Indus valley civilization spread >1 million square kilometers across Indus River from the Arabian Sea to the Ganges, over what is now Pakistan, northwest India and eastern Afghanistan, the Indus civilization was the largest—but least known—of the first great urban cultures that also included Egypt and Mesopotamia. Harappans, named for one of their largest cities,lived close to river for fertile soil.
Woods Hole Oceanographic Institution (WHOI) and lead author of the study published May 2012, in the Proceedings of the National Academy of Sciences, establishes SARASWATI RIVER EXISTED ABOUT 4900 YRS AGO BEFORE IT WAS DRIED UP per satellite images.
"Until now, speculations abounded about the links between this mysterious ancient culture and its life-giving mighty rivers."
This complex culture in South Asia with a population that at its peak may have reached 10 percent of the world's inhabitants, was completely forgotten until 1920's.
The new study suggests that the decline in monsoon rains led to weakened river dynamics, and played a critical role both in the development and the collapse of the Harappan culture, which relied on river floods to fuel their agricultural surpluses.
The archaeological sites along the dried up Sarasvati River basin are represented by black dots.
From the new research, a vast picture of 10,000 years of changing landscapes emerges. Before the plain was massively settled, the wild and forceful Indus and its tributaries flowing from the Himalaya cut valleys into their own deposits and left high "interfluvial" stretches of land between them.
Among the most striking features the researchers identified is a mounded plain, 20 meters high, > 100 kilometers wide, and running almost 1000 kilometers along the Indus, called"Indus mega-ridge," built by the river as it purged itself of sediment along its course.
The mega-ridge is a surprising indicator of the stability of Indus plain landscape over the last four millennia.
Journal reference:Proceedings of the National Academy of Sciences
Provided byWoods Hole Oceanographic Institution