Palaeogeographical and palaeoenvironmental reconstruction of the Medjerda delta (Tunisia) during the Holocene
Quaternary Studies Review
The progradation of the Medjerda delta has been the subject of many studies since the 19th c. The scale and the rapidity of this phenomenon have early interested researchers in various fields, such as geomorphology, geology, palaeogeography, history, archaeology, or geoarchaeology. This paper aims to reconstruct the palaeoenvironments and the progradation of the northern compartment of the Medjerda delta since the mid-Holocene, which reached around 10 km in 3 millennia. Based on two coring transects, the chrono-stratigraphical study of 7 cores allows us to identify 8 major phases: (1) from the 6th millennium to around 2600 BC, the sea covered the “northern compartment” of the delta and the “corridor” formed by the Utica and Kalaat El Andalous promontories; (2) between 2600 and the 1st c. AD, the wadi progressively filled the corridor between the two promontories; (3) between the 1st c. AD and the 4th c. AD, the marine bay narrowed gradually and isolated a sea arm on the eastern border of the northern compartment of the Medjerda delta; (4) between the 4th and the 7th c. AD, the sedimentation rates exploded, reflecting increased dynamism of of the wadi, which shifted into the northern compartment resulting in the creation of a lagoon; (5) from the 7th to 10th c. AD, a peat bog developed along the northern façade of the headland, while the coastal lagoon progressively closed to the sea (6th - 8th c. AD); (6) between the 10th and the 15th c., the mouth of the wadi progressed to the east; (7) finally, between the 15th and the 18th centuries, the sediments carried by the Medjerda progressively sealed the bay, leaving the tip of the Utica promontory 10 km inland (18th c. AD to the present) (8).
UTICA RIVERS NORTH AFRICA HOLOCENE DELTA SEDIMENTOLOGY CORING PALAEOENVIRONMENT Holocene Delta progradation Palaeogeography Geoarchaeology Tunisia Western Mediterranean Biological indicators