Inter-scientific Dialogue – Multidisciplinary analysis of the navigability and anchorage conditions during the Roman period (Esposende)
PROJECT REFERENCE: PTDC/EPH-ARQ/5204/2012
The primary goal of this project is to investigate the navigability and anchorage conditions during the Roman period between the rivers Ave and Neiva (including the Cávado), with the aim of understanding the supply routes for the coastal areas within the vast region of the conventus bracaraugustanus and its provincial capital, Bracara Augusta. Given the complexity of this topic, a multidisciplinary approach is necessary, involving the integration of data from geosciences (such as geomorphology, sedimentology, stratigraphy, and chemistry) and natural sciences (such as paleoecology), along with testimonies from social sciences (including archaeology, historical cartography, and literary and epigraphic sources).
Regarding geomorphological, stratigraphic, and sedimentological indicators, our objective is to analyse the paleoenvironmental conditions of the coastal zone between those estuaries during the Roman period. Previous studies suggest that during this time, the estuaries of the Cávado and Ave rivers were wider and more concaved compared to their current state (Granja e Morais, 2010). Additionally, it has been suggested that wetlands occupied depressed areas along the coast (Granja 1990, 1997, 2002).
These landscape changes coincide with significant climate fluctuations, which impacted the relative sea level position. This is evident in certain lagoon deposits documented in the coastal zone north of the Cávado estuary, where Roman-era artefacts have been found. A concentration of these remains was discovered on a beach north of Esposende, suggesting the presence of a probable Roman port. Numerous amphorae fragments, particularly Haltern 70, as well as cetias, were unearthed, indicating the potential existence of a Roman villa in the vicinity. The significance of these archaeological findings is further supported by the literary and epigraphic sources alluding to the Roman city of Bracara Augusta, which describe the existence of a sea gulf and underscore the city’s commercial importance.
The mouth of the Cávado would have been situated to the south of its current location, in Fão, where geomorphological and sedimentological evidence suggest the presence of a canal. Modern-era cartography data, particularly the letter of João Teixeira I of 1648, depicts the mouth of the Cávado river in Fão and portrays the Ave river’s mouth as wider and gulf-shaped, a stark contrast to its current configuration.
The questions raised in the previous points corroborate the data related to weather and oceanographic conditions, indicating potentially different navigability conditions during the Roman period that may have been more favourable than those existing today.
This project aims to address those questions through an integrated and comprehensive paleo-environmental reconstruction. This reconstruction will rely on geomorphological, sedimentological-stratigraphic, paleo-ecological and radio-chronological analyses. In turn, these analyses will provide valuable insights on the climate, sea levels, hydrodynamics, and sedimentary supply during the Roman period.