Activity 6B

Activity 6B – Hydrogeology – Himalayan fluvial system and ground waters

Chemical and physical weathering of rocks on the continents drive the geochemical cycles of elements on the earth’s surface. The intensity and the nature of weathering and erosion of rocks are imprinted in the composition of dissolved and particulate phases of rivers. Chemical weathering of rocks, specifically silicate rocks exerts significant control on the CO₂ budget of the atmosphere on long time scales. The role of change in silicate weathering as a driver of climate change is a topic of debate among geochemists. In this context, the uplift of the Himalaya in contributing to enhanced silicate weathering has been a subject of investigation during the last couple of decades. Among the various rivers draining the Himalaya, chemical weathering in the Indus – Ganga – Brahmaputra (I-G-B) systems serve as a major pathway for transporting the weathering products from the Himalaya to the Bay of Bengal. This system ranks first among the World Rivers in sediment supply to the ocean and fourth in water discharge. Our activity contains the issues related to water, and is summarized as follows.

Himalayan Fluvial Systems (I-G-B): Fluvial landforms, extreme events, erosion-climate-tectonic coupling, migration of channels, material & water fluxes to the Oceans, Hydrograph separation studies, and natural pathways for CO₂sequestration on Geological time scales
Rejuvenation of Himalayan streams and springs
Ground water dynamics and Karst Aquifers in the I-G-B Himalaya and plains.
Anthropogenic forcing of Himalayan Rivers from their source to Sink