MODELO DE OCORRÊNCIA E GÊNESE DA ARGILA BENTONÍTICA DE BOA VISTA, CAMPINA GRANDE, PARAÍBA
MODELO DE OCORRÊNCIA E GÊNESE DA ARGILA BENTONÍTICA DE BOA VISTA, CAMPINA GRANDE, PARAÍBA
| dc.contributor | en-US | |
| dc.contributor | pt-BR | |
| dc.creator | GOPINATH, TUMKUR RAJARAO | |
| dc.creator | SCHUSTER, HANS-DIETER | |
| dc.creator | SCHUCKMANN, WALTER KLAUS | |
| dc.date | 2018-08-02 | |
| dc.date.accessioned | 2023-06-19T16:39:38Z | |
| dc.date.available | 2023-06-19T16:39:38Z | |
| dc.identifier | https://ppegeo.igc.usp.br/index.php/rbg/article/view/12287 | |
| dc.identifier.uri | https://repositorioslatinoamericanos.uchile.cl/handle/2250/6693906 | |
| dc.description | Bentonitic clay deposits of Boa Vista region, Paraíba, occur in small basins distributed over a distance of 10 km, and are surrounded by Tertiary basalts and Precambrian granites and gneisses. These argilaceous sediments are caracterized by horizontal laminations, intercalations of sand and silt, and rhythmic interlaminations of clay and silica toward top of the sequence. There is a close genetic relationship between the bentonitic clay and the basaltic flows. Clay sequences in the eastern part of the region are not only underlain by altered, green, vesicular and scoriaceous flows, but also enclosed by similar but unaltered flows. Lapilli tuff pyroclastics occur sporadically over the flows surrounding the clay basin. The basaltic flows and lapillis are rich in volcanic glass and vitric basalt fragments. These basaltic flows contain columnar joints, flow structures and vitrified zones. Volcanic glass in the flows below the clay sequence is devitrified to clay particles and quartz with "ghost" structure, whereas the plagioclase lathsare partially replaced bycalcedony. In the western part of the region, the bentonitic clay overly gneissic rocks and the basaltic flows in and around these clay deposits are lacking. It is concluded that the bentonitic clays of Boa Vista are the product of devitrification and alteration of glassy pyroclastics that were deposited in the existing basins. These pyroclastics were originated as a result of explosive volcanic activity locally confined to the eastern part of the region. | en-US |
| dc.description | Bentonitic clay deposits of Boa Vista region, Paraíba, occur in small basins distributed over a distance of 10 km, and are surrounded by Tertiary basalts and Precambrian granites and gneisses. These argilaceous sediments are caracterized by horizontal laminations, intercalations of sand and silt, and rhythmic interlaminations of clay and silica toward top of the sequence. There is a close genetic relationship between the bentonitic clay and the basaltic flows. Clay sequences in the eastern part of the region are not only underlain by altered, green, vesicular and scoriaceous flows, but also enclosed by similar but unaltered flows. Lapilli tuff pyroclastics occur sporadically over the flows surrounding the clay basin. The basaltic flows and lapillis are rich in volcanic glass and vitric basalt fragments. These basaltic flows contain columnar joints, flow structures and vitrified zones. Volcanic glass in the flows below the clay sequence is devitrified to clay particles and quartz with "ghost" structure, whereas the plagioclase lathsare partially replaced bycalcedony. In the western part of the region, the bentonitic clay overly gneissic rocks and the basaltic flows in and around these clay deposits are lacking. It is concluded that the bentonitic clays of Boa Vista are the product of devitrification and alteration of glassy pyroclastics that were deposited in the existing basins. These pyroclastics were originated as a result of explosive volcanic activity locally confined to the eastern part of the region. | pt-BR |
| dc.format | application/pdf | |
| dc.language | por | |
| dc.publisher | Sociedade Brasileira de Geologia | pt-BR |
| dc.relation | https://ppegeo.igc.usp.br/index.php/rbg/article/view/12287/11845 | |
| dc.rights | Direitos autorais 2018 Revista Brasileira de Geociências | pt-BR |
| dc.source | Revista Brasileira de Geociências; v. 11, n. 3 (1981); 185-192 | en-US |
| dc.source | Revista Brasileira de Geociências; v. 11, n. 3 (1981); 185-192 | es-ES |
| dc.source | Revista Brasileira de Geociências; v. 11, n. 3 (1981); 185-192 | pt-BR |
| dc.source | 0375-7536 | |
| dc.subject | en-US | |
| dc.subject | pt-BR | |
| dc.title | MODELO DE OCORRÊNCIA E GÊNESE DA ARGILA BENTONÍTICA DE BOA VISTA, CAMPINA GRANDE, PARAÍBA | en-US |
| dc.title | MODELO DE OCORRÊNCIA E GÊNESE DA ARGILA BENTONÍTICA DE BOA VISTA, CAMPINA GRANDE, PARAÍBA | pt-BR |
| dc.type | info:eu-repo/semantics/article | |
| dc.type | info:eu-repo/semantics/publishedVersion | |
| dc.type | pt-BR |