An adequate management of geological heritage by national and regional authorities presupposes the existence of a solid geosites inventory. Unfortunately, this is not the case for many countries. Most often, there is no national inventory at all or the method and criteria used to assess geosites was not adequate. This paper makes an overview of the strengths and weaknesses of the most common procedures to produce a geosite inventory and proposes a methodology particularly adapted for large territories such as Brazil. Nevertheless, this methodological approach can be easily adapted to any other geographical or geological setting, promoting the characterization and conservation of the world's geological heritage.
MORPHOTECTONICS OF THE CURITIBA SEDIMENTARY BASIN The morphostructural framework differentiation in the Precambrian/Eo-Paleozoic basement and Cenozoic sedimentary cover of the Metropolitan Area of Curitiba is due to extensional and transtensional neotectonic movements, with the concurrence of climatic changes. Drainage morphometric analysis indicates tectonic influence in the morphogenetic processes. Structural alignments control the sub-rectangular and sub-parallel patterns of the drainage system, the asymmetry of the second-order drainage sub-basins of the Iguaçu basin river, the main local base level, and the geometry of the Cenozoic sediments, including the alluvial deposits, which present asymmetric spatial distribution and narrowing segments in areas of crossed-alignments. The main second order tributaries of the Iguaçu river, like the Pequeno and Barigüi rivers, present tectonically controlled channels, as indicated by the coincidence of anomalies with older structures reactivated since the Lower Tertiary, as well as scarps that may be clearly observed in digital elevation models, even not so accentuated. The higher northnorthwestern margin inclination of the Iguaçu River in relation to its south-southeastern margin is a salient morphostructural characteristic related with the Upper Iguaçu Fault, which deformed the Curitiba sedimentary basin and to which part of the upper Iguaçu valley is adjusted. The fault was active during and after the Pleistocene, reflecting the more recent neotectonic activity, and may be recognized through the faulted colluvial-alluvial deposits and the weak seismic activities in the Serra do Mar.
The Paraná basin is one of the major morphotectures of the South American continent. Although its tectono-sedimentary evolution has been widely studied and fairly well understood, this paper aims to fill a gap in knowledge comprising the tectonic evolution after the end of its last sedimentary cycle, in the Upper Cretaceous. In this context, the Jordan River watershed, situated in the surroundings of Guarapuava municipality, south central region of Paraná State, was selected for structural and morphometric analysis where the Cretaceous volcanic rocks of Serra Geral Formation are exposed. The Jordan River watershed was studied for the influence exerted by Taxaquara Fault Zone on its morphologic evolution, since Taxaquara Fault Zone is associated to the Brazilian cycle and extends eastwards to the Ribeira belt in the state of São Paulo. The morphometric analysis consisted in the interpretation of the Jordan River watershed drainage network and relief elements, considering the distribution of existing knickpoints in the water courses. Structural analysis was based on the calculation of the stress fields responsible for the activation of local fault zones, which were determined by their spatial arrangement and the statistical and mechanical treatments of structural data. During the Oligocene and Miocene, erosional processes developed a planing surface which marks the relief in the central region of the Jordan River watershed and serves as a stratigraphic marker for the associated deformational events. Three events that contributed to the morphological framework of the Jordan River watershed were defined: an oldest one, probably active before the development of the Jordan pediplane in the Paleogene, by a NE-SW maximum horizontal stress (SHmax); and two more recent ones, being one of Plio-Pleistocene age, with a N05W SHmax, and a still active event of transtensive nature showing a N75W SHmax. The paleostress analysis points to a similarity between the Cenozoic evolution of Paraná Basin and the tafrogenic basins of southeast Brazil, revealing the amplitude of the deformation events associated to the studied period and ensuring the importance of further studies on the morphotectonic evolutions of intracratonic regions of the South American plate and their correlation to the Andean tectonic cycle.
Resumo No arcabouço estrutural do Complexo Atuba a deformação atual ou pré-atual ocorre em regime rúptil decorrente de falhas recentes ou reativadas segundo um sistema transcorrente dominante. Além das falhas na escala regional que coincidem com reativações dos já existentes alinhamentos NE-SW e NW-SE, foram geradas novas estruturas a partir do Neógeno com característica distensiva e cisalhante concordantes com o vetor de tensão principal (σ 1), horizontal e orientado para N-S. Associado às estruturas N-S ocorre um sistema conjugado transcorrente proeminente nas direções N20-35E e N20-35W. As falhas destas famílias são responsáveis pelo deslocamento de diques de diabásio e lamprófiros. O mesmo sistema transcorrente provoca estrias de atrito nos gnaisses, assim como estruturas sub-verticais conjugadas que se estendem na cobertura sedimentar da Bacia de Curitiba. Além do sistema transcorrente ocorrem grandes falhas inversas de baixo mergulho (20 o a 30 o) nas direções próximas a N20W/35NE e N20E/20NW cujo cisalhamento rúptil gera brecha cataclástica nos gnaisses e deslocamentos em diques. Estas zonas de cisalhamento rúptil estão seccionadas pelos planos associados ao sistema transcorrente antes mencionado. Tal estruturação e sua cinemática permitem caracterizar melhor o evento D2' de Salamuni (1998), cujo campo de tensão atual ou pré-atual apresenta a tensão principal σ 1 na direção N-S. Em termos cronológicos o posicionamento proposto para o campo tensão, caracteriza ciclos ou episódios transtensivos decorrentes de deformações secundárias do regime compressional D2 quando σ 1 anteriormente posicionado aproximadamente na direção E-W passa a orientar-se, pelo menos episodicamente, a partir do fim do Pleistoceno na direção NNW-SSE ou N-S.
RESUMOEste trabalho tem por objetivo apresentar os passos da construção de um sistema de banco de dados (BD) geo-referenciados com informações geológicas e geomorfológicas da Bacia Sedimentar de Curitiba como base de um Sistema de Informação Geográfica (SIG). O banco de dados foi preparado através de cartografia geológica, dados de sondagens para poços tubulares profundos, fotografias de afloramentos e tabelas com descrições geológicas de afloramentos na região de Curitiba e arredores. O sistema foi montado inicialmente no Arc/Info ® v. 7.0.3 (Esri 1994) e no ArcView GIS ® v.3.2 (Esri 1999), respectivamente em ambiente Unix-HP ® e Windows ® , e possibilita o acesso automático de níveis de informações, de forma concomitante ou não, através da tela do computador, por meio de várias ferramentas do próprio ArcView GIS ® v.3.2. (Esri 1999) Para a operação do BD, todos os dados que o integram e suas bases cartográficas digitais precisam estar necessariamente geo-referenciados e com topologia criada. A inter-relação entre as informações acessadas permite a construção de outros produtos cartográficos, a partir daquele original, dentro do mesmo ambiente que se está operando. Tanto a entrada de dados quanto sua manipulação em tempo real é possível graças às ferramentas disponíveis dentro do programa, tornando a atualização da base de dados um procedimento bastante simples e, portanto, resguardando a contínua utilidade e otimização do sistema. Os Modelos Digitais de Elevação (MDE) e a topologia de elementos cartográficos, ou não, foram gerados no Arc/Info ® v. 7.0.3 (Esri 1994). O ArcView GIS ® v. 3.2 (Esri 1999) se mostrou interativo com o usuário facilitando o acesso à informação e permitindo que o banco de dados possibilite o processo de tomada de decisão, condição essencial para um sistema de informações automáticas. ABSTRACTThe aim of this paper is to present a georeferenciated data bank (DB) with geological and geomophological information of the Curitiba Sedimentary Basin as a base to build a Geographic Information
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