm. The joy of storytelling. Kindness. To be overwhelmed by such an extensive knowledge of geology. Harder to grasp is all the research projects and playful side projects that Erik Sturkell, a professor of geophysics, has pursued during his 25 years as a researcher.

but let’s take it from the beginning. Born in 1962 and raised in the outskirts of Stockholm first and then in Katrineholm, where the family moved when Sturkell’s father became chief judge in his childhood town. The father hoped that his son would become a lawyer, but Erik Sturkell was more interested in technology and wanted to go his own way. One of the annual family visits in Orsa during Easter proved to be decisive. Among the dinner guests was a professor of geology (from Gothenburg) and Sturkell, who was in his late teens, became interested in the subject.
“So actually geology became my field purely by chance. But I have always been interested in science.”

then came several semesters of geology at Stockholm University, eventually a degree and thoughts about taking a doctorate in marine geology in the Baltic Sea. But instead Sturkell received a grant to study at the Nordic Vulcanology Institute in Reykjavik. This was in 1991.

“I stayed in Iceland for two years and conducted research on movements of the Earth’s crust, recorded how the continental plates moved, examined structures in the Earth’s crust and made seismic observations using geodetic GPS.”

With several research articles under his belt, Sturkell returned to Stockholm University and a doctoral studentship. Along with his professor and supervisor, he discovered a meteorite crater in Jämtland – the Lockne crater twenty kilometres south of Östersund.

“We discovered a chaotic jumble of rocks with large white limestone lying helter-skelter amid crushed granite. The meteorite struck about 458 million years ago in a 500-metre-deep sea, first creating a crater that was then filled by a gigantic backwash.”

Now the site of the impact is flat, consisting of farmland. Sturkell described the discovery in his doctoral thesis in 1998: “The origin of the marine Lockne impact structure, Jämtland”. In the thesis the meteorite’s impact is humorously rendered in a comic strip by Sturkell, who enjoys drawing.

after completing the thesis, Sturkell returned to Iceland because he had a year remaining in his grant to study there. He stayed not one year, but 10.

“For a geologist and geophysicist, Iceland is a scholarly gold mine! I was actually a pioneer with GPS measurements in Iceland and participated in building the measurement stations there. I learned Icelandic reasonably well, and after a couple of years I bought a flat.”

One day a Danish woman, a geochemist doing a doctoral thesis on Iceland, came to Reykjavik. That was in 2007. “Her name is Gabrielle, and I helped her a little bit in the beginning. Two years later we married.”

The couple has travelled around the world together, touring and visiting geological points of interest. Being a geologist has become a way of life.

meteorite craters are one of Sturkell’s main research fields. He has studied many of them. Not only the one at Lockne in Jämtland or the Chicxulub crater in the Gulf of Mexico. He has measured countless depths of craters, analysed their mineral content and compared different craters. Another line of research is volcanoes, especially Icelandic ones such as Hekla, Askja and Grímsfjall. He has followed Grímsfjall since 1983. Nothing with the slightest connection to geology is foreign to him. Along with Cultural Conservator and Professor Ulrich Lange and Thomas Eliasson at the Geological Survey of Sweden, he is currently working on an excursion guide to facade stones in Gothenburg buildings during the 1790–1944 period. He has taken the photographs himself, of course. Another project he has just completed illustrates how the sea level in Gothenburg has varied through the ages, depending on melting of the ice sheet and land uplift. And so it goes. “Conducting research is fun! It is fortunate we do not know everything because then I would be unemployed,” Sturkell says with a smile.

Is there then no other dream job that can compare with research?

Sturkell becomes silent and ponders for a moment. “Being a chef seems fun! During my 10 years in Iceland, I learned how to cook Swedish food that was not available there. And it is good to be able to cook in the field because then you can keep colleagues going much longer. In addition, if you entertain them with a cocktail before the meal, it doesn’t exactly diminish their desire to work,” says Sturkell with a glint in his eye.

in addition to cooking, film interests him. “When you are travelling with geologists, a question often comes up in discussions: ‘How many geologists appear in films? Are they bad or good?’ So my colleagues and I decided to investigate this in a small project.” It turned out that of 97 British and American films with geologists, geologists were good in 85 per cent of them. In the film survey a stereotypical image of the geologist also emerged. Sturkell takes out a drawing of a man with a shining halo, glasses and a beard. A man with a flannel shirt and big boots, who
likes volcanoes and whisky and is exposed to deadly hazards. Sturkell feels this stereotype fits him quite well.

 

Geological research over time

Then: Natural Philosopher Sigfridus Aronus Forsius, born in the 1560s, was the first person to write about Swedish geology. But the first geologists in Sweden probably were the mining experts in Bergslagen. In the 17th century prospectors looked for ore with a compass by setting a course on a straight line in a north-south direction and walking until they saw deviations in the compass needle. In the 18th century people became interested in questions about land uplift, and during the 19th century great attention was given to primary rocks and complex rock formations in the mountains. In the 20th century tools arrived that permitted electromagnetic measurements.

Now:  Today we have many good analytical methods, and geophysical instrumentationis becoming better and more precise all the time. Measuring instruments employ sophisticated electronics. But the mechanical gravimeter is still being used. This instrument uses a lever and weight to measure the Earth’s local gravitational field. Onsala Observatory has an advanced gravimeter in which a steel sphere with a coil levitates at –265 degrees C.  Everything is superconducting. If gravitation changes, the sphere moves. The current needed to keep the sphere in place measures changes in gravitation.

In the future: Determining positions and movements of the Earth’s crust with GPS is becoming increasingly important, and the technology will be transferred to other planets, such as Mars. Geological research fields will be extended into space. We already have rocks from the Moon and Mars. These have been ejected by large asteroid impacts on these celestial bodies. Gravel from the Moon also can be found on Earth. In the future less geological material will be needed for examinations. It will be possible to carry out analyses at great distances. For example, data from the InSight space probe that landed on Mars in late November 2018 might provide new geological insights.

Erik sturkell

Erik Sturkell

Is: Professor at the Department of Earth Sciences, where he has served since 2009.
Age: 56
Family: Wife Gabrielle and two dogs
Curiosities: Is a popular and frequent guest on Swedish Broadcasting’s morning radio show Morgonpasset i P3.