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.