Seismo-meteorological monitoring of an earthquake swarm

The important role of fluids in the rupture or initiation process of earthquakes is undisputed. Yet, the particular mechanisms through witch fluids and associated parameters influence the stress regime and seismicity of particular area are not well understood. Here we introduce a new study of the spatiotemporal behavior of earthquakes, fluid-related parameters (ground water level) and meteorological observables (precip-itation, atmospheric pressure) carried out in the swarm quake area of Bad Reichenhall (SE-Germany). The goal of this study is to find an answer whether rainfall, ground water level, atmospheric pressure (gradients) and/or overburden pressure are causally related to the observed seismicity pattern in space and time. In early August 2002 intense rainfall produced a precipitation of 130 l/m2 in 48 hours in Chiemgau and Berchtesgadner Land. This nearly is the monthly average for this region calculated for a reverence time window from 1960 to 1991 by the German Meteorological Service. The beginning of an earthquake swarm fell together with this intense rain event. The swarm reached its maximum 10 days later. Seismicity remained on a raised level until end of November. Over 600 micro-earthquakes where recorded during this time span. The strongest events reached magnitudes of around ml =2. A minor intense rain event in March 2002 was also followed by an earthquake swarm. These observations support the assumption that meteorological parameters influence the seismic activity of the Bad Reichenhall area. A seismo-meteorological monitoring network was installed in the Bad Reichenhall area in 2002. It consisted of 8 seismological stations, 4 rain gauges and several groundwater wells, all very close to the source region. Data of this network and first results of an interpretation of the spatio-temporal distribution of hypocenter with a pore pressure diffusion model will be shown in the presentation.

@inproceedings{id632,
  address = {Nice, France},
  author = {Kraft, T. and Schmedes, E.  and Igel, H.},
  booktitle = {EGU, 1st General Assembly},
  language = {en},
  title = {Seismo-meteorological monitoring of an earthquake swarm},
  volume = {EGU04-A-04410},
  year = {2004},
}

%O Conference Proceedings
%C Nice, France
%A Kraft, T.
%A Schmedes, E. 
%A Igel, H.
%B EGU, 1st General Assembly
%G en
%T Seismo-meteorological monitoring of an earthquake swarm
%V EGU04-A-04410
%D 2004