GEOREAL - GEOthermal experiments in the KTB deep laboratory under REAL conditions of a deep borehole

To seismically monitor the GEOREAL hydraulic stimulation experiment, that took place during the period 6-15 November 2023, a station network was set up in the vicinity of the Kontinentale Tiefbohrung/ KTB deep crustal lab near Windischeschenbach, Germany. The network comprised both surface stations, shallow borehole (25-150 m deep) stations as well as a borehole chain at 2000 m depth in the main borehole, ca. 200m apart from the pilot borehole. First stations were installed in early 2022 and removed in mid-2024. A total of 600 m³ of water was injected into the 4 km deep pilot borehole (KTB-VB, 12° 7.16' E, 49° 48.98' N, 513.418 m above NN ). This volume was injected through a stuck packer in the cased borehole into the open borehole section a depth of 3.85-4 km. No induced seismicity was observed during the injection experiment. Waveform data is available from the GEOFON data centre, under network code 4R, and is fully open.