End of Indus

At http://phys.org/print257415019.html … a new study, archaeological and geological, says it has the evidence that climate change was a big ingredient in the collapse of the Indus civilisation 4000 years ago. The Indus culture was common right across Pakistan, eastern Afghanistan and NW India for some one thousand years, the third millennium BC – and thrived at the same time as Old Kingdom Egypt and Dynastic Sumeria, and like them had a riverine and irrigation agriculture. Many remains now lie stranded in the desert, on a now dry river bed. The study suggests a decline in monsoon rains was responsible – before 5200 years ago, and afterwards. Crop yields fell. It is established that in the early Holocene, until 3200BC, monsoon rains were enough to allow normal agriculture production. After 3200BC the precipitation rate fell dramatically, as it did in Arabia and Egypt, and irrigation technology was developed, channeling the river water into the fields (exactly like the Sumerians, their contemporaries). However, the SDaraswati river was not fed by water cascading down the Himalayas but by the monsoon rains – and gradually it dried up. That is the conjecture. After 2000BC people migrated into the Ganges basin where the monsoon rains were reliable. It  doesn't appear, from the press release and abstract, that earthquakes and tectonic activity figure in the cause of decline – and shift of river channel.