A high-resolution palaeoenvironmental record from carbonate deposits in the Roman aqueduct of Patara, SW Turkey, from the time of Nero

Abstract

An inscription on the supporting wall of the inverted siphon of the aqueduct of the ancient Roman city of Patara, SW Turkey, explains how the wall collapsed during an earthquake and was subsequently restored. Carbonate deposits formed inside the aqueduct channel show cyclic stable isotope changes representing 17 years of deposition. This sequence, together with the text of the inscription, allows dating the earthquake to 68 AD and the original inauguration of the aqueduct to the winter of 51/52 AD. Thus, the carbonate deposits represent a high-resolution record of palaeotemperature and precipitation for SW Turkey covering the complete reign of the Emperor Nero. The period shows a cooling and drying trend after an initial warm and more humid period, interrupted by a few anomalous years. These 2 cm of calcite highlight the significance of carbonate deposits in ancient water supply systems as a high-resolution archive for palaeoclimate, palaeoseismology and archaeology.

Geochemical study of carbonate concretions from the aqueduct of Nîmes (southern France): a climatic record for the first centuries AD?

“…Aqueduct channels are shallowly buried structures that can experience seasonal temperature changes, though minor 4 . The study of other sinter deposits from southwest Turkey and southern France evidenced that the bright laminae, which correspond to the winter rains, were associated with high δ 18 O values 4 , 11 , 24 . The same authors propose that the seasonal changes in the isotopic composition of rainfall cannot explain this periodicity in the isotopic signal because most rainfall in these regions occurs in winter, and the mixing in the karst is likely to remove this seasonal pattern from the spring water 4 , 25 .…”

Roman Builders Facing the Risk of Disaster: Coupling Archaeological and Geochemical Analyses on a Section of the ‘Aqua Augusta’ (the Roman Serino Aqueduct, Southern Italy)

“…,b; Passchier et al . ). However, not all the samples show cycles (see, e.g., sample P19 in Sürmelihindi et al .…”

“…,b; Passchier et al . ,b). They are commonly characterized by alternating clear and darker laminae that can be directly linked to annual cycles and therefore can provide an annual record of operation and high‐resolution palaeoenvironmental proxies (e.g., Sürmelihindi et al .…”

The second century CE Roman watermills of Barbegal: Unraveling the enigma of one of the oldest industrial complexes

“…This method has previously been applied to carbonate deposits from ancient and modern aqueducts, demonstrating that sinusoidal, mirror-like oscillations of δ 18 O and δ 13 C reflect seasonal variations in the conditions of carbonate precipitation ( Fig. 4 , C and D) ( 14 – 16 ). Variation in δ 18 O is attributed to isotope fractionation in response to seasonal changes in water temperature in the channel, whereby high δ 18 O values represent cold water during winter and low values represent warm summer water ( Fig.…”

“…We believe that light was the key factor causing the change in fabric, with initial deposition in dark conditions, hampering growth of photosynthetic organisms, followed by a sudden change near the end of the depositional history toward biogenically dominated calcite precipitation. The fabric of the main deposits is identical to calcite formed in closed aqueduct channels with fast flowing water ( 13 – 16 , 18 ). This suggest that the Barbegal mills either were shaded by overhanging roofs or, more likely, were enclosed within buildings during the formation of dense sparite ( Fig.…”