Seismic Network

Starting in July 2013, four broadband seismic stations equipped with Guralp CMG-6TD sensors were deployed in linear configuration across the main basin-bounding fault in the area (Blackrock-Newcastle Fault, BNF) with an interstation distance of about 1 km. One new station was added in March/April 2014 to extend the array towards SW (DB06). At the same time, due to logistic problems at DB04 site, this station has been re-deployed in a new site (DB05) about 300 m away. All stations have been provided by the School of Earth Sciences at University College Dublin (UCD). Sites have been chosen based on the planned interstation distance, availability of power source and to be as far as possible from noise sources. The sensors come with a built-in digitizer and 3 GB of memory. Traces are recorder at 100 samples per seconds resulting in about two months of autonomy before overwriting. This required a conservative service time of about one month and a half until decommissioning of the array in September 2015. The investigated area is located close to the village of Newcastle and the Greenogue Business Park in an anthropogenic zone. The presence of high rate communications roads and a small aerodrome in the area represent a challenge for the experiment in terms of urban noise, as high frequency RFs are needed to illuminate the subsurface with enough vertical resolution.

Coordinates for the SIM-CRUST seismic stations across the Dublin basin can be found here.

Frequency domain properties of signals recorded at DB01. (a) Mean Amplitude spectra of earthquakes (red) and pre-event noise (blue). Orange and light blue spectra define the total amplitude range for earthquakes and pre-event noise, respectively. (b) Mean (black), minimum and maximum (red lines) SNR.