Modelling injection induced seismicity in the Hengill geothermal field
- 1Swiss Seismological Service, ETH Zürich, Zürich, Switzerland (antoniopio.rinaldi@sed.ethz.ch, vanille.ritz@sed.ethz.ch, snandan@ethz.ch, stefan.wiemer@sed.ethz.ch)
- 2Geo-Energie Suisse AG, Zürich, Switzerland (r.castilla@geo-energie.ch, d.karvounis@geo-energie.ch)
The Hellisheiði Geothermal Field is situated in Southwest Iceland and composes the Southern part of the Hengill Volcanic System. This area is characterized by a complex triple junction between three tectonic features: the Reykanes Peninsula rifting, South Iceland Volcanic Zone and West Volcanic Zone. Reinjection of spent geothermal fluids is distributed mostly in two areas (Gráuhnúkar and Húsmúli), comprising respectively 6 and 5 active injection wells. The Húsmúli reinjection area, commissioned in September 2011 and has seen significant seismicity associated with drilling and injection operations.
In the framework of the Geothermica project COSEISMIQ (http://www.coseismiq.ethz.ch/en/home/), a dense temporary network was installed to monitor the seismicity in the Hengill region between December 2018 and August 2021. With this enhanced network, novel analysis and relocation techniques, a high resolution relocated catalogue was curated and comprises over 3600 events in the Húsmúli area.
We use numerical models, some purely statistical (ETAS and Seismogenic index) and a hybrid model (TOUGH2-Seed) to reproduce observed seismicity in the Húsmúli reinjection area during the COSEISMIQ project. We employ a pseudo-forecasting approach and compare models performances
and fit to the recorded data.
How to cite: Rinaldi, A. P., Ritz, V., Nandan, S., Castilla, R., Karvounis, D., and Wiemer, S.: Modelling injection induced seismicity in the Hengill geothermal field, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10392, https://doi.org/10.5194/egusphere-egu22-10392, 2022.
