Research fellows 2015 - 2016

Name

Postition

E-mail

Phone

Barbara Keine

NordVulk fellow

barbarak@hi.is

Hera Guðlaugsdóttir

NordVulk fellow

heg1@hi.is

+354 525 4496

Jóhann Gunnarsson Robin

NordVulk fellow

jog13@hi.is

Paavo Nikkola

NordVulk fellow

paavo@hi.is

+354 525 5476

Paavo Nikkola

Background
I am a young Finnish geologist with a background is in economic geology and geochronology. I got my Master’s degree in geology from the University of Helsinki in summer 2014, and my M.Sc. project was an in–situ U–Pb dating focused to the Juomasuo gold deposit, one of the prime gold showings in Eastern Finland. For an unknown reason, the hundreds of hours of sample preparation and the tedious data analysis related to my M.Sc. thesis just enhanced my interests towards geochronology. Partly because of that, during the busiest time of my thesis work, I found myself applying for the Nordvulk fellowship program.

Research project
Currently, as a Nordvulk fellow, I am working in a research project aiming to date Plio–Pleistocene to Pleistocene basaltic lava flows in Reykjanes peninsula and in Greater Reykjavik area. These interglacial lava flows are relatively young and low in potassium, which makes them difficult to date by isotopic dating methods. The plan is to overcome the problem of low K by looking into basaltic melt segregations within the lava flows. Melt segregations are a common feature in pahoehoe lavas, and they are produced by 40–60 % fractional crystallization of the host lavas during the lava emplacement. Because melt segregations are enriched in potassium, properly prepared samples of them could theoretically give high quality ⁴⁰Ar*/³⁹Ar –ages resembling the age of the lava flows. If providing positive outcomes, our method of dating could be applied to reconstruct a complete volcanic history of the area.

I have been fascinated by the paleoclimatic history found in polar ice cores ever since the beginning of my M.Sc. study at the University of Iceland. There I measured and analyzed the stable water isotopes δ18O and δ2H of a shallow ice core from NE-Greenland (NEEM) in collaboration with the Niels Bohr institute of Ice and Climate. I realized during this work that it combined my broad interests in science, partly explaining my B.Sc. background in microbiology and physics.

At NordVulk, I will be studying the atmospheric circulation changes that occur after tropical eruption versus local Icelandic eruption. Such analysis requires General Circulation Model (GCM) outputs but stable water isotopes from Greenland ice cores will also be used in order to detect a climatic fingerprint related to volcanic events. The cause of such events is mainly the volcanic sulfate aerosols that influence the Earth´s radiation budget but various dynamic oceanic and atmospheric forces determine it´s local and/or global effects. I want to see if a difference in the circulation pattern can be observed between tropical and local (Icelandic) eruptions and if that difference is detected in the isotopes. Atmospheric circulation, and thus temperature, can be retrieved from the isotopes, making them an excellent climate proxy.