Erosional marks on consolidated banks and slump blocks in the Rupen River, north-west India



Erosional marks, including grooves, current crescents and flutes, are present on banks and slump blocks of the Rupen River on the semi-arid plains of north-west India. The channel has a width:depth ratio of 6, and is incised up to 8 m through well consolidated, fine-grained aeolian sediment dated at ∼ 20–60 ka. Pedogenic carbonate nodules embedded in the channel walls have localized scour, and reworked carbonate particles probably promoted corrasion during strong seasonal flow. Similar erosional marks are apparently scarce on modern river banks, and a distinctive combination of conditions, including a consolidated substrate and strong flow in a confined channel, is probably required for their generation and preservation on channel walls and on slump blocks.