A preliminary study of the composition and community structure of the foraminifera of Chichiriviche de La Costa (Vargas, Venezuela) is presented. A total of 105 species were found in samples from 10 to 40 meter-depth, and their abundance quantified in a carbonate prone area almost pristine in environmental conditions. The general composition varies in all the samples: at 10 m, Miliolida dominates the assemblages but, as it gets deeper, Rotaliida takes control of the general composition. The Shannon Wiener diversity index follows species richness along the depth profile, meanwhile the FORAM index has a higher value at 20 m and its lowest at 40 m. Variations in the P/(P+B) ratio and high number of rare species are documented and a correspondence multivariate analysis was performed in order to visualize the general community structure. These results could set some basic information that will be useful for management programs associated with the coral reef in Chichiriviche de La Costa, which is the principal focus for diver’s schools and tourism and could help the local communities to a better understanding of their ecosystem values at this location at Vargas State, Venezuela. Keywords: Miliolida, Rotaliida, foraminiferal assemblages, FORAM index, Caribbean continental shelf.
对Chichiriviche de La Costa（委内瑞拉巴尔加斯）有孔虫的组成和群落结构进行了初步研究。在10至40米深的样本中共发现了105种物种，它们的丰度在环境条件几乎原始的碳酸盐岩易发区进行了量化。所有样本的总体组成各不相同：在10米处，Milolida在组合中占主导地位，但随着深度的加深，Rotaliida控制了总体组成。Shannon Wiener多样性指数沿着深度剖面遵循物种丰富度，同时FORAM指数在20米处具有较高的值，在40米处具有最低值。记录了P/（P+B）比率的变化和大量稀有物种，并进行了对应的多元分析，以可视化总体群落结构。这些结果可以提供一些基本信息，这些信息将有助于Chichiriviche de La Costa珊瑚礁的管理计划，该珊瑚礁是潜水员学校和旅游业的主要关注点，并有助于当地社区更好地了解其在委内瑞拉巴尔加斯州的生态系统价值。关键词：Milolida，Rotaliida，有孔虫组合，FORAM指数，加勒比大陆架。
{"title":"Preliminary foraminiferal survey in Chichiriviche de La Costa, Vargas, Venezuela","authors":"H. Carvajal-Chitty, S. Navarro","doi":"10.4072/rbp.2021.2.02","DOIUrl":"https://doi.org/10.4072/rbp.2021.2.02","url":null,"abstract":"A preliminary study of the composition and community structure of the foraminifera of Chichiriviche de La Costa (Vargas, Venezuela) is presented. A total of 105 species were found in samples from 10 to 40 meter-depth, and their abundance quantified in a carbonate prone area almost pristine in environmental conditions. The general composition varies in all the samples: at 10 m, Miliolida dominates the assemblages but, as it gets deeper, Rotaliida takes control of the general composition. The Shannon Wiener diversity index follows species richness along the depth profile, meanwhile the FORAM index has a higher value at 20 m and its lowest at 40 m. Variations in the P/(P+B) ratio and high number of rare species are documented and a correspondence multivariate analysis was performed in order to visualize the general community structure. These results could set some basic information that will be useful for management programs associated with the coral reef in Chichiriviche de La Costa, which is the principal focus for diver’s schools and tourism and could help the local communities to a better understanding of their ecosystem values at this location at Vargas State, Venezuela. Keywords: Miliolida, Rotaliida, foraminiferal assemblages, FORAM index, Caribbean continental shelf.","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48976929","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}
The floodplains of meandering rivers in southeastern Brazil represent places where the sedimentary record associated with the history of transition/ecotone areas and exchange of biomes accumulates, such as the Cerrado (Cerradão Forest) and Atlantic Forest (Semideciduous-Riparian Forest). The present study aims to use palynological, isotopic (δ13C, δ15N and 14C), and anthracological indicators in cores taken from three abandoned meander bends to make inferences about environmental evolution, vegetation reconstruction, and climatic inferences. The study area is located in the Mogi Guaçu River Basin, in the countryside of São Paulo State. The studies show that ~2,730 BP (stage I), the area underwent through a more humid climatic phase compared to the current one, which allowed the expansion of the Riparian Semideciduous Forest. After that date, in stage II (1,800 to 510 BP), the percentage of the Cerrado (Cerradão Forest) increased, due to a drier period. From 510 BP to the present day (stage III), humidity has taken place with a new expansion of the Riparian Semideciduous Forest, although elements of Cerrado are present. Microscopic charcoal fragments were found in all stages and may infer the incidence of paleo-wildfires during the Late Holocene. The results indicate that both phytophysiognomies remained for the studied period, varying their expansion depending on the humidity present in each stage. Although lakes formed by abandoned meanders are not areas with the best palynological record, they are frequent environments in the interior of the continents. If properly interpreted, they may provide relevant information to vegetation and climatic changes for the areas. Keywords: paleoenvironmental studies, Holocene, river dynamics, pollen grains, isotopic analysis, charcoal fragments.
{"title":"Evolution of the Semideciduous-Riparian Forest (ecotone Cerrado-Atlantic Forest) during the late Holocene, Southeast of Brazil","authors":"Melina Mara Souza, F. Ricardi-Branco","doi":"10.4072/rbp.2021.2.04","DOIUrl":"https://doi.org/10.4072/rbp.2021.2.04","url":null,"abstract":"The floodplains of meandering rivers in southeastern Brazil represent places where the sedimentary record associated with the history of transition/ecotone areas and exchange of biomes accumulates, such as the Cerrado (Cerradão Forest) and Atlantic Forest (Semideciduous-Riparian Forest). The present study aims to use palynological, isotopic (δ13C, δ15N and 14C), and anthracological indicators in cores taken from three abandoned meander bends to make inferences about environmental evolution, vegetation reconstruction, and climatic inferences. The study area is located in the Mogi Guaçu River Basin, in the countryside of São Paulo State. The studies show that ~2,730 BP (stage I), the area underwent through a more humid climatic phase compared to the current one, which allowed the expansion of the Riparian Semideciduous Forest. After that date, in stage II (1,800 to 510 BP), the percentage of the Cerrado (Cerradão Forest) increased, due to a drier period. From 510 BP to the present day (stage III), humidity has taken place with a new expansion of the Riparian Semideciduous Forest, although elements of Cerrado are present. Microscopic charcoal fragments were found in all stages and may infer the incidence of paleo-wildfires during the Late Holocene. The results indicate that both phytophysiognomies remained for the studied period, varying their expansion depending on the humidity present in each stage. Although lakes formed by abandoned meanders are not areas with the best palynological record, they are frequent environments in the interior of the continents. If properly interpreted, they may provide relevant information to vegetation and climatic changes for the areas. Keywords: paleoenvironmental studies, Holocene, river dynamics, pollen grains, isotopic analysis, charcoal fragments.","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45204302","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}
Julieta De Pasqua, F. Agnolín, A. M. A. Rolando, S. Bogan, Diego Gambetta
Carcharocles megalodon is considered a macropredatory shark that inhabited the seas around the world from middle Miocene to late Pliocene. In Argentina, it has only been formally recorded at two localities. Here, we report the first record for this taxon in the Buenos Aires Province. This occurrence is based on an isolated tooth recovered on the beach at the Punta Médanos locality, which lacks clear stratigraphic context. Based on the regional geology, the specimen probably came from Pliocene beds. Its size indicates that it probably belongs to a juvenile individual. Keywords: Carcharocles megalodon, macropredatory shark, fossil teeth, Mar de Ajó.
巨齿鲨被认为是一种大型鲨鱼，从中新世中期到上新世晚期居住在世界各地的海洋中。在阿根廷，只有两个地方有正式记录。在这里，我们报道了布宜诺斯艾利斯省该分类单元的第一个记录。这种情况是基于在Punta Médanos地区海滩上发现的一颗孤立的牙齿，该地区缺乏明确的地层背景。根据区域地质，该标本可能来自上新世地层。它的大小表明它可能属于一个幼年个体。关键词：巨齿鲨，大鲨鱼，牙齿化石，Mar de Ajó。
{"title":"First occurrence of the giant shark Carcharocles megalodon (Agassiz, 1843) (Lamniformes; Otodontidae) at Buenos Aires Province, Argentina","authors":"Julieta De Pasqua, F. Agnolín, A. M. A. Rolando, S. Bogan, Diego Gambetta","doi":"10.4072/rbp.2021.2.05","DOIUrl":"https://doi.org/10.4072/rbp.2021.2.05","url":null,"abstract":"Carcharocles megalodon is considered a macropredatory shark that inhabited the seas around the world from middle Miocene to late Pliocene. In Argentina, it has only been formally recorded at two localities. Here, we report the first record for this taxon in the Buenos Aires Province. This occurrence is based on an isolated tooth recovered on the beach at the Punta Médanos locality, which lacks clear stratigraphic context. Based on the regional geology, the specimen probably came from Pliocene beds. Its size indicates that it probably belongs to a juvenile individual. Keywords: Carcharocles megalodon, macropredatory shark, fossil teeth, Mar de Ajó.","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43015078","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}
Maria Alejandra Rojas-Granada, Arnol Cardozo-Rueda, Carlos Alberto Agudelo Henao, J. Guzmán, Paula Andrea Sucerquia Rendon
We report macro and meso palaeobotanical records from the Zarzal Formation, in the Cauca River Depression, and the Quindío-Risaralda Basin between the Western and the Central Cordilleras of Colombia. The fossils correspond to leaves and seeds obtained from layers of mudstones, diatomites, and tuffaceous sandstones deposited in the inter-Andean valleys of Cauca and La Vieja rivers, separated by the Serranía Santa Bárbara ridge between the Valle del Cauca and Quindío departments. The sediments of the Pleistocene Zarzal Formation were deposited in a fluvial-lacustrine environment, with volcanic influence originated in the Central Cordillera to the east of the depositional area. The study here presented allowed the identification of thirteen morphotypes of leaf impressions grouped in six Angiosperm families: Poaceae?/Cyperaceae? and Araceae of the Monocots group, Melastomataceae, Fabaceae and Lauraceae belonging to the Eudicots group and one family of Lycopsida: Thelypteridaceae. On the other hand, very well-preserved silicified micro-seeds were grouped in eight morphotypes, belonging to the botanical groups Cyperaceae and Asteraceae. The fossils found allowed us to identify two types of plant associations that exhibit paleofloristic richness. In the Cauca River Basin, an autochthonous to parautocthonous plant association could correspond to a sub-Andean gallery forest, whilst in the La Vieja River Basin a parautocthonous plant association indicates a swamped floodplain. Keywords: paleoflora, leaves, seeds, Cauca River, La Vieja River, lacustrine deposit.
我们报告了哥伦比亚科迪勒拉山脉西部和中部之间的Cauca河凹陷Zarzal组和Quindío-Risaralda盆地的宏观和中尺度古植物记录。这些化石对应于从沉积在Cauca河和La Vieja河安第斯山脉间山谷的泥岩、硅藻和凝灰质砂岩层中获得的叶子和种子，Cauca山谷和Quindío省之间的Serranía Santa Bárbara山脊将其隔开。更新世Zarzal组的沉积物沉积在河流-湖泊环境中，火山作用起源于沉积区东部的中科迪勒拉。这项研究鉴定了13种叶印痕的形态类型，分为6个被子植物科：禾本科/莎草科？和单子叶植物群的天南星科，属于真双子叶植物群和Lycopida的一个科的Melaomataceae，Fabaceae和Lauraceae：Thelypteridaceae。另一方面，保存完好的硅化微种子分为八种形态类型，属于莎草科和菊科。发现的化石使我们能够识别出两种表现出古植物区系丰富性的植物组合。在考卡河流域，本地到准水生植物群落可能对应于亚安第斯走廊森林，而在拉维耶哈河流域，准水生植物群表明泛滥平原被淹没。关键词：古植物群，叶，种子，考卡河，拉维耶哈河，湖泊沉积物。
{"title":"Pleistocene plants from Zarzal Formation, middle valley of the Cauca River Basin, Colombia","authors":"Maria Alejandra Rojas-Granada, Arnol Cardozo-Rueda, Carlos Alberto Agudelo Henao, J. Guzmán, Paula Andrea Sucerquia Rendon","doi":"10.4072/rbp.2021.2.03","DOIUrl":"https://doi.org/10.4072/rbp.2021.2.03","url":null,"abstract":"We report macro and meso palaeobotanical records from the Zarzal Formation, in the Cauca River Depression, and the Quindío-Risaralda Basin between the Western and the Central Cordilleras of Colombia. The fossils correspond to leaves and seeds obtained from layers of mudstones, diatomites, and tuffaceous sandstones deposited in the inter-Andean valleys of Cauca and La Vieja rivers, separated by the Serranía Santa Bárbara ridge between the Valle del Cauca and Quindío departments. The sediments of the Pleistocene Zarzal Formation were deposited in a fluvial-lacustrine environment, with volcanic influence originated in the Central Cordillera to the east of the depositional area. The study here presented allowed the identification of thirteen morphotypes of leaf impressions grouped in six Angiosperm families: Poaceae?/Cyperaceae? and Araceae of the Monocots group, Melastomataceae, Fabaceae and Lauraceae belonging to the Eudicots group and one family of Lycopsida: Thelypteridaceae. On the other hand, very well-preserved silicified micro-seeds were grouped in eight morphotypes, belonging to the botanical groups Cyperaceae and Asteraceae. The fossils found allowed us to identify two types of plant associations that exhibit paleofloristic richness. In the Cauca River Basin, an autochthonous to parautocthonous plant association could correspond to a sub-Andean gallery forest, whilst in the La Vieja River Basin a parautocthonous plant association indicates a swamped floodplain. Keywords: paleoflora, leaves, seeds, Cauca River, La Vieja River, lacustrine deposit.","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43576713","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}
Fatemeh Jafarbeigloo, M. Majidifard, B. Hamdi, A. Asghari, M. Arian
The Khoshyeilagh Formation located in the northeast of Iran yielded seven conodont species and sub-species and 19 macro- and microfossil taxa that allow recognition of two conodont biozones and one biozone based on calcareous microfossils. The latest Frasnian age (the Upper rhenana to linguiformis zones) is attributed to the topmost strata with Icriodus alternatus. Its replacement with I. cornutus indicates the Famennian (Lower triangularis to Lower crepida zones) corresponding to the Umbellina Zone. The fossil assemblages identified in the Khoshyeilagh Formation represent a shallow marine environment with a tropical climate at the time of deposition. The fossil species from the Khoshyeilagh Formation and the sedimentary basins in Algeria, Libya, Morocco, Poland, and Russia reveal a close connection between the Iranian plateau and the northern parts of Gondwana in the Late Devonian. The biofacies and lithofacies analyses show a sea level decline at the end of Frasnian, followed by a considerable sea level drop, as in other regions of the world. After a short time, in the Famennian, the deepening occurred in some parts of the area and the open marine facies (bioclast spicule wackestone-packstone) were deposited. This study is the first attempt to determine Frasnian-Famennian boundary based on conodont assemblages and other fossil species such as umbellulids, tentaculites, and ostracods. The distribution of these species is interpreted in sedimentological, stratigraphic, sequence stratigraphy, and the global eustatic context. Keywords: biofacies, conodont, Frasnian-Famennian boundary, Late Devonian, NE Iran. RESUMO – A Formacao Khoshyeilagh, localizada no nordeste do Ira, produziu sete especies de conodontes e subespecies e 19 taxons de macro- e microfosseis, o que permite o reconhecimento de duas biozonas de conodontes e uma biozona baseada nos microfosseis calcareos. A idade Frasniana mais superior (as zonas superiores rhenana a linguiformis) e atribuida ao estrato mais superior com Icriodus alternatus. A sua substituicao por I. cornutus indica o Famenniano (zonas iniciais triangularis superior a crepida superior), correspondendo a Zona de Umbellina. Os fosseis identificados na Formacao Khoshyeilagh representam um ambiente marinho raso, com um clima tropical, no momento de deposicao. As especies fosseis da Formacao Khoshyeilagh e as bacias sedimentares na Argelia, Libia, Marrocos, Polonia e Russia revelam uma conexao intima entre o plato iraniano e as partes norte do Gondwana no Neodevoniano. As biofacies e litofacies analisadas mostram um declinio do nivel do mar no final do Frasniano, seguido por uma consideravel queda do nivel do mar, como em outras regioes do mundo. Apos um curto tempo, no Famenniano, o aprofundamento ocorreu em algumas partes da area, e a facies marinha aberta (bioclast spicule wackestone-packstone) foi depositada. Este estudo e a primeira tentativa de determinar o limite Frasniano-Famenniano com base em associacoes de conod
位于伊朗东北部的Khoshyeilagh组发现了7个牙形石种和亚种以及19个宏观和微观化石分类群，可以识别出两个牙形石生物带和一个基于钙质微化石的生物带。最晚的frasian时代(上rhenana至linguiformis带)归因于最上层有Icriodus alternatus。它被I. cornutus取代，表明了与伞形带对应的famenian (Lower triangularis到Lower crepida区)。在Khoshyeilagh组中发现的化石组合代表了沉积时的热带气候的浅海环境。来自阿尔及利亚、利比亚、摩洛哥、波兰和俄罗斯的沉积盆地和Khoshyeilagh组的化石物种揭示了晚泥盆世伊朗高原与冈瓦纳北部地区之间的密切联系。生物相和岩相分析表明，在弗拉斯尼亚末期海平面下降，随后海平面大幅度下降，与世界其他地区一样。不久之后，在法门期，该区部分地区开始加深，形成了开阔的海相(生物碎屑针状砾岩-包覆岩)。本研究首次尝试根据牙形石组合和其他化石物种(如伞形动物、触手动物和介形虫)来确定弗拉斯纪-法门纪的边界。这些物种的分布在沉积学、地层学、层序地层学和全球海平面上升背景下得到了解释。关键词:生物相，牙形石，弗拉斯-法门世界线，晚泥盆世，伊朗东北部云南喀斯特地区，产大、微化石19个分类的牙形齿动物种和亚种，并对大、微化石的生物区带和微化石的生物区带进行了鉴定。A idade Frasniana mais superior (as zonas superires renana A linguiformis)。一种可替代的水杉(A sua substituicao popoi . cornutus indica o Famenniano)，对应于伞形带(zone de umellina)。Formacao Khoshyeilagh的化石鉴定代表了一种热带气候的环境，没有沉积的瞬间。在阿根廷、利比亚、摩洛哥、波兰和俄罗斯的沉积物中发现了一种化石，而在冈瓦纳和新devoniano地区的沉积物中发现了一种化石。由于生物相和岩石相的分析结果表明，最大衰退期是不确定的，因此，在地球上的其他地区也可能是不确定的。该地区沉积了一种生物碎屑针状砾岩-包覆岩相沉积，具有明显的生物碎屑针状砾岩-包覆岩相。本研究是一项初步的、初步的、确定有限的frasnianano - famenniano生物基础的研究，研究了形齿动物、化石、伞形动物、触手动物和介形虫。在沉积、地层、层序和全球海水沉积等方面，研究了其分布特征和解释。palavras - chae:生物相，牙形岩，有限的Frasniano-Famenniano, Neodevoniano, NE Ira。
{"title":"Biostratigraphy of the Upper Devonian Khoshyeilagh Formation in NE Iran based on conodonts and other faunas","authors":"Fatemeh Jafarbeigloo, M. Majidifard, B. Hamdi, A. Asghari, M. Arian","doi":"10.4072/RBP.2021.1.02","DOIUrl":"https://doi.org/10.4072/RBP.2021.1.02","url":null,"abstract":"The Khoshyeilagh Formation located in the northeast of Iran yielded seven conodont species and sub-species and 19 macro- and microfossil taxa that allow recognition of two conodont biozones and one biozone based on calcareous microfossils. The latest Frasnian age (the Upper rhenana to linguiformis zones) is attributed to the topmost strata with Icriodus alternatus. Its replacement with I. cornutus indicates the Famennian (Lower triangularis to Lower crepida zones) corresponding to the Umbellina Zone. The fossil assemblages identified in the Khoshyeilagh Formation represent a shallow marine environment with a tropical climate at the time of deposition. The fossil species from the Khoshyeilagh Formation and the sedimentary basins in Algeria, Libya, Morocco, Poland, and Russia reveal a close connection between the Iranian plateau and the northern parts of Gondwana in the Late Devonian. The biofacies and lithofacies analyses show a sea level decline at the end of Frasnian, followed by a considerable sea level drop, as in other regions of the world. After a short time, in the Famennian, the deepening occurred in some parts of the area and the open marine facies (bioclast spicule wackestone-packstone) were deposited. This study is the first attempt to determine Frasnian-Famennian boundary based on conodont assemblages and other fossil species such as umbellulids, tentaculites, and ostracods. The distribution of these species is interpreted in sedimentological, stratigraphic, sequence stratigraphy, and the global eustatic context.\u0000Keywords: biofacies, conodont, Frasnian-Famennian boundary, Late Devonian, NE Iran.\u0000RESUMO – A Formacao Khoshyeilagh, localizada no nordeste do Ira, produziu sete especies de conodontes e subespecies e 19 taxons de macro- e microfosseis, o que permite o reconhecimento de duas biozonas de conodontes e uma biozona baseada nos microfosseis calcareos. A idade Frasniana mais superior (as zonas superiores rhenana a linguiformis) e atribuida ao estrato mais superior com Icriodus alternatus. A sua substituicao por I. cornutus indica o Famenniano (zonas iniciais triangularis superior a crepida superior), correspondendo a Zona de Umbellina. Os fosseis identificados na Formacao Khoshyeilagh representam um ambiente marinho raso, com um clima tropical, no momento de deposicao. As especies fosseis da Formacao Khoshyeilagh e as bacias sedimentares na Argelia, Libia, Marrocos, Polonia e Russia revelam uma conexao intima entre o plato iraniano e as partes norte do Gondwana no Neodevoniano. As biofacies e litofacies analisadas mostram um declinio do nivel do mar no final do Frasniano, seguido por uma consideravel queda do nivel do mar, como em outras regioes do mundo. Apos um curto tempo, no Famenniano, o aprofundamento ocorreu em algumas partes da area, e a facies marinha aberta (bioclast spicule wackestone-packstone) foi depositada. Este estudo e a primeira tentativa de determinar o limite Frasniano-Famenniano com base em associacoes de conod","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":"24 1","pages":"21-36"},"PeriodicalIF":0.7,"publicationDate":"2021-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47641292","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}
Camila Neves Silva, Micaela Aparecida Faria Mendes, M. M. Carvalho, Gustavo Martins Stroppa
Paleontology and basic education: analysis of Parâmetros Curriculares Nacionais and textbooks in Juiz de Fora, MG, Brazil. Paleontology has a crucial role in teaching Science and Biology for helping to understand different natural processes, although there is limited space in its school approach. It is necessary to understand how its content has been worked by the teachers, both quantitatively and qualitatively. In order to understand how their themes are addressed by basic education textbooks, in private and public schools in Juiz de Fora, after analyzing the Parâmetros Curriculares Nacionais (National Curriculum Parameters, translated by the authors) - PCNs and their guidelines, from the sixth to the ninth year of elementary school and of the entire high school, a table of presence or absence was set up, with the main themes in Paleontology indicated, analyzing which were present in each book. For qualitative analysis, 11 questions were listed. The analysis included 22 themes in 18 elementary school and 15 high school books. High school books had the largest number of topics covered, with 123 presences, and elementary school, 69. The most present themes were: “Origin of Life”, “Theory of Evolution” and “Fossil Concept”; the least addressed: “Types of Fossils”, “Fossils as Non-Renewable Natural Resources” and “Great Extinctions”. Most books deal with subjects with no connection with other areas, without contextualization, with rare interdisciplinarity and relationship with environmental issues, necessary to confront science denialism and the recent risks of educational retrogression. The results reveal the importance of broadening the discussion on how to address Paleontology in basic education, assessing school incentives, teachers’ motivation, the perception of the importance of teaching this science, and the use of other tools besides the textbook. Keywords: science teaching, Base Nacional Comum Curricular, school, environmental education, fossils. RESUMO – Por auxiliar na compreensao de diversos processos naturais, a Paleontologia tem crucial papel no ensino de Ciencias e Biologia, embora haja espaco limitado em sua abordagem escolar. E preciso compreender como seu conteudo tem sido trabalhado pelos/as docentes, quantitativamente e qualitativamente. Para entender como seus temas sao abordados pelos livros didaticos do ensino basico em escolas particulares e publicas de Juiz de Fora, apos analise das diretrizes dos Parâmetros Curriculares Nacionais - PCN, do sexto ao nono ano do Ensino Fundamental e de todo o Ensino Medio, foi montada uma tabela de presenca ou ausencia, com os principais temas em Paleontologia indicados, analisando-se quais constavam em cada livro. Para analise qualitativa, foram elencadas 11 questoes. A analise abrangeu 22 temas em 18 livros do Ensino Fundamental e 15 do Ensino Medio. Os livros do Ensino Medio tiveram maior numero de temas abordados, com 123 presencas, e o Ensino Fundamental, 69. Os temas mais presentes fora
古生物学和基础教育：对巴西MG省Juiz de Fora的国家课程和教科书的分析。古生物学在科学和生物学教学中发挥着至关重要的作用，有助于理解不同的自然过程，尽管其学校方法的空间有限。有必要了解教师是如何从数量和质量上对其内容进行操作的。为了了解Juiz de Fora私立和公立学校的基础教育教科书是如何处理这些主题的，在分析了小学六至九年级和整个高中的国家课程参数及其指导方针后，建立了一个存在或不存在的表格，指出了古生物学的主要主题，并分析了每本书中存在的主题。为了进行定性分析，列出了11个问题。该分析包括18本小学和15本高中书籍中的22个主题。高中书籍涉及的主题最多，有123种，小学书籍有69种。最具代表性的主题是：“生命起源”、“进化论”和“化石概念”；涉及最少的：“化石的类型”、“化石作为不可再生的自然资源”和“大灭绝”。大多数书籍所涉及的主题与其他领域没有联系，没有背景，具有罕见的跨学科性和与环境问题的关系，这是应对科学否定和最近教育倒退风险所必需的。研究结果揭示了传播关于如何在基础教育中解决古生物学问题的讨论的重要性，评估学校激励措施、教师的动机、对教授这门科学的重要性的认识，以及使用教科书之外的其他工具。关键词：科学教学，国家通用课程基地，学校，环境教育，化石。摘要——古生物学通过帮助理解几个自然过程，在科学和生物学的教学中发挥着至关重要的作用，尽管其学校方法的空间有限。有必要了解教师是如何从数量和质量上对其内容进行操作的。为了了解Juiz de Fora私立和公立学校基础教育教材是如何处理这些主题的，在分析了国家课程参数（PCN）的指导方针后，从小学六年级到九年级以及所有高中，编制了一份出勤或缺席表，其中指出了古生物学的主要主题，分析每本书中的内容。为了进行定性分析，列出了11个问题。该分析涵盖了小学18本书和高中15本书中的22个主题。高中的书籍涉及的主题最多，有123人参加，小学为69人。最具代表性的主题是：“生命起源”、“进化论”和“化石概念”；涉及最少的是“化石类型”、“作为不可再生自然资源的化石”和“大规模灭绝”。大多数书籍处理的问题与其他领域没有联系，没有背景，具有罕见的跨学科性和与环境问题的关系，是面对科学否定主义和最近教育倒退风险所必需的。研究结果揭示了扩大关于如何在基础教育中使用古生物学的讨论的重要性，评估学校的激励措施、教师的动机、对这门科学教学主题重要性的认识，以及使用教学书籍之外的工具。关键词：科学教学，国家通用课程基地，学校，环境教育，化石。
{"title":"Paleontologia e ensino básico: análise dos Parâmetros Curriculares Nacionais e dos livros didáticos em Juiz de Fora, MG, Brasil","authors":"Camila Neves Silva, Micaela Aparecida Faria Mendes, M. M. Carvalho, Gustavo Martins Stroppa","doi":"10.4072/RBP.2021.1.05","DOIUrl":"https://doi.org/10.4072/RBP.2021.1.05","url":null,"abstract":"Paleontology and basic education: analysis of Parâmetros Curriculares Nacionais and textbooks in Juiz de Fora, MG, Brazil. Paleontology has a crucial role in teaching Science and Biology for helping to understand different natural processes, although there is limited space in its school approach. It is necessary to understand how its content has been worked by the teachers, both quantitatively and qualitatively. In order to understand how their themes are addressed by basic education textbooks, in private and public schools in Juiz de Fora, after analyzing the Parâmetros Curriculares Nacionais (National Curriculum Parameters, translated by the authors) - PCNs and their guidelines, from the sixth to the ninth year of elementary school and of the entire high school, a table of presence or absence was set up, with the main themes in Paleontology indicated, analyzing which were present in each book. For qualitative analysis, 11 questions were listed. The analysis included 22 themes in 18 elementary school and 15 high school books. High school books had the largest number of topics covered, with 123 presences, and elementary school, 69. The most present themes were: “Origin of Life”, “Theory of Evolution” and “Fossil Concept”; the least addressed: “Types of Fossils”, “Fossils as Non-Renewable Natural Resources” and “Great Extinctions”. Most books deal with subjects with no connection with other areas, without contextualization, with rare interdisciplinarity and relationship with environmental issues, necessary to confront science denialism and the recent risks of educational retrogression. The results reveal the importance of broadening the discussion on how to address Paleontology in basic education, assessing school incentives, teachers’ motivation, the perception of the importance of teaching this science, and the use of other tools besides the textbook.\u0000Keywords: science teaching, Base Nacional Comum Curricular, school, environmental education, fossils.\u0000RESUMO – Por auxiliar na compreensao de diversos processos naturais, a Paleontologia tem crucial papel no ensino de Ciencias e Biologia, embora haja espaco limitado em sua abordagem escolar. E preciso compreender como seu conteudo tem sido trabalhado pelos/as docentes, quantitativamente e qualitativamente. Para entender como seus temas sao abordados pelos livros didaticos do ensino basico em escolas particulares e publicas de Juiz de Fora, apos analise das diretrizes dos Parâmetros Curriculares Nacionais - PCN, do sexto ao nono ano do Ensino Fundamental e de todo o Ensino Medio, foi montada uma tabela de presenca ou ausencia, com os principais temas em Paleontologia indicados, analisando-se quais constavam em cada livro. Para analise qualitativa, foram elencadas 11 questoes. A analise abrangeu 22 temas em 18 livros do Ensino Fundamental e 15 do Ensino Medio. Os livros do Ensino Medio tiveram maior numero de temas abordados, com 123 presencas, e o Ensino Fundamental, 69. Os temas mais presentes fora","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":"24 1","pages":"62-69"},"PeriodicalIF":0.7,"publicationDate":"2021-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45418065","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}
J. Y. Suárez-Ibarra, G. Cardoso, Lidiane Asevedo, L. D. M. França, M. Dantas, L. E. Cruz-Guevara, Andrés Felipe Rojas-Mantilla, A. M. Ribeiro
Proboscideans arrived in South America from North America during the Great American Biotic Interchange, becoming one of the most representative animals of the megafauna thatinhabited this continent throughout the Quaternary. In Colombia, the abundance of their remains contrasts with scarce scientific descriptions and publications. This paper identifies dental and postcranial proboscidean fossils from the Center and Northeast of Colombia. The fossil remains were identified as molars (six), a tusk, cervical vertebrae, and a distal part of the right humerus. The tusk was assigned to Notiomastodon platensis, while the other remains were assigned to Gomphotheriidae, with at least six individuals: two immatures, two subadults, and two older adults–mature and senile. Keywords: South America, megamammals, taxonomy, Gomphotheriidae, Notiomastodon platensis.
{"title":"Quaternary proboscidean (Mammalia) remains of the UIS Geological Museum, Colombia","authors":"J. Y. Suárez-Ibarra, G. Cardoso, Lidiane Asevedo, L. D. M. França, M. Dantas, L. E. Cruz-Guevara, Andrés Felipe Rojas-Mantilla, A. M. Ribeiro","doi":"10.4072/RBP.2021.1.06","DOIUrl":"https://doi.org/10.4072/RBP.2021.1.06","url":null,"abstract":"Proboscideans arrived in South America from North America during the Great American Biotic Interchange, becoming one of the most representative animals of the megafauna thatinhabited this continent throughout the Quaternary. In Colombia, the abundance of their remains contrasts with scarce scientific descriptions and publications. This paper identifies dental and postcranial proboscidean fossils from the Center and Northeast of Colombia. The fossil remains were identified as molars (six), a tusk, cervical vertebrae, and a distal part of the right humerus. The tusk was assigned to Notiomastodon platensis, while the other remains were assigned to Gomphotheriidae, with at least six individuals: two immatures, two subadults, and two older adults–mature and senile.\u0000Keywords: South America, megamammals, taxonomy, Gomphotheriidae, Notiomastodon platensis.","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":"24 1","pages":"70-75"},"PeriodicalIF":0.7,"publicationDate":"2021-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47313120","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}
João da Fonseca Gomes de Lemos, Geize Carolinne Correia Andrade Oliveira
Calcareous nannofossils of the Lower Tejo Basin Miocene, Portugal. This study presents the taxonomy, biostratigraphy, and paleoecology of calcareous nannofossils from an outcrop on the border of Foz da Fonte beach, geologically setting in the Neogene of the Lower Tejo Basin, Portugal. The taxonomic description allowed us to identify 19 calcareous nannofossils species belonging to ten genera (Helicosphaera, Pontosphaera, Reticulofenestra, Cyclicargolithus, Coccolithus, Discoaster, Sphenolithus, Umbilicosphaera, Calcidiscus, and Thoracosphaera). Based on the stratigraphic range of Discoaster druggii, Reticulofenestra lockeri and Helicosphaera ampliaperta the section was defined in the NN2 and CN1 biozones, within the Burdigalian (lower Miocene). Quantitative analysis showed a significant variation in species diversity as a function of depth, as well as a relationship between species richness and the calcium carbonate content present in these rocks. According to these data, mainly due to the abundance of Reticulofenestra spp., Coccolithus spp. and Helicosphaera spp., it is possible to infer that this was a nutrient-rich nearshore marine environment (eutrophic) influenced by warm water conditions. Keywords: calcareous nannofossils, taxonomy, biostratigraphy, paleoecology, Neogene, Lower Tejo Basin. RESUMO – Este estudo apresenta a taxonomia, bioestratigrafia e paleoecologia dos nanofosseis calcarios presentes nas rochas que afloram as margens da praia da Foz da Fonte, geologicamente pertencentes ao Neogeno da Bacia do Baixo Tejo, Portugal. A descricao taxonomica permitiu identificar 19 especies de nanofosseis calcarios pertencentes a dez generos (Helicosphaera, Pontosphaera, Reticulofenestra, Cyclicargolithus, Coccolithus, Discoaster, Sphenolithus, Umbilicosphaera, Calcidiscus e Thoracosphaera). Com base na distribuicao bioestratigrafica de Discoaster druggii, Reticulofenestra lockeri e Helicosphaera ampliaperta a secao foi definida pertencendo as biozonas NN2 e CN1, dentro do Burdigaliano (Mioceno inferior). A analise quantitativa mostrou significativa variacao na diversidade de especies em funcao da profundidade e, tambem, uma relacao entre a riqueza especifica e abundância com o teor de carbonato de calcio presente nas rochas. De acordo com esses dados, principalmente pela abundância de Reticulofenestra spp., Coccolithus spp. e Helicosphaera spp. e possivel inferir que tratava de um ambiente marinho proximo a costa, rico em nutrientes (eutrofico), influenciado por massas de aguas quentes. Palavras-chave: nanofosseis calcarios, taxonomia, bioestratigrafia, paleoecologia, Neogeno, Bacia do Baixo Tejo.
葡萄牙下特茹盆地中新世的钙质超微化石。本研究介绍了葡萄牙下特霍盆地新近系Foz da Fonte海滩边界露头的钙质超微化石的分类学、生物地层学和古生态学。分类描述使我们能够鉴定出19种钙质超微化石，隶属于10个属（Helicosphaera、Ponthopaera、Reticulfenestra、Cycicargolithus、Coccolithus、Discoaster、Sphenolithus、Umbilicophaera、Calcidesis和Thoracophaera）。根据Discoaster drugii、Reticulfenestra lockeri和Helicosphaera magnifaperta的地层范围，该剖面被定义在Burdigalian（下中新世）内的NN2和CN1生物带中。定量分析显示，物种多样性随着深度的变化而发生显著变化，物种丰富度与这些岩石中碳酸钙含量之间也存在关系。根据这些数据，主要由于网织开窗菌属、Coccolithus属和Helicosphaera属的丰度，可以推断这是一个受温水条件影响的营养丰富的近岸海洋环境（富营养化）。关键词：钙质纳米化石，分类学，生物地层学，古生态学，新近纪，下特茹盆地摘要——本研究介绍了在Foz da Fonte海滩海岸露头的岩石中存在的钙质纳米化石的分类学、生物地层学和古生态学，在地质学上属于葡萄牙Baixo-Tejo盆地的新近纪。分类描述允许鉴定出19种钙质纳米化石，属于10个大类（Helicosphaera、Pontosphaera，Reticulfenestra，Cycicargolithus，Coccolithus，Discoaster，Sphenolithus，Umbilichosphaera）。根据Discoaster drugii、Reticulfenestra lockeri和Helicosphaera amplifaperta的生物地层学分布，该剖面被定义为属于Burdigalian（下Myocene）内的NN2和CN1生物带。定量分析显示，物种多样性随着深度的变化而发生显著变化，特定丰富度和丰度与岩石中碳酸钙含量之间也存在关系。根据这些数据，主要是由于网状开窗菌属、Coccolithus属和Helicosphaera属的丰度，可以推断这是一个靠近海岸的海洋环境，富含营养物质（富营养化），受到热水团的影响。关键词：钙质纳米化石，分类学，生物地层学，古生态学，新近纪，拜克索特霍盆地。
{"title":"Nanofósseis calcários do Mioceno da Bacia do Baixo Tejo, Portugal","authors":"João da Fonseca Gomes de Lemos, Geize Carolinne Correia Andrade Oliveira","doi":"10.4072/RBP.2021.1.04","DOIUrl":"https://doi.org/10.4072/RBP.2021.1.04","url":null,"abstract":"Calcareous nannofossils of the Lower Tejo Basin Miocene, Portugal. This study presents the taxonomy, biostratigraphy, and paleoecology of calcareous nannofossils from an outcrop on the border of Foz da Fonte beach, geologically setting in the Neogene of the Lower Tejo Basin, Portugal. The taxonomic description allowed us to identify 19 calcareous nannofossils species belonging to ten genera (Helicosphaera, Pontosphaera, Reticulofenestra, Cyclicargolithus, Coccolithus, Discoaster, Sphenolithus, Umbilicosphaera, Calcidiscus, and Thoracosphaera). Based on the stratigraphic range of Discoaster druggii, Reticulofenestra lockeri and Helicosphaera ampliaperta the section was defined in the NN2 and CN1 biozones, within the Burdigalian (lower Miocene). Quantitative analysis showed a significant variation in species diversity as a function of depth, as well as a relationship between species richness and the calcium carbonate content present in these rocks. According to these data, mainly due to the abundance of Reticulofenestra spp., Coccolithus spp. and Helicosphaera spp., it is possible to infer that this was a nutrient-rich nearshore marine environment (eutrophic) influenced by warm water conditions.\u0000Keywords: calcareous nannofossils, taxonomy, biostratigraphy, paleoecology, Neogene, Lower Tejo Basin.\u0000RESUMO – Este estudo apresenta a taxonomia, bioestratigrafia e paleoecologia dos nanofosseis calcarios presentes nas rochas que afloram as margens da praia da Foz da Fonte, geologicamente pertencentes ao Neogeno da Bacia do Baixo Tejo, Portugal. A descricao taxonomica permitiu identificar 19 especies de nanofosseis calcarios pertencentes a dez generos (Helicosphaera, Pontosphaera, Reticulofenestra, Cyclicargolithus, Coccolithus, Discoaster, Sphenolithus, Umbilicosphaera, Calcidiscus e Thoracosphaera). Com base na distribuicao bioestratigrafica de Discoaster druggii, Reticulofenestra lockeri e Helicosphaera ampliaperta a secao foi definida pertencendo as biozonas NN2 e CN1, dentro do Burdigaliano (Mioceno inferior). A analise quantitativa mostrou significativa variacao na diversidade de especies em funcao da profundidade e, tambem, uma relacao entre a riqueza especifica e abundância com o teor de carbonato de calcio presente nas rochas. De acordo com esses dados, principalmente pela abundância de Reticulofenestra spp., Coccolithus spp. e Helicosphaera spp. e possivel inferir que tratava de um ambiente marinho proximo a costa, rico em nutrientes (eutrofico), influenciado por massas de aguas quentes.\u0000Palavras-chave: nanofosseis calcarios, taxonomia, bioestratigrafia, paleoecologia, Neogeno, Bacia do Baixo Tejo.","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":"24 1","pages":"47-61"},"PeriodicalIF":0.7,"publicationDate":"2021-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45112119","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}
A. M. Siegloch, M. Guerra-Sommer, C. Schultz, E. Barboza
The goals of this study were to establish patterns in a silicified wood assemblage to depict the evolution patterns of the Triassic paleoclimate in southern Brazilian Gondwana during an interval of global arid to semi-arid climatic context, and the taphonomic process that led to the preservation of the so-called “Petrified Forest”, which is preserved in the central area of the state of Rio Grande do Sul. Analyses were developed with an assemblage of 13 permineralized conifer wood, using standard thin sections, whose anatomical details were studied in transmitted light. Ground-Penetrating Radar was used to obtain information about the depositional characteristics of the site. Main results are: true growth rings are absent in all samples, and the boundaries of the interruption zones are marked by an abrupt decline in cell diameter, but they are not accompanied by a reduction of cell wall thickness. The subsequent reversion to normal tracheid diameter is also abrupt, revealing the return of the previous growing conditions. Ground-penetrating Radar analyses confirmed that the Mata Sequence deposits correspond to a river. The identification of growth interruption zones in a Late Triassic wood assemblage in southernmost Brazilian Gondwana (Paleobotanic Garden of the city of Mata, RS) indicates the presence of tropical, temporarily dry climate conditions, characterized by irregular, short-term environmental disturbances to growth. The taphonomic process was related to a river-channel infilling depositional process, under the influence of high-energy flood events that dragged and buried the trees. Keywords: Wood growth patterns, Mata sequence, gymnosperms, Triassic climate, petrified forest. RESUMO – O objetivo do presente trabalho foi obter assinaturas climaticas por meio da analise de padroes de crescimento em uma associacao de lenhos silicificados a fim de retratar os padroes de evolucao do paleoclima no Triassico no Gondwana sul-brasileiro durante um intervalo de condicoes climaticas globais aridas-semiaridas e esclarecer o contexto sedimentar e o processo tafonomico relacionado a preservacao da “Floresta Petrificada”, preservada na area central do Estado do Rio Grande do Sul. Secoes delgadas foram elaboradas a partir de 13 amostras de lenhos permineralizados, sendo os detalhes anatomicos estudados em microscopia optica sob luz transmitida. A tecnica de Penetracao do Solo por Radar (Ground Penetrating Radar - GPR) foi utilizada para obter informacoes sobre as caracteristicas deposicionais. Os principais resultados foram: ausencia de verdadeiros aneis de crescimento nas amostras e todos os especimes sao caracterizados por interrupcoes de crescimento concentricas. Os limites das zonas de interrupcao sao marcados por um declinio abrupto no diâmetro da celula, mas nao sao acompanhados por uma reducao da espessura da parede celular. A reversao subsequente para o diâmetro traqueideo normal tambem e abrupta, revelando o retorno das condicoes de crescimento
本研究的目的是在硅化木组合中建立模式，以描述全球干旱至半干旱气候背景下巴西冈瓦纳南部三叠纪古气候的演化模式，以及导致所谓的“石化森林”得以保存的地学过程，该地学过程保存在巴西南里约热内卢格兰德州中部地区。使用标准薄片对13种过矿化针叶树木材进行了分析，并在透射光下研究了其解剖细节。利用探地雷达获得有关该地点沉积特征的信息。主要结果是:在所有样品中都没有真正的生长环，并且中断区的边界以细胞直径的突然下降为标志，但它们并不伴随着细胞壁厚度的减少。随后向正常气管直径的恢复也是突然的，显示了先前生长条件的恢复。探地雷达分析证实，玛塔层序沉积物对应于一条河流。巴西冈瓦纳最南端(马塔市古植物园)晚三叠世木材组合中生长中断带的确定表明存在热带，暂时干燥的气候条件，其特征是不规则的，短期环境干扰生长。埋藏过程与河道淤积过程有关，是在高能量洪水事件的影响下，将树木拖拽掩埋的。关键词:木材生长模式，Mata序列，裸子植物，三叠纪气候，石化林摘要:目的:为研究不同地区的自然气候变化提供参考，分析不同地区的自然气候变化，分析不同地区的自然气候变化，分析不同地区的自然气候变化，分析不同地区的自然气候变化，分析不同地区的古气候变化，分析不同地区的古气候变化，分析不同地区的古气候变化，分析不同地区的古气候变化，分析不同地区的古气候变化，分析不同地区的全球气候变化，分析不同地区的气候变化，分析不同地区的沉积过程，分析不同地区的沉积过程，分析不同地区的沉积过程，分析不同地区的沉积过程，分析不同地区的沉积过程，分析不同地区的沉积过程。从解剖角度看，解剖角度看，解剖角度看，透视角度看，透视角度看，透视角度看，透视角度看，透视角度看。探地雷达(GPR)技术是一种利用地层特征等参数信息进行探测的技术。其主要成果是:从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看，从纵向上看。因此，在细胞发育过程中，当细胞发育过程中出现异常现象时，就会出现异常现象。一个反向的随后的para, di metro traquedeo正常的tambebee突然发生，揭示了在前渐行渐近的条件下，反向的条件。根据地质探地雷达的分析，确定了地质层序中沉积物的特征，并对加拿大河流的预防进行了相应的澄清。一个相同的区域，从中断区到渐变区，从渐变区到渐变区，从渐变区到渐变区，从渐变区到渐变区，从渐变区到渐变区，从渐变区到渐变区，从渐变区到渐变区，从渐变区到渐变区，再到渐变区。一个历史经济学家认为，加拿大河流预防过程的关系，即洪水的影响，即能源的影响，即河流的影响，即河流的影响，即河流的影响。植物:生长中断带、Mata序列、裸子植物、三叠纪植物、石化花。
{"title":"Paleoclimatic inferences based on wood growth interruptions in Late Triassic flood deposits from the southernmost Brazilian Gondwana","authors":"A. M. Siegloch, M. Guerra-Sommer, C. Schultz, E. Barboza","doi":"10.4072/RBP.2021.1.01","DOIUrl":"https://doi.org/10.4072/RBP.2021.1.01","url":null,"abstract":"The goals of this study were to establish patterns in a silicified wood assemblage to depict the evolution patterns of the Triassic paleoclimate in southern Brazilian Gondwana during an interval of global arid to semi-arid climatic context, and the taphonomic process that led to the preservation of the so-called “Petrified Forest”, which is preserved in the central area of the state of Rio Grande do Sul. Analyses were developed with an assemblage of 13 permineralized conifer wood, using standard thin sections, whose anatomical details were studied in transmitted light. Ground-Penetrating Radar was used to obtain information about the depositional characteristics of the site. Main results are: true growth rings are absent in all samples, and the boundaries of the interruption zones are marked by an abrupt decline in cell diameter, but they are not accompanied by a reduction of cell wall thickness. The subsequent reversion to normal tracheid diameter is also abrupt, revealing the return of the previous growing conditions. Ground-penetrating Radar analyses confirmed that the Mata Sequence deposits correspond to a river. The identification of growth interruption zones in a Late Triassic wood assemblage in southernmost Brazilian Gondwana (Paleobotanic Garden of the city of Mata, RS) indicates the presence of tropical, temporarily dry climate conditions, characterized by irregular, short-term environmental disturbances to growth. The taphonomic process was related to a river-channel infilling depositional process, under the influence of high-energy flood events that dragged and buried the trees.\u0000Keywords: Wood growth patterns, Mata sequence, gymnosperms, Triassic climate, petrified forest.\u0000RESUMO – O objetivo do presente trabalho foi obter assinaturas climaticas por meio da analise de padroes de crescimento em uma associacao de lenhos silicificados a fim de retratar os padroes de evolucao do paleoclima no Triassico no Gondwana sul-brasileiro durante um intervalo de condicoes climaticas globais aridas-semiaridas e esclarecer o contexto sedimentar e o processo tafonomico relacionado a preservacao da “Floresta Petrificada”, preservada na area central do Estado do Rio Grande do Sul. Secoes delgadas foram elaboradas a partir de 13 amostras de lenhos permineralizados, sendo os detalhes anatomicos estudados em microscopia optica sob luz transmitida. A tecnica de Penetracao do Solo por Radar (Ground Penetrating Radar - GPR) foi utilizada para obter informacoes sobre as caracteristicas deposicionais. Os principais resultados foram: ausencia de verdadeiros aneis de crescimento nas amostras e todos os especimes sao caracterizados por interrupcoes de crescimento concentricas. Os limites das zonas de interrupcao sao marcados por um declinio abrupto no diâmetro da celula, mas nao sao acompanhados por uma reducao da espessura da parede celular. A reversao subsequente para o diâmetro traqueideo normal tambem e abrupta, revelando o retorno das condicoes de crescimento ","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":"24 1","pages":"3-20"},"PeriodicalIF":0.7,"publicationDate":"2021-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47100028","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}
A robust biostratigraphic zonation based on microfossils supports the stratigraphic framework and correlation of the interior basins of the Lower Cretaceous of NE Brazil. This zonation has also allowed correlations with coeval sections in the Brazilian marginal basins and in the Gabon and Congo basins (central-west Africa). These records, consisting mainly of non-marine sediments, were a great challenge with regard to the correlation with the International Chronostratigraphic Chart. Therefore, local stages were used, the most recent being the Alagoas local Brazilian Stage, with which the Post-rift Sequence I of the Araripe Basin is related. Regarding lithostratigraphy, this sequence includes the Rio da Batateira (Barbalha for some authors) and Santana formations, the last one with the famous Crato, Ipubi, and Romualdo members, from the base to the top. Although currently there is a consensus on the age of the Alagoas local Brazilian Stage in the Araripe Basin, recently a new age for at least part of the Post-rift Sequence I was proposed. This new proposal, based on isotopic analysis of Re-Os, arose as a panacea to correlate the Rio da Batateira Formation and the Crato and Ipubi members with the international stages. Surprisingly, their authors, although on the one hand, they seem to underestimate biostratigraphic results, on the other they seek to support their proposal from microfossils studied by previous authors, but they do so in an inappropriate way, leading readers to misinterpret their results. Therefore, this paper presents a critical review on the age of the Alagoas local Brazilian Stage in the Araripe Basin and nearby basins, refuting a Barremian age for part of the Post-rift Sequence I. Keywords: Alagoas local Brazilian Stage, biostratigraphy, ostracods, palynomorphs, radiometric ages. RESUMO – Um robusto zoneamento bioestratigrafico baseado em microfosseis suporta o arcabouco estratigrafico e a correlacao dos estratos eocretaceos das bacias interiores do NE do Brasil. Esse zoneamento permite tambem correlacoes com secoes coevas nas bacias marginais brasileiras e nas bacias do Gabao e Congo (centro-oeste da Africa). Tais registros, compostos principalmente por sedimentos nao-marinhos, foram um grande desafio em termos de correlacao com a Tabela Cronoestratigrafica Internacional. Assim, foram empregados andares locais, sendo o estratigraficamente mais alto o Andar Alagoas, com o qual a Sequencia Pos-rifte I da Bacia do Araripe esta relacionada. Quanto a litoestratigrafia, essa sequencia inclui as formacoes Rio da Batateira (Barbalha para alguns autores) e Santana, a qual esta subdividida nos famosos membros Crato, Ipubi e Romualdo, da base para o topo. Embora atualmente haja consenso sobre a idade do Andar Alagoas naBacia do Araripe, recentemente foi proposta uma nova idade para parte da Sequencia Pos-rifte I. Essa nova proposta, baseada em analises isotopicas de Re-Os, foi apresentada como uma panaceia para correlacionar a formacao Rio
基于微化石的强有力的生物地层学分带支持了巴西东北部下白垩统内部盆地的地层格架和对比。这种分带也允许与巴西边缘盆地和加蓬和刚果盆地(中非西部)的同期剖面进行对比。这些记录主要由非海相沉积物组成，在与国际年代地层图的对比方面是一个巨大的挑战。因此，采用局部阶段，最近的是阿拉戈斯局部巴西阶段，与Araripe盆地的后裂谷层序I有关。在岩石地层方面，该层序从底部到顶部包括里约热内卢da Batateira(有些作者称之为Barbalha)和Santana组，最后是著名的Crato、Ipubi和Romualdo组。尽管目前对于Araripe盆地的Alagoas当地巴西阶段的年龄已经达成共识，但最近提出了至少部分后裂谷层序I的新时代。这一基于Re-Os同位素分析的新建议，作为将bbb100 da Batateira组和Crato和Ipubi成员与国际舞台联系起来的灵丹妙药。令人惊讶的是，他们的作者一方面似乎低估了生物地层学的结果，另一方面又试图从前人研究过的微化石中寻求支持，但他们这样做的方式不恰当，导致读者误解了他们的结果。因此，本文对Araripe盆地及附近盆地的Alagoas局部巴西阶段的年龄进行了批判性的回顾，反驳了部分后裂谷层序i的巴雷米亚时代。关键词:Alagoas局部巴西阶段，生物地层学，介形类，岩形，辐射年龄。在巴西东北地区，利用微化石支持的arcabouco地层特征，建立了一套完整的生物地层特征带，并与e白垩纪地层和bacias interioes地层进行了对比。区域修正案允许各地区的相关人员，如巴西边缘地区、刚果中部地区和刚果中部地区的相关人员。这些记录，主要的复合材料，主要的沉积物，主要的海洋沉积物，有孔层和大的地层分析，以及相关的术语，国际地层表。阿西姆，形成了empregados和ares locais，在安达拉戈亚斯的主要地区进行了地层划分，并与“后地层序列”和“盆地与地区关系”相一致。该序列包括Barbalha para alguns autores (Barbalha para alguns autores)和Santana (Santana)，是著名成员Crato, Ipubi和Romualdo的一个相同的分支，数据库基础para to topo。最近的一项研究表明，最近的一项研究表明，在新发现的基础上，对Re-Os的同位素进行了基础分析，在新发现的基础上，对新发现的同位素进行了分析，并在新发现的基础上，对新发现的同位素进行了对比分析，并在新发现的基础上，对新发现的同位素进行了对比分析。观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，解释，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察，观察。研究:安达拉戈亚斯，生物地层学，介形虫，白斑虫，放射学，生物地层学。
{"title":"Age of the Post-rift Sequence I from the Araripe Basin, Lower Cretaceous, NE Brazil: implications for spatio-temporal correlation","authors":"J. Coimbra, Tiago Freire","doi":"10.4072/RBP.2021.1.03","DOIUrl":"https://doi.org/10.4072/RBP.2021.1.03","url":null,"abstract":"A robust biostratigraphic zonation based on microfossils supports the stratigraphic framework and correlation of the interior basins of the Lower Cretaceous of NE Brazil. This zonation has also allowed correlations with coeval sections in the Brazilian marginal basins and in the Gabon and Congo basins (central-west Africa). These records, consisting mainly of non-marine sediments, were a great challenge with regard to the correlation with the International Chronostratigraphic Chart. Therefore, local stages were used, the most recent being the Alagoas local Brazilian Stage, with which the Post-rift Sequence I of the Araripe Basin is related. Regarding lithostratigraphy, this sequence includes the Rio da Batateira (Barbalha for some authors) and Santana formations, the last one with the famous Crato, Ipubi, and Romualdo members, from the base to the top. Although currently there is a consensus on the age of the Alagoas local Brazilian Stage in the Araripe Basin, recently a new age for at least part of the Post-rift Sequence I was proposed. This new proposal, based on isotopic analysis of Re-Os, arose as a panacea to correlate the Rio da Batateira Formation and the Crato and Ipubi members with the international stages. Surprisingly, their authors, although on the one hand, they seem to underestimate biostratigraphic results, on the other they seek to support their proposal from microfossils studied by previous authors, but they do so in an inappropriate way, leading readers to misinterpret their results. Therefore, this paper presents a critical review on the age of the Alagoas local Brazilian Stage in the Araripe Basin and nearby basins, refuting a Barremian age for part of the Post-rift Sequence I.\u0000Keywords: Alagoas local Brazilian Stage, biostratigraphy, ostracods, palynomorphs, radiometric ages.\u0000RESUMO – Um robusto zoneamento bioestratigrafico baseado em microfosseis suporta o arcabouco estratigrafico e a correlacao dos estratos eocretaceos das bacias interiores do NE do Brasil. Esse zoneamento permite tambem correlacoes com secoes coevas nas bacias marginais brasileiras e nas bacias do Gabao e Congo (centro-oeste da Africa). Tais registros, compostos principalmente por sedimentos nao-marinhos, foram um grande desafio em termos de correlacao com a Tabela Cronoestratigrafica Internacional. Assim, foram empregados andares locais, sendo o estratigraficamente mais alto o Andar Alagoas, com o qual a Sequencia Pos-rifte I da Bacia do Araripe esta relacionada. Quanto a litoestratigrafia, essa sequencia inclui as formacoes Rio da Batateira (Barbalha para alguns autores) e Santana, a qual esta subdividida nos famosos membros Crato, Ipubi e Romualdo, da base para o topo. Embora atualmente haja consenso sobre a idade do Andar Alagoas naBacia do Araripe, recentemente foi proposta uma nova idade para parte da Sequencia Pos-rifte I. Essa nova proposta, baseada em analises isotopicas de Re-Os, foi apresentada como uma panaceia para correlacionar a formacao Rio","PeriodicalId":49616,"journal":{"name":"Revista Brasileira De Paleontologia","volume":"24 1","pages":"37-46"},"PeriodicalIF":0.7,"publicationDate":"2021-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46402013","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}
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