violence on Mars also carved the huge channel of the northern Kasei
Valles. Although it is some 500 kilometers wide and nearly 3,000
kilometers long, some scientists think the catastrophic flood that
carved the valley may have lasted only months.
The water flow
rate through Kasei could have been a billion cubic meters per second,
dwarfing the capacity of channels on Earth like the Strait of Gibraltar
( 60 million cubic metres per second ) and the Amazon River ( 300,000
cubic metres per second ).