scholarly journals The Holocene coastal deposits of Sussex: a re-evaluation

2013 ◽  
pp. 31-59
Author(s):  
Martyn Waller ◽  
Antony Long
Keyword(s):  
The Holocene ◽  
Coastal Deposits

scholarly journals MAPA GEOLÓGICO DA PLANÍCIE COSTEIRA ENTRE O RIO SAÍ-GUAÇU E A BAÍA DE SÃO FRANCISCO, LITORAL NORTE DO ESTADO DE SANTA CATARINA

2004 ◽  
Vol 55 ◽  
Author(s):  
Rodolfo José ANGULO ◽  
Maria Cristina De SOUZA
Keyword(s):  
Coastal Plain ◽  
Sedimentary Cover ◽  
The State ◽  
Northern Coast ◽  
Littoral Drift ◽  
Santa Catarina ◽  
Upper Pleistocene ◽  
The Holocene ◽  
Geological Map ◽  
Coastal Deposits

A geologia de superfície da região costeira, entre o Rio Saí-Guaçu e a Baía de São Francisco, litoral norte de Santa Catarina, é constituída por rochas do embasamento cristalino Pré-Cambriano e pela cobertura sedimentar do Cenozóico. O objetivo deste trabalho é apresentar um novo mapa geológico dessa cobertura, na escala 1:50.000, com ênfase na planície costeira. Na área, foram identificadas as seguintes unidades: Fm. Mina Velha do Mioceno Inferior; colúvios, leques aluviais e depósitos fluviais, do Quaternário indiferenciado; terraços costeiros do Pleistoceno Superior (120.000 anos A.P.) e do Holoceno (< 7.000 anos A.P.); planícies paleoestuarinas do Holoceno; dunas, praias e mangues atuais. A distribuição em superfície e subsuperfície e o empilhamento das fácies dos depósitos costeiros permitem compreender alguns aspectos da evolução geológica e paleogeográfica da área durante o Quaternário. A ocorrência de extensos terraços do Pleistoceno e Holoceno, a presença de paleolagunas na retaguarda dos terraços e a ocorrência de sedimentos argilosos lagunares sob os terraços permitem inferir que, durante os ciclos transgressivos regressivos do Pleistoceno superior e Holoceno, existiram na região barreiras transgressivas e regressivas. A extensão das planícies paleoestuarinas indica que durante o máximo transgressivo do Holoceno existiam grandes estuários e lagunas. A morfologia dos cordões litorâneos evidencia que no Holoceno houve a formação de esporões paralelos à costa, que teriam crescido para o norte sob o efeito da deriva litorânea predominante. O crescimento desses esporões teria desviado a desembocadura do Rio Saí-Mirim para o norte. Durante essa migração, o rio erodiu a parte interna desses esporões e, provavelmente, as barreiras transgressivas do Holoceno. GEOLOGICAL MAP OF THE COASTAL PLAIN BETWEEN THE SAÍ-GUAÇU RIVER AND SÃO FRANCISCO BAY, NORTHERN COAST OF THE STATE OF SANTA CATARINA Abstract The studied area is located in the northeastern area of the State of Santa Catarina between 25o57' S and 26o14' S. The surface geology of the area is composed by rocks from the Precambrian basement and from the Cenozoic sedimentary cover. In conventional geological maps, the Cenozoic sedimentary package appears as an undifferentiated unit (e.g. Siga Jr. et al. 1993). Martin et al. (1988) presented the first map of the coastal Quaternary of the State of Santa Catarina, in 1:200,000 scale. Later, Horn Filho (1997) presented a map, in the scale 1:50,000, of the São Francisco do Sul region. The objective of this study is to present a new geological map, in the scale 1:50,000, of the coastal plain between the Saí-Guaçu River and the São Francisco Bay. In the studied area the following Cenozoic age units were identified: Mina Velha Formation, probably of Lower Miocene; colluvium and alluvial fans of undifferentiated Quaternary; fluvial deposits of undifferentiated Quaternary; Upper Pleistocene coastal terraces (120,000 years B.P.); Holocene coastal terraces (< 7,000 years B.P.); Holocene paleoestuarine plains; dunes; beaches and mangroves. The distribution on the surface and subsurface and the layers of facies of the coastal deposits allow an understanding of some aspects of the geological and paleogeographical evolution of the area during the Quaternary. There are extensive Pleistocene and Holocene terraces, the presence of paleolagoons on the terrace backs and also fine lagoon sediments below the terraces makes one infer that during the Upper Pleistocene and Holocene there were transgressive barrier and regressive beach/foredune ridges in the region, similar to those described by Lessa et al. (2000) in the State of Paraná. The extension of the paleoestuarine plains indicates that during the Holocene transgressive maximum there were large estuaries and lagoons. The morphology of the beach/foredune ridges provides evidence that in the Holocene spits parallel to the coast foreland that would have grown northward due to the effect of the dominant littoral drift. The growth of these spits caused the migration of the inlet of Saí-Mirim River more than 6 km northward throughout the last 5,000 years. During this migration the river eroded the internal part of these spits and the Holocene transgressive barriers.

Sequential growth of early diagenetic freshwater siderites in the Holocene coastal deposits, Korea

2004 ◽  
Vol 169 (1-2) ◽  
pp. 107-120 ◽  
Author(s):  
D.I Lim ◽  
H.S Jung ◽  
S.Y Yang ◽  
H.S Yoo
Keyword(s):  
The Holocene ◽  
Coastal Deposits

scholarly journals The Holocene depositional history of the IJzer palaeovalley (Western Belgian coastal plain) with reference to the factors controlling the formation of intercalated peat beds

2000 ◽  
Vol 2 (1-2) ◽  
pp. 39-72 ◽  
Author(s):  
Cecile BAETEMAN
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Sediment Supply ◽  
Sedimentary Sequence ◽  
Channel Network ◽  
Depositional History ◽  
The Holocene ◽  
Sea Level Fluctuations ◽  
Coastal Deposits ◽  
The Many

Detailed stratigraphic and sedimentological work, together with radiocarbon datings of the Holocene coastal deposits in the IJzer palaeovalley was performed in order to document the formation of the sedimentary sequence in relation to the controlling factors, to reveal the stratigraphical significance of intercalated peat beds, and to reconstruct the depositional history. Because of the many controversies relating to these topics, the Belgian literature has been reviewed. An initial rapid sea-level rise prior to ca. 7800 cal BP resulted in a rapid shift of the facies belts across the palaeovalley and was associated with rapid filling with no formation of intercalated peat beds. A deceleration in the rate of the sea-level rise with sufficient sediment supply produced rapid facies changes registered as frequent alternations of mud, peat and gyttja in the sedimentary sequence deposited between ca. 7800 and 6000 cal BP. The facies changes are determined by a sedimentological control related to the tidal channel and creek network, and not by sea-level fluctuations. Periods of peat growth lasted longer and the lateral extension became more widespread as deceleration of the sea-level rise and filling of the plain continued. This was associated with progradation of the shoreface from ca. 6000 cal BP onwards. Tidal conditions returned to the area from ca. 4000 cal BP onwards. This return was accompanied by erosion and landward migration of the shoreface and channel network. This study demonstrates that the tripartite stratigraphy using Dunkerque and Calais as units should be abandoned in favour of lithological and sedimentological descriptions and age determinations together with environmental interpretation.

Signature of Transpressional Tectonics in the Holocene Stratigraphy of Lake Azuei, Haiti: Preliminary Results From a High-Resolution Subbottom Profiling Survey

2018 ◽  
Author(s):  
Marie-Helene Cormier ◽  
Heather Sloan ◽  
Dominique Boisson ◽  
Britta Brown ◽  
Kelly Guerrier ◽  
...  
Keyword(s):  
High Resolution ◽  
The Holocene ◽  
Preliminary Results ◽  
Holocene Stratigraphy ◽  
Subbottom Profiling
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