Watermass structure at benthic disturbance site (INDEX area) and anticipated mining effects on hydro-physical properties

• Main Authors: RameshBabu, V., Murty, V.S.N., Suryanarayana, A., Beena, B.S., Niranjan, K
• Format: Conference Object
• Language: English
• Published: International Society of Offshore and Polar Engineers, Cupertino, CA (USA) 1999
• Subjects: deep-water masses; temperature; salinity; environmental impact; mining; mine tailings; benthic environment; Antarctic; Indian; Antarc*
• Online Access: http://drs.nio.org/drs/handle/2264/1829

Watermass properties were obtained in the Indian Deep Sea Experiment (INDEX) area during pre- (27 May-8 July 1997) and post- (22 July-5 September, 1997) benthic disturbance periods respectively. Watermass (Temperature-Salinity: T-S) structure was characterised with the presence of North Indian Deep Waters having a salinity maximum of 34.75 psu around 45.7 sigma isopycnal. A near-depth uniformity in temperature and salinity in the abyssal water column was due to Antarctic Bottom Watermass with 45.95 sigma. The light transmission profiles showed very negligible changes (1 to 2%) from pre- to post-disturbance periods suggesting that the bottom waters were not affected by the sediment plumes. The intrusion depths of surface-discharged mining effluents were assessed and the anticipated mining effects in surface layers are discussed.