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Umm al Binni lake is a mostly dry lake in Maysan Governorate in southern Iraq within the Central Marshes. The 3.4 km wide lake is approximately 45 km northwest of the Tigris–Euphrates confluence. Because of its shape and location, it has been suggested to represent an impact crater. The name means "Mother of Mesopotamic barbels", after the ''binni'' (Mesopotamic Barbel, ''Mesopotamichthys sharpeyi''), a fish species formerly common in the lake and traditionally harvested by the spear-and-poison fishermen of the Marsh Arabs. Even though the lake has fallen dry in modern times, its name attests to the former abundance of ''M. sharpeyi'', of which it may have been a spawning ground. == Evidence as an impact crater == Using satellite imagery, Master (2001, 2002) suggests the 3.4 km diameter dry lake may be an impact crater based on its nearly circular, slightly polygonal shape, rim shape, and contrasting shape to other lakes in the region. As to its origin, Master rules out Karst solution, salt doming, tectonic deformation, and igneous intrusion as well as possible bombing or man-made origins of the structure. Master (2001, 2002) estimates the age of the crater to be less than 5,000 years, due to the deposition of sediments of the Tigris-Euphrates plain as a result of the 130–150 km seaward progradation of the Persian Gulf during that time period (Larsen & Evans 1978). A lack of writings describing this event by contemporary authors, such as Herodotus (484–425 BC) and Nearchus (360–300 BC) or later historians, suggests the impact may have taken place between 3000 and 5000 years BP (Master 2002). During this time period, the Al Amarah region was under the Persian Gulf at a depth of approximately 10 m (Larsen & Evans 1978: 237). Impact-induced tsunamis would have devastated coastal Sumerian cities. This may provide an alternate origin of the 2.6 m sediment layer discovered during an excavation of the Sumerian city of Ur by Leonard Woolley in 1922-1934. Descriptive passages in The Epic of Gilgamesh (circa 1600–1800 BCE) may describe such an impact and tsunami, suggesting a link to the Sumerian Deluge (Matthews 2001; Britt 2001): ''...and the seven judges of Hell, the Annunaki, raised their torches, lighting the land with their livid flame. A stupor of despair went up to heaven when the god of the storm turned daylight into darkness, when he smashed the land like a cup. One whole day the tempest raged, gathering fury as it went, it poured over the people like tides of battle; a man could not see his brother nor the people be seen from heaven. Even the gods were terrified at the flood, they fled to the highest heaven, the firmament of Anu; they crouched against the walls, cowering like curs.'' (Sanders 1960). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Umm al Binni lake」の詳細全文を読む スポンサード リンク
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