Abstract The draining of the herein introduced ancient Lake Elji, and the subsequent erosion of its lacustrine sediments, were necessary precursors to the Late Epipalaeolithic (Natufian) and later settlement of Petra. This study investigates this geological history and relates it to human occupation of the broader region. Widespread carbonates consisting of algal mat deposits, beach rocks, and rhizoliths are consistently present at the 1060 m contour line of what is believed to be the shoreline of Lake Elji in the Petra basin. Well sorted siliciclastic fluvio-lacustrine sediments at lower elevations and human settlement patterns all indicate that a standing body of water once existed in the area. Stable isotopes of carbon and oxygen, as well as the fossil assemblages and the textures of the carbonate deposits, suggest that the body of water was an open lake with regular outflows. A sill has been identified at Ras Btahi, indicating a southward outflow direction, as opposed to the current drainage pattern towards the west. The lack of a basin closure towards the west at the time, as evidenced by thick, low energy sediment accumulations, suggest that tectonic movements were responsible for breaching the lake and establishing the current hydrological pattern. Results obtained from the optical stimulated luminiscence (OSL) in the palaeolake sediments indicate that the basin was closed from at least 100 Ka up to approximately 9 Ky. This timeline is also supported by the distribution of archaeological sites in the area and a previously documented massive erosional event at the end of this period. Subsequent gradual denudation of the basin sediments allowed for the settlement in the center of Petra during the Early Nabatean period.

中文翻译：

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埃尔吉湖和约旦佩特拉演化的地质观点

摘要 这里引入的古埃尔吉湖的排水以及随后湖相沉积物的侵蚀，是晚上旧石器时代（纳图夫阶）和后来佩特拉定居的必要先兆。这项研究调查了这一地质历史，并将其与人类对更广泛地区的占领联系起来。由藻垫沉积物、海滩岩石和根石组成的广泛碳酸盐一直存在于被认为是佩特拉盆地 Elji 湖海岸线的 1060 m 等高线上。低海拔的分选良好的硅质碎屑河湖沉积物和人类聚居模式都表明该地区曾经存在过一个静水体。碳和氧的稳定同位素，以及化石组合和碳酸盐沉积物的质地，表明水体是一个开放的湖泊，有规律的流出。在 Ras Btahi 发现了一个门槛，表明向南流出方向，而不是目前向西的排水模式。厚厚的低能量沉积物堆积证明当时没有向西关闭盆地，这表明构造运动是造成湖泊破裂和建立当前水文格局的原因。从古湖沉积物中的光学受激发光 (OSL) 获得的结果表明，该盆地从至少 100 Ka 到大约 9 Ky 关闭。该时间线也得到该地区考古遗址分布和先前记录的大量这一时期结束时的侵蚀事件。