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Abstract

The dataset is supplementary material to the Solid Earth research article of Leonhardt et al. (2021). The dataset is a high-resolution catalog of seismicity framing the stimulation campaign of a 6.1 km deep Enhanced Geothermal System (EGS) in Helsinki suburban area, Finland. Within the St1 Deep Heat project, a total of 18,160 m3 of fresh water was injected into crystalline rocks during 49 days in summer 2018. The seismicity was monitored by a 12-level seismometer array at >2km depth and a seismic network of near-surface borehole sensors surrounding the EGS site. We expanded and refined the original catalog of Kwiatek et al. (2019) including detected seismic events and earthquakes that occurred two month after the end of injection and determining new locations and relocations on the basis of a new velocity model derived from a post-stimulation vertical seismic profiling campaign. A detailed description of the catalog reprocessing as well as a description of basic statistical and spatio-temporal properties of the catalog can be find in the data description file. Definition of columns in the data table (also in the header of the data): event ID, event class, datenumber [integer part = day since year 0], year, month, day, hour, minute, seconds, local magnitude MLHEL, moment magnitude MW, absolute location in local cartesian coordinates [easting (m), northing (m), altitude (m)], relocated location in local cartesian coordinates [easting (m), northing (m), altitude (m)], fault plane solutions of estimated focal mechnisms [strike (°), dip (°), rake(°)] and root mean square fault plane uncertainty of estimated focal mechanisms.