Time lapse virtual and earthquake source seismic imagery at Krafla

This dataset presents seismic recordings from the 2022 Krafla field campaign in NE Iceland, conducted under the IMPROVE project (https://www.improve-etn.eu/). From June 17 to July 26, 2022, a network of 114 seismometers was deployed within the Krafla caldera to investigate the magmatic and geothermal system surrounding the IDDP-01 borehole. This site gained international recognition in 2009 when drilling operations unexpectedly encountered rhyolitic magma at a depth of 2.1km. Ongoing drilling at Krafla is managed by Landsvirkjun, and persistent local seismicity is monitored by a permanent network operated by ISOR. The primary deployment of the temporary network consisted of 104 SmartSolo 5Hz nodes, sampling at 250 Hz, arranged in a reflection configuration of two linear profiles with 30m station intervals centered on the IDDP-01 borehole. The shorter profile (~1km, striking NW-SE) comprised 33 stations, while the longer profile (~2km, striking NE-SW) comprised 71 stations. The northernmost 14 stations on the short profile and the northernmost 21 stations on the long profile recorded 3-component (3C) data, while the remaining stations recorded only the vertical (Z) component. Additionally, the network featured a circular array of ten 3C short-period seismometers (1Hz) with a 150m aperture, recording at 200 Hz. After a few days of recording, four stations were removed from the southern end of L2 and redeployed at selected locations outside the profiles and array (LAVA, ENDL2, INJEC, MOUNT). Originally collected for high-resolution passive reflection seismic imaging of the magmatic system, the raw data are provided in MiniSEED format and are made publicly available to support further geophysical and volcanological research. Waveform data is available from the GEOFON data centre, under network code 11.