The role played by human activity in coastline changes indicates a general tendency of retreating coasts, especially deltaic environments, as a result of the recent trend of sea level rise as well as the blockage of the transfer of sediments towards the coast, especially due to the construction of dams. This is particularly important in deltaic environments which have been suffering a dramatic loss of area in the last decades. In contrast, in this paper, we report the origin and evolution of an anthropogenic delta, the Valo Grande delta, on the south-eastern Brazilian coast, whose origin is related to the opening of an artificial channel and the diversion of the main flow of the Ribeira de Iguape River. The methodology included the analysis of coastline changes, bathymetry and coring, which were used to determine the sedimentation rates and grain-size changes over time. The results allowed us to recognize the different facies of the anthropogenic delta and establish its lateral and vertical depositional trends. Despite not being very frequent, anthropogenic deltas represent a favorable environment for the record of natural and anthropogenic changes in historical times and, thus, deserve more attention from researchers of different subjects.

Após a abertura do canal artificial do Valo Grande, na primeira metade do século XIX, a região do Sistema Estuarino-Lagunar de Cananéia-Iguape, denominada Mar Pequeno, vem sendo influenciada por um intenso processo de assoreamento que mudou, numa curta escala de tempo, a morfologia e sedimentação do local, com a consequente formação de um delta intralagunar antropogênico. Essas evidências foram abordadas e analisadas neste trabalho por meio da elaboração de modelos digitais de terreno, realizados a partir de dados batimétricos obtidos em campo. Além disso, com a elaboração de mapas vetoriais realizados a partir da digitalização da linha de costa de imagens de satélite e mapas topográficos, foi possível fazer um estudo da mudança geomorfológica da linha de costa. O processo de erosão do Valo Grande foi demonstrado através de comparações das seções de perfis batimétricos efetivadas nos anos de 1891 e 1907 pela Comissão Geográfica e Geológica do Estado de São Paulo e dos perfis adquiridos em campo no ano de 2008, com a finalidade de obter a variação da largura e da profundidade do canal ao longo desses anos.

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In this work, we present a brief revision of the geological evidence of human activities in the coast of São Paulo (Southeast Brazil), from pre-historical times to the present. We analyze case studies in different sectors of the coast, identifying the main historical causes that resulted in environmental changes with their consequent imprint in the sedimentary column. There was a south-to-north trend in the occupation at the colonization period (1500 onwards), essentially determined by differences in the geomorphology of the area. Finally, the accumulation of artificial radionuclides and plastic debris in the sediments is discussed. Keywords: Human occupation; coastline; SE Brazil ResumoNeste trabalho, apresentamos uma breve revisão das evidências geológicas das atividades humanas no litoral de São Paulo (Sudeste do Brasil), desde os tempos pré-históricos até o presente. Analisamos estudos de caso em diferentes setores da costa, identificando as principais causas históricas que resultaram em mudanças ambientais com sua consequente impressão na coluna sedimentar. Havia uma tendência sul-norte na ocupação no período de colonização (1500 em diante), essencialmente determinada por diferenças na geomorfologia da área. Finalmente, o acúmulo de radionuclídeos artificiais e detritos plásticos nos sedimentos é discutido. Palavras-chave: Ocupação humana; litoral; SE do Brasil IntroductionThe definition of the beginning of the Anthropocene in coastal areas is undoubtedly chronologically much younger than the human occupation of the coasts itself (Menzel, 1959;Kaplan, 1980;Stringer, 2000). Actually, the definition of the base of this new epoch is, somehow, still a matter of debate, since the geological/ geochemical evidence of the end of the Holocene can be interpreted in different ways (Steffen et al., 2007;Leorri et al., 2014;Irabien et al., 2015;Zalasiewicz et al., 2015;Waters et al., 2016). It is worth observing that in different coastal and marine areas the evidence goes back to pre-Industrial ages (Crutzen and Steffen, 2003;Martins et al., 2013;Leorri et al., 2014;Irabien et al., 2015).In this paper, we present a brief review of the geological imprint of the human occupation of the coast of São Paulo (Southeast Brazil), an area of a relatively recent historical occupation, caused by different economic activities, but with geological evidence of pre-Columbian settlings. The main aim of this work is to recognize when, why and how the geological records show evidence of the beginning of the Anthropocene in this coastal area. Area of StudyThe area of study corresponds to the coast of São Paulo, a part of the arc-shaped section of the Brazilian margin known as São Paulo Bight (Zembruscki, 1979) (figure 1). This coastal sector has been divided into different forms. According to Muehe (1998), it is divided into two different compartments, the Northern Crystalline Scarps Littoral and the Coastal Plains and Estuaries Littoral, the difference between them being essentially related to the position of the Serra do Mar mou...