Saraswati River in northern India (Haryana) and its role in populating the Harappan civilization sites—A study based on remote sensing, sedimentology, and strata chronology

The Saraswati River used to flow from the glaciated peaks of the Himalaya to the Arabian sea, covering a distance of about 1800 km. It possibly sustained the Harappan civilization in the Indian subcontinent. This river has been studied as a part of the Ghaggar-Satluj-Hakra-Nara channel system in India and Pakistan. This study investigated its independent existence and evolution in the Himalayan foothill terrain and the proximal alluvial plains. Use of satellite imagery, shuttle radar topography mission data, accelerator mass spectrometry14C dating and optically stimulated luminescence chronology is being made to identify the possible palaeo-path of this ancient river and to characterize the trench sediment log architecture of the Saraswati River palaeochannels in northern India (Haryana). Our investigations reveal that this river formed a dense web of interconnecting channels which are continuously networked for more than 2,984 km in Haryana and their individual floodplain width varies from 1.5 to 13 km. The Harappan settlements in Haryana and Rajasthan nucleated and prospered in the fertile channel bars and interfluves of this river system. Majority of these habitation sites were located within a radius of less than 500 m from these palaeo-water channel networks. Enormous amount of water was flowing through this channel network until BC 11,147. Sediment characteristics and their chronology reveal that flow of water in the river channel decreased with time as the glacial cover diminished. The varying thickness of clay beds in sediment logs is indicative of the fluctuations in water flow possibly as a consequence of terrain slope modifications and consequent gradual channel avulsion, climate change, and global drought events. The flow of water continued through the Himalayan foothill input channels of the palaeo-Saraswati River in Haryana until AD 1402.