Paleo Mega Lake of Rey Identification and Reconstruction of Quaternary Lake in Central Iran

Abstract

This study presents evidence for the existence of a vast and ancient lake that occupyed a large area of central Iran during the Holocene. The northwestern fringe of the lake, located in the southeast of Tehran, was chosen as the study area. Remains of a Paleo Lake scarp was studied using aerial photographs, Quick Bird satellite imagery, and topographic maps. Furthermore, archeological sites within the region were identified and located, and evidence for the lake was obtained through correlation of these data. Eight shorelines were identified between 1100 -950 m above sea level, with a depth of 3 -15 m, and a 43 km in lenght. The results indicated that the active Quaternary faults named North Rey, Kahrizak, and South Rey are in fact the three main topographic levels of the paleo lake and from now on they cannot be considered as the faults. Soil granulation and thin sections showed the presence of non-compacted lake sediments. Results revealed a remarkable association between the location of ancient settlements and altitude of the identified paleo shorelines. All settlements older than 5,000 years were located at 1,000 m. Certainly, the past climate of this region was very different from its contemporary one. Dating studies will provide valuable information about the exact age of the Paleo -Lake and paleo climate changes.

Landslide susceptibility zoning based on Rock Engineering System application to the Tehran case study

“…The change in tectonic regime and the direction of stress prevailing in Iran, coupled with climate variations, especially the end of the last glacial period in the Younger Dryas, has led to extensive instability in the slopes of Iran. On the other hand, the desiccation of the Paleo Mega Lake of Rey (Habibi et al, 2023;Jarahi, 2019Jarahi, , 2021Jarahi et al, 2022aJarahi et al, , 2022bNajafian et al, 2022) Today, most studies conducted on landslide susceptibility mapping utilize digital tools for managing spatial data, such as Geographic Information Systems (GIS). Specifically, GIS-based techniques are highly suitable for landslide susceptibility mapping, as they incorporate predisposing factors (e.g., geology, topography) into the GIS environment and combine them with the spatial distribution of landslides (Bonham-Carter & Bonham-Carter, 1994;Chung, 1983;Papathanassiou et al, 2013;Van Westen et al, 2003).…”

“…The change in tectonic regime and the direction of stress prevailing in Iran, coupled with climate variations, especially the end of the last glacial period in the Younger Dryas, has led to extensive instability in the slopes of Iran. On the other hand, the desiccation of the Paleo Mega Lake of Rey (Habibi et al., 2023; Jarahi, 2019, 2021; Jarahi et al., 2022a, 2022b; Najafian et al., 2022) as the main water resources and climatic cycle of Central Iran and the southern Alborz mountain range has resulted in changes in river base levels and channel incision. The deepening of river beds and the formation of alluvial terraces are among the factors contributing to the formation of unstable slopes, especially in the Tehran region.…”