Search

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. [ABSTRACT FROM AUTHOR]

The Seridó UNESCO Global Geopark is a territory of 2802 km2 located in the interior of the state of Rio Grande do Norte, Brazil, recognized by UNESCO since 2022. The Seridó UNESCO Global Geopark region is located in one of the oldest occupation areas in the interior of Brazil, destined to extensive cattle ranching since the 17th century in semi-arid climatic conditions (average rainfall between 450 and 700 mm per year), being one of the six Desertification Nuclei in Brazil. This article aimed to identify and map the types of land use and land cover in the area. For this, methodological procedures for classifying remote sensing images were applied, based on photointerpretation and manual vectorization techniques, in a geographic information system (GIS). The research classified 11 classes, where anthropized areas stand out (50.63%) that put pressure on most of the 21 geosites; these areas include the classes of degraded vegetation (36.1%), agriculture (5.15%), farming (8.18%), mining (0.34%), urbanized areas (0.6%), and wind farms (0.26%). The conserved natural areas represent (48.15%) of the geopark territory, encompassing facies of shrubby vegetation (30.8%), association of rocky outcrops, colluvium, and shrubby vegetation (6.33%), arboreal vegetation (5%), and apparent riverbed and riparian forest (6.02%). In addition to these classes, there are artificial and natural lakes, with an area of 1.38%. This study was important for the diagnosis of surface cover and land use in geopark in order to discuss alternatives for sustainable economic development, promoting geoconservation, geotourism, and scientific education. [ABSTRACT FROM AUTHOR]

The Earth landscapes were not always as what they present themselves today, thanks to the interaction with the internal and external dynamics of the Earth. Thus, it is clear that the rocks are true “files” where what can informally be called “key files” capable of telling the history of a territory are stored. Threats against outcrop protection demand urgent management actions. Because of it, making an inventory of the geological heritage of a place makes it possible to delimit these places of interest and through a quantitative assessment to support measures for the geoconservation of this natural heritage. The present work consists of the first steps of the elaboration of an inventory of the geological heritage in the state of Rio Grande do Norte (RN), northeast of Brazil, and one of the first state inventories in progress in the country. In this text, it is exposed how the potential geosites were selected based on different bibliographic sources, filtered according to their uniqueness or regional representativeness, to then be organized in a uniform database, with general information about each point for consultation by the scientific community. Cartographic and graphic products were also generated to represent the information obtained in each location of geological interest. This study can be constantly updated and aims to direct future work on the inventory of geological heritage or with emphasis on specific topics such as geomorphological, paleontological, and mineralogical in RN. [ABSTRACT FROM AUTHOR]

Since the end of 2019, two new Brazilian areas are candidates to join UGG/GGN; one of them is Seridó Aspiring UNESCO Geopark, located in the country’s Northeast, state of Rio Grande do Norte. It is named after a native Brazilian word, of tapuia tradition — ceri-toh — which means “little or no foliage; little shade,” something that well defines its landscape, typical of the Caatinga Biome, which is only found in Brazil, and semiarid climate. The local geology comprises eight lithological clusters dating from the Paleoproterozoic to recent. It is a highly diverse territory, whose inventory of geological heritage comprises 21 geosites, with different types of interests, such as mineralogical, petrological (plutonic and volcanic), hydrological, geomorphological, and paleontological, among others, of regional to international relevance. They are integrated with the communities of the region through culture, economy, tourism, and science. Many are recognized by population as a heritage of Seridó. This paper describes all the geosites of the proposed geopark, also analyzing socio-cultural and environmental factors, and hazards related to geological heritage and its surroundings, such as cavities and archeological sites, Caatinga biome conservation, water use, Quilombola and settlement communities, urban proximity, risks in slopes, and especially with regard to the relationship of mining activities in the region, which since the 1940s has boosted the local and regional economy, with the exploitation of scheelite in the Brejuí Mine, the largest mine of its kind in South America, currently one of the geopark’s geosites that has a high scientific value, notably of international relevance. [ABSTRACT FROM AUTHOR]

The Seridó, an interstate region of the northeastern hinterlands of Brazil, which encompasses several municipalities between the states of Rio Grande do Norte and Paraiba, has a geological heritage resultant from a series of natural processes over geological time, with a remarkable petrologic, structural, stratigraphic, and geomorphologic variety. The region is characterized by Paleoproterozoic gneisses, Neoproterozoic metasupracrustal rocks, magmatisms ranging from the Paleoproterozoic to Meso-Cenozoic, and Cenozoic sedimentary rocks. Taking into consideration the uniqueness of this Geological Heritage, it was developed since 2010 a proposal to create the Seridó Geopark, which has been under development and in 2019 the territory was officially accepted as an aspiring geopark. With the geopark proposal also becomes necessary to develop geoconservation strategies. This paper aims to conduct different assessments of 21 geosites of Seridó Aspiring UNESCO Geopark regarding scientific value, educational and touristic uses, and the associated degradation risk. The work is completed with a classification of the types of interest, visualization scale, and relevance of geosites. This work provides solid information, including tables, graphs, maps, and statistic for decision makers to establish priorities for action in order to promote the geosites protection. [ABSTRACT FROM AUTHOR]

The values of geodiversity, defined through different qualitative and/or quantitative methods, represent a fundamental asset for the development of geoconservation actions. Quantitative methods can be considered those of less subjectivity since their dependence on the evaluator and its scientific knowledge is restricted. In turn, aiming to clearly expose the achieved results, this work used geoprocessing tools, as it has been used in several studies of geodiversity index in Brazil. Rio Grande do Norte, a state located in the extreme northeast and one of the smallest of the country, still does not have an assessment for its entire territory, despite being geologically diverse, with rocks dated back from the Archean until the Holocene. Thus, the objective of this work is to fill this gap in the studies of Brazilian geodiversity. For this, we used the evaluation methodology based on the grid overlay, with 5.5 × 5.5 km mesh, on the available cartographic bases: lithology, mineral occurrences, geomorphology, pedology, and hydrography. The thematic subindexes were added, which resulted in the geodiversity index map for the entire state. It was classified into five classes: very low, low, medium, high, and very high. It was verified that most of the state is in low areas in the geodiversity index and that the high and very high areas are concentrated in specific portions, mainly in three distinct regions: Eastern Seridó, Center-East, and Eastern Coast. It was observed that Rio Grande do Norte state is endowed with high potential regions of geodiversity. [ABSTRACT FROM AUTHOR]

Natal is a city located in northeastern Brazil that has a geodiversity composed of different landscapes, flanked by beaches, dunes, cliffs, rivers, mangroves, and lagoons. Throughout the city’s history, which spans more than 400 years, geodiversity has always been present since the early days of local cartography, dating back to the Dutch occupation period, on the seventeenth century, in which the natural environment had been faithfully portrayed. The studies developed in this work approach the geodiversity of Natal City that occurs naturally, in situ. The identification of the main places in which the abiotic nature is highlighted was performed, allied to a geological-geomorphological description. The occurrences were classified according to their area extension and the ecosystem services of abiotic nature, in a system divided into five services (cultural, regulating, provisioning, supporting, and knowledge). In the study area, all services were identified, and of the subclassification in geodiversity goods and processes, 16 out of 25 were observed, which reaffirms the importance of the local abiotic nature. On the tipology of these occurrences, they were identified as sections, areas, point, and viewpoints. Due to its extension and variety, it can be used for science, culture, sports, and tourism, in order to promote, jointly, the dissemination of the natural and cultural beauties of the city and geosciences, helping the geoconservation process. [ABSTRACT FROM AUTHOR]

The evaluation of geodiversity is one of the initial and main steps in the development of geoconservation actions. It is fundamental to establish parameters that quantify elements and places of abiotic nature in order to draw attention to those that are richer than the average. In doing so, it is possible to manage areas for the protection of notable geoheritage and to develop sustainable activities such as geotourism. The literature comprises several methodologies for the quantitative assessment of geodiversity, but the use of geoprocessing tools appears to be the least subjective type of analysis. From this standpoint, this work aimed to analyze the geodiversity in an area of geological interest in the northeast of Brazil by using two methodologies. The first is widely used and involved the definition of a grid to overlay the cartographic datasets that are used to define the geodiversity index. The second method is based on a centroid analysis of intersected datasets. These investigations showed that the two methodologies have similar aspects and produce a high geodiversity index for the area. This outcome supports the reliability of these methods when the results converge, with respect to the delimitation of the valuable places where geodiversity should be protected. These methods may be used as basis for the sustainable management of natural resources. [ABSTRACT FROM AUTHOR]