A seminar on climate change and disaster management was held at Bangladesh Open University (BOU) on its campus in Gazipur on Monday.
In the seminar, Dr Jennifer Pickering of Memphis University, US presented the keynote paper on "Rethinking Geomorphic Drivers in Bengal: Impacts of Megafloods on Fluvial-Deltaic System Dynamics", said a press release.
BOU Vice Chancellor Professor Dr Syed Humayun Akhter and Professor Dr Mike Blum of University of Kansas, US, BOU Pro-VC (Administration) Professor Dr Nasim Banu, Pro-VC (Academic) Professor Dr Mahbuba Nasreen, Treasurer Professor Mostafa Azad Kamal and Open School Dean Professor Sabina Yeasmin addressed the seminar, among others.
While addressing on Megafloods on Fluvial-Deltaic System, Dr Jennifer said that the paleo valley floor is defined by a gravel unit containing boulder-sized casts up to 30cm in diameter, deposited after ca. 30 ka but before ca. 9 ka.
The current research indicates that glacial-lake outburst floods sourced from the Tibetan reaches of the Brahmaputra were routed through the low stand valley, producing mega flood-scale discharge capable of transporting gravel and cannibalizing the valley margins, she added.
Dr Jennifer said the timing of these glacial-lake outburst flood-driven discharge events was coincident with valley development and explains the anomalously large width of the valley and basal gravel surface.
Despite the underfit scale of Brahmaputra discharge following the last glacial period, a strengthening monsoon and high sediment discharge in the early Holocene subsequently contributed to the efficient infilling of the massive paleo valley by the mid-Holocene, she added.
