scholarly journals CLAY MINERALS AND GAMMA-RAY SPECTROMETRY AS PALEOCLIMATIC INDICATORS IN THE GONDWANA’S SEDIMENTARY SEQUENCES, SANTA CATARINA, BRAZIL

2018 ◽  
Vol 36 (3) ◽  
pp. 1
Author(s):  
Hérlon da Silva Costa ◽  
Marivaldo dos Santos Nascimento ◽  
Francisco José Fonseca Ferreira
Keyword(s):  
Clay Minerals ◽  
Chemical Weathering ◽  
Gamma Ray ◽  
Climatic Conditions ◽  
Gamma Ray Spectrometry ◽  
Sedimentary Sequences ◽  
Chemical Index ◽  
Paraná Basin ◽  
Parana Basin ◽  
Eastern Edge

ABSTRACT. This work presents clay minerals data and gamma-spectrometry to accesses the paleoclimatic signature during the depositional transition from Taciba to the Rio Bonito Formation in the eastern edge of the Paraná Basin. Detrital illite content (50 to 60%) and chemical index alteration indicates low-influence of chemical weathering. The eTh/K and eTh/eU ratios and detrital illite in the Rio Bonito Formation indicate a cold and dry climate during deposition. The contrast between the increase in eTh/K and eTh/eU ratios and the decrease in the illite content toward the top of the Rio Bonito Formation suggests progressively warmer and humid climatic conditions. The cycling in the eTh/K and eTh/eU ratios clearly indicate seasonal variations in temperature and leaching of K and eU.Keywords: Paleoclimate, Rio do Sul Formation and Rio Bonito Formation, Paraná Basin. RESUMO. Este trabalho apresenta dados de argilominerais e gamaespectrometria para acessar a assinatura paleoclimática durante a transição deposicional da Formação Taciba para a Formação Rio Bonito na borda leste da Bacia do Paraná. O conteúdo de ilita detrítica (50 a 60%) e a alteração do índice químico indicam baixa influência do intemperismo químico. As relações eTh/K e eTh/eU e ilita detrítica na Formação Rio Bonito indicam um clima frio e seco durante a deposição. O contraste entre o aumento das razões eTh/K e eTh/eU e a diminuição do conteúdo de ilitas em direção ao topo da Formação Rio Bonito sugerem condições climáticas progressivamente mais quentes e úmidas. A ciclagem nas razões eTh/K e eTh/eU indica claramente variações sazonais na temperatura e lixiviação de K e eU. Palavras-chave: Paleoclima, Formação Rio do Sul e Formação Rio Bonito, Bacia do Paraná. 1Federal

scholarly journals Identificação de Cicatrizes de Movimentos de Massa na Borda Oriental da Bacia do Paraná com base em Imagens Landsat 5-TM (Identification of Landslides Scars in the Eastern Edge of the Paraná Basin)

2015 ◽  
Vol 8 (1) ◽  
pp. 056
Author(s):  
Mariana Madruga De Brito
Keyword(s):  
Image Processing ◽  
Mass Movement ◽  
Google Earth ◽  
Economic Losses ◽  
Mass Movements ◽  
Tm Image ◽  
Paraná Basin ◽  
Landsat 5 Tm ◽  
Parana Basin ◽  
Eastern Edge

Movimentos de massa são fenômenos naturais caracterizados pelo deslocamento de solo e rocha vertente abaixo. Quando esses processos ocorrem em áreas urbanizadas, podem causar perdas econômicas, impactos sociais e, em casos extremos, perda de vidas humanas. Na tentativa de mitigar tais desastres, torna-se necessário mapear os locais já afetados pelos mesmos, uma vez que escorregamentos recentes podem sugerir futuros padrões de instabilidade. Nesse sentido, este trabalho teve por objetivo mapear as cicatrizes de movimentos de massa em um segmento da Borda Oriental da Bacia do Paraná, por meio do processamento de uma imagem Landsat 5-TM, órbita/ponto 220/80, data de passagem 28/08/2009. Para facilitar a discriminação destas feições, elaboraram-se composições coloridas RGB e processamentos tais como Ampliação Linear de Contraste (ALC), razão entre bandas e Análise por Componentes Principais (PCA). A fim de validar o inventário elaborado, utilizaram-se imagens de alta resolução disponíveis no software Google Earth®. Ao total, foram identificadas 63 cicatrizes com a imagem Landsat 5-TM e 121 cicatrizes com as imagens do Google Earth®. Os principais tipos de movimentos de massa mapeados são escorregamentos translacionais rasos e corrida de detritos. A identificação das cicatrizes foi possível devido às diferenças de tonalidade, cor, matiz e textura nas imagens orbitais após a ocorrência desses processos. Os resultados obtidos representam um passo inicial para a análise da suscetibilidade da área.     A B S T R A C T Mass movements are natural phenomena characterized by the downslope movement of soil and rock. When these processes occur in urban areas they can cause economic losses, social impacts and, in extreme cases, loss of human lives. In an attempt to mitigate such disasters, it is necessary to map sites affected by them, since recent landslides may suggest future patterns of instability. In this sense, this study aimed to map the mass movement scars in a segment of the Eastern Edge of the Paraná Basin, through the processing of a Landsat 5-TM image, 220/80 orbit-point and date of passage 08/28/2009. To facilitate the recognition of these features, RGB color compositions and image processing techniques such as contrast stretching, ratio between bands and Principal Component Analysis (PCA) were applied. In order to validate the inventory, high-resolution images available at Google Earth® software were used. Totally, 63 scars were identified with the Landsat 5-TM image and 121 with Google Earth® images. The main types of mass movements mapped are translational landslides and debris flows. The identification of the scars was possible due to differences in tone, color, hue and texture at the orbital images after the occurrence of such processes. Results obtained represent an initial step towards the susceptibility analysis of the area. Keywords: Landslide inventory; Digital image processing; Satellite images; Geoprocessing.  

scholarly journals Geochemical Significance of Clay Minerals and Elements in Paleogene Sandstones in the Center of the Northern Margin of the Qaidam Basin, China

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 505 ◽  
Author(s):  
Guoqiang Sun ◽  
Meng Wang ◽  
Jiajia Guo ◽  
Yetong Wang ◽  
Yongheng Yang
Keyword(s):  
Clay Minerals ◽  
Chemical Weathering ◽  
Qaidam Basin ◽  
Sedimentary Environment ◽  
Climatic Conditions ◽  
Northern Margin ◽  
Magmatic Arc ◽  
Average Value ◽  
Geochemical Significance ◽  
Continental Magmatic Arc

The average thickness of Paleogene sandstones reaches about 3000–4000 m at the northern margin of the Qaidam Basin. However, the provenance and sedimentary environment of these sandstones are uncertain; thus, more comprehensive research is needed. Integrated research is conducted on the provenance and weathering process based on petrographic characteristics, clay minerals, and geochemical compositions of sandstones in the center of the northern Qaidam Basin. The results of lithofacies analysis show that the Paleogene sandstones were mainly derived from an active continental magmatic arc, subduction accretion, or a fold-thrust belt. The average illite content in the Paleogene clay minerals is more than 50%, followed by chlorite and smectite, which reflect climatic and environmental characteristics that were arid to semi-arid, whereas the characteristics of carbon–oxygen isotopes reveal a mainly freshwater sedimentary environment. The corrected chemical index of alteration (CIAcorr) is between 56.3 and 75.7, with an average value of 66.5. These results indicate that the provenance of the Paleogene sandstones in the center of the northern Qaidam Basin mainly formed under cold and dry climatic conditions and experienced limited chemical weathering with a small amount that underwent intermediate chemical weathering under warm and humid conditions.

Comparative evolution of clay minerals in southern Paraná Basin (Brazil): Implications for triassic paleoclimate

2019 ◽  
Vol 90 ◽  
pp. 181-190 ◽  
Author(s):  
Isaque C. Rodrigues ◽  
Ana M.P. Mizusaki ◽  
Laís G. Lima ◽  
Anderson J. Maraschin
Keyword(s):  
Clay Minerals ◽  
Paraná Basin ◽  
Parana Basin ◽  
Comparative Evolution

Chemical weathering rates of clastic sedimentary rocks from the Paraná Basin in the Paulista Peripheral Depression, Brazil

2019 ◽  
Vol 96 ◽  
pp. 102369 ◽  
Author(s):  
Eder Paulo Spatti Júnior ◽  
Fabiano Tomazini da Conceição ◽  
Alexandre Martins Fernandes ◽  
Diego de Souza Sardinha ◽  
Amauri Antonio Menegário ◽  
...  
Keyword(s):  
Chemical Weathering ◽  
Sedimentary Rocks ◽  
Weathering Rates ◽  
Paraná Basin ◽  
Clastic Sedimentary ◽  
Parana Basin

scholarly journals Source Area Weathering, Paleo-Environment and Paleo-Climatic Conditions of Soils from Bitumen Rich Ode Irele Area of Ondo State, Nigeria

2019 ◽  
Vol 4 (3) ◽  
pp. 59-67
Author(s):  
Romanus Ayoola Obasi ◽  
Henry Y. Madukwe ◽  
Temitope Olaosun
Keyword(s):  
Clay Minerals ◽  
Inductively Coupled Plasma ◽  
Saline Water ◽  
Source Area ◽  
Climatic Conditions ◽  
Source Rocks ◽  
Inductively Coupled ◽  
Anoxic Environments ◽  
Chemical Index ◽  
Ondo State

The study is aimed at determining the source-weathering, paleo-redox and paleoclimatic conditions of soil from Ode Irele area of Ondo State, Nigeria. X-Ray Fluorescence (XRF) and the Laser Ablation Inductively Coupled Plasma-Mass Spectrometry ICP-MS) analyses wereusd to determine the major, trace and rare earth element compositios used for the study. The Chemical index of alteration (CIA), Chemical index of weathering (CIW), Plagioclase index of alteration (PIA), Mineralogical index of alteration (MIA), Th/U nd a plot of CIA against Al2O3 as well as the A-CN-K Ternary diagram suggest a high degree of weathering of the source rocks. The positive correlation between Al2O3 with TiO2, K2O, Fe2O3 and MgO implies that they occur in clay minerals formed from weathering. The average K2O/Al2O3 ratios of the investigated samples is ≈0.006, which suggests prevalence of clay minerals relative to other minerals. Low U/Th ratio ranging between 0.14 and 0.50 (average 0.18) relative to PAAS (0.21) and UCC (0.26) suggests deposition under oxic conditions. V/Vi + Ni ratios indicate suboxic to anoxic environment of deposition. However, plots of V/V+ Ni vs Ni/Co and V/Cr vs Ni/Co indicate oxic, dysoxic and suboxic to anoxic environments all suggesting deposition under oxic and suboxic conditions. The Ode Irele sediments was deposited in low saline water with a strong continental rather than marine influence in an arid and semi-arid climatic condition; the low average ratio of P2O5/Al2O3 (0.014) is in unison with freshwater environments.

scholarly journals O DEVONIANO NO ESTADO DO MATO GROSSO DO SUL, BRASIL: NOVA ÁREA DE DISTRIBUIÇÃO E PRESENÇA DE TÍPICA FAUNA MALVINOCÁFRICA

2020 ◽  
Vol 30 (2) ◽  
pp. 38-76
Author(s):  
Sandro Scheffler ◽  
Rafael da Silva ◽  
Daniel Sedorko
Keyword(s):  
The State ◽  
Mato Grosso ◽  
Distribution Maps ◽  
Paraná Basin ◽  
Parana Basin ◽  
Eastern Edge ◽  
Mato Grosso Do Sul ◽  
Late Emsian

Devonian strata are widely known for the eastern edge of the Paraná Basin, particularly in the state of Paraná. However, studies are still scarce on the northwestern border, especially in the state of Mato Grosso do Sul. During the studies, around 120 geological and paleontological sites in the region were identified, and some discrepancies were identified in the distribution maps of the Devonian units (Campos Gerais / Chapada Group) in that state. This paper presents a review on the Devonian strata distribution in Mato Grosso do Sul state, as well a survey of paleontological works in the region of occurrence of the climax Malvinokaffric fauna (Pragian-early Emsian) in order to increase the discussion about the genesis of Devonian deposits. This fauna, combined with other stratigraphic evidences, corroborates a non-compartmentalization of the Paraná Basin for this age. The hypothesis of a tectonism concomitant with the deposition of the Ponta Grossa Formation (=lower Chapada II Group) is raised, mainly to the top of the unit, corroborated by a progradational context followed by a depositional hiatus during the middle Emsian at the end of the Eifelian in the area. It is possible that the Campo Grande Arch only acquired geomorphological expressiveness during the middle Emsian which would be attested by the absence of strata dated as late Emsian / Eifelian in croping areas in the state.

scholarly journals ELECTROFACIES CLASSIFICATION OF PONTA GROSSA FORMATION BY MULTI-RESOLUTION GRAPH-BASED CLUSTERING (MRGC) AND SELF-ORGANIZING MAPS (SOM) METHODS

2020 ◽  
Vol 38 (1) ◽  
pp. 52
Author(s):  
Felipe Vasconcelos dos Passos ◽  
Marco Antonio Braga ◽  
Thiago Gonçalves Carelli ◽  
Josiane Branco Plantz
Keyword(s):  
Gamma Ray ◽  
Clustering Algorithms ◽  
Clustering Methods ◽  
Self Organizing Maps ◽  
Resolution Graph ◽  
Lithology Prediction ◽  
Paraná Basin ◽  
Parana Basin ◽  
Graph Based Clustering ◽  
Self Organizing

ABSTRACT. In Ponta Grossa Formation, devonian interval of Paraná Basin, Brazil, sampling restrictions are frequent, and lithological interpretations from gamma ray logs are common. However, no single log can discriminate lithology unambiguously. An alternative to reduce the uncertainty of these assessments is to perform multivariate analysis of well logs using data clustering methods. In this sense, this study aims to apply two different clustering algorithms, trained with gamma ray, sonic and resistivity logs. Five electrofacies were differentiated and validated by core data. It was found that one of the electrofacies identified by the model was not distinguished by macroscopic descriptions. However, the model developed is sufficiently accurate for lithological predictions.Keywords: geophysical well logging, lithology prediction, Paraná Basin. CLASSIFICAÇÃO DE ELETROFÁCIES DA FORMAÇÃO PONTA GROSSA UTILIZANDO OS MÉTODOS MULTI-RESOLUTION GRAPH-BASED CLUSTERING (MRGC) E SELF-ORGANIZING MAPS (SOM)RESUMO. Na Formação Ponta Grossa, intervalo devoniano da Bacia do Paraná, Brasil, restrições de amostragem são frequentes e interpretações litológicas dos registros de raios gama são comuns. No entanto, nenhum perfil geofísico único pode discriminar litologias sem ambiguidade. Uma alternativa para reduzir a incerteza dessas avaliações é executar uma análise multivariada combinando vários perfis geofísicos de poços por meio de métodos de agrupamento de dados. Nesse sentido, este estudo tem como objetivo aplicar dois algoritmos de agrupamento aos registros de raios gama, sônico e resistividade para fins de predição litológica. Cinco eletrofácies foram diferenciadas e validadas por dados de testemunhos. Verificou-se que uma classe identificada pelo modelo não foi identificada por descrições macroscópicas. Porém, o modelo é suficientemente preciso para predições litológicas.Palavras-chave: geofísica de poços, predição litológica, correlação rocha-perfil, Bacia do Paraná.

scholarly journals EARLY DEVONIAN TAPHOFLORA RECORD IN PONTA GROSSA ARCH, PARANÁ BASIN (SOUTHERN BRAZIL) AND ITS PALAEOGEOGRAPHIC IMPLICATIONS / REGISTRO DA TAFOFLORA DEVONIANA NO ARCO DE PONTA GROSSA, BACIA DO PARANÁ (SUL DO BRASIL) E SUAS IMPLICAÇÕES PALAEOGENOGRAFICAS

2018 ◽  
Vol 3 (2) ◽  
pp. 93-107 ◽  
Author(s):  
Ingrid De Melo Milagres ◽  
Egberto Pereira ◽  
Sérgio Bergamaschi ◽  
Maria Antonieta Da Conceição Rodrigues ◽  
Philippe Gerrienne
Keyword(s):  
Lower Devonian ◽  
Climatic Conditions ◽  
South Pole ◽  
Southern Brazil ◽  
The South ◽  
Early Devonian ◽  
Terrestrial Environments ◽  
Paraná Basin ◽  
Eastern Border ◽  
Parana Basin

This work analyzes the taphofloras collected from two Lower Devonian localities (PISA and Ponta Grossa/Carambeí) of the eastern border of the Paraná Basin (Southern Brazil). This association is of late Lochkovian age. It includes a large number of records of Cooksonia paranensis Gerrienne et al., 2001, as well as of other taxa representative of this age interval. The occurrence of these plants in the Paraná Basin raises questions related to the Early Devonian paleoclimatic and paleogeographic settings, mainly when compared with the coeval floras from Bolivia and Laurasia. According to the most recent paleogeographic reconstructions, the Paraná Basin was located very close to the South Pole during Early Devonian times and was under cold climatic conditions and poor insolation or even darkness during long periods. Some Brazilian primitive plants possess spine-like emergences, which may indicate protection against cold climatic conditions and desiccation and/or an attempt to increase photosynthetic surfaces. The existence of such diversified taphofloras close to the South Pole during the Early Devonian corroborates the hypothesis of an ice-free pole at this time, which allowed the development of vegetation in terrestrial environments. The taphofloras of the Paraná Basin are strikingly similar to those of probably coeval localities from Euramerica. The implications of these similarities are discussed in a paleogeographic context in this work.ResumoEste trabalho analisa registros de tafoflora devoniana encontrados em duas localidades (PISA e Ponta Grossa / Carambeí) do bordo leste da Bacia do Paraná (Sul do Brasil). Esta associação tem idade Lochkoviana terminal. Ela inclui um grande número de registros de Cooksonia paranensis Gerrienne et al., 2001, bem como de outros taxa representativos desse intervalo. A ocorrência destas plantas na Bacia do Paraná levanta questões relacionadas com as configurações paleoclimáticas e paleogeográficas do inicio do Devoniano, principalmente quando comparadas às floras coevas da Bolívia e da Laurásia. De acordo com as mais recentes reconstruções paleogeográficas, a Bacia do Paraná estava localizada muito perto do Pólo Sul durante o início do Devoniano e estava sob condições climáticas frias e com pouca insolação, podendo mesmo ter estado sujeita a escuridão durante longos períodos. Algumas plantas primitivas brasileiras possuem estruturas semelhantes a espinhos, o que pode indicar proteção contra condições climáticas frias e dessecação e/ou uma tentativa de aumentar superfícies fotossintéticas. A existência de tais tafofloras diversificadas próximas ao Pólo Sul durante o início do Devoniano, corrobora a hipótese da ausência de gelo na região mais meridional da Terra, neste período, favorável ao desenvolvimento da vegetação em ambientes terrestres. As tafofloras da Bacia do Paraná são notavelmente similares às das localidades provavelmente coevas da Euramérica. As implicações dessas semelhanças são discutidas num contexto paleogeográfico neste trabalho.

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