Hanneke Paulssen*1, Islam Fadel2, Mark van der Meijde2, Wen Zhou1, Arie van wettum1
1Department of Earth Sciences, Utrecht University, The Netherlands (email@example.com), 2Department of Earth System Analysis, University of Twente, Enschede, The Netherlands.
Since 1983, the Network of Autonomously Recording Seismographs (NARS) has been deployed in various regions in Europe, Mexico and Botswana. I will present some of the experiences on deployments and instrumentation, and will focus on recent results from our project in Botswana.
Furthermore, I will present noise interferometry results of geophone data from a deep borehole in the Groningen gas reservoir in the Netherlands. It is shown that the seismic structure of the reservoir at 3 km depth can be accurately determined from anthropogenic noise. Moreover, it may be possible to infer time lapse variations from repetitive sources such as regularly passing trains.
An obvious, but important, message for passive seismic acquisition is that the seismic sources are essential for the research that can be achieved.