Indicators of Holocene sea level changes along the coast of the states of Pernambuco and Paraíba, Brazil

Abstract

This study deals with the Holocene relative sea level (RSL) changes along the Brazilian northeastern coast, in particular along the states of Pernambuco and Paraíba. It presents 25 sea level superficial indicators, dominantly of a biological nature (i.e., vermetid gastropod tubes encrusted on rocky surfaces, as well as mollusk shells in live positions contained within beachrocks and paleomangrove deposits). Moreover, diatomological and palynological analyses have been carried out on a drilling core obtained from the Olhos d'Água lagoon (Southeastern Recife, Pernambuco state) with a length of about 2.7 m and age of about 8,300 cal yr BP at the base. The envelope RSL change curve obtained through the interpretation of the data indicates that, after reaching the current level ~ 7,400 cal yr BP, a sea level culmination of ~ 3 m above sea level was attained between 4,000 -5,000 cal yr BP, and a general trend of sea level drop occurred until the present, with possible phases of slight oscillations. This is consistent with the oscillation frequency of microscopic marine and freshwater organisms in the sediment core.

Petrography, Stable Isotops and Geochronology of Beachrocks from the Coastline of Rio de Janeiro State, SE Brazil

“…Resultados obtidos para as categorias (b) e (c) sugerem que os beachrocks são indicadores precisos de variações do nível relativo do mar principalmente em ambiente de micromaré como é o caso da costa do Sudeste brasileiro. Essa informação corrobora trabalhos realizados por Hopley (1986), Ramsay (1995), Suguio et al (2013), Castro et al (2014) e Malta et al (2017).…”

Impacts of Holocene and modern sea‐level changes on estuarine mangroves from northeastern Brazil

“…Studies based mainly on dating mollusk shells and vermetids indicate a middle Holocene highstand between 1 and 5 m above mean sea-level at about 5500 cal yrs BP in southeastern and northeastern Brazil (Angulo et al, 2006;Angulo et al, 2016;Caldas et al, 2006;Castro et al, 2014;Martin, 2003;Martin et al, 2003;Suguio et al, 2013). The variation, trends and amplitudes of Brazilian Holocene RSL is a topic still open to discussion.…”

“…Studies based mainly on dating mollusk shells and vermetids indicate a middle Holocene highstand between 1 and 5 m above mean sea-level at about 5500 cal yrs BP in southeastern and northeastern Brazil (Angulo et al, 2006;Angulo et al, 2016;Caldas et al, 2006;Castro et al, 2014;Martin, 2003;Martin et al, 2003;Suguio et al, 2013). RSL fall since then may have been gradual (Angulo et al, 2006) or may have seen oscillations (Martin, 2003;Suguio et al, 2013). In contrast, along the Venezuelan, Suriname and northern Brazilian coasts, RSL appears to have reached the modern level in the mid-Holocene, and has remained stable since then Rull et al, 1999).…”

Holocene Paleo-Sea Level in Southeastern Brazil: An Approach Based on Vermetids Shells

“…In Brazil, these studies have mainly been conducted since the 1970's and the vertical amplitudes ranged from 2 to 5.3 m (e.g. Martin and Suguio, 1975;Suguio et al, 1985Suguio et al, , 2013Dominguez et al, 1990;Martin and Suguio, 1992;Angulo and Lessa, 1997;Angulo et al, 2002Angulo et al, , 2006Dias, 2009;Castro et al, 2014).…”

“…Biological indicators, particularly sessile organisms as worm snails Vermetidae (Mollusca: Gastropoda), have been largely used in many studies about relative sea level change (Van Andel and Laborel,1964;Suguio et al, 1985Suguio et al, , 2013Laborel, 1986;Pirazzoli, 1991;Laborel-Deguen, 1994, 1996;Pirazzoli et al, 1996;Angulo and Lessa, 1997;Angulo et al, 1999Angulo et al, , 2006Antonioli et al, 1999;Baker and Haworth, 2000;Lambeck et al, 2004;Vescogni et al, 2008;Dias, 2009), because they are excellent proxies of former sea levels. They are able to provide reliable information about mean sea level position in the past due to their short lifetimes (Laborel, 1986;Laborel-Deguen, 1994, 1996;Pirazzoli et al, 1996;Angulo et al, 2006).…”