Recent changes in Jadukata fan (Bangladesh) in response to Holocene tectonics

Abstract

Originating from the base of southern foothill of the Shillong Plateau, Jadukata fan is one of the largest fans situated in the mid-northern edge of Bangladesh. The area in and around Jadukata fan lies in the active and complex Himalayan tectonic zone as envisaged by the high seismicity in the area. The fan was studied with the main objective of understanding the formation and development of this tropical, humid alluvial fan in relation to Holocene tectonics. The geological and geomorphological inferences are based on multi-temporal remote sensing data. Information extracted from RS data were checked in the field and compared with other relevant data and information. Identified evidences are topographic expression, anomalous and preferred channel migration, aligned bends in consecutive channels, change in sediments distribution pattern etc. on the fan. These geological and geomorphological evidences as well as past and recent seismic events of the area strongly indicate that the alluvial fan building processes is being controlled by the neotectonic activities. The article also highlights the reasons for the occurrences of the natural hazard based on on-going tectonic activities.