Correlação entre a morfologia e a geometria interna de dunas eólicas parabólicas, com auxílio de GPR
Parabolic dunes generally occur in coastal environments in tropical zones, and are deposits influenced by several factors besides the wind regime, such as precipitation, vegetation cover and water table. In view of their particularities, a model of the geophysical signatures of sedimentary struct...
Na minha lista:
| Autor principal: | |
|---|---|
| Outros Autores: | |
| Formato: | Dissertação |
| Idioma: | pt_BR |
| Publicado em: |
Brasil
|
| Assuntos: | |
| Endereço do item: | https://repositorio.ufrn.br/jspui/handle/123456789/28715 |
| Tags: |
Adicionar Tag
Sem tags, seja o primeiro a adicionar uma tag!
|
| Resumo: | Parabolic dunes generally occur in coastal environments in tropical zones, and are
deposits influenced by several factors besides the wind regime, such as precipitation,
vegetation cover and water table. In view of their particularities, a model of the
geophysical signatures of sedimentary structures of open and closed parabolic coastal
dunes is presented here. Geophysical acquisition with GPR and topographic survey with
UAV and geodetic GPS were carried out on dunes in Rio do Fogo and São Bento do
Norte / RN, Brazil, and allowed to describe the internal structures of the following
morphological features: depositional lobe, trailing arms, back ridges, dune track ridges
and deflation basin. The depositional lobe has progressive foresets, as well as trailing
arms. The deflation basin, in turn, has concordant and thin layers as a result of the
accumulation of thicker grains and preservation of the blades. The dune track ridges and
back ridges occur both in the deflation basin as arched sandy ridges, with a lack of
definition in the literature when differentiating these features, especially with regard to
their origins. The internal structures identified for the dune track ridges point to two
signatures in this feature: at its base there is the preservation of progradant layers
reliquary to the migration of the open parabolic dune, separated by a superposition
surface above which trapping layers occur. The back ridge is related to the erosive event
of the closed parabolic dune, which results from a wind reactivation or precedes a
blowout. |
|---|