Geo-physical study

Several geo-physical studies have been run on the test bed to determine the thickness of the layer of unconsolidated sediments (sands, muds, etc.). This information is essential to design the kind of anchoring systems for any prototypes to be installed on the test bed (wind turbines, wave converters, etc.).

Studies of this kind can use direct methods (corers that penetrate the sea bed until they reach the lower limit of the layer) and indirect methods, using echo-sounders that emit acoustic pulses that penetrate the sea bed and the return signal is analysed.

Two studies have been carried out using indirect methods to date, and several using direct sounding methods (the latter are described in the section on geo-technical studies). The first geo-physical study was carried out in October 2012, in a specific zone of the test bed, aimed at identifying the best areas for locating the PLOCAN multi-use platform, at a range of depths between approximately 20m and 30m. The instrumentation used in this case was a Boomer (a small catamaran towed by a boat).

The second study was conducted in April 2013, to analyse a larger area of the test bed, encompassing a depth range of 20-200m. This study was done with a TOPAS PS18 sub-bottom profiler.

The results of these studies are shown in the following graphs, which show that there are areas with potentially up to 15 metres of unconsolidated sediment (mainly sand).