Interpretation of gamma-ray spectrometric data from central region of Borborema Province, Northeast of Brazil

2007 ◽  
Author(s):  
Adriana Chatack Carmelo ◽  
Roberto A. Vitória de Moraes ◽  
Chris Busnello Fianco ◽  
Gustavo de Assunção Mello ◽  
Loiane Gomes de Moraes ◽  
...  
Keyword(s):  
Central Region ◽  
Gamma Ray ◽  
Spectrometric Data ◽  
Borborema Province

Interpretation of gamma-ray spectrometric data from central region of Borborema Province, Northeast of Brazil

2007 ◽  
Author(s):  
Adriana Chatack Carmelo ◽  
Roberto A. Vitória de Moraes ◽  
Augusto C.B. Pires ◽  
Chris Busnello Fianco ◽  
Loiane Gomes de Moraes ◽  
...  
Keyword(s):  
Central Region ◽  
Gamma Ray ◽  
Spectrometric Data ◽  
Borborema Province

scholarly journals The 3D inversion of airborne gamma-ray spectrometric data

2015 ◽  
Vol 2015 (1) ◽  
pp. 1-4
Author(s):  
Brian Minty ◽  
Ross Brodie
Keyword(s):  
Gamma Ray ◽  
3D Inversion ◽  
Spectrometric Data

The 3D inversion of airborne gamma-ray spectrometric data

2016 ◽  
Vol 47 (2) ◽  
pp. 150-157 ◽  
Author(s):  
Brian Minty ◽  
Ross Brodie
Keyword(s):  
Gamma Ray ◽  
3D Inversion ◽  
Spectrometric Data

Semiautomated geologic mapping using self-organizing maps and airborne geophysics in the Brazilian Amazon

Geophysics ◽  
2012 ◽  
Vol 77 (4) ◽  
pp. K17-K24 ◽  
Author(s):  
Cleyton de Carvalho Carneiro ◽  
Stephen James Fraser ◽  
Alvaro Penteado Crósta ◽  
Adalene Moreira Silva ◽  
Carlos Eduardo de Mesquita Barros
Keyword(s):  
Gamma Ray ◽  
Gold Mineralization ◽  
Brazilian Amazon ◽  
Geophysical Data ◽  
Self Organizing Map ◽  
Self Organizing Maps ◽  
Spectrometric Data ◽  
Rock Types ◽  
Geologic Map ◽  
Self Organizing

A self-organizing map (SOM) approach has been used to provide an integrated spatial analysis and classification of airborne geophysical data collected over the Brazilian Amazon. Magnetic and gamma ray spectrometric data were used to extract geophysical signatures related to the spatial distribution of rock types and to produce a geologic map over the prospective Anapu-Tuerê region. Particular emphasis was given to discriminating and identifying rock types, and the processes related to gold mineralization, which are known to occur in the Anapu-Tuerê region. SOM was able to identify and map distinctive geophysical signatures related to the various geologic units identified on the published geologic map. Furthermore, SOM was able to identify and enhance very subtle signatures derived jointly from the magnetic and gamma ray spectrometric data that could be related to geologic processes present in the area. These results demonstrate the effectiveness of using SOM as a tool for geophysical data analysis and for semiautomated mapping in regions such as the Amazon.

scholarly journals Characterization of Ar-Rassafeh Badyieh area (Area-2), Syria by using the airborne gamma-ray spectrometric and fractal modelling techniques

2019 ◽  
Vol 49 (4) ◽  
pp. 459-478
Author(s):  
Jamal Asfahani
Keyword(s):  
Gamma Ray ◽  
Geological Mapping ◽  
Modelling Technique ◽  
Study Region ◽  
Spectrometric Data ◽  
Modelling Techniques ◽  
Geological Map

Abstract The available aerial gamma-ray spectrometric data of Ar-Rassafeh Badyieh area (Area-2) are used herein for geological interpretations and mapping purposes. Those data are interpreted by the concentration-number (C-N) fractal modelling technique, with the use of log-log graphs. According to C-N model, different radioactive ranges of TC, eU, eTh, and K have been isolated. Those ranges are thereafter used to characterize the lithological outcrops in the study area. The radioactive signatures of all the outcrops in Area-2 have been discussed and documented through establishing the C-N maps of TC, eU, eTh, and K, and benefiting of the available geological map. The C-N fractal modelling technique proves its efficacy, where radioactive and lithological boundaries of outcrops are in concordance. The case study presented in this paper shows the importance and the role of airborne gamma-ray spectrometric and fractal modelling techniques to support the geological mapping and the interpretations in geological context, particularly when the study region is rugged and difficult to be accessed.

scholarly journals IDENTIFICAÇÃO GAMAESPECTROMÉTRICA DE PLACERES RUTILO-MONAZÍTICOS NEOPROTEROZÓICOS NO SUL DA FAIXA SERIDÓ, NORDESTE DO BRASIL

2010 ◽  
Vol 28 (1) ◽  
Author(s):  
Sebastião Milton P. da Silva ◽  
Álvaro P. Crósta ◽  
Francisco J.F. Ferreira ◽  
Hartmut Beurlen ◽  
Adalene M. Silva ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Coarse Grained ◽  
Granitic Rocks ◽  
Gamma Ray Spectrometry ◽  
Geological Data ◽  
Borborema Province ◽  
Two Samples ◽  
Scanning Electron ◽  
The Eu ◽  
Sem Analyses

Dados digitais de um aerolevantamento gamaespectrométrico cobrindo seqüência crustal Neoproterozóica da Faixa Seridó (FSe) foram processados e analisados juntamente com medidas de gamaespectrometria terrestre, fotos aéreas e dados geológicos de campo, objetivando a caracterização e o mapeamento litogeofísico de granitos pegmatíticos e campos de pegmatitos associados, bem como de litologias e unidades litoestratigráficas do Grupo Seridó. A interpretação das imagens individuais e ternária dos canais do urânio (eU), do tório (eTh) e do potássio (K), além das razões eU/eTh e eTh/K, possibilitou a identificação de anomalias de tório associadas a metaconglomerados e metarenitos intercalados nos quartzitos da Formação Equador, constituídos de fragmentos e seixos de quartzo, muscovita e concentrações de minerais pesados, dominantemente hematita, ilmenita, monazita, rutilo, titanita e zircão. A análise semiquantitativa em grãos minerais de duas amostras dessas rochas, por microscopia de varredura eletrônica (MEV-EDS), revelou teores máximos de 79,4% de ThO2 e 87,7% de ETR (Ce, La, Nd) em monazitas; 99,2% de TiO2 em ilmenita e rutilo e 1,81 % de Hf02 em zircão. Também foram identificadas anomalias de tório em sedimentos de idade cenozóica na mesma região.Keywords : gamaespectrometria; sensoriamento remoto; placeres rutilo-monazíticos; Província Borborema; Faixa Seridó.ABSTRACTAerial gamma-ray survey data covering Neoproterozoic supracrustal sequences in the Seridó Belt were processed and analyzed together with ground gamma-ray data, air photos and geological data for lithogeophysical characterization and mapping of granitic rocks, related pegmatites fields and lithological units of Seridó Group. Interpretation was based on individual and ternary images of the three radio-elements and the eU/eTh and eTh/K ratios, and allowed the discovery of thorium anomalies associated with coarse-grained metarenites and metaconglomerates facies intercalated with quartzites of the Equador Formation. High contents of iron oxides, ilmenite, monazite, rutile, titanite and zircon were identified by ore microscopy of polished sections in the metaconglomerate's matrix. Semiquantitative scanning electron microscopy (SEM) analyses in minerals of two samples revealed up to 79.4% of Th02 and 87.7% of REE in monazites; up to 99.2% of Ti02 in ilmenite and rutile and up to 1.81 % of HfO2 in zircon. Gamma-ray anomalies due to thorium were also identified in association with sediments of Cenozoic age in the region.Keywords : gamma-ray spectrometry; remote sensing; rutile-monazite placers; Borborema Province; Seridó Belt.

scholarly journals The Supernova/GRB Connection

2005 ◽  
Vol 192 ◽  
pp. 403-410 ◽  
Author(s):  
P. Höflich ◽  
D. Baade ◽  
A. Khokhlov ◽  
L. Wang ◽  
J.C. Wheeler
Keyword(s):  
Black Hole ◽  
Neutron Star ◽  
Central Region ◽  
Stellar Evolution ◽  
Axial Symmetry ◽  
Energy Deposition ◽  
Gamma Ray ◽  
Massive Stars ◽  
Core Collapse ◽  
Supernova Explosions

SummaryWe discuss the possible connection between supernova explosions (SN) and gamma-ray bursters (GRB) from the perspective of our current understanding of SN physics. Core collapse supernovae (SN) are the final stages of stellar evolution in massive stars during which the central region collapses, forms a neutron star (NS) or black hole, and the outer layers are ejected. Recent explosion scenarios assumed that the ejection is due to energy deposition by neutrinos into the envelope but detailed models do not produce powerful explosions. There is new and mounting evidence for an asphericity and, in particular, for axial symmetry in several supernovae which may be hard to reconcile within the spherical picture. The 3-D signatures are a key to understand core collapse supernovae and the GRB/SN connection. In this paper we study the effects and observational consequences of asymmetric explosions.

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