Coastal Cliffs of the Rio Grande do Norte State: Geoheritage Characterization and Valorization in Northeast Brazil

Abstract

The Rio Grande do Norte state, Northeast Brazil, has 410 km of coastal extension, being 107 km approximately composed of cliffs excavated in Cenozoic sedimentary rocks. In the last three decades, these cliffs are passing for transformations due the human occupation, tourism activity and climatic changes. To inventory the geoheritage present in these cliffs is essential to support management plans that include investment to conserving part of this Earth’s natural history. This paper aims to inventory, classify, assess and value the Potiguar cliffs as geological sites. From 46 outcrops that Saraiva Junior (2021) studied to describe the cliffs’ geomorphology, 20 geological sites were selected, these are used in national and international publications and divided in three frameworks: Miocene-Pliocene sedimentation, Pleistocene sedimentation and Cenozoic tectonics. These 20 cliffs were inventoried using the Brilha (2016) methodology in order to qualify and quantify the scientific value, potential educational and touristic uses and degradation risk. The Ponta do Mel, Barra de Tabatinga, Ponta dos Três Irmãos, Barreira do Inferno, Ponta do Reduto and Morro do Chapéu were defined as the most valuable cliffs on the scientific aspect. We proposed monitoring planning based on the cliff’s baselines, protection measures based on the specific threats and three geotouristic routes based on the geographic distribution of the sites and the frameworks.