The aqueduct of Gerasa – Intra-annual palaeoenvironmental data from Roman Jordan using carbonate deposits

Abstract Calcium carbonate (CaCO3) deposits from Roman aqueducts are an innovative archive to obtain local high-resolution palaeoenvironmental and archaeological data in interdisciplinary studies. Deposits from one of the aqueducts of the Roman city of Gerasa provide a record of 59 years during the 1st to 3rd centuries CE, divided into three sequences separated by plaster layers. Annual carbonate layers show an alternation of sparite, formed in winter, and micrite, formed in summer. Brown bands at the base of many sparite layers probably correspond to large rainstorms in early winter. A fine lamination present in the brown bands may be diurnal in origin. Stable isotope and trace element dat…