Lake Qarun
Coordinates: 29°27′13″N 30°34′51″E / 29.45361°N 30.58083°E
Lake Moeris (Ancient Greek: Μοῖρις, genitive Μοίριδος) is an ancient lake in the northwest of the Faiyum Oasis, 80 km (50 mi) southwest of Cairo, Egypt. In prehistory, it was a freshwater lake, with an area estimated to vary between 1,270 km² (490 mi²) and 1,700 km² (656 mi²).
It persists today as a smaller saltwater lake called Birket Qarun. The lake's surface is 43 m (140 ft) below sea-level, and covers about 202 square kilometres (78 sq mi).
It is a source for tilapia and other fish from the local area.
The prehistoric mammal Moeritherium was found in this area.
When the Mediterranean Sea was a hot dry hollow near the end of the Messinian Salinity Crisis in the late Miocene, Faiyum was a dry hollow, and the Nile flowed past it at the bottom of a canyon (2,400 m deep or more where Cairo is now). After the Mediterranean reflooded at the end of the Miocene, the Nile canyon became an arm of the sea reaching inland further than Aswan. Over geological time that sea arm gradually filled with silt and became the Nile valley.
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