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| LOPES,RENATO P.; DILLENBURG,SERGIO R.; SCHULTZ,CESAR L.. |
| ABSTRACT Loess consists of silt-dominated sediments that cover ~10% of the Earth's surface. In southern South America it occurs in Argentina, Bolivia, Paraguay and Uruguay, and its presence in southern Brazil was never studied in detail. Here is proposed a new lithostratigraphic unit, Cordão Formation, consisting of loess deposits in the southern Brazilian coastal plain. It consists of fine-very fine silt with subordinate sand and clay, found mostly in lowland areas between Pleistocene coastal barriers. These sediments are pale-colored (10YR hue) and forms ~1,5-2,0 meter-thick stable vertical walls. The clay minerals include illite, smectite, interstratified illite/smectite and kaolinite, the coarser fraction is mostly quartz and plagioclase. Caliche and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chuy Creek; Coastal plain; Last glacial stage; Loess; Pleistocene. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000602143 |
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| LOPES,RENATO P.; DILLENBURG,SERGIO R.; SCHULTZ,CESAR L.; FERIGOLO,JORGE; RIBEIRO,ANA MARIA; PEREIRA,JAMIL C.; HOLANDA,ELIZETE C.; PITANA,VANESSA G.; KERBER,LEONARDO. |
| The coastal plain of the state of Rio Grande do Sul, in southern Brazil, includes four barrier-lagoon depositional systems formed by successive Quaternary sea-level highstands that were correlated to marine isotope stages (MIS) 11, 9, 5 and 1, despite the scarcity of absolute ages. This study describes a sea-level highstand older than MIS 5, based on the stratigraphy, ages and fossils of the shallow marine facies found in coastal barrier (Barrier II). This facies outcrops along the banks of Chuí Creek, it is composed of fine, well-sorted quartz sand and contains ichnofossils Ophiomorpha nodosa and Rosseliasp., and molluscan shells. The sedimentary record indicates coastal aggradation followed by sea-level fall and progradation of the coastline.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Barrier II; Chuí Creek; MIS 7; Pleistocene; Paleoceanography. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000401573 |
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