This paper investigates whether the wetlands of the Estero de la Nao, a tidal channel and small tributary within the lower Guadiana estuary (Gulf of Cádiz, SW Iberia), were able to serve as a potential natural harbor location and port of trade for the seafaring Phoenician population. The focus of this study is set on a systematic analysis of sedimentological data.
The lithostratigraphy of three sediment cores shows that at least 8000 years ago open water conditions existed within a marine embayment characterized by sedimentation under estuarine conditions. This situation prevailed for several millennia. From the Early Bronze Age, silting-up processes of the former navigable areas occurred. Additionally, a distinct stratigraphic gap within the sedimentary sequence of one particular sediment core provides strong evidence of ancient dredging activities that attempted to cope with the local siltation processes. In the most recent strata, badly sorted sediments intercalated with brick- and shell fragments provide evidence of a high energy event probably triggered by the great Lisbon earthquake in 1755.