Resumen de Estudio de la dinámica sedimentaria de la plataforma interna gallega: La Lanzada (NO España)
Ruth Durán Gallego, Faustino Manso Galván, Ana M. Bernabeu Tello, Soledad García Gil, Federico Vilas Martín
Sedimentary and bedforms distribution of the inner continental shelf of La Lanzada (NW Spain) was developed based on side scan sonar and echo-sounder data from two different field campaigns.
These results were consistent with data provided by another acoustic technique. Afterwards bottom samples were collected to correlate sound values with sediment type. A characteristic distribution was observed. Bioclastic poorly selected coarse sand, constituting ripples, was located at depths over 20-25 m. Fine moderately well selected sand was placed in the shallower part. These two different fractions were separated by a sharp limit. The ripples have a wavelength from 1 to 1.7 m.
Their crests are sinuous and bifurcated which suggests a wave-induced origin. A detailed hydrodynamical study of the area was carried out to confirm this hypothesis. It was observed that coarser sands are related to higher energies. It was also determined that the sedimentary distribution of the area, in terms of composition and granulometry, is also controlled by the wave conditions and the local bathymetry.
