Evidence of an Marine Isotope Stage 3 transgression at the Baixada Santista, south-eastern Brazilian coast

Abstract

ABSTRACT:In this paper, we present new evidence regarding a Marine Isotope Stage 3 (MIS3) transgression on the south-eastern Brazilian coast (Baixada Santista coastal plain). Data collected from a Standard Penetration Test (SPT) drilling reveal the occurrence of myxohaline sediments between cal BP 45,000 and 41,000. A deeper sequence, which shows a clear transition from terrestrial to a myxohaline environment, was associated with MIS5e. Organic and inorganic proxies have been used to recognize the variations on the terrestrial/myxohaline/marine deposits, as well as to infer about climate and energy of the depositional environment. Environmental change, which could correspond to a sea-level peak or the occurrence of drier conditions, was recognized between 43,000 and 42,000 cal BP. The results reinforce the need for future works on MIS3 variability on the South American Atlantic coast. KEYWORDS:Marine Isotope Stage 3; Late Pleistocene; sea-level. RESUMO: Neste artigo, apresentamos novas evidências sobre a transgressão ocorrida Estágio Isotópico 3 (MIS3) na costa do sudeste do Brasil (Baixada Santista). Dados coletados por meio de um ensaio de penetração em solo (SPT) revelam a ocorrência de sedimentos mixohalinos entre 45.000 e 41.000 anos a.P. Uma sequência mais profunda, que mostra clara transição de ambiente continental para um mixohalino, foi associada ao Estágio Isotópico 5e (MIS5e). Marcadores orgânicos e inorgânicos foram usados para reconhecer as variações dos ambientes ter

Datação Por Luminescência Opticamente Estimulada (Loe) Nas Cristas De Praia Do Delta Do Rio Paraíba Do Sul (Rj): Considerações Sobre a Evolução Geomorfológica Entre O Pleistoceno Superior E O Holoceno

“…Porém, recentemente, Dillenburg et al (2019) sugerem que os registros sedimentares relativos ao MIS 3 podem estar posicionados entre -5 m e -23 m abaixo do nível médio atual, no caso do litoral sul do Brasil. Salvaterra et al (2017) também identifi caram registros transgressivos do mesmo Estágio Isotópico Marinho entre -7 m e -19 m abaixo do nível médio atual, na Baixada Santista. Já Silva et al (2014) verifi caram na planície costeira de Maricá, no litoral fl uminense, que uma sequencia transgressiva teria começado a se desenvolver por volta de 47.000 anos AP, cujos registros encontram-se a aproximadamente -15 m abaixo do nível médio do mar.…”

Late Pleistocene to Holocene variations in marine productivity and terrestrial material delivery to the western South Atlantic

“…Marine productivity in the region is also influenced by upwelling of SACW, which in turn is affected by sea level changes. A MIS 3 high stand was reported in the southern Brazilian coast (Salvaterra et al, 2017;Dillenburg et al, 2019). This sea level rise would be responsible for the landward displacement of the whole water masses system (Mahiques et al, 2007), including the nutrient-rich SACW, seasonally upwelled into the area leading to enhanced productivity.…”

Response to RC1 detailed

“…However, in this manuscript, the authors also note that there may have been a marine incursion from 55-44 ka, although they later dismiss the likelihood of this possibility. This time period, from 50-40 ka, happens to the be the time period during which sea-level high stands are observed globally during MIS 3 (Cann, 2000, Caybioch & Aycliffe, 2001, Hanebuth et al, 2006, Simms et al, 2009, Pico et al, 2016, DaSilva et al, 2017.…”