Jurandyr Luciano Sanches Ross

The inventory of geological heritage of the state of São Paulo, Brazil: Methodological basis, results and perspectives

An inventory of geological sites based on solid and clear criteria is a first step for any geoconservation strategy. This paper describes the method used in the geoheritage inventory of the State of São Paulo, Brazil, and presents its main results. This inventory developed by the geoscientific community aimed to identify geosites with scientific value in the whole state, using a systematic approach. All 142 geosites representative of 11 geological frameworks were characterised and quantitatively evaluated according to their scientific value and risk of degradation, in order to establish priorities for their future management. An online database of the inventory is under construction, which will be available to be easily consulted and updated by the geoscientific community. All data were made available to the State Geological Institute as the backbone for the implementation of a future state geoconservation strategy.

O contexto geotectônico e a morfogênese da Província Serrana de Mato Grosso

The watershed between the Cuiaba and Paraguai river basins (Parana River hydrogra phical basin) and the Arinos and Teles Pires rivers (Amazon hydrographical basin), is characterized by a large area (aproximately 400km by 40km) of residual relief, remaining from erosive phases of the pre-Cretaceous and the Cenozoic. The relief resulted initially from an orogenic activity that occurred during the Upper Precambrian, starting from a geosynclinal basin and from the generation of the orogenetical belts of the Brazilian Cycle. From this process resulted the extensive Paraguai-Araguaia geosyncline. The residual mountains sustained by sandstone and secondarily by limestone are part of this great geosyncline. The foldings associated to elapsed and inverted faults followed by several erosive phases are responsible for the relief of the best preserved folded structures in Brasil. In this kind of modelling one can specially observe: asymmetric ridges on the borders of internally eroded anticlinals; raised synclinals or, still, abrupt slopes on the sides oflevel led top anticlinals, parallel to synclinal valleys; closed anticlinal depressions; superimposed valleys, water and wind-gaps, flat-topped interfluves at various altimetric levels and also large sorrounding depressions. The genesis of these reliefs can be found not only in the former tectonics that produced the orogenic belt but also in the Cenozoic tectonics that brought them back to salience, with the epeirogenic lifting of the Southamerican Platform and the erosive processes that followed mainly in the Upper Cenozoic

Relief-Rock-Soil relationship in the transition of Atlantic Plateau to Peripheral Depression, Sao Paulo, Brazil

This paper presents an atlas of physical geography at a detailed scale for an area located between two large morphostructural units: the Atlantic Plateau, a crystalline shield of rough landforms, and the Peripheral Depression, a transition unit from Plateau to the Parana Sedimentary Basin, whose smooth landforms are generally sculpted over sedimentary terrain. The transition between these two land systems creates contrasting landforms as a function of bedrock structure and soil type. Smooth landforms underlain by sedimentary rocks and reddish clayey soils alternate with small hills with abrupt slopes sustained by igneous or metamorphic rocks. These soils, developed from weathering of siltstones can rapidly change to brownish and pale colors indicating leaching and weathering of stratified sandstones or massive structured quartzites. A geomorphopedological classification at 1:10,000 scale was performed initially by delimiting units according to landforms. Secondly, other themes were added by combining them with different types of rocks and soils. The geomorphological map was produced by using thematic maps including a topographic base map, hypsometric map, slope map and morphological map. Also the geological and pedological maps were created based on field data collection, morphological analysis of soil profiles and physical, chemical and mineralogical laboratory analysis. Finally, the geomorphopedological units were defined using all the mapped data. Each of these units has peculiar features concerning developed or undeveloped soil formation, with mineralogy and structure very often linked to underlying rock. The landform shape is either controlled by geologic structure or originated from weathering processes that make the relief flatter.

FRAGILIDADE AMBIENTAL URBANA (urban environmental fragility)

A questao ambiental urbana nas cidades brasileiras apresenta um quadro bastante problematico. Referidos problemas sao derivados de um modelo de crescimento que nao considerou as limitacoes impostas aos ambientes de maior fragilidade, desencadeando uma serie de conflitos socioambientais. Devido a pertinencia da tematica, emerge a necessidade do desenvolvimento de estudos ambientais integrados para compreender e dimensionar a problematica ambiental urbana. Busca-se com este artigo demonstrar que a fragilidade ambiental constitui eficiente instrumento de investigacao em ambientes urbanizados, fornecendo subsidios para a implementacao de estrategias e acoes visando a reducao dos problemas socioambientais urbanos. Para tanto, utiliza-se como exemplo de aplicacao dessa metodologia a investigacao da fragilidade ambiental na cidade de Fortaleza-Ce. Palavras-chave: Fragilidade ambiental, Analise ambiental integrada, Ambiente urbano. Abstract The urban environmental issue in Brazilian cities presents a quite problematic picture. Such problems are derived from a growth model that did not consider the limitations imposed on the most fragile environments, triggering a series of socioenvironmental conflicts. Due to the relevance of the subject, the need of the development of integrated environmental studies emerges in order to comprehend and scale the urban environmental problematic issue. This article seeks to show that the environmental fragility constitutes an effective investigative tool in urbanized environments, providing subsidies for implementing strategies and actions to the reduction of urban socioenvironmental issues. Therefore, it is used as an example of application of this methodology the investigation of the environmental fragility in the city of Fortaleza-Ce. Key words: Environmental fragility, Integrated analysis, Urban environment. Resume La question environnementale urbaine dans les villes bresiliennes c’est assez problematique. A cause d’un modele de croissance absolument negligent par rapport a la fragilite de certains milieux, le resultat c’est une gamme de conflits socio-environnementales. Grâce a la pertinence de ce sujet, il faut developper des etudes environnementaux integres afin de souligner sa complexite. Dans ce contexte, on veut signaler l’importance de la notion de fragilite environnementale en ce qui concerne a l’amenagement de milieux urbains. Pour cela, notre etude de cas est la ville de Fortaleza-CE. Mots-Cles: Fragilite Environnementale; Analyse Environnementale Integree; Milieu Urbain

REVISÃO DOS CONHECIMENTOS SOBRE O RELEVO DO PLANALTO ATLÂNTICO BRASILEIRO: INCÓGNITAS QUE AINDA PERSISTEM

This paper attempts to outline the current state o knowledge on the importance of the Brazilian Atlantic Plateau, through an extensive review of the literature on studies conducted since the 1930s to the present day. In this review, it is possible to observe the development of a true school of Brazilian geoscientific thought. Firstly, there is a line of erosive geomorphological models with tectonic implications. Secondly, it is possible to find another strain with morphoclimatic approach based on Quaternary climate change. Thirdly, there is a sequence of research that is not primarily geomorphological, but whose focus is mainly associated with tectonic geomorphic elements. And lastly, there are studies highlighting the formation through geochemical processes and even the geomorphic features of planed surfaces built up between the major compartments of regional reliefs (Serra do Mar and Mantiqueira). The conclusion is that none of these lines alone is able to fully explain the geomorphic genesis of the Plateau, remaining unknowns that challenge old approaches. New questions arise and old ones persist, across period to period and school to school.