Age determination of Petra's engineered landscape – optically stimulated luminescence (OSL) and radiocarbon ages of runoff terrace systems in the Eastern Highlands of Jordan

Abstract The unfavourable mountainous environment of the Petra region in southern Jordan was modified by ancient engineers to supply the Nabataean/Roman city of Petra with food and water. The area was reclaimed by installing extended runoff terrace systems and hydraulic structures. The agricultural terrace systems have so far been dated based on surface pottery, and the chronology of the systems is under debate. In this study, optically stimulated luminescence (OSL) and radiocarbon dating techniques were successfully applied to date these terrace systems. Samples were taken from the fills of agricultural terraces and underneath their walls to determine the chronology of the construction, use and abandonment of the agricultural terraces. The results suggest that runoff farming in the Petra region started around the beginning of the Common Era, and construction, use and maintenance lasted at least until 800 AD.