Brazilian Journal of Geology最新文献_第7页

Stratigraphy and paleogeography of the Eocene in the Mosqueiro Low, Sergipe-Alagoas Basin Sergipe-Alagoas盆地Mosqueiro Low始新世地层学与古地理

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-09-24 DOI: 10.1590/2317-4889202120210028

Cristiano Camelo Rancan, R. Rohn, W. Souza-Lima, Claudio Borba

引用次数: 1

Magnetic and radiometric signatures of alkaline rocks and gabbros from the Ponta Grossa Arch, southeastern Paraná Basin, Brazil 巴西帕拉纳<e:1>盆地东南部蓬塔格罗萨拱门碱性岩石和辉长岩的磁性和辐射特征

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-08-25 DOI: 10.1590/2317-4889202120200051

V. Silva, F. J. Ferreira

{"title":"Magnetic and radiometric signatures of alkaline rocks and gabbros from the Ponta Grossa Arch, southeastern Paraná Basin, Brazil","authors":"V. Silva, F. J. Ferreira","doi":"10.1590/2317-4889202120200051","DOIUrl":"https://doi.org/10.1590/2317-4889202120200051","url":null,"abstract":"Abstract We present airborne magnetic and radiometric characteristics of some igneous suites from the Ponta Grossa Arch Alkaline Province (southern Brazil), namely the Bairro da Cruz, Banhadao, Barra do Itapirapua, Mato Preto and Tunas complexes, Barra do Teixeira Phonolite, Itapirapua Nepheline syenite, and Jose Fernandes Gabbro. We applied magnetic susceptibility 3D inversions using the total magnetic anomaly data together with its analytic signal of the vertical integral and the vertical integral of the analytic signal for the Bairro da Cruz, Jose Fernandes, and Tunas intrusions. Gamma-ray spectrometric methods involved analyses of basic, ternary, and ratio maps, thorium-normalized parameters, and radioelement concentrations at sampled data points. Stacked profiles from geophysical data were generated for each rock. The Bairro da Cruz, Jose Fernandes, and Tunas intrusions are associated with dipolar anomalies with normal polarity whereas their inversions show low magnetic susceptibility values. Gamma-ray spectrometric results allowed us to verify that all complexes are enriched mainly in eTh. Carbonatite bodies showed the highest contents of eTh and eU. Our findings are consistent with geophysical responses of alkaline bodies and impact the understanding of geophysical signatures, especially radiometric ones, of alkaline provinces in Brazil.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"9 1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87717328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hydrogeological compartmentalization and connection of the Guarani (GAS) and Serra Geral (SGAS) aquifer systems from a multiscale perspective: a case study in southern Brazil 多尺度视角下瓜拉尼(GAS)和塞拉·杰拉尔(SGAS)含水层系统的水文地质分区和连接:以巴西南部为例

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-08-25 DOI: 10.1590/2317-4889202120200056

Rafaela Chirst da Silva, F. M. Tognoli, P. R. Reginato, Paulo Salvadoretti, L. V. D. Souza

{"title":"Hydrogeological compartmentalization and connection of the Guarani (GAS) and Serra Geral (SGAS) aquifer systems from a multiscale perspective: a case study in southern Brazil","authors":"Rafaela Chirst da Silva, F. M. Tognoli, P. R. Reginato, Paulo Salvadoretti, L. V. D. Souza","doi":"10.1590/2317-4889202120200056","DOIUrl":"https://doi.org/10.1590/2317-4889202120200056","url":null,"abstract":"Abstract The Guarani (GAS) and Serra Geral (SGAS) aquifer systems are the main groundwater sources in southern Brazil. We investigated the crucial relationship between the primary, intergranular pore system in the GAS and the secondary pore system associated with fractures in the SGAS in order to understand better the compartmentalization and connection, water storage, and productivity of both aquifers. Data from 375 wells that produce from both aquifers was used to evaluate the hydrodynamic characteristics of the GAS-SGAS contact. The integration of data using remote sensing, structural data, and thin section analysis support interpretations about the compartmentalization and potential connection of the aquifers. Fault zones trending NW, EW, and NNE demarcate six structural blocks in which the GAS-SGAS contact varies more than 400 m in elevation. Thin section analysis of sandstone texture and composition allowed us to determine the relationship between the type of porosity and cement type and content. The surface demarcating the Guarani-Serra Geral contact is highly productive in 93% of the wells that reach both aquifers. The integration of our results allowed us to propose a conceptual hydrogeological model for the GAS and SGAS aquifers in the study area.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"5 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82662469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Depositional setting and U-Pb detrital record of rift-related deposits in the Moeda Formation (Minas Supergroup) at the Gandarela and Ouro Fino synclines, Quadrilátero Ferrífero, Brazil 巴西Gandarela和Ouro Fino向斜Moeda组(Minas超群)裂谷相关矿床的沉积环境和U-Pb碎屑记录

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-08-13 DOI: 10.1590/2317-4889202120200023

Rafael da Silva Madureira, M. Martins, G. Queiroga, C. Lana, Luiz Fernandes Dutra, A. Alkmim

{"title":"Depositional setting and U-Pb detrital record of rift-related deposits in the Moeda Formation (Minas Supergroup) at the Gandarela and Ouro Fino synclines, Quadrilátero Ferrífero, Brazil","authors":"Rafael da Silva Madureira, M. Martins, G. Queiroga, C. Lana, Luiz Fernandes Dutra, A. Alkmim","doi":"10.1590/2317-4889202120200023","DOIUrl":"https://doi.org/10.1590/2317-4889202120200023","url":null,"abstract":"Abstract The Moeda Formation (Caraca Group, base of Minas Supergroup) registers the initial rift stages of the Minas Basin in the Quadrilatero Ferrifero, Southern Sao Francisco craton, SE-Brazil. We present stratigraphic and U-Pb detrital zircon dating analyses of the Moeda Formation that contribute to the comprehension of its sedimentary evolution in the southernmost Gandarela and Ouro Fino synclines (Central-Eastern Quadrilatero Ferrifero). The Moeda Formation sequence consists of a basal proximal alluvial fan with clast-supported conglomerates, grading upward into an alluvial floodplain with quartz arenites, and upper massive sandstones from distal fluvial fans. Because the Moeda Formation is normally limited by similar lithologies at both its base (Nova Lima Group, Rio das Velhas Supergroup) and top (Batatal Formation, uppermost Caraca Group) and stratigraphic inversion has occurred in the study area, U-Pb detrital zircon dating was also extended to these units to differentiate them stratigraphically. The youngest clusters of detrital zircon ages in the Nova Lima Group and Moeda and Batatal formations were 2716, 2777 and 2786 Ma, respectively. Based on our data and relevant literature, the depositional age of the Moeda Formation was interpreted as between 2716 and 2520 Ma with the Mesoarchean continental crust, the Rio das Velhas Supergroup and the Archean TTG complexes as its main source areas.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"149 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86658321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Late Ediacaran lateral-escape tectonics as recorded by the Patos shear zone (Borborema Province, NE Brazil) 巴西东北部borborrema省帕托斯剪切带记录的晚埃迪卡拉世侧向逃逸构造

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-05-28 DOI: 10.1590/2317-4889202120200132

C. Archanjo, M. Hollanda, Luís Gustavo Ferreira Viegas

{"title":"Late Ediacaran lateral-escape tectonics as recorded by the Patos shear zone (Borborema Province, NE Brazil)","authors":"C. Archanjo, M. Hollanda, Luís Gustavo Ferreira Viegas","doi":"10.1590/2317-4889202120200132","DOIUrl":"https://doi.org/10.1590/2317-4889202120200132","url":null,"abstract":"Abstract Lateral escape tectonics mediated by strike-slip fault zones are an efficient mechanism of rock deformation in the continental crust of collision zones. The Borborema shear zone system, which shows dimensions comparable to the Cenozoic extrusion of Indochina, defines a lateral escape setting of the Brasilano orogeny in Northeastern Brazil. In this paper, the timing of high-grade metamorphism and compositions of the terranes involved in the shear deformation were investigated. The Patos shear corridor deforms the Siderian to Neoarchean rocks of the Granjeiro Complex that, in turn, form the basement of Serido-Lavras da Mangabeira metapelites. U-Pb zircon ages and Sm-Nd whole-rock isotopic compositions indicate that the 2.80 – 2.35 Ga basement sequences mainly include juvenile material, whereas zircons from synkinematic migmatites indicate that the partial melting occurred in the Late Ediacaran (ca. 565 Ma). Cooling rates provided by 40Ar/39Ar range from 12 to 17°C/Ma, indicating a differential shear zone exhumation, in agreement with a transpressive setting. The presence of allochthonous Siderian sequences dismembered along the shear zone suggests that the Serido-Granjeiro corridor defines a major tectonic boundary connected to the collisional front defined by the convergence of Sao Francisco-Congo and Amazonian cratons.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"2 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82397995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Water level alterations on the southern rim of the Guarani Aquifer due to the rain regime 由于降雨制度，瓜拉尼含水层南缘的水位变化

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-05-14 DOI: 10.1590/2317-4889202120200079

Vanessa da Conceição Osório, C. Moura

引用次数: 1

Cyclicity and hierarchy in sequence stratigraphy: an integrated approach 层序地层学中的旋回性与层次性:一种综合方法

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-05-14 DOI: 10.1590/2317-4889202120200106

D. G. C. Fragoso, G. Gabaglia, A. Magalhães, C. Scherer

{"title":"Cyclicity and hierarchy in sequence stratigraphy: an integrated approach","authors":"D. G. C. Fragoso, G. Gabaglia, A. Magalhães, C. Scherer","doi":"10.1590/2317-4889202120200106","DOIUrl":"https://doi.org/10.1590/2317-4889202120200106","url":null,"abstract":"Abstract With standardized methodology and nomenclature, the sequence stratigraphy aims to characterize multi-scale cyclical units of genetically related rocks into a hierarchical chronostratigraphic framework. From facies to basin scale, the stacking patterns and stratigraphic surfaces are recognized as sequence elements. In parallel, Earth sciences have developed a sophisticated understanding of geological processes (tectonic, climatic, and eustatic) that produce the main cyclicity observed in the sedimentary rock record. This review paper discusses how the elaboration of hierarchical stratigraphic frameworks that incorporate the knowledge of these periodic geological processes — from high- to low-frequencies — as the control of generation and preservation of sequences — from high- to low-resolutions — guarantees objective results in predicting vertical recurrence and the lateral correlation of genetic stratigraphic units. This interpretive approach of cyclic stratigraphic analysis supports the development of effective observable criteria to identify and rank sequences in multiple scales, based on cycle anatomy, recurrence, vertical trends, and mappability. This methodological improvement reduces the inaccuracies and contradictions of traditional conceptual models based on fully preserved three-dimensional depositional systems.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"27 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82305084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

A singular Hegetotheriinae (Notoungulata, Typotheria) from the late Oligocene-Early Miocene of the Subandean Region of Bolivia 来自玻利维亚亚的斯亚贝巴地区渐新世晚期-中新世早期的单一Hegetotheriinae (Notoungulata, Typotheria)

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-05-14 DOI: 10.1590/2317-4889202120200067

M. Reguero, D. Tineo, Paula Bona, L. Pérez, G. Vergani, Gloria González Ruiz, D. Poiré

{"title":"A singular Hegetotheriinae (Notoungulata, Typotheria) from the late Oligocene-Early Miocene of the Subandean Region of Bolivia","authors":"M. Reguero, D. Tineo, Paula Bona, L. Pérez, G. Vergani, Gloria González Ruiz, D. Poiré","doi":"10.1590/2317-4889202120200067","DOIUrl":"https://doi.org/10.1590/2317-4889202120200067","url":null,"abstract":"Abstract Geological studies in the northern sector of the Chaco foreland Basin, Bolivia, yielded new fossils coming from late Oligocene-late Miocene of the Petaca Formation. Few fossil mammals were known from the Subandean Region of Bolivia. We report a partially complete mandible of a hegetotheriid Hegetotheriinae (Notoungulata, Typotheria) from Abapo (Rio Grande River). The specimen (YPFB-LIT-PAL-005) is very close in size and dental morphology to the late Oligocene (Deseadan South American Land Mammal Age, SALMA) — Santacrucian (early Miocene) Prohegetotherium schiaffinoi (Kraglievich 1932) from Fray Bentos (Uruguay and Argentina), Salla (Bolivia), Divisadero Largo-Potrerillos and Quebrada Fiera (Argentina). However, mandibular characteristics, as the shape with a marked change in height along its length, increasing towards the back, a prominent masseteric crest, a deep mandibular groove, and a remarkable thickening of the ventral rim of the mandible, indicate differences between this specimen and Prohegetotherium schiaffinoi and the other Hegetotheriinae. The affinity of YPFB-LIT-PAL-005 with P. schiaffinoi suggests a late Oligocene to early Miocene for the upper bearing horizon of the Petaca Formation (in Abapo), an older age than previously assigned to the top of this unit (late Miocene), and confirms the taxon distribution between ∼ 36 ° to ∼ 17 ° south latitude.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"10 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74259871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Open-system magmatic evolution and crystallization conditions of the Ediacaran shoshonitic rocks from the São João do Sabugi Pluton, Borborema Province, NE Brazil 巴西东北部borborrema省<s:1> o jo<e:1> o do Sabugi岩体埃迪卡拉纪浅玄岩的开放体系岩浆演化与结晶条件

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-05-14 DOI: 10.1590/2317-4889202120200040

Dayvison Bruno Cordeiro de Paiva, F. C. Vilalva, Z. Souza, M. Nascimento

{"title":"Open-system magmatic evolution and crystallization conditions of the Ediacaran shoshonitic rocks from the São João do Sabugi Pluton, Borborema Province, NE Brazil","authors":"Dayvison Bruno Cordeiro de Paiva, F. C. Vilalva, Z. Souza, M. Nascimento","doi":"10.1590/2317-4889202120200040","DOIUrl":"https://doi.org/10.1590/2317-4889202120200040","url":null,"abstract":"Abstract The Sao Joao do Sabugi Pluton (SJSP) (∼579 Ma) is one of the most expressive occurrences of Ediacaran, syn- to post-collisional shoshonitic rocks in the Rio Piranhas-Serido Domain, Borborema Province, NE Brazil. The petrography, whole rock and mineral composition of this pluton were investigated to characterize its open-system magmatic differentiation processes. The pluton is composed of three rock groups: gabbro-diorite, with clinopyroxene ± orthopyroxene ± amphibole ± biotite; monzodiorite, with amphibole and biotite (± pyroxenes); and granodiorite, with biotite as the main mafic mineral. Evidences of open-system processes, including partially resorbed metasediment xenoliths, are widespread. These rocks are metaluminous, alkali-calcic and magnesian, and have shoshonitic affinity. They show relative LILE and LREE enrichment and pronounced negative Nb-Ta anomalies. Major and trace element geochemical modeling favors magma differentiation by fractional crystallization (56–62%) after crustal assimilation of ∼30% of local paragneisses and schists from the Serido Group in a relatively stationary magma chamber at crustal depth, under pressures of 5–6 kbar, temperatures of ∼800–1,000°C and relatively oxidizing conditions. The less evolved gabbro-diorite was generated by ∼18% modal dynamic partial melting of a metasomatized mantle source.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83049130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Landslide recognition using SVM, Random Forest, and Maximum Likelihood classifiers on high-resolution satellite images: A case study of Itaóca, southeastern Brazil 在高分辨率卫星图像上使用支持向量机、随机森林和最大似然分类器进行滑坡识别:以巴西东南部Itaóca为例

IF 1.4 4区地球科学

Brazilian Journal of Geology Pub Date : 2021-01-01 DOI: 10.1590/2317-4889202120200105

H. C. Dias, L. Sandre, Diego Alejandro Satizábal Alarcón, C. Grohmann, J. A. Quintanilha

{"title":"Landslide recognition using SVM, Random Forest, and Maximum Likelihood classifiers on high-resolution satellite images: A case study of Itaóca, southeastern Brazil","authors":"H. C. Dias, L. Sandre, Diego Alejandro Satizábal Alarcón, C. Grohmann, J. A. Quintanilha","doi":"10.1590/2317-4889202120200105","DOIUrl":"https://doi.org/10.1590/2317-4889202120200105","url":null,"abstract":"Landslide identification is important for understanding their conditioning factors, and for constructing susceptibility, risk, and vulnerability maps. In remote sensing this can be accomplished manually or through classifiers. This study compares three image classifiers (Maximum Likelihood, Random Forest, and Support Vector Machines (SVM)) used in identifying landslides in Itaóca (São Paulo, Brazil). Two datasets were used: a RapidEye-5 (5 m) image and a Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) (12.5 m). Seven pixel-based classifications were produced, two for each classifier and a binary class that identified only landslides and non-landslides. One classification contained five spectral bands (5B), while the other contained six bands (6B) and included the slope derived from the DEM. The results were validated using Kappa index and F1 score. The SVM 6B classification achieved the best results among the validation indices used herein. It identified a landslide area of 399,325 m². The results contribute to landslide mapping in tropical environments using pixel-based classifiers. However, although the SVM classification was successful, only landslides with larger areas were captured by the algorithms, con-firming the importance of conducting further analyses using images with finer spatial resolution.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"176 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76945875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7