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The evaluation of viewpoint geosites is a recent topic in geosciences, as most works deal with a more general analysis of places and areas, but this one deals with something more specific. Therefore, the general objective of this paper is to propose a method for evaluating viewpoints, based on the assumption that it is necessary to use scientific and aesthetic values as core values in quantitative evaluation. The method used was built based on criteria from other authors, relating the issue of viewpoints to geodiversity, considering scientific and aesthetic values as central, but in addition to other values. With the application of this method at some viewpoints in Rio Grande do Norte, Brazil, it was possible to verify that from 12 sites, 9 were considered geomorphosites and only 3 geodiversity sites. Consequently, this method shows a significant response in highlighting the potential of a site, its geological composition, geomorphology, and landscape visualisation. [ABSTRACT FROM AUTHOR]

This paper presents the geomorphological features of four areas of subtropical, southernmost Brazil displaying striking landforms developed upon Precambrian Camaquã Basin conglomerates in the southern Brazilian shield areas. The distinctive and unique features of the Serra do Segredo cuesta, the Rincão do Inferno canyon, the Casa de Pedra inselberg, and the Pedra da Cruz cap-shaped hills are important examples of such conglomerate geomorphology in South America and in Brazil, where few occurrences were available so far. They are the first documented conglomerate landforms in southernmost Brazil, widening the distribution of such terrains in South America and in the subtropical, southern hemisphere areas, considering recent global reviews. Besides the high scientific relevance for geomorphology as a whole, such features are important also for (1) evidencing the decisive role of lithology, structure, and water flows in the formation of such landforms; as well as (2) ecology and tourism, being distributed within and in the vicinity of the Caçapava UNESCO Global Geopark of southernmost Brazil. • Novel description of conglomerate geomorphology developed upon Ediacaran alluvial/fluvial deposits of the Camaquã Basin in subtropical, southernmost Brazil. • Different landforms developed according to bed tilting and arrangement, as well as to tectonic structures "pre-design". • Decisive role of lithology and water in shaping ranges and hills. • Contribution to a global distribution of conglomerate landforms, especially in humid, subtropical areas. • Geological heritage potential, features within and in the surroundings of the Caçapava UNESCO Global Geopark. [ABSTRACT FROM AUTHOR]

Geomorphological studies are crucial for understanding the evolution of relief, and when associated with cartography, they enhance the interpretation and knowledge of environmental dynamics. Hence, historical cartography is essential for the documental rescue of landscapes, which, based on the mapped geoforms, enhances post-discovery studies for the state of Ceará, Brazil. Historically, this state was intermittently mapped in the sixteenth and seventeenth centuries but gained greater attention from Portugal in the eighteenth and nineteenth centuries after its separation from Pernambuco. Despite this, cartographic studies on coastal geoforms are not typical for the Ceará coast over a given period, highlighting the importance of this investigation. Therefore, this article aimed to study the environmental history of the coastal geoforms mapped on the extreme west coast of Ceará in the seventeenth and eighteenth centuries. This research had a qualitative and exploratory basis, with cartographic documental surveys online and in loco, covering the municipalities of Jijoca de Jericoacoara, Camocim, and Barroquinha. Fifty maps of different origins were collected, three of which were used: a French sketch and two Portuguese maps. In the French material of 1615, geoforms in the Cape de la Tortue indicated the presence of a rocky island separated from the mainland. From the Portuguese map of 1629, a well-cut coastline was noted, identifying Buraco das Tartarugas, where there were two islands of different sizes. In the 1794 map, an island in the cove called Geri qua Coá was noted, differing in landscape from the previous ones, as it did not have tombolos connected to the continent. The cartographies presented particularities for revealing a possible advance in the local sea level. Thus, it is possible to motivate future research in the area of historical cartography as a tool for the analysis of the paleogeographic evolution of the coastal zones of Ceará. [ABSTRACT FROM AUTHOR]

Pastures occupy a large part of Brazilian national territory, being of heterogeneous characteristics and varying in climate, fertility, and management. Water erosion, generated by the action of rainfall, is a principal source of soil depletion. These soils exhibit distinct behaviors spatially and temporally. Therefore, this research aims to evaluate the water and soil losses in a pasture of the Cerrado region during two periods of the year (winter and summer) with the aim of understanding the hydro-geomorphological dynamic of the pastures in question. A rainfall simulator was calibrated at 64.34 mm/h, to replicate similar intensities to those of the study region, for 30 minutes (32.17 mm) over four erosion plots. Overall, the plots presented low water and sediment losses, with the largest runoff volumes in the summer and the highest erosion rates in winter. These results are connected to seasonal climate variations expressed in the region, which are reflected in the plant growth habits, generating alterations in the structural quality of the pastures. It follows that the return of the rainy season (winter-summer transition) represents a critical phase for the triggering of the erosive process. [ABSTRACT FROM AUTHOR]

In the last decade, detailed geomorphological analyses of northeast Brazil led the authors to publish a model of landscape development in which long-term landform evolution was driven by regional swell-like uplift post-dating Early Cretaceous intracontinental rifting and the formation of the Atlantic passive margin in Aptian times. The post-Cenomanian uplift caused an inversion of Cretaceous basins and generated a landscape in which the most elevated landforms correspond either to resistant post-rift sedimentary cover, or to residuals of Cretaceous rift shoulders, above a low erosion surface. Since no evidence of a former post-Cenomanian sedimentary cover of significant thickness was found outside the coastal fringe, we could evaluate the uplift to 600 m at most and the mean erosion rates to 10 m/Ma or less. However, according to models based upon the results of thermochronological analyses (apatite fission tracks analysis-AFTA), two slices of 1000 m to 2500 m would have been deposited over the present pile in the south part of the study area, respectively in Campanian and Oligocene-Miocene times, before being totally removed. We examine here the diverging scenarios of geomorphic evolution respectively based upon morphostratigraphy (our model) and upon low temperature thermochronology, submitting them to available evidence provided by an updated and geographically extended review of geomorphological and sedimentological data, and trying to decipher some of the reasons that might lead to disputable geomorphic interpretations. We stress the fundamental importance of taking into account all the available results of geomorphological and geological approaches in any interpretation of thermochronological and other analytic methods used for reconstructing long-term landscape evolutions. This is one of the conditions for reinforcing the trust one can have in their results, which may bring complementary or unique information, peculiarly in places where sedimentary or volcanic markers are missing. • A model of landscape evolution in NE Brazil is proposed based on morphostratigraphy. • Thermochronological studies suggest another scenario of regional landform evolution. • This review paper aims to explain the discrepancies between both types of scenarios. • Recent geological data confirm the general overestimation of denudation by AFTA. • Morphostratigraphic constraints are fundamental to interpret AFT primary results. [ABSTRACT FROM AUTHOR]