Geoarchaeology as a tool to understand ancient navigation in the northern Persian Gulf and the harbour history of Siraf

A shift in maritime trade from the western to eastern Persian Gulf during the Abbasid dynasty, previously attributed to an earthquake around 977 CE, was instead driven by changing sea levels and wind patterns. Geoarchaeological data from Siraf reveal two occupation phases (2 BC–317 CE and under Shapur II), with a fall in relative sea level and stronger summer Shamal winds after 550 CE likely reducing the navigability of western ports, making Siraf the preferred alternative. Optimal sailing windows were August for arrivals and October for departures, but rising sea levels and coastal erosion between 850–1000 CE degraded harbour conditions, contributing to economic decline.

Pourkerman, M., Marriner, N., Morhange, C., Djamali, M., Spada, G., Amjadi, S., Vacchi, M., Lahijani, H., Esmaeili Jelodar, M., Tofighian, H., & Naderi Beni, A. (2020). Geoarchaeology as a tool to understand ancient navigation in the northern Persian Gulf and the harbour history of Siraf. Journal of Archaeological Science: Reports, 33, 102539. https://doi.org/10.1016/j.jasrep.2020.102539