An international drilling expedition off the Norwegian coast led by Christian Berndt, Professor of Marine Geophysics at GEOMAR Helmholtz Centre for Ocean Research in Kiel, and Sverre Planke, Professor of Marine Geophysics at the University of Oslo, confirms the theory that methane emissions from hydrothermal vents were responsible for global warming about 55 million years ago. The study, published today in the journal Nature Geoscience, shows that the vents were active in very shallow water depth or even above sea level, which would have allowed much larger amounts of methane to enter the atmosphere.
About 55 million years ago, the Atlantic Ocean was born. Until then, Europe and America were connected. As the continents began to move apart, the Earth’s crust between them ruptured, releasing large volumes of magma. This rift volcanism has led to the formation of large igneous provinces (LIPs) in several places around the world. One such LIP was formed between Greenland and Europe and now lies several kilometres below the ocean surface. An international drilling campaign led by Christian Berndt, Professor of Marine Geophysics at GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany, and Sverre Planke, Professor of Marine Geophysics at the University of Oslo, Norway, has collected extensive sample material from the LIP, which has now been evaluated.
In their study, published today in the journal Nature Geoscience, the researchers can show that hydrothermal vents were active at very shallow depths or even above sea level, which would have allowed much larger quantities of greenhouse gases to enter the atmosphere than previously thought.
Read more at Helmholtz Centre for Ocean Research Kiel (GEOMAR)
Image: A drill core is brought on board the JOIDES Resolution for scientific analysis. Photo: Sandra Herrmann (IODP/JRSO)