The 74 km long Almanzora-Alías-Garrucha canyon system is one of the most important submarine canyons located in the Palomares continental margin (SW Mediterranean Sea). The canyon head and upper course are constituted by several tributaries such as Almanzora, Garrucha, Cabrera and Alias canyons from N to S. During 3 recent oceanographic cruises, different multibeam echosounder datasets were merged and also an extensive network of parametric profiles was recorded to study the canyon. A total of 1519 nautical miles of parametric profiles (TOPAS and Parasound P-35, penetration < 150 m) were acquired in order to characterize the main morphological features and to map the eco-facies defining the deposits and sedimentary processes along the different canyon domains, included its margins. The parametric profiles have been processed after the deconvolution of the continuous 4 kHz Carrier wave pulse acquired using a source wavelet extracted from the data itself. Processing steps include automatically picking of the seafloor, burst noise removing, time-frequency noise attenuation, spherical divergence correction, butterworth and 2D spatial filtering. Finally, reflection strength (envelope of the signal) has been calculated and time-variant amplitude corrected for displaying and interpretation. Different sedimentary features such as bedforms, mass-movement deposits, erosive surfaces, fluid dynamic features and contourites have been defined. Most of tributaries show a progressive indentation and features observed in the upper courses are related to the erosive processes e.g. a dense network of dendritic gullies and minor scars and falls affecting the canyon walls. The seafloor of the southern margin is highly irregular defining an area that extends from 600 to 2240 mwd affected by a mass flows deposits composite. In contrast, the northern margin presents a set of nested concave-downward scars, with a W-E trend, and lengths of 2 to 8 km

FAUCES Project (CTM2015-65461-C2-1-R/C2-2-R) is acknowledged by the data provided and support for this work

VII International Symposium on Marine Sciences (ISMS 2020), 1-3 July 2020 (Barcelona).-- 1 page