RELATIONSHIP BETWEEN EFFUSION RATES, FLOW EMPLACEMENT STYLES, AND SPATTER DEPOSITS OF THE 2021 FAGRADALSFJALL ERUPTION

The Fagradalsfjall volcano began to erupt in the late evening of March 19, 2021 (Patel & Dauphin, 2021). The Fagradalsfjall volcano is located on Iceland’s Reykjanes peninsula, 40km southwest of the country’s capital Reykjavik and continues to erupt as of the date of this abstract submission (July 20th). This eruption has been recorded and live streamed by the Icelandic news outlet, RUV since March 20, 2021. Using the recorded and live streamed video footage from March 20, 2021, at 12:00pm to March 25, 2021, at 23:59pm (Stebbigu, 2021), I investigate the connection between three components of the eruption: effusion rate, flow emplacement style, and the magnitude of spatter deposition. I aim to answer two questions, first of which is how does the effusion rate relate to the style of flow emplacement? Because emplacement style dictates the speed of advancement of a flow front, a robust relationship between effusion rate and emplacement style could improve flow forecast run out time. I qualitatively ranked effusion rates one through five, with one being ~20% of the lava field being active and five being ~80%. I also identified four main flow emplacement styles: resurfacing, marginal breakout, inflation, and tube. Resurfacing flow is identified when a there is new lava flowing on top of a previous flow. Marginal breakout is identified when the flow is occurring at the edge of the lava field. Inflation flow is when the crust is not moving laterally but is moving vertically. Tube flow consists of crusted over channelized regions that continue to transport lava. Initial research leads me to believe that when there is a change in effusion rate there is also a change in flow type. My second question is if there is a connection between the effusion rate and the frequency of spatter deposits. When looking at spatter deposits I will be recording the vent that originated the spatter and the duration of spatter deposition. I will also be using the same five categories of effusion rate as previously stated. These timelines will allow me to determine any relationships graphically and qualitatively between the effusion rate, style of flow, and the frequency of spatter deposits which may help eruption forecasting based on vent behavior in the future.