Time-series InSAR measurement using ICOPS and estimation of along-track surface deformation using MAI during the 2021 eruption of Fagradalsfjall Volcano, Iceland

Wahyu Luqmanul Hakim; Muhammad Fulki Fadhillah; Seulki Lee; Sungjae Park; Won-Kyung Baek; Chang-Ki Hong; Hyun-Cheol Kim; Chang-Wook Lee

doi:10.1038/s41598-024-79128-1

Time-series InSAR measurement using ICOPS and estimation of along-track surface deformation using MAI during the 2021 eruption of Fagradalsfjall Volcano, Iceland

Sci Rep. 2024 Dec 28;14(1):30709. doi: 10.1038/s41598-024-79128-1.

Authors

Wahyu Luqmanul Hakim¹, Muhammad Fulki Fadhillah¹, Seulki Lee¹, Sungjae Park¹, Won-Kyung Baek², Chang-Ki Hong³, Hyun-Cheol Kim⁴, Chang-Wook Lee⁵

Affiliations

¹ Department of Science Education, Kangwon National University, 1 Gangwondaehak-gil, Chuncheon-si, 24341, Gangwon-do, Republic of Korea.
² Korea Ocean Satellite Center, Korea Institute of Ocean Science and Technology, Haeyang-ro, Yeongdo- gu, Busan, 49111, Republic of Korea.
³ Department of Geoinformatics Engineering, Kyungil University, 50 Gamasil-gil, Hayang-eup, Gyeongsan-si, 38428, Gyeongsangbuk-do, Republic of Korea.
⁴ Center of Remote Sensing and GIS, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea. [email protected].
⁵ Department of Science Education, Kangwon National University, 1 Gangwondaehak-gil, Chuncheon-si, 24341, Gangwon-do, Republic of Korea. [email protected].

Abstract

The eruption in Fagradalsfjall Volcano, located in Reykjanes Peninsula, Iceland, from several centuries' dormant states, occurred for the first time on March 19, 2021. Observations of Fagradalsfjall Volcano were conducted in 2021, and the eruption period lasted for six months until 18 September 2021. Six days pair of interferograms were generated from ninety synthetic aperture radar (SAR) data. Thus, the SAR data will be acquired from the Sentinel-1 satellite from January until December 2021. Time-series measurements were conducted using a combination of persistent scatterer (PS) and distributed scatterer (DS) points to produce denser measurement points (MPs) in the study area. The improved combined scatterers interferometry with optimized point scatterers (ICOPS) algorithm is the time-series method that utilizes both PS and DS MPs and optimizes those combined MPs using a deep learning algorithm over different temporal intervals and using a statistical clustering approach to optimize the MPs spatially. Validation was conducted by comparing the ICOPS result with GPS measurement in Reykjavik. The comparison with the GPS measurement was performed to validate the line-of-sight (LOS) deformation from the ICOPS measurement, which resulted in an RMSE value of about 0.58 cm, which is considered a good correlation. Besides the time-series Interferometry SAR (InSAR) measurement, we used the integrated InSAR and multiple aperture interferometry (MAI) methods to estimate both LOS and along-track surface deformation, respectively, during the Fagradalsfjall, Iceland volcanic eruption. A pair of ALOS-2 data was used between 28 February 2021 and 23 May 2021. The result from the MAI method shows a deformation of approximately ± 2 mm in the azimuth direction around Fagradalsfjall Volcano. The deformation around Fagradalsfjall Volcano was suggested to be due to the activity of the magma reservoir beneath the Earth's surface, which was formed by dike intrusion. The analysis of the seismicity in Fagradalsfjall was discussed by visualization of the distribution of earthquakes during the deformation occurrence. Further analysis can be conducted by applying multitrack analysis to find the 3D deformation pattern due to the eruption.