The current Fagradalsfjall eruption within the southwest of Iceland has enthralled the entire world, together with nature lovers and scientists alike.
The eruption was particularly vital because it offered geologists with a singular alternative to review magmas that had been accrued in a deep crustal magma reservoir however in the end derived from the Earth’s mantle (beneath 20 km).
A analysis group from College of Oregon, Uppsala College, College of Iceland, and Deutsches GeoForschungsZentrum (GFZ) took this distinctive alternative to gather lava samples each few days in an effort to assemble a time-integrated catalogue of samples and to observe the geochemical evolution all through the eruption to a level of element not often achieved earlier than.
Normally, when volcano scientists have a look at previous eruptions they work with a restricted view of the erupted supplies – for instance older lava flows can get wholly or partially buried by newer ones. Nonetheless, at Fagradalsfjall, the eruption was so properly monitored and sampled that scientists had an opportunity to seize the evolution of an Icelandic eruption in close to real-time.
The group had been keen on oxygen isotopes. Why? As a result of oxygen makes up about 50% of all volcanic rocks and its isotope ratios are very delicate tracers of mantle and crustal supplies.
On this means, oxygen isotopes might help scientists to find out if magma is mantle-derived or if it interacted with crustal supplies because it made its solution to the floor. Nonetheless, along with oxygen, the opposite huge suite of parts making up the volcanic rocks threw up some surprises. For example, the group noticed that this single eruption incorporates roughly half of the complete range of mantle-derived magmas beforehand recorded for the entire of Iceland.
In short, geochemical outcomes present that the newest Iceland eruption was provided by magmas derived from a number of sources within the Earth’s mantle, every with its personal distinctive elemental traits.
To the amazement of scientists, every of those domains had similar oxygen isotope ratios. This outcome was exceptional and has by no means been noticed earlier than at an energetic eruption. The research gives new and compelling proof for distinct mantle-sourced magmas having uniform oxygen isotope ratios, which might help us to raised perceive mantle dynamics and refine mantle fashions for Iceland.
Header Picture Credit score : Jóna Sigurlína Pálmadóttir