This RAPID was co-sponsored by the Petrology & Geochemistry program of the Division of Earth Sciences (GEO) and the Europe and Eurasian Program in the Office of International Science and Engineering (OISE).
Starting 20 March and continuing to the present, Eyjafjallajökull central volcano has experienced two different types of eruptions: initial strombolian and hawaiian eruptions of alkaline basalt from the northeastern flank (Fimmvörthuháls), producing lava-snow interactions, and starting 14 April, after a short temporal hiatus, the eruption was renewed beneath the summit caldera of the volcano (Eyjafjallajökull summit). The summit eruption has been much more explosive, and preliminary analyses show that the magma is more silicic in composition. This RAPID is to investigate several important aspects of the eruption during the next twelve months that will results in better knowledge and methodologies for interpreting ancient glaciovolcanic deposits, and also better prepare society for future glaciovolcanic eruptions from Iceland or from western North America.
This is the first documented glaciovolcanic eruption of trachyandesite and alkaline basalt in at least the past two hundred years, and represents a unique opportunity to improve our knowledge of glaciovolcanic eruption processes, which have become critical paleo-climate proxies for linking Pleistocene oceanic and continental climate signals. It is proposed to investigate several important aspects of the eruption during the next twelve months, including (1) textures of lavas now interaction at Fimmvörthuháls, (2) changes in fragmentation processes as documented in stratigraphically constrained samples of ash at proximal and distal locations from the volcano, and (3) changes in magma chemistry during the course of the eruption. In order to obtain the best samples for this work, it is critical to investigate high elevation lava-snow contacts and collect ash samples before deposits are either hydrothermally altered/palagonitized near the vent; reworked by secondary slope transport that will destroy stratigraphic/temporal information; eroded by seasonal rain; or covered by snow/ice during winter 2010-2011. The proposed research will enable the PI and one Dickinson College undergraduate to partner and collaborate with several Icelandic scientists (e.g., Steinunn Hauksdöttir, Birgir Oskarsson) in the pursuit of the research goals.
The goals of this study were to help document and understand the processes driving the eruptions that happened in spring 2010 at Eyjafjallajokull in southern Iceland. This research has at least five important outcomes related to the Intellectual Merit of the grant. (1) Through this research we are our gaining a much clearer understanding of how lava flows can move over snow and ice. Although several older accounts from eruptions in Iceland (Hekla), South America (Hudson), and Kamchatka mentioned lava flows moving or snow or ice, none of the older accounts gave detailed descriptions of what happened during the eruptions, especially how fast the snow/ice melted. This is important to document because lava flows have the ability to melt significant amounts of snow and ice relatively quickly (minutes to hours), which can lead to large scale floods during the course of an eruption. We have conducted experiments making small lava flows and pouring them on to ice at Syracuse University to better understand rates of ice/snow melting (see Image 1). (2) By better documenting how the lava flows looked during and after the eruption, we now have a better idea of how to identify older lava flows that flowed over snow and ice. This allows us to determine where now long-gone glaciers and snowfields existed on high volcanoes, and gives us a better idea of how global climate has changed in the recent past. (3) By looking at the minerals in the lavas and small pieces of rock brought up to the surface in the lava flows, we will also get a better idea of where magma (lava beneath Earth’s surface) is stored beneath volcanoes, and how quickly it can move up to the surface when the volcano becomes active. We have found small inclusions of rocks from older magma chambers beneath Eyjafjallajokull volcano and are working to determine their depth of formation (see Image 2). This information will help us to better understand and interpret the signs of unrest that might indicate a volcano is awakening and getting ready to erupt. (4) We have also used cutting edge computer programs to investigate how much water and carbon dioxide can be contained within magma inside Earth before the magma explodes. Volcanoes that have thick ice on top of them may be less likely to erupt explosively, while volcanoes with thinner ice are more likely to erupt violently; this model will help us to better understand and identify ice-covered volcanoes that are more or less likely to have explosive eruptions. (5) Finally, once a volcano explodes it can send ash across the countryside, burying farms and fields. So, we have investigated the effects of ash mixed with peat moss to determine whether the ash helps or hinders the growth of a typical crop plant (rye; see Image 3). Our preliminary findings suggest that ash maybe actually be beneficial to crops once it is mixed with organic matter, and might be a natural, low cost fertilizer; we are planning more growth experiments to confirm these preliminary results. The Broader Impacts of this study include training three undergraduate students at Dickinson College, introducing two of them to international scientists and collaborators, and assisting in the training of an Icelandic Ph.D. student. Outcome #2 above will also allow scientists who study glaciers to better understand the cycles of ice build-up and retreat because in areas where volcanoes were active, they frequently hold records of ice changes. Outcome #5 has potential to significantly alter people’s view of volcanic ash from being only a nuisance or hazard, to being a potential local and regional economic benefit.
