1. |
- Giongo, Adriana, et al.
(författare)
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Distinct deep subsurface microbial communities in two sandstone units separated by a mudstone layer
- 2020
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Ingår i: Geosciences Journal. - : Springer. - 1226-4806 .- 1598-7477. ; 24, s. 267-274
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Tidskriftsartikel (refereegranskat)abstract
- Deep subsurface microbial communities are more abundant in coarse-grained sedimentary rocks such as sandstones than in fine-grained mudstones. The low porosity and low permeability of mudstones are believed to restrict microbial life. Then, it is expected that distinct, isolated microbial communities may form in sandstones separated by mudstones. In this context, the connectivity between microbial communities in different sandstone units can be investigated to infer evolutionary patterns of diversification in space-time, which may potentially contribute with relevant data for analyses of hydraulic connectivity and stratigraphic correlation. In this work, we used high throughput DNA sequencing of a ribosomal 16S gene fragment to characterize the prokaryotic communities found in Permian sandstone samples of the same core that are separated by one mudstone interval, in the Charqueadas coal field, Parana Basin (Southern Brazil). Our samples were collected at âŒ300 m deep, in porous sandstones separated by a thick mudstone package. Differences in the bacterial community structure between samples were observed for the classified OTUs, from phylum to genus. Molecular biology might be further applied as a possible tool to help to understand the spatial and temporal distribution of depositional facies, and the efficiency of low permeability rocks to compartmentalize reservoirs. Ongoing studies aim to extend the present investigation into further analyses regarding lateral changes in microbial communities present in the same sandstone units.
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2. |
- Miller, Dennis J., et al.
(författare)
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Natural gas hydrates in the Rio Grande Cone (Brazil) : A new province in the western South Atlantic
- 2015
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Ingår i: Marine and Petroleum Geology. - : Elsevier. - 0264-8172 .- 1873-4073. ; 67, s. 187-196
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Tidskriftsartikel (refereegranskat)abstract
- The Rio Grande Cone is a large-scale fanlike feature in the continental slope of the Pelotas Basin, Southern Brazil, where ubiquitous world-class bottom simulating reflectors (BSRs) are readily observed in seismic records. With the purpose of searching for natural gas hydrate deposits in the Cone area, four oceanographic cruises were carried out between May 2011 and July 2013, leading to the discovery of two pockmark fields, active faults and gas hydrates in shallow sediments. Multichannel seismic, multibeam echo sounder, side scan sonar and sub-bottom profiler records were used to map the shallow section and select sites for piston core sampling. Gas hydrates were recovered in several piston cores within muddy sediments collected inside pockmarks displaying high backscatter in the multibeam and side scan sonar data. We present two representative piston cores where numerous levels of gas hydrates occur, along with degassing features, authigenic carbonate and soupy sediments. Gas dissociated from gas hydrate samples is dominantly methane (>99.78%) with minor quantities of ethane. The chemical and isotopic compositions of the gas strongly suggest a biogenic origin for the analyzed samples. These new findings are regarded as strong enough evidence to consider the Rio Grande Cone as a new gas hydrate province. (C) 2015 Elsevier Ltd. All rights reserved.
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3. |
- Rodrigues, Luiz Frederico, et al.
(författare)
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The influence of methane fluxes on the sulfate/methane interface in sediments from the Rio Grande Cone Gas Hydrate Province, southern Brazil : A influência dos fluxos de metano na interface sulfato/metano em sedimentos de hidrato de gás do Cone do Rio Grande, Sul do Brasil
- 2017
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Ingår i: Brazilian Journal of Geology. - : FapUNIFESP (SciELO). - 2317-4692 .- 2317-4889. ; 47:3, s. 369-381
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Tidskriftsartikel (refereegranskat)abstract
- Much research has been published regarding the relation between major gas hydrate accumulations and the global carbon cycle. In this context, the determination of the sulfate/methane interface (SMI) depth is of primary importance in order to understand the dynamics of methane flux in the shallow section. This paper identifies the depth of the SMI in sediments based on sulfate and methane concentration profiles in cores recovered in the Rio Grande Cone Gas Hydrate Province, Pelotas Basin, southern Brazil. The shape of methane and sulfate concentration profiles in the sediments can be linked to the local methane flux rate as follows: (i) near linear, high upward-diffusing methane flux coupled with high sulfate diffusion from seawater; (ii) irregular, variable methane flux rates; and (iii) kink-type profile, which is indicative of variable rather than strictly high upward methane flux. The areas in which a high methane flux was identified are spatially associated with gas chimneys in sediments within pockmarks, whereas profiles with low methane flux are present in adjacent areas. These chimneys appear as acoustic blankings in seismic records and can therefore be mapped in subsurface. The wavy-like seismic reflection following the SMI coincides with the occurrence of authigenic carbonate nodules and concretions. In addition, high methane fluxes and the occurrence of concretions and nodules carbonates were correlated by stratigraphic position of the concretions bearing intervals and sulfate profiles
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4. |
- ZACAR, Cláudia Regina Hasegawa, et al.
(författare)
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Atividade de Aprendizado Integradora do curso de Design de Produto da UFPR: proposta de ensino-pesquisa-extensão em resposta à pandemia de COVID-19 (Integrative Learning Activity of the Product Design undergraduate course at UFPR: a teaching-research-extension proposal in response to the COVID-19 pandemic).
- 2021
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Ingår i: Extensão em Foco. - : Universidade Federal do Parana. - 2358-7180 .- 1982-4432. ; 23:Especial, s. 86-107
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Tidskriftsartikel (refereegranskat)abstract
- This paper aims to report an integrative learning activity developed in the Product Design undergraduate course at the Federal University of Paraná (UFPR), in the context of the COVID-19 pandemic. The project theme was the development of personal protective equipment for children, and the activity was planned to integrate teaching (undergraduate students), research (master and PhD students) and extension (external community). Its development adopted a four - stage design method (informational, conceptual, detailing and communication), and was characterized as emergency remote teaching experience, thru the use of technologies such as videoconferences and planning and collaboration tools for remote teamwork. In addition to members of the UFPR internal community, professors and students from the Federal University of Ceará and members of a partner company, ÖUS, also participated in the activity. The activity resulted in four design solutions with potential for implementation, one of which is already in production. In addition, it had a very positive impact on the integration between professors and students, and between the involved institutions. Based on the evaluation of this experience, we believe that this format has the potential to enable the implementation of extension activities in the course curriculum.
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