Erosion of areas of oil and gas exploration along the coast of northeastern Brazil: the Guamare hotspot

摘要

Guamare is one of the coastal erosion hotspots along the Brazilian coast. This area is subject to alternating erosive and depositional processes. It has extensive longshore drift to West North-West, which promotes spit growth and changes the hydrodynamic processes on the coastline. Guamare is an important area, where, since the 1980s, a series of oil and gas pipelines have been installed on Minhoto beach. Because this is a critical coastal erosion area, nowadays the pipelines are evident on the beach, although they were originally installed at a depth of 1.5 m. A comprehensive shoreline evaluation on areas experiencing critical erosion is important for responsible hydrocarbon exploration and development. This paper describes the composition and morphological characteristics of the inner shelf adjacent to the Guamare coastal erosion hotspot. The combination of high-resolution marine seismic, satellite images, geoprocessing and bottom sediment sampling allowed the morphology correlation in the subsurface. The recognition of the pipelines' location on the bathymetric and sonographic profiles, as well as the determination of depositional and erosive areas associated with them, show the importance of this study to the environmental monitoring of submarine areas.