Expanded and integrated seismostratigraphic analysis of the Weddell Sea region, Antarctica

• Main Authors: Huang, Xiaoxia, Gohl, Karsten
• Format: Conference Object
• Language: unknown
• Published: 2013
• Subjects: Antarc*; Antarctic; Antarctica; Ice Shelves; Southern Ocean; Weddell Sea
• Online Access: https://epic.awi.de/id/eprint/32559/; https://hdl.handle.net/10013/epic.41148

The Weddell Sea region of the Southern Ocean has a particular significance to ocean circulation, transport of ice masses and global climate variations due to its giant Weddell Sea gyre. This clockwise circulating ocean gyre system is responsible for the exchange and mixing of Antarctic Deep Water with the global circulation as well as the transport of ice masses from the Filchner-Ronne Ice-Shelves of the Antarctic mainland to the Atlantic Ocean. Understanding the development of the Weddell Sea gyre system is linked to the reconstruction of the development of sedimentation and the resulting paleobathymetry. The main objective of this project is to analyze the seismostratigraphic records and to create a digital paleobathymetric map series of the greater Weddell Sea region from pre-glacial times (about 50 Ma) to the present. The data include all existing seismic data and drilling information from the area. Here, we present the construction of a unified stratigraphic model and sediment thickness grids as a first step in developing a paleobathymetric grid series. Three transects with a total of up to 4000 km long multichannel seismic reflection profiles from various organizations were initially used to interpret horizons in order to define the basin-wide seismostratigraphy(fig.1, fig.2). We integrated local stratigraphic models of Miller et al. (1990), Rogenhagen et al. (2004), Maldonado et al. (2006) and Rebesco et al. (2008) and expanded the 2D transect model from across the Weddell Sea of Lindeque et al. (2013) by adding more than 200 seismic lines and identified the pre-glacial to glacial sedimentary units. Borehole data of ODP Leg 113 and SHALDRIL constrain sediment ages locally. Three basic sedimentary units are identified as being deposited under pre-glacial (~148-34Ma), transitional (~34-12Ma) and full-glacial (~12-1Ma) conditions. We generated sediment depth and thickness grids of these three units. The sediment thickness grids allow us to compare the pre-glacially dominated and glacially dominated ...