The Pisa coastal plain is a portion of the wider Arno strand plain (NW Tuscany) characterized by outcropping juxtaposed beach ridges originated from the shoreline progradation over the last 3000 yrs (Pranzini, 2001). The plain is crossed by the Arno river, that ows through the city of Pisa, and it is bounded by the Serchio river northward (Fig.1). Its “shallow” subsurface records the late-Quaternary cyclic alternation of continental and nearshore deposits (T-R cycles) related to glacis-eustatic sea-level uctuations (Aguzzi et al., 2007; Amorosi et al., 2009). A good konwledge of the stratigraphic framework together with the existence of an abundant stratigraphic database, make this area suitable for high-resolution stratigraphic subsurface reconstructions. Based on the development and testing of an integrated remote sensing-stratigraphic approach, a cross-disciplinary depositional architecture reconstruction (still in progress) of the last 6000-5000 yrs, with particular emphasis on the palaeo-hydrographic evolution, is presented here with the aim to provide new insight into the mechanism of Mediterranean delta plain development. Several sinuous paleo-traces were identied on aerial and multispectral satellite images (Fig. 2). The paleo-traces are attributable to the two main rivers owing in the plain (Arno and Serchio) and occur at dierent depths along the stratigraphic sections (Fig. 3). The data-crossing allows the “calibration” of some paleo-traces from the city of Pisa westward (Fig.4). During the last 5000 yrs BP the paleo-hydrographic network and its related paleo-environments document a two-fold sedimentary evolution (Sarti et al., 2015). The rst phase, characterized by the development of wide deltaic marshlands crossed by shallow channels and lying the antecedent lagoon, started at the beginning of the Eneolithic age (ca. 5000 cal yr BP) and lasted up to the Bronze age (ca. 3800 yr cal BP). Then, an alluvial plain was established in the Pisa city area, passing seawards to a sandy strand plain. The present delta plain began to develop under the inuence of a uvial network whose branches were mainly oriented E-W (Arno River) and N-S (Serchio River). Specically, two sub-stages can be distinguished: i) a phase of intense fuvial activity with deeply-incised channels and poorly drained oodplain conditions, lasting up to the Etruscan period (2500-2200 cal yr BP), and ii) the onset of awell-drained alluvial plain, at the transition with the Roman age (ca. 2000 yr cal BP) and still in evolution, characterized by more stable and less numerous uvial channels. The use of an integrated remote sensing-stratigraphic approach in this study gives good results and it could be exported in similar context although further analyses are required.
Holocene paleo-hydrographic and landscape evolution of the Pisa coastal plain (Tuscany, Italy) integrating remote sensing and high-resolution stratigraphic data
BINI, MONICA;Ciampalini, A.;PAPPALARDO, MARTA;RIBOLINI, ADRIANO;SARTI, GIOVANNI;
2015-01-01
Abstract
The Pisa coastal plain is a portion of the wider Arno strand plain (NW Tuscany) characterized by outcropping juxtaposed beach ridges originated from the shoreline progradation over the last 3000 yrs (Pranzini, 2001). The plain is crossed by the Arno river, that ows through the city of Pisa, and it is bounded by the Serchio river northward (Fig.1). Its “shallow” subsurface records the late-Quaternary cyclic alternation of continental and nearshore deposits (T-R cycles) related to glacis-eustatic sea-level uctuations (Aguzzi et al., 2007; Amorosi et al., 2009). A good konwledge of the stratigraphic framework together with the existence of an abundant stratigraphic database, make this area suitable for high-resolution stratigraphic subsurface reconstructions. Based on the development and testing of an integrated remote sensing-stratigraphic approach, a cross-disciplinary depositional architecture reconstruction (still in progress) of the last 6000-5000 yrs, with particular emphasis on the palaeo-hydrographic evolution, is presented here with the aim to provide new insight into the mechanism of Mediterranean delta plain development. Several sinuous paleo-traces were identied on aerial and multispectral satellite images (Fig. 2). The paleo-traces are attributable to the two main rivers owing in the plain (Arno and Serchio) and occur at dierent depths along the stratigraphic sections (Fig. 3). The data-crossing allows the “calibration” of some paleo-traces from the city of Pisa westward (Fig.4). During the last 5000 yrs BP the paleo-hydrographic network and its related paleo-environments document a two-fold sedimentary evolution (Sarti et al., 2015). The rst phase, characterized by the development of wide deltaic marshlands crossed by shallow channels and lying the antecedent lagoon, started at the beginning of the Eneolithic age (ca. 5000 cal yr BP) and lasted up to the Bronze age (ca. 3800 yr cal BP). Then, an alluvial plain was established in the Pisa city area, passing seawards to a sandy strand plain. The present delta plain began to develop under the inuence of a uvial network whose branches were mainly oriented E-W (Arno River) and N-S (Serchio River). Specically, two sub-stages can be distinguished: i) a phase of intense fuvial activity with deeply-incised channels and poorly drained oodplain conditions, lasting up to the Etruscan period (2500-2200 cal yr BP), and ii) the onset of awell-drained alluvial plain, at the transition with the Roman age (ca. 2000 yr cal BP) and still in evolution, characterized by more stable and less numerous uvial channels. The use of an integrated remote sensing-stratigraphic approach in this study gives good results and it could be exported in similar context although further analyses are required.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
