Seafloor morphology and coastal erosion assessment using multibeam bathymetric analysis

This work presents a temporal analysis of the bathymetry of the seabed adjacent to the Ponta Negra beach, located in Natal-RN, Brazilian Equatorial Margim. The system used was the echo sounder Reson/seabat 8124 operated at a frequency of 200 kHz. Two surveys were conducted, the first one in December 2011 and the second one in August 2014. In each survey were collected 50 lines parallel to the coastline, and the spacing between them was 25m, with a total area of approximately 3 km2. The data were processed using the software hypack 2014. The maximum depth found in 2011 was 11.1 and the maximum depth found in 2014 was 12.5 m. A comparison between surveys revealed that the average depth of the study area increased from 9,34m in 2011 to 10.4m in 2014, indicating the strong erosion in this area.