Papers by Robbyson M Melo
Bookmarks Related papers MentionsView impact
Cretaceous Research
Bookmarks Related papers MentionsView impact
Cretaceous Research, 2021
Abstract A biostratigraphic and paleoenvironmental characterization of the Campanian–Maastrichtia... more Abstract A biostratigraphic and paleoenvironmental characterization of the Campanian–Maastrichtian deposits on The Naze (James Ross Island, Antarctica) based on the foraminiferal assemblages, lithofacies analysis, and Hg/total organic carbon (TOC) data was developed. The sedimentary deposits mapped in The Naze region showed an association of four sedimentary lithofacies, including greenish-gray claystone, shales with levels of concretion, bioturbated marl, and sandstone. The sedimentary deposits have been covered by a fifth lithofacies, the James Ross Island Volcanic Group (JRIVG), which consists of pyroclastic rocks interbedded with basalt bodies. The association of agglutinated foraminifera was found to consist mainly of Rzehakina epigona, Trochammina ribstonensis, Gaudryina healyi, Karreriella aegra, Dorothia elongata, Alveolophragmium macellarii, Cyclammina complanata and Spiroplectammina spectabilis, that allow to infer a Campanian–early Maastrichtian age to the studied interval. An association of opportunistic agglutinated foraminifera predominated in this stressful environment. The absence of Hg-TOC unassociated excursions ruled out distal volcanism as a source of environmental stress, while Hg/TOC ratio variability suggested that regional oceanic processes were the major environmental change driver.
Bookmarks Related papers MentionsView impact
Revista de …, 2010
Bookmarks Related papers MentionsView impact
Este trabalho apresenta as ocorrencias de mamiferos quaternarios no noroeste do Estado do Ceara, ... more Este trabalho apresenta as ocorrencias de mamiferos quaternarios no noroeste do Estado do Ceara, bem como um diagnostico desta mastofauna, a partir de informacoes cientificas e dados informais que foram checados in loco . A investigacao bibliografica foi baseada em artigos cientificos, jornais locais e literatura geral, no intuito de encontrar registros paleontologicos. Constatou-se entao, a escassez de publicacoes cientificas sobre o assunto na area estudada. A maior parte dos dados de ocorrencias fossiliferas era informal e incompleto, por isso foram feitas visitas de reconhecimento aos locais citados para checar a veracidade das informacoes. Nessa regiao, mamiferos fosseis ocorrem em dois tipos de depositos quaternarios: tanques e cavernas. Com os dados obtidos confeccionou-se um mapa, onde foram pontuadas oito localidades em quatro municipios do noroeste do Ceara: Mucambo, Santa Quiteria, Sobral e Ubajara. Foram registradas as seguintes familias: Felidae, Glyptodontidae, Gompho...
Bookmarks Related papers MentionsView impact
Cretaceous Research, 2021
Bookmarks Related papers MentionsView impact
Gondwana Research
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Brazilian Journal of Geology
Bookmarks Related papers MentionsView impact
Brazilian Journal of Geology, 2023
Benthic foraminifera, ostracods and pteropods are reliable paleoenvironmental indicators in Quate... more Benthic foraminifera, ostracods and pteropods are reliable paleoenvironmental indicators in Quaternary deposits. However, in the Ceará Basin, on the Brazilian Equatorial Margin, these microfossils are poorly studied. This paper investigates environmental changes during the Pleistocene-Holocene transition in the Icaraí subbasin based on micropaleontological analysis of the core ANP 1011. Seventy-four taxa of benthic foraminifera, represented predominantly by Globocassidulina, Uvigerina, Pyrgo and Melonis, have been identified. The ostracod assemblages are composed mainly by the families Macrocyprididae, Cytheruridae, Trachyleberididae, Pontocyprididae and Krithidae, of which the genus Krithe was the most abundant. The composition of the ostracod assemblages identified in this study area differs somewhat from other regions of the Brazilian Margin. The assemblages of foraminifera and ostracod characterize a typical bathyal paleoenvironment. The occurrence of pteropods and dominance of epifaunal foraminifera taxa, mainly Pyrgo sp. and Miliolinella sp. in the lower portion of the core (Pleistocene), indicates higher phytodetritus input and oxygen concentration. A conspicuous environmental change was observed in the upper portion of the core, which corresponds to the Holocene, where the increase of infaunal foraminifera (e.g., Uvigerina, Globocassidulina and Melonis) suggests reduction in the organic matter input and, probably, increased bacterial density and depletion in dissolved oxygen in the sediment.
Bookmarks Related papers MentionsView impact
Estudos Geológicos, 2020
The ANP 1040 core analyzed was collected at a depth of 1900 m in the Equatorial Atlantic Ocean, a... more The ANP 1040 core analyzed was collected at a depth of 1900 m in the Equatorial Atlantic Ocean, around 100.8 km from the coastline of the municipality of Itapipoca, Ceará. Particle size analyzes, geochemistry by X-ray fluorescence, calcium carbonate, organic matter and total nitrogen contents were performed. The data show that the ANP 1040 core contains the mud, sandy mud and muddy facies, composed of bioclastic sediments classified as limestone. The decrease of the marine influence on the sedimentation was observed in the intermediate interval of the core because it presented high levels of Ti/Ca and Fe/Ca ratios. In addition, this interval was correlated to high values of mud, organic matter, and low percentage of carbonate content. The high values of these ratios (Ti/Ca and Fe/Ca) are related to an increase of the continental sedimentary contribution, denoting a period of a greater precipitation in the region, indicating a humid tropical climate that increased the flow of the con...
Bookmarks Related papers MentionsView impact
Revista Brasileira de Paleontologia, 2021
This research addresses paleoclimatic variations using sedimentological, geochemical, and plankti... more This research addresses paleoclimatic variations using sedimentological, geochemical, and planktic foraminifera. The study was carried out in a survey core (ANP 1011) collected on the continental slope of the Icaraí Sub-basin (Ceará Basin), on the coast of the Municipality of Itapipoca, CE, Brazil. Particle size analysis, CaCO3 content, Ti/Ca and Fe/Ca ratios, and the analysis of foraminifera associations for biostratigraphic purposes were performed. Based on the relative abundance of planktic foraminifera, with indicators of warm and cold water throughout the studied cores, two biozones (Y: Upper Pleistocene and Z: Holocene), and two subzones (Z2 and Z1) were recognized. The data of sedimentological markers obtained confirmed the occurrence of more wet phases in northeastern Brazil during the early stages of the Holocene. The Ti/Ca and Fe/Ca ratios, as well as the geochemical and micropaleontological proxies, indicated a farther north displacement of the Intertropical Convergence Z...
Bookmarks Related papers MentionsView impact
This study shows foraminifera and ostracods recovered in a sampling from the Cotinguiba Formation... more This study shows foraminifera and ostracods recovered in a sampling from the Cotinguiba Formation, SergipeAlagoas Basin. The ostracoda microfauna is compound by an abundance of Paracypris eniotmetos (Candonidae) and trachyleberidids (Sergipella? sp., Sapucariella multidifferentis e Sapucariella sp.), besides of taxa Cytherella gambiensis and Cytherelloidea sp., belonging to the Cytherellidae family. The benthic foraminifera association is compound by agglutinant taxa with predominance of the spiroplectamminids (Quasispiroplectammina cf. regoi and Quasispiroplectammina sp.), and taxa with calcareous hyaline shells, represented by gavelinelids and turrinilids (genus Praebulimina), which domain the association. The planktonic foraminifera assemblage is recognized by the frequency of Planoheterohelix ex gr. Globulosa and abundant hedbergenilids, represented by the genus Whiteinella (Whiteinella baltica, Whiteinella cf. baltica, Whiteinella aff. archaeocretacea, Whiteinella? sp.), beside...
Bookmarks Related papers MentionsView impact
Revue de Micropaléontologie
Bookmarks Related papers MentionsView impact
The aim of paleontology is the understanding of the life history on Earth, its development and pr... more The aim of paleontology is the understanding of the life history on Earth, its development and processes along the geologic time. Hence, it involves diversified fields, being the micropaleontology one of them, whose focus lies on taxonomy and applications. The micropaleontology is, sometimes, poorly developed in an institution due to the scarcity of specialists. In order to fill this gap, a didactic collection was prepared to facilitate the divulgation of the micropaleontology in the university. Due to the necessity of increase in the knowledge on microfossils among graduate and undergraduate students, an extension project of microfossils didactic collection was carried out at the Geology Department of the Universidade Federal de Pernambuco. For each fossil group (i.e. ostracods, foraminifers, calcareous nannofossils, charophytes, radiolarians, diatoms, conodonts, palynomorphs, fish fragments, echinoid spines, sponge spicules and mollusks) micropaleontological slides were assembled....
Bookmarks Related papers MentionsView impact
Terrae Didatica, Nov 30, 2018
Bookmarks Related papers MentionsView impact
Terrae Didatica, 2018
The aim of paleontology is the understanding of the life history on Earth, its development and pr... more The aim of paleontology is the understanding of the life history on Earth, its development and processes along the geologic time. Hence, it involves diversified fields, being the micropaleontology one of them, whose focus lies on taxonomy and applications. The micropaleontology is, sometimes, poorly developed in an institution due to the scarcity of specialists. In order to fill this gap, a didactic collection was prepared to facilitate the divulgation of the micropaleontology in the university. Due
to the necessity of increase in the knowledge on microfossils among graduate and undergraduate students, an extension project of microfossils didactic collection was carried out at the Geology
Department of the Universidade Federal de Pernambuco. For each fossil group (i.e. ostracods, foraminifers, calcareous nannofossils, charophytes, radiolarians, diatoms, conodonts, palynomorphs, fish fragments, echinoid spines, sponge spicules and mollusks) micropaleontological slides were assembled. The origin of the material is varied, with specimens from several Brazilian sedimentary basins and even from other countries. The collections consist in numbered and identified slides, besides the material necessary for their manipulation, such as brushes and spare slides. In each fossil group, the specimens are organized according to the morphology, taxonomy and age. Each slide has instructions for classes inserted in a Guidebook of micropaleontology thoroughly illustrated, with general characteristics of each fossil group and the respective methodology for sample preparation. The collection is intended to be used in practical classes, workshops and short-courses, with biological, petrographic and stereoscopic microscopes, for observation of the morphological structures, identification and solution of problems proposed in the guidebook. Besides the improvement in the paleontology teaching, these collections will also contribute to the qualification of the students as
future professionals.
Bookmarks Related papers MentionsView impact
Revista Geociências, 2019
This study shows foraminifera and ostracods recovered in a sampling from the Cotinguiba Formation... more This study shows foraminifera and ostracods recovered in a sampling from the Cotinguiba Formation, Sergipe-Alagoas Basin. The ostracoda microfauna is compound by an abundance of Paracypris eniotmetos (Candonidae) and trachyleberidids (Sergipella? sp., Sapucariella multidifferentis e Sapucariella sp.), besides of taxa Cytherella gambiensis and Cytherelloidea sp., belonging to the Cytherellidae family. The benthic foraminifera association is compound by agglutinant taxa with predominance of the spiroplectamminids (Quasispiroplectammina cf. regoi and Quasispiroplectammina sp.), and taxa with calcareous hyaline shells, represented by gavelinelids and turrinilids (genus Praebulimina), which domain the association. The planktonic foraminifera assemblage is recognized by the frequency of Planoheterohelix ex gr. Globulosa and abundant hedbergenilids, represented by the genus Whiteinella (Whiteinella baltica, Whiteinella cf. baltica, Whiteinella aff. archaeocretacea, Whiteinella? sp.), besides of Muricohedbergella cf. delrioensis, Muricohedbergella sp. Clavihedbergella simplex and Falsotruncana? sp. Based on this planktonic association, as well the presence of Sapucariella multidifferentis, the sample was attributed to Cenomanian-Turonian (94,03), in the Zone W. archaeocretacea. The identified association shows the domain of opportunistic taxa (turrinilids, heterohelicids and hedbergenilids) from mesotrophic to eutrophic environment, supporting oxygen level variations and being important global markers of OEA 2 (Cenomanian-Turonian).
Bookmarks Related papers MentionsView impact
Estudos Geológicos, 2020
The ANP 1040 core analyzed was collected at a depth of 1900 m in the Equatorial Atlantic Ocean, a... more The ANP 1040 core analyzed was collected at a depth of 1900 m in the Equatorial Atlantic Ocean, around 100.8 km from the coastline of the municipality of Itapipoca, Ceará. Particle size analyzes, geochemistry by X-ray fluorescence, calcium carbonate, organic matter and total nitrogen contents were performed. The data show that the ANP 1040 core contains the mud, sandy mud and muddy facies, composed of bioclastic sediments classified as limestone. The decrease of the marine influence on the sedimentation was observed in the intermediate interval of the core because it presented high levels of Ti/Ca and Fe/Ca ratios. In addition, this interval was correlated to high values of mud, organic matter, and low percentage of carbonate content. The high values of these ratios (Ti/Ca and Fe/Ca) are related to an increase of the continental sedimentary contribution, denoting a period of a greater precipitation in the region, indicating a humid tropical climate that increased the flow of the continental drainages and, consequently, the supply of terrestrial sediments to the continental slope. In addition, the high values of the Ti/Al ratio at the base of the core are related to a supply of eolian sediments, while low values of Ti/Al at the top of the core indicated a fluvial source. This work contributes to the knowledge of the Quaternary Geology of the Icaraí sub-basin, Ceará Basin, Brazilian Equatorial Margin.
Bookmarks Related papers MentionsView impact
Revue de micropaléontologie, 2021
Quaternary deep-sea ostracods supply invaluable data for the understanding of both hydrological a... more Quaternary deep-sea ostracods supply invaluable data for the understanding of both hydrological and sedimentary processes in the continental slope. A huge portion of western South Atlantic bathyal regions is still poorly explored with respect to deep-sea ostracod research. This article contributes to the study of the assemblage ostracod of the Upper Pleistocene of five piston cores recovered in the Cone of Rio Grande, Pelotas Basin, Brazil. Taxonomic analysis revealed 21 species belonging to 13 genera:
Bookmarks Related papers MentionsView impact
Uploads
Papers by Robbyson M Melo
to the necessity of increase in the knowledge on microfossils among graduate and undergraduate students, an extension project of microfossils didactic collection was carried out at the Geology
Department of the Universidade Federal de Pernambuco. For each fossil group (i.e. ostracods, foraminifers, calcareous nannofossils, charophytes, radiolarians, diatoms, conodonts, palynomorphs, fish fragments, echinoid spines, sponge spicules and mollusks) micropaleontological slides were assembled. The origin of the material is varied, with specimens from several Brazilian sedimentary basins and even from other countries. The collections consist in numbered and identified slides, besides the material necessary for their manipulation, such as brushes and spare slides. In each fossil group, the specimens are organized according to the morphology, taxonomy and age. Each slide has instructions for classes inserted in a Guidebook of micropaleontology thoroughly illustrated, with general characteristics of each fossil group and the respective methodology for sample preparation. The collection is intended to be used in practical classes, workshops and short-courses, with biological, petrographic and stereoscopic microscopes, for observation of the morphological structures, identification and solution of problems proposed in the guidebook. Besides the improvement in the paleontology teaching, these collections will also contribute to the qualification of the students as
future professionals.
to the necessity of increase in the knowledge on microfossils among graduate and undergraduate students, an extension project of microfossils didactic collection was carried out at the Geology
Department of the Universidade Federal de Pernambuco. For each fossil group (i.e. ostracods, foraminifers, calcareous nannofossils, charophytes, radiolarians, diatoms, conodonts, palynomorphs, fish fragments, echinoid spines, sponge spicules and mollusks) micropaleontological slides were assembled. The origin of the material is varied, with specimens from several Brazilian sedimentary basins and even from other countries. The collections consist in numbered and identified slides, besides the material necessary for their manipulation, such as brushes and spare slides. In each fossil group, the specimens are organized according to the morphology, taxonomy and age. Each slide has instructions for classes inserted in a Guidebook of micropaleontology thoroughly illustrated, with general characteristics of each fossil group and the respective methodology for sample preparation. The collection is intended to be used in practical classes, workshops and short-courses, with biological, petrographic and stereoscopic microscopes, for observation of the morphological structures, identification and solution of problems proposed in the guidebook. Besides the improvement in the paleontology teaching, these collections will also contribute to the qualification of the students as
future professionals.