Monitoring and understanding induced seismicity is critical in order to estimate and mitigate seismic risk related to numerous existing and emerging techniques for natural resource exploitation in the shallow-crust. State of the art approaches for guiding decision making, such as traffic light systems, rely heavily on data such as earthquake location and magnitude that are provided to them. In this context we document the monitoring of a deep geothermal energy project in St Gallen, Switzerland. We focus on the issues of earthquake magnitude, ground motion and macroseismic intensity which are important components of the seismic hazard associated to the project. We highlight the problems with attenuation corrections for magnitude estimation and site amplification that were observed when trying to apply practices used for monitoring regional seismicity to a small-scale monitoring network. Relying on the almost constant source-station distance for events in the geothermal 'seismic cloud' we developed a simple procedure, calibrated using several M L > 1.3 events, which allowed the unbiased calculation of M L using only stations of the local monitoring network. The approach determines station specific M L correction terms that account for both the bias of the attenuation correction in the near field and amplification at the site. Since the smallest events (M L < −1) were only observed on a single borehole instrument, a simple relation between the amplitude at the central borehole station of the monitoring network and M L was found. When compared against magnitudes computed over the whole network this single station approach was shown to provide robust estimates (±0.17 units) for the events down to M L = −1. The relation could then be used to estimate the magnitude of even smaller events (M L < −1) only recorded on the central borehole station. Using data from almost 2700 events in Switzerland, we then recalibrated the attenuation correction, extending its range of validity from a minimum source-station distance of 20 km down to 1 km. Based on this we could determine the component of the previously derived station specific M L corrections due to local amplification. We analysed ground-motion and detailed macroseismic reports resulting from the 2013 July 20 St Gallen M L = 3.5 ± 0.1 (M w = 3.3-3.5 ± 0.1) 'main shock' and compared it to a similar M L = 3.4 ± 0.1 event (M w = 3.2 ± 0.1) that occurred in 2006 at another deep geothermal project in Basel, Switzerland. Differences in ground motion amplitudes between the Basel and St Gallen events and to an extent, the associated macroseismic observations, were investigated in terms of the different source terms: M w for long-period motions and the source-corner frequency (related to the source rupture velocity and stress-drop) for short periods.

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this report of the swiss seismological service summarizes the seismic activity in switzerland and surrounding regions during 2008. During this period, 451 earthquakes and 75 quarry blasts were detected and located in the region under consideration. the three strongest events occurred in the Valais, near Lac des toules (M L 3.6), and in Graubünden, near Ilanz (M L 3.7) and Paspels (M L 4.0). Although felt by the population, they were not reported to have caused any damage. However, with a total of only 15 events with M L ≥ 2.5, the seismic activity in the year 2008 was far below the average over the previous 33 years. ZusAmmenfAssunGDieser bericht des schweizerischen erdbebendienstes stellt eine Zusammenfassung der im Vorjahr in der schweiz und umgebung aufgetretenen erd- IntroductionPast earthquake activity in and around switzerland has been documented in an uninterrupted series of annual reports from 1879 until 1963 (Jahresberichte des Schweizerischen Erdbebendienstes). three additional annual reports have been published for the years 1972-1974. these reports together with historical records of earthquakes dating back to the 13th century have been summarized by Pavoni (1977) and provided the basis for the first seismic hazard map of switzerland (sä-gesser & mayer-rosa 1978). With the advent of routine data processing by computer, the wealth of data acquired by the nationwide seismograph network has been regularly documented in bulletins with detailed lists of all recorded events (Monthly Bulletin of the Swiss Seismological Service). since 1996, annual reports summarizing the seismic activity in switzerland and surrounding regions have been published in the present form , 1999, 2001, 2003, 2005Deichmann et al. 1998 Deichmann et al. , 2000aDeichmann et al. , 2002Deichmann et al. , 2004 Deichmann et al. , 2006 Deichmann et al. , 2008. In the course of reassessing the seismic hazard in switzerland, a new uniform earthquake catalog covering both the historical and instrumental periods has been compiled (fäh et al. 2003). the data in the new earthquake catalog of switzerland (ecOs) are available on line (http://www.seismo.ethz.ch, swiss earthquake catalogs). the new seismic hazard map of switzerland based on this catalog was officially released in 2004(Giardini et al. 2004Wiemer et al. 2009). In addition, numerous studies covering different aspects of the recent seismicity of switzerland have been published in the scientific literature (for an overview and additional references see, e.g. Deichmann 1990;Pavoni & roth 1990;rüttener 1995;rüttener at al. 1996;Pavoni et al. 1997;Deichmann et al. 2000b; Kastrup et al. 2004;Kastrup et al. 2007). Data acquisition and analysis Seismic stations in operation during 2008the swiss seismological service operates two separate nationwide seismic networks, a high-gain broad-band seismometer earthquakes in switzerland and surrounding regions during 2008

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