title: The sea-level highstand correlated to marine isotope stage (MIS) 7 in the coastal plain of the state of Rio Grande do Sul, Brazil.
abstract: 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 Rosselia sp., and molluscan shells. The sedimentary record indicates coastal aggradation followed by sea-level fall and progradation of the coastline. Thermoluminescence (TL) and electron spin resonance (ESR) ages from sediments and fossil shells point to an age of ∼220 ka for the end of this marine transgression, thus correlating it to MIS 7 (substage 7e). Altimetric data point to a maximum amplitude of about 10 meters above present-day mean sea-level, but tectonic processes may be involved. Paleoceanographic conditions at the time of the highstand and correlations with other deposits in the Brazilian coasts are also discussed.
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Renato P
authors.initials: RP
authors.lastname: Lopes
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Sergio R
authors.initials: SR
authors.lastname: Dillenburg
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Cesar L
authors.initials: CL
authors.lastname: Schultz
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Jorge
authors.initials: J
authors.lastname: Ferigolo
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Ribeiro
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Jamil C
authors.initials: JC
authors.lastname: Pereira
authors.affiliation: Departamento de Geologia, Instituto de Geociências, Universidade Federal de Roraima, Boa Vista, RR, Brasil.
authors.forename: Elizete C
authors.initials: EC
authors.lastname: Holanda
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Vanessa G
authors.initials: VG
authors.lastname: Pitana
authors.affiliation: Programa de Pós-Graduação em Geociências, Universidade Federal do Rio Grande do Sul/UFRGS, Porto Alegre, RS, Brasil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Kerber
mesh_terms: D000818:Animals; D059001:Aquatic Organisms; D001938:Brazil; D005580:Fossils; D019015:Geologic Sediments; D010163:Paleontology; D011868:Radioisotopes / Q000032:analysis; D055110:Radiometric Dating; D012623:Seawater
chemical_list: D011868:Radioisotopes